diff --git a/Cargo.lock b/Cargo.lock
index 15e3469c42..7b459d154a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -207,7 +207,7 @@ dependencies = [
  "futures-io",
  "futures-timer",
  "kv-log-macro",
- "log 0.4.11",
+ "log 0.4.14",
  "memchr 2.3.3",
  "num_cpus",
  "once_cell",
@@ -283,7 +283,7 @@ dependencies = [
  "libp2p-plaintext",
  "libp2p-swarm",
  "libp2p-yamux",
- "log 0.4.11",
+ "log 0.4.14",
  "lru 0.4.3",
  "prost",
  "prost-build",
@@ -437,6 +437,20 @@ dependencies = [
  "secp256k1",
 ]
 
+[[package]]
+name = "bitcoin-spv"
+version = "5.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "aefc3d887fcbb15bd92c1490308bf62df200ff338a9b67e4863dc7012c052cce"
+dependencies = [
+ "hex 0.4.3",
+ "primitive-types 0.7.3",
+ "ripemd160 0.8.0",
+ "serde",
+ "serde_json",
+ "sha2 0.8.2",
+]
+
 [[package]]
 name = "bitcoin_hashes"
 version = "0.10.0"
@@ -481,6 +495,16 @@ dependencies = [
  "typenum",
 ]
 
+[[package]]
+name = "bitvec"
+version = "0.17.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "41262f11d771fd4a61aa3ce019fca363b4b6c282fca9da2a31186d3965a47a5c"
+dependencies = [
+ "either",
+ "radium 0.3.0",
+]
+
 [[package]]
 name = "bitvec"
 version = "0.18.5"
@@ -643,6 +667,12 @@ version = "3.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2e8c087f005730276d1096a652e92a8bacee2e2472bcc9715a74d2bec38b5820"
 
+[[package]]
+name = "byte-slice-cast"
+version = "0.3.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b0a5e3906bcbf133e33c1d4d95afc664ad37fbdb9f6568d8043e7ea8c27d93d3"
+
 [[package]]
 name = "byte-slice-cast"
 version = "1.0.0"
@@ -790,15 +820,6 @@ dependencies = [
  "bitflags",
 ]
 
-[[package]]
-name = "cloudabi"
-version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4344512281c643ae7638bbabc3af17a11307803ec8f0fcad9fae512a8bf36467"
-dependencies = [
- "bitflags",
-]
-
 [[package]]
 name = "coins"
 version = "0.1.0"
@@ -844,7 +865,7 @@ dependencies = [
  "metrics",
  "mocktopus",
  "num-traits 0.2.12",
- "parking_lot 0.11.1",
+ "parking_lot 0.12.0",
  "primitives",
  "prost",
  "prost-build",
@@ -867,6 +888,7 @@ dependencies = [
  "serialization_derive",
  "sha2 0.8.2",
  "sha3",
+ "spv_validation",
  "tokio",
  "tokio-rustls",
  "utxo_signer",
@@ -944,7 +966,7 @@ dependencies = [
  "lazy_static",
  "libc",
  "lightning",
- "log 0.4.11",
+ "log 0.4.14",
  "log4rs",
  "metrics",
  "metrics-core",
@@ -953,7 +975,7 @@ dependencies = [
  "num-bigint 0.2.6",
  "num-rational",
  "num-traits 0.2.12",
- "parking_lot 0.11.1",
+ "parking_lot 0.12.0",
  "parking_lot_core 0.6.2",
  "paste",
  "primitives",
@@ -1051,11 +1073,11 @@ dependencies = [
 
 [[package]]
 name = "crc32fast"
-version = "1.2.0"
+version = "1.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ba125de2af0df55319f41944744ad91c71113bf74a4646efff39afe1f6842db1"
+checksum = "b540bd8bc810d3885c6ea91e2018302f68baba2129ab3e88f32389ee9370880d"
 dependencies = [
- "cfg-if 0.1.10",
+ "cfg-if 1.0.0",
 ]
 
 [[package]]
@@ -1140,7 +1162,7 @@ dependencies = [
  "crossterm_winapi",
  "libc",
  "mio",
- "parking_lot 0.11.1",
+ "parking_lot 0.11.2",
  "signal-hook",
  "signal-hook-mio",
  "winapi 0.3.9",
@@ -1183,7 +1205,7 @@ dependencies = [
  "hw_common",
  "keys",
  "num-traits 0.1.43",
- "parking_lot 0.11.1",
+ "parking_lot 0.12.0",
  "primitives",
  "rpc_task",
  "secp256k1",
@@ -1249,6 +1271,16 @@ dependencies = [
  "sct",
 ]
 
+[[package]]
+name = "ctor"
+version = "0.1.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7fbaabec2c953050352311293be5c6aba8e141ba19d6811862b232d6fd020484"
+dependencies = [
+ "quote 1.0.7",
+ "syn 1.0.72",
+]
+
 [[package]]
 name = "ctr"
 version = "0.7.0"
@@ -1302,7 +1334,7 @@ checksum = "72aa14c04dfae8dd7d8a2b1cb7ca2152618cd01336dbfe704b8dcbf8d41dbd69"
 name = "db_common"
 version = "0.1.0"
 dependencies = [
- "log 0.4.11",
+ "log 0.4.14",
  "rusqlite",
  "sql-builder",
  "uuid",
@@ -1467,7 +1499,7 @@ checksum = "44533bbbb3bb3c1fa17d9f2e4e38bbbaf8396ba82193c4cb1b6445d711445d36"
 dependencies = [
  "atty",
  "humantime 1.3.0",
- "log 0.4.11",
+ "log 0.4.14",
  "regex 1.4.6",
  "termcolor",
 ]
@@ -1568,7 +1600,7 @@ dependencies = [
  "fixed-hash 0.7.0",
  "impl-rlp",
  "impl-serde",
- "primitive-types",
+ "primitive-types 0.9.1",
  "uint 0.9.1",
 ]
 
@@ -1654,6 +1686,18 @@ dependencies = [
  "rustc-hex 2.1.0",
 ]
 
+[[package]]
+name = "fixed-hash"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "11498d382790b7a8f2fd211780bec78619bba81cdad3a283997c0c41f836759c"
+dependencies = [
+ "byteorder 1.4.3",
+ "rand 0.7.3",
+ "rustc-hex 2.1.0",
+ "static_assertions",
+]
+
 [[package]]
 name = "fixed-hash"
 version = "0.7.0"
@@ -2307,7 +2351,7 @@ dependencies = [
  "ct-logs",
  "futures-util",
  "hyper",
- "log 0.4.11",
+ "log 0.4.14",
  "rustls",
  "tokio",
  "tokio-rustls",
@@ -2372,13 +2416,22 @@ dependencies = [
  "version_check",
 ]
 
+[[package]]
+name = "impl-codec"
+version = "0.4.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1be51a921b067b0eaca2fad532d9400041561aa922221cc65f95a85641c6bf53"
+dependencies = [
+ "parity-scale-codec 1.3.7",
+]
+
 [[package]]
 name = "impl-codec"
 version = "0.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "161ebdfec3c8e3b52bf61c4f3550a1eea4f9579d10dc1b936f3171ebdcd6c443"
 dependencies = [
- "parity-scale-codec",
+ "parity-scale-codec 2.2.0",
 ]
 
 [[package]]
@@ -2422,9 +2475,15 @@ dependencies = [
 
 [[package]]
 name = "instant"
-version = "0.1.6"
+version = "0.1.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5b141fdc7836c525d4d594027d318c84161ca17aaf8113ab1f81ab93ae897485"
+checksum = "7a5bbe824c507c5da5956355e86a746d82e0e1464f65d862cc5e71da70e94b2c"
+dependencies = [
+ "cfg-if 1.0.0",
+ "js-sys",
+ "wasm-bindgen",
+ "web-sys",
+]
 
 [[package]]
 name = "iovec"
@@ -2570,7 +2629,7 @@ version = "1.0.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4ff57d6d215f7ca7eb35a9a64d656ba4d9d2bef114d741dc08048e75e2f5d418"
 dependencies = [
- "log 0.4.11",
+ "log 0.4.14",
 ]
 
 [[package]]
@@ -2594,9 +2653,9 @@ dependencies = [
 
 [[package]]
 name = "libc"
-version = "0.2.97"
+version = "0.2.118"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "12b8adadd720df158f4d70dfe7ccc6adb0472d7c55ca83445f6a5ab3e36f8fb6"
+checksum = "06e509672465a0504304aa87f9f176f2b2b716ed8fb105ebe5c02dc6dce96a94"
 
 [[package]]
 name = "libp2p"
@@ -2620,7 +2679,7 @@ dependencies = [
  "libp2p-wasm-ext",
  "libp2p-websocket",
  "multiaddr",
- "parking_lot 0.11.1",
+ "parking_lot 0.11.2",
  "pin-project 1.0.7",
  "smallvec 1.6.1",
  "wasm-timer",
@@ -2640,11 +2699,11 @@ dependencies = [
  "futures-timer",
  "lazy_static",
  "libsecp256k1",
- "log 0.4.11",
+ "log 0.4.14",
  "multiaddr",
  "multihash",
  "multistream-select",
- "parking_lot 0.11.1",
+ "parking_lot 0.11.2",
  "pin-project 1.0.7",
  "prost",
  "prost-build",
@@ -2666,7 +2725,7 @@ source = "git+https://github.com/libp2p/rust-libp2p.git#20183c1ea152f5bfe183543e
 dependencies = [
  "futures 0.3.15",
  "libp2p-core",
- "log 0.4.11",
+ "log 0.4.14",
  "smallvec 1.6.1",
  "trust-dns-resolver",
 ]
@@ -2695,7 +2754,7 @@ dependencies = [
  "futures 0.3.15",
  "libp2p-core",
  "libp2p-swarm",
- "log 0.4.11",
+ "log 0.4.14",
  "prost",
  "prost-build",
  "rand 0.7.3",
@@ -2711,9 +2770,9 @@ dependencies = [
  "bytes 1.1.0",
  "futures 0.3.15",
  "libp2p-core",
- "log 0.4.11",
+ "log 0.4.14",
  "nohash-hasher",
- "parking_lot 0.11.1",
+ "parking_lot 0.11.2",
  "rand 0.7.3",
  "smallvec 1.6.1",
  "unsigned-varint 0.7.0",
@@ -2729,7 +2788,7 @@ dependencies = [
  "futures 0.3.15",
  "lazy_static",
  "libp2p-core",
- "log 0.4.11",
+ "log 0.4.14",
  "prost",
  "prost-build",
  "rand 0.8.4",
@@ -2748,7 +2807,7 @@ dependencies = [
  "futures 0.3.15",
  "libp2p-core",
  "libp2p-swarm",
- "log 0.4.11",
+ "log 0.4.14",
  "rand 0.7.3",
  "void",
  "wasm-timer",
@@ -2763,7 +2822,7 @@ dependencies = [
  "bytes 1.1.0",
  "futures 0.3.15",
  "libp2p-core",
- "log 0.4.11",
+ "log 0.4.14",
  "prost",
  "prost-build",
  "unsigned-varint 0.7.0",
@@ -2780,7 +2839,7 @@ dependencies = [
  "futures 0.3.15",
  "libp2p-core",
  "libp2p-swarm",
- "log 0.4.11",
+ "log 0.4.14",
  "lru 0.6.0",
  "minicbor",
  "rand 0.7.3",
@@ -2797,7 +2856,7 @@ dependencies = [
  "either",
  "futures 0.3.15",
  "libp2p-core",
- "log 0.4.11",
+ "log 0.4.14",
  "rand 0.7.3",
  "smallvec 1.6.1",
  "void",
@@ -2824,7 +2883,7 @@ dependencies = [
  "ipnet",
  "libc",
  "libp2p-core",
- "log 0.4.11",
+ "log 0.4.14",
  "socket2 0.4.0",
  "tokio",
 ]
@@ -2851,7 +2910,7 @@ dependencies = [
  "futures 0.3.15",
  "futures-rustls",
  "libp2p-core",
- "log 0.4.11",
+ "log 0.4.14",
  "quicksink",
  "rw-stream-sink",
  "soketto",
@@ -2866,7 +2925,7 @@ source = "git+https://github.com/libp2p/rust-libp2p.git#20183c1ea152f5bfe183543e
 dependencies = [
  "futures 0.3.15",
  "libp2p-core",
- "parking_lot 0.11.1",
+ "parking_lot 0.11.2",
  "thiserror",
  "yamux",
 ]
@@ -3009,7 +3068,7 @@ dependencies = [
  "common",
  "libc",
  "lightning",
- "parking_lot 0.11.1",
+ "parking_lot 0.12.0",
  "secp256k1",
  "serde_json",
  "winapi 0.3.9",
@@ -3042,9 +3101,9 @@ dependencies = [
 
 [[package]]
 name = "lock_api"
-version = "0.4.4"
+version = "0.4.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0382880606dff6d15c9476c416d18690b72742aa7b605bb6dd6ec9030fbf07eb"
+checksum = "88943dd7ef4a2e5a4bfa2753aaab3013e34ce2533d1996fb18ef591e315e2b3b"
 dependencies = [
  "scopeguard 1.1.0",
 ]
@@ -3055,17 +3114,18 @@ version = "0.3.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e19e8d5c34a3e0e2223db8e060f9e8264aeeb5c5fc64a4ee9965c062211c024b"
 dependencies = [
- "log 0.4.11",
+ "log 0.4.14",
 ]
 
 [[package]]
 name = "log"
-version = "0.4.11"
+version = "0.4.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4fabed175da42fed1fa0746b0ea71f412aa9d35e76e95e59b192c64b9dc2bf8b"
+checksum = "51b9bbe6c47d51fc3e1a9b945965946b4c44142ab8792c50835a980d362c2710"
 dependencies = [
- "cfg-if 0.1.10",
+ "cfg-if 1.0.0",
  "serde",
+ "value-bag",
 ]
 
 [[package]]
@@ -3087,9 +3147,9 @@ dependencies = [
  "fnv",
  "humantime 2.1.0",
  "libc",
- "log 0.4.11",
+ "log 0.4.14",
  "log-mdc",
- "parking_lot 0.11.1",
+ "parking_lot 0.11.2",
  "regex 1.4.6",
  "serde",
  "serde-value",
@@ -3285,7 +3345,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8c2bdb6314ec10835cd3293dd268473a835c02b7b352e788be788b3c6ca6bb16"
 dependencies = [
  "libc",
- "log 0.4.11",
+ "log 0.4.14",
  "miow",
  "ntapi",
  "winapi 0.3.9",
@@ -3339,6 +3399,7 @@ dependencies = [
  "http 0.2.1",
  "hw_common",
  "hyper",
+ "instant",
  "itertools 0.9.0",
  "js-sys",
  "keys",
@@ -3350,7 +3411,7 @@ dependencies = [
  "num-rational",
  "num-traits 0.2.12",
  "parity-util-mem",
- "parking_lot 0.11.1",
+ "parking_lot 0.12.0",
  "primitives",
  "rand 0.6.5",
  "rand 0.7.3",
@@ -3370,6 +3431,7 @@ dependencies = [
  "serialization_derive",
  "sp-runtime-interface",
  "sp-trie",
+ "spv_validation",
  "testcontainers",
  "tokio",
  "trie-db",
@@ -3399,7 +3461,7 @@ dependencies = [
  "lazy_static",
  "libp2p",
  "libp2p-floodsub 0.22.0",
- "log 0.4.11",
+ "log 0.4.14",
  "num-bigint 0.2.6",
  "num-rational",
  "rand 0.7.3",
@@ -3494,7 +3556,7 @@ source = "git+https://github.com/libp2p/rust-libp2p.git#20183c1ea152f5bfe183543e
 dependencies = [
  "bytes 1.1.0",
  "futures 0.3.15",
- "log 0.4.11",
+ "log 0.4.14",
  "pin-project 1.0.7",
  "smallvec 1.6.1",
  "unsigned-varint 0.7.0",
@@ -3660,6 +3722,18 @@ dependencies = [
  "group",
 ]
 
+[[package]]
+name = "parity-scale-codec"
+version = "1.3.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a4b26b16c7687c3075982af47719e481815df30bc544f7a6690763a25ca16e9d"
+dependencies = [
+ "arrayvec 0.5.1",
+ "bitvec 0.17.4",
+ "byte-slice-cast 0.3.5",
+ "serde",
+]
+
 [[package]]
 name = "parity-scale-codec"
 version = "2.2.0"
@@ -3668,7 +3742,7 @@ checksum = "8975095a2a03bbbdc70a74ab11a4f76a6d0b84680d87c68d722531b0ac28e8a9"
 dependencies = [
  "arrayvec 0.7.1",
  "bitvec 0.20.4",
- "byte-slice-cast",
+ "byte-slice-cast 1.0.0",
  "impl-trait-for-tuples",
  "parity-scale-codec-derive",
  "serde",
@@ -3704,8 +3778,8 @@ dependencies = [
  "impl-trait-for-tuples",
  "lru 0.6.0",
  "parity-util-mem-derive",
- "parking_lot 0.11.1",
- "primitive-types",
+ "parking_lot 0.11.2",
+ "primitive-types 0.9.1",
  "smallvec 1.6.1",
  "winapi 0.3.9",
 ]
@@ -3760,13 +3834,23 @@ dependencies = [
 
 [[package]]
 name = "parking_lot"
-version = "0.11.1"
+version = "0.11.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6d7744ac029df22dca6284efe4e898991d28e3085c706c972bcd7da4a27a15eb"
+checksum = "7d17b78036a60663b797adeaee46f5c9dfebb86948d1255007a1d6be0271ff99"
 dependencies = [
  "instant",
- "lock_api 0.4.4",
- "parking_lot_core 0.8.0",
+ "lock_api 0.4.6",
+ "parking_lot_core 0.8.5",
+]
+
+[[package]]
+name = "parking_lot"
+version = "0.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "87f5ec2493a61ac0506c0f4199f99070cbe83857b0337006a30f3e6719b8ef58"
+dependencies = [
+ "lock_api 0.4.6",
+ "parking_lot_core 0.9.1",
 ]
 
 [[package]]
@@ -3789,7 +3873,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b876b1b9e7ac6e1a74a6da34d25c42e17e8862aa409cbbbdcfc8d86c6f3bc62b"
 dependencies = [
  "cfg-if 0.1.10",
- "cloudabi 0.0.3",
+ "cloudabi",
  "libc",
  "redox_syscall 0.1.56",
  "rustc_version 0.2.3",
@@ -3804,7 +3888,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d58c7c768d4ba344e3e8d72518ac13e259d7c7ade24167003b8488e10b6740a3"
 dependencies = [
  "cfg-if 0.1.10",
- "cloudabi 0.0.3",
+ "cloudabi",
  "libc",
  "redox_syscall 0.1.56",
  "smallvec 1.6.1",
@@ -3813,19 +3897,31 @@ dependencies = [
 
 [[package]]
 name = "parking_lot_core"
-version = "0.8.0"
+version = "0.8.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c361aa727dd08437f2f1447be8b59a33b0edd15e0fcee698f935613d9efbca9b"
+checksum = "d76e8e1493bcac0d2766c42737f34458f1c8c50c0d23bcb24ea953affb273216"
 dependencies = [
- "cfg-if 0.1.10",
- "cloudabi 0.1.0",
+ "cfg-if 1.0.0",
  "instant",
  "libc",
- "redox_syscall 0.1.56",
+ "redox_syscall 0.2.8",
  "smallvec 1.6.1",
  "winapi 0.3.9",
 ]
 
+[[package]]
+name = "parking_lot_core"
+version = "0.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "28141e0cc4143da2443301914478dc976a61ffdb3f043058310c70df2fed8954"
+dependencies = [
+ "cfg-if 1.0.0",
+ "libc",
+ "redox_syscall 0.2.8",
+ "smallvec 1.6.1",
+ "windows-sys",
+]
+
 [[package]]
 name = "paste"
 version = "1.0.4"
@@ -3956,6 +4052,17 @@ version = "0.2.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "237a5ed80e274dbc66f86bd59c1e25edc039660be53194b5fe0a482e0f2612ea"
 
+[[package]]
+name = "primitive-types"
+version = "0.7.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7dd39dcacf71411ba488570da7bbc89b717225e46478b30ba99b92db6b149809"
+dependencies = [
+ "fixed-hash 0.6.1",
+ "impl-codec 0.4.2",
+ "uint 0.8.5",
+]
+
 [[package]]
 name = "primitive-types"
 version = "0.9.1"
@@ -3963,7 +4070,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "06345ee39fbccfb06ab45f3a1a5798d9dafa04cb8921a76d227040003a234b0e"
 dependencies = [
  "fixed-hash 0.7.0",
- "impl-codec",
+ "impl-codec 0.5.1",
  "impl-rlp",
  "impl-serde",
  "uint 0.9.1",
@@ -4061,7 +4168,7 @@ dependencies = [
  "bytes 1.1.0",
  "heck",
  "itertools 0.10.1",
- "log 0.4.11",
+ "log 0.4.14",
  "multimap",
  "petgraph",
  "prost",
@@ -4141,7 +4248,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a44883e74aa97ad63db83c4bf8ca490f02b2fc02f92575e720c8551e843c945f"
 dependencies = [
  "env_logger",
- "log 0.4.11",
+ "log 0.4.14",
  "rand 0.7.3",
  "rand_core 0.5.1",
 ]
@@ -4374,7 +4481,7 @@ version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7b75f676a1e053fc562eafbb47838d67c84801e38fc1ba459e8f180deabd5071"
 dependencies = [
- "cloudabi 0.0.3",
+ "cloudabi",
  "fuchsia-cprng",
  "libc",
  "rand_core 0.4.2",
@@ -4623,7 +4730,7 @@ version = "0.1.0"
 dependencies = [
  "chain",
  "keys",
- "log 0.4.11",
+ "log 0.4.14",
  "primitives",
  "rustc-hex 2.1.0",
  "script",
@@ -4733,7 +4840,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "35edb675feee39aec9c99fa5ff985081995a06d594114ae14cbe797ad7b7a6d7"
 dependencies = [
  "base64 0.13.0",
- "log 0.4.11",
+ "log 0.4.14",
  "ring",
  "sct",
  "webpki",
@@ -4782,7 +4889,7 @@ dependencies = [
  "blake2b_simd",
  "chain",
  "keys",
- "log 0.4.11",
+ "log 0.4.14",
  "primitives",
  "serde",
  "serialization",
@@ -5059,7 +5166,7 @@ dependencies = [
 name = "shared_ref_counter"
 version = "0.1.0"
 dependencies = [
- "log 0.4.11",
+ "log 0.4.14",
 ]
 
 [[package]]
@@ -5212,7 +5319,7 @@ dependencies = [
  "flate2",
  "futures 0.3.15",
  "httparse",
- "log 0.4.11",
+ "log 0.4.14",
  "rand 0.7.3",
  "sha-1",
 ]
@@ -5226,11 +5333,11 @@ dependencies = [
  "byteorder 1.4.3",
  "hash-db",
  "hash256-std-hasher",
- "log 0.4.11",
+ "log 0.4.14",
  "num-traits 0.2.12",
- "parity-scale-codec",
+ "parity-scale-codec 2.2.0",
  "parity-util-mem",
- "primitive-types",
+ "primitive-types 0.9.1",
  "secrecy",
  "sp-debug-derive",
  "sp-runtime-interface",
@@ -5257,8 +5364,8 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b2e5c88b4bc8d607e4e2ff767a85db58cf7101f3dd6064f06929342ea67fe8fb"
 dependencies = [
  "impl-trait-for-tuples",
- "parity-scale-codec",
- "primitive-types",
+ "parity-scale-codec 2.2.0",
+ "primitive-types 0.9.1",
  "sp-runtime-interface-proc-macro",
  "sp-std",
  "sp-storage",
@@ -5292,7 +5399,7 @@ version = "3.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "86af458d4a0251c490cdde9dcaaccb88d398f3b97ac6694cdd49ed9337e6b961"
 dependencies = [
- "parity-scale-codec",
+ "parity-scale-codec 2.2.0",
  "ref-cast",
  "sp-debug-derive",
  "sp-std",
@@ -5304,7 +5411,7 @@ version = "3.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "567382d8d4e14fb572752863b5cd57a78f9e9a6583332b590b726f061f3ea957"
 dependencies = [
- "parity-scale-codec",
+ "parity-scale-codec 2.2.0",
  "sp-std",
  "tracing",
  "tracing-core",
@@ -5318,7 +5425,7 @@ checksum = "b85b7f745da41ef825c6f7b93f1fdc897b03df94a4884adfbb70fbcd0aed1298"
 dependencies = [
  "hash-db",
  "memory-db",
- "parity-scale-codec",
+ "parity-scale-codec 2.2.0",
  "sp-core",
  "sp-std",
  "trie-db",
@@ -5332,7 +5439,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b214e125666a6416cf30a70cc6a5dacd34a4e5197f8a3d479f714af7e1dc7a47"
 dependencies = [
  "impl-trait-for-tuples",
- "parity-scale-codec",
+ "parity-scale-codec 2.2.0",
  "sp-std",
 ]
 
@@ -5342,6 +5449,17 @@ version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6e63cff320ae2c57904679ba7cb63280a3dc4613885beafb148ee7bf9aa9042d"
 
+[[package]]
+name = "spv_validation"
+version = "0.1.0"
+dependencies = [
+ "bitcoin-spv",
+ "chain",
+ "primitives",
+ "rustc-hex 2.1.0",
+ "serialization",
+]
+
 [[package]]
 name = "sql-builder"
 version = "3.1.1"
@@ -5488,7 +5606,7 @@ name = "tc_cli_client"
 version = "0.2.0"
 source = "git+https://github.com/artemii235/testcontainers-rs.git#65e738093488f1b37185af0f1d3cf0ffd23e840d"
 dependencies = [
- "log 0.4.11",
+ "log 0.4.14",
  "serde",
  "serde_derive",
  "serde_json",
@@ -5502,7 +5620,7 @@ source = "git+https://github.com/artemii235/testcontainers-rs.git#65e738093488f1
 dependencies = [
  "hex 0.3.2",
  "hmac 0.7.1",
- "log 0.4.11",
+ "log 0.4.14",
  "rand 0.7.3",
  "sha2 0.8.2",
  "tc_core",
@@ -5514,7 +5632,7 @@ version = "0.3.0"
 source = "git+https://github.com/artemii235/testcontainers-rs.git#65e738093488f1b37185af0f1d3cf0ffd23e840d"
 dependencies = [
  "debug_stub_derive",
- "log 0.4.11",
+ "log 0.4.14",
 ]
 
 [[package]]
@@ -5522,7 +5640,7 @@ name = "tc_dynamodb_local"
 version = "0.2.0"
 source = "git+https://github.com/artemii235/testcontainers-rs.git#65e738093488f1b37185af0f1d3cf0ffd23e840d"
 dependencies = [
- "log 0.4.11",
+ "log 0.4.14",
  "tc_core",
 ]
 
@@ -5547,7 +5665,7 @@ name = "tc_parity_parity"
 version = "0.5.0"
 source = "git+https://github.com/artemii235/testcontainers-rs.git#65e738093488f1b37185af0f1d3cf0ffd23e840d"
 dependencies = [
- "log 0.4.11",
+ "log 0.4.14",
  "tc_core",
 ]
 
@@ -5556,7 +5674,7 @@ name = "tc_postgres"
 version = "0.2.0"
 source = "git+https://github.com/artemii235/testcontainers-rs.git#65e738093488f1b37185af0f1d3cf0ffd23e840d"
 dependencies = [
- "log 0.4.11",
+ "log 0.4.14",
  "tc_core",
 ]
 
@@ -5821,7 +5939,7 @@ dependencies = [
  "bytes 1.1.0",
  "futures-core",
  "futures-sink",
- "log 0.4.11",
+ "log 0.4.14",
  "pin-project-lite 0.2.6",
  "tokio",
 ]
@@ -5900,7 +6018,7 @@ checksum = "9eac131e334e81b6b3be07399482042838adcd7957aa0010231d0813e39e02fa"
 dependencies = [
  "hash-db",
  "hashbrown 0.11.2",
- "log 0.4.11",
+ "log 0.4.14",
  "smallvec 1.6.1",
 ]
 
@@ -5929,7 +6047,7 @@ dependencies = [
  "idna 0.2.0",
  "ipnet",
  "lazy_static",
- "log 0.4.11",
+ "log 0.4.14",
  "rand 0.8.4",
  "smallvec 1.6.1",
  "thiserror",
@@ -5948,9 +6066,9 @@ dependencies = [
  "futures-util",
  "ipconfig",
  "lazy_static",
- "log 0.4.11",
+ "log 0.4.14",
  "lru-cache",
- "parking_lot 0.11.1",
+ "parking_lot 0.11.2",
  "resolv-conf",
  "smallvec 1.6.1",
  "thiserror",
@@ -5996,6 +6114,18 @@ dependencies = [
  "rustc-hex 2.1.0",
 ]
 
+[[package]]
+name = "uint"
+version = "0.8.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9db035e67dfaf7edd9aebfe8676afcd63eed53c8a4044fed514c8cccf1835177"
+dependencies = [
+ "byteorder 1.4.3",
+ "crunchy 0.2.2",
+ "rustc-hex 2.1.0",
+ "static_assertions",
+]
+
 [[package]]
 name = "uint"
 version = "0.9.1"
@@ -6151,6 +6281,16 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "value-bag"
+version = "1.0.0-alpha.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "79923f7731dc61ebfba3633098bf3ac533bbd35ccd8c57e7088d9a5eebe0263f"
+dependencies = [
+ "ctor",
+ "version_check",
+]
+
 [[package]]
 name = "vcpkg"
 version = "0.2.10"
@@ -6231,7 +6371,7 @@ version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1ce8a968cb1cd110d136ff8b819a556d6fb6d919363c61534f6860c7eb172ba0"
 dependencies = [
- "log 0.4.11",
+ "log 0.4.14",
  "try-lock",
 ]
 
@@ -6267,7 +6407,7 @@ checksum = "a317bf8f9fba2476b4b2c85ef4c4af8ff39c3c7f0cdfeed4f82c34a880aa837b"
 dependencies = [
  "bumpalo",
  "lazy_static",
- "log 0.4.11",
+ "log 0.4.14",
  "proc-macro2",
  "quote 1.0.7",
  "syn 1.0.72",
@@ -6377,7 +6517,7 @@ dependencies = [
  "ethereum-types 0.4.2",
  "futures 0.1.29",
  "jsonrpc-core",
- "log 0.4.11",
+ "log 0.4.14",
  "parking_lot 0.7.1",
  "rustc-hex 1.0.0",
  "serde",
@@ -6483,6 +6623,49 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
 
+[[package]]
+name = "windows-sys"
+version = "0.32.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3df6e476185f92a12c072be4a189a0210dcdcf512a1891d6dff9edb874deadc6"
+dependencies = [
+ "windows_aarch64_msvc",
+ "windows_i686_gnu",
+ "windows_i686_msvc",
+ "windows_x86_64_gnu",
+ "windows_x86_64_msvc",
+]
+
+[[package]]
+name = "windows_aarch64_msvc"
+version = "0.32.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d8e92753b1c443191654ec532f14c199742964a061be25d77d7a96f09db20bf5"
+
+[[package]]
+name = "windows_i686_gnu"
+version = "0.32.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6a711c68811799e017b6038e0922cb27a5e2f43a2ddb609fe0b6f3eeda9de615"
+
+[[package]]
+name = "windows_i686_msvc"
+version = "0.32.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "146c11bb1a02615db74680b32a68e2d61f553cc24c4eb5b4ca10311740e44172"
+
+[[package]]
+name = "windows_x86_64_gnu"
+version = "0.32.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c912b12f7454c6620635bbff3450962753834be2a594819bd5e945af18ec64bc"
+
+[[package]]
+name = "windows_x86_64_msvc"
+version = "0.32.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "504a2476202769977a040c6364301a3f65d0cc9e3fb08600b2bda150a0488316"
+
 [[package]]
 name = "winreg"
 version = "0.6.2"
@@ -6525,9 +6708,9 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e7d9028f208dd5e63c614be69f115c1b53cacc1111437d4c765185856666c107"
 dependencies = [
  "futures 0.3.15",
- "log 0.4.11",
+ "log 0.4.14",
  "nohash-hasher",
- "parking_lot 0.11.1",
+ "parking_lot 0.11.2",
  "rand 0.8.4",
  "static_assertions",
 ]
@@ -6590,7 +6773,7 @@ dependencies = [
  "hex 0.4.3",
  "jubjub",
  "lazy_static",
- "log 0.4.11",
+ "log 0.4.14",
  "rand 0.7.3",
  "rand_core 0.5.1",
  "ripemd160 0.9.1",
diff --git a/Cargo.toml b/Cargo.toml
index c2fd24f6c6..3ab42fb392 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -88,7 +88,7 @@ num-rational = { version = "0.2", features = ["serde", "bigint", "bigint-std"] }
 num-traits = "0.2"
 rpc = { path = "mm2src/mm2_bitcoin/rpc" }
 rpc_task = { path = "mm2src/rpc_task" }
-parking_lot = { version = "0.11", features = ["nightly"] }
+parking_lot = { version = "0.12.0", features = ["nightly"] }
 parity-util-mem = "0.9"
 # AP: portfolio RPCs are not documented and not used as of now
 # so the crate is disabled to speed up the entire removal of C code
@@ -110,6 +110,7 @@ ser_error = { path = "mm2src/derives/ser_error" }
 ser_error_derive = { path = "mm2src/derives/ser_error_derive" }
 serialization = { path = "mm2src/mm2_bitcoin/serialization" }
 serialization_derive = { path = "mm2src/mm2_bitcoin/serialization_derive" }
+spv_validation = { path = "mm2src/mm2_bitcoin/spv_validation" }
 sp-runtime-interface = { version = "3.0.0", default-features = false, features = ["disable_target_static_assertions"] }
 sp-trie = { version = "3.0", default-features = false }
 
@@ -124,6 +125,7 @@ wasm-bindgen = { version = "0.2.50", features = ["serde-serialize", "nightly"] }
 wasm-bindgen-futures = { version = "0.4.1" }
 wasm-bindgen-test = { version = "0.3.1" }
 web-sys = { version = "0.3.55", features = ["console"] }
+instant = {version = "0.1.12", features = ["wasm-bindgen"]}
 
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 dirs = { version = "1" }
diff --git a/README.md b/README.md
index 45f0c5c010..bbec952b81 100755
--- a/README.md
+++ b/README.md
@@ -15,8 +15,8 @@ The current state can be considered as very early alpha.
 1. (Optional) OSX: run `LIBRARY_PATH=/usr/local/opt/openssl/lib`
 1. Run
     ```
-    rustup install nightly-2021-12-16
-    rustup default nightly-2021-12-16
+    rustup install nightly-2022-02-01
+    rustup default nightly-2022-02-01
     rustup component add rustfmt-preview
     ```
 1. Run `cargo build` (or `cargo build -vv` to get verbose build output).
diff --git a/mm2src/coins/Cargo.toml b/mm2src/coins/Cargo.toml
index b7f1ea816d..57f1b2c7db 100644
--- a/mm2src/coins/Cargo.toml
+++ b/mm2src/coins/Cargo.toml
@@ -13,7 +13,7 @@ doctest = false
 
 [dependencies]
 async-std = { version = "1.5", features = ["unstable"] }
-async-trait = "0.1"
+async-trait = "0.1.52"
 base64 = "0.10.0"
 bigdecimal = { version = "0.1.0", features = ["serde"] }
 bip32 = { version = "0.2.2", default-features = false, features = ["alloc", "secp256k1-ffi"] }
@@ -52,7 +52,7 @@ lightning-invoice = "0.12.0"
 metrics = "0.12"
 mocktopus = "0.7.0"
 num-traits = "0.2"
-parking_lot = { version = "0.11", features = ["nightly"] }
+parking_lot = { version = "0.12.0", features = ["nightly"] }
 primitives = { path = "../mm2_bitcoin/primitives" }
 prost = "0.8"
 rand = { version = "0.7", features = ["std", "small_rng"] }
@@ -69,6 +69,7 @@ serde_derive = "1.0"
 serde_json = { version = "1.0", features = ["preserve_order", "raw_value"] }
 serialization = { path = "../mm2_bitcoin/serialization" }
 serialization_derive = { path = "../mm2_bitcoin/serialization_derive" }
+spv_validation = { path = "../mm2_bitcoin/spv_validation" }
 sha2 = "0.8"
 sha3 = "0.8"
 utxo_signer = { path = "utxo_signer" }
diff --git a/mm2src/coins/eth/eth_tests.rs b/mm2src/coins/eth/eth_tests.rs
index 120cdb93c3..111dfec0fb 100644
--- a/mm2src/coins/eth/eth_tests.rs
+++ b/mm2src/coins/eth/eth_tests.rs
@@ -1210,7 +1210,7 @@ fn polygon_check_if_my_payment_sent() {
     let request = json!({
         "method": "enable",
         "coin": "MATIC",
-        "urls": ["https://polygon-rpc.com"],
+        "urls": ["https://polygon-mainnet.g.alchemy.com/v2/9YYl6iMLmXXLoflMPHnMTC4Dcm2L2tFH"],
         "swap_contract_address": "0x9130b257d37a52e52f21054c4da3450c72f595ce",
     });
 
diff --git a/mm2src/coins/lightning_persister/Cargo.toml b/mm2src/coins/lightning_persister/Cargo.toml
index 34bf6eac52..4d246bc9bb 100644
--- a/mm2src/coins/lightning_persister/Cargo.toml
+++ b/mm2src/coins/lightning_persister/Cargo.toml
@@ -15,7 +15,7 @@ bitcoin = "0.27.1"
 common = { path = "../../common" }
 lightning = "0.0.104"
 libc = "0.2"
-parking_lot = { version = "0.11", features = ["nightly"] }
+parking_lot = { version = "0.12.0", features = ["nightly"] }
 secp256k1 = { version = "0.20" }
 serde_json = "1.0"
 
diff --git a/mm2src/coins/lp_coins.rs b/mm2src/coins/lp_coins.rs
index 4208ca4ee1..3be780f1a9 100644
--- a/mm2src/coins/lp_coins.rs
+++ b/mm2src/coins/lp_coins.rs
@@ -248,6 +248,7 @@ pub struct ValidatePaymentInput {
     pub secret_hash: Vec<u8>,
     pub amount: BigDecimal,
     pub swap_contract_address: Option<BytesJson>,
+    pub confirmations: u64,
 }
 
 /// Swap operations (mostly based on the Hash/Time locked transactions implemented by coin wallets).
diff --git a/mm2src/coins/qrc20/qrc20_tests.rs b/mm2src/coins/qrc20/qrc20_tests.rs
index c34e7e018b..41790cb4ab 100644
--- a/mm2src/coins/qrc20/qrc20_tests.rs
+++ b/mm2src/coins/qrc20/qrc20_tests.rs
@@ -131,6 +131,7 @@ fn test_validate_maker_payment() {
         secret_hash: vec![1; 20],
         amount: correct_amount.clone(),
         swap_contract_address: coin.swap_contract_address(),
+        confirmations: 1,
     };
 
     coin.validate_maker_payment(input.clone()).wait().unwrap();
@@ -851,6 +852,7 @@ fn test_validate_maker_payment_malicious() {
         secret_hash,
         amount,
         swap_contract_address: coin.swap_contract_address(),
+        confirmations: 1,
     };
     let error = coin
         .validate_maker_payment(input)
diff --git a/mm2src/coins/sql_tx_history_storage.rs b/mm2src/coins/sql_tx_history_storage.rs
index 71596b57a6..eef606f767 100644
--- a/mm2src/coins/sql_tx_history_storage.rs
+++ b/mm2src/coins/sql_tx_history_storage.rs
@@ -7,14 +7,12 @@ use common::{async_blocking, PagingOptionsEnum};
 use db_common::sqlite::rusqlite::types::Type;
 use db_common::sqlite::rusqlite::{Connection, Error as SqlError, Row, ToSql, NO_PARAMS};
 use db_common::sqlite::sql_builder::SqlBuilder;
-use db_common::sqlite::{offset_by_id, validate_table_name};
+use db_common::sqlite::{offset_by_id, string_from_row, validate_table_name, CHECK_TABLE_EXISTS_SQL};
 use rpc::v1::types::Bytes as BytesJson;
 use serde_json::{self as json};
 use std::convert::TryInto;
 use std::sync::{Arc, Mutex};
 
-const CHECK_TABLE_EXISTS_SQL: &str = "SELECT name FROM sqlite_master WHERE type='table' AND name=?1;";
-
 fn tx_history_table(ticker: &str) -> String { ticker.to_owned() + "_tx_history" }
 
 fn tx_cache_table(ticker: &str) -> String { ticker.to_owned() + "_tx_cache" }
@@ -194,17 +192,9 @@ where
     P::Item: ToSql,
     F: FnOnce(&Row<'_>) -> Result<T, SqlError>,
 {
-    let maybe_result = conn.query_row(query, params, map_fn);
-    if let Err(SqlError::QueryReturnedNoRows) = maybe_result {
-        return Ok(None);
-    }
-
-    let result = maybe_result?;
-    Ok(Some(result))
+    db_common::sqlite::query_single_row(conn, query, params, map_fn).map_err(MmError::new)
 }
 
-fn string_from_row(row: &Row<'_>) -> Result<String, SqlError> { row.get(0) }
-
 fn tx_details_from_row(row: &Row<'_>) -> Result<TransactionDetails, SqlError> {
     let json_string: String = row.get(0)?;
     json::from_str(&json_string).map_err(|e| SqlError::FromSqlConversionFailure(0, Type::Text, Box::new(e)))
diff --git a/mm2src/coins/utxo.rs b/mm2src/coins/utxo.rs
index 725211b6cb..8469fb1be4 100644
--- a/mm2src/coins/utxo.rs
+++ b/mm2src/coins/utxo.rs
@@ -29,13 +29,12 @@ mod bchd_pb;
 pub mod qtum;
 pub mod rpc_clients;
 pub mod slp;
+pub mod utxo_block_header_storage;
 pub mod utxo_builder;
 pub mod utxo_common;
 pub mod utxo_standard;
 pub mod utxo_withdraw;
 
-#[cfg(not(target_arch = "wasm32"))] pub mod tx_cache;
-
 use async_trait::async_trait;
 use bigdecimal::BigDecimal;
 use bitcoin::network::constants::Network as BitcoinNetwork;
@@ -69,6 +68,7 @@ use rpc::v1::types::{Bytes as BytesJson, Transaction as RpcTransaction, H256 as
 use script::{Builder, Script, SignatureVersion, TransactionInputSigner};
 use serde_json::{self as json, Value as Json};
 use serialization::{serialize, serialize_with_flags, SERIALIZE_TRANSACTION_WITNESS};
+use spv_validation::types::SPVError;
 use std::array::TryFromSliceError;
 use std::collections::{HashMap, HashSet};
 use std::convert::TryInto;
@@ -95,6 +95,13 @@ use super::{BalanceError, BalanceFut, BalanceResult, CoinsContext, DerivationMet
 use crate::coin_balance::{EnableCoinScanPolicy, HDAddressBalanceScanner};
 use crate::hd_wallet::{HDAccountOps, HDAccountsMutex, HDAddress, HDWalletCoinOps, HDWalletOps, InvalidBip44ChainError};
 use crate::hd_wallet_storage::{HDAccountStorageItem, HDWalletCoinStorage, HDWalletStorageError, HDWalletStorageResult};
+use crate::utxo::utxo_block_header_storage::BlockHeaderStorageError;
+use utxo_block_header_storage::BlockHeaderStorage;
+#[cfg(not(target_arch = "wasm32"))] pub mod tx_cache;
+#[cfg(target_arch = "wasm32")]
+pub mod utxo_indexedb_block_header_storage;
+#[cfg(not(target_arch = "wasm32"))]
+pub mod utxo_sql_block_header_storage;
 
 #[cfg(test)] pub mod utxo_tests;
 #[cfg(target_arch = "wasm32")] pub mod utxo_wasm_tests;
@@ -510,6 +517,7 @@ pub struct UtxoCoinFields {
     pub history_sync_state: Mutex<HistorySyncState>,
     /// Path to the TX cache directory
     pub tx_cache_directory: Option<PathBuf>,
+    pub block_headers_storage: Option<BlockHeaderStorage>,
     /// The cache of recently send transactions used to track the spent UTXOs and replace them with new outputs
     /// The daemon needs some time to update the listunspent list for address which makes it return already spent UTXOs
     /// This cache helps to prevent UTXO reuse in such cases
@@ -545,6 +553,56 @@ impl From<UnsupportedAddr> for WithdrawError {
     fn from(e: UnsupportedAddr) -> Self { WithdrawError::InvalidAddress(e.to_string()) }
 }
 
+#[derive(Debug)]
+pub enum GetTxHeightError {
+    HeightNotFound,
+}
+
+impl From<GetTxHeightError> for SPVError {
+    fn from(e: GetTxHeightError) -> Self {
+        match e {
+            GetTxHeightError::HeightNotFound => SPVError::InvalidHeight,
+        }
+    }
+}
+
+#[derive(Debug)]
+pub enum GetBlockHeaderError {
+    StorageError(BlockHeaderStorageError),
+    RpcError(JsonRpcError),
+    SerializationError(serialization::Error),
+    InvalidResponse(String),
+    SPVError(SPVError),
+    NativeNotSupported(String),
+    Internal(String),
+}
+
+impl From<JsonRpcError> for GetBlockHeaderError {
+    fn from(err: JsonRpcError) -> Self { GetBlockHeaderError::RpcError(err) }
+}
+
+impl From<UtxoRpcError> for GetBlockHeaderError {
+    fn from(e: UtxoRpcError) -> Self {
+        match e {
+            UtxoRpcError::Transport(e) | UtxoRpcError::ResponseParseError(e) => GetBlockHeaderError::RpcError(e),
+            UtxoRpcError::InvalidResponse(e) => GetBlockHeaderError::InvalidResponse(e),
+            UtxoRpcError::Internal(e) => GetBlockHeaderError::Internal(e),
+        }
+    }
+}
+
+impl From<SPVError> for GetBlockHeaderError {
+    fn from(e: SPVError) -> Self { GetBlockHeaderError::SPVError(e) }
+}
+
+impl From<serialization::Error> for GetBlockHeaderError {
+    fn from(err: serialization::Error) -> Self { GetBlockHeaderError::SerializationError(err) }
+}
+
+impl From<BlockHeaderStorageError> for GetBlockHeaderError {
+    fn from(err: BlockHeaderStorageError) -> Self { GetBlockHeaderError::StorageError(err) }
+}
+
 impl UtxoCoinFields {
     pub fn transaction_preimage(&self) -> TransactionInputSigner {
         let lock_time = if self.conf.ticker == "KMD" {
@@ -1031,6 +1089,14 @@ pub struct UtxoMergeParams {
     pub max_merge_at_once: usize,
 }
 
+#[derive(Clone, Debug, Deserialize, Serialize)]
+pub struct UtxoBlockHeaderVerificationParams {
+    pub difficulty_check: bool,
+    pub constant_difficulty: bool,
+    pub blocks_limit_to_check: NonZeroU64,
+    pub check_every: f64,
+}
+
 #[derive(Clone, Debug, Deserialize, Serialize)]
 pub struct UtxoActivationParams {
     pub mode: UtxoRpcMode,
@@ -1053,6 +1119,7 @@ pub enum UtxoFromLegacyReqErr {
     UnexpectedMethod,
     InvalidElectrumServers(json::Error),
     InvalidMergeParams(json::Error),
+    InvalidBlockHeaderVerificationParams(json::Error),
     InvalidRequiredConfs(json::Error),
     InvalidRequiresNota(json::Error),
     InvalidAddressFormat(json::Error),
diff --git a/mm2src/coins/utxo/qtum_delegation.rs b/mm2src/coins/utxo/qtum_delegation.rs
index 422cf36376..fd1ad33d94 100644
--- a/mm2src/coins/utxo/qtum_delegation.rs
+++ b/mm2src/coins/utxo/qtum_delegation.rs
@@ -124,14 +124,13 @@ impl QtumCoin {
         let delegation_output = self.remove_delegation_output(QRC20_GAS_LIMIT_DEFAULT, QRC20_GAS_PRICE_DEFAULT)?;
         let outputs = vec![delegation_output];
         let my_address = self.my_address().map_to_mm(DelegationError::InternalError)?;
-        Ok(self
-            .generate_delegation_transaction(
-                outputs,
-                my_address,
-                QRC20_GAS_LIMIT_DEFAULT,
-                TransactionType::RemoveDelegation,
-            )
-            .await?)
+        self.generate_delegation_transaction(
+            outputs,
+            my_address,
+            QRC20_GAS_LIMIT_DEFAULT,
+            TransactionType::RemoveDelegation,
+        )
+        .await
     }
 
     async fn am_i_currently_staking(&self) -> Result<Option<String>, MmError<StakingInfosError>> {
@@ -252,14 +251,13 @@ impl QtumCoin {
 
         let outputs = vec![delegation_output];
         let my_address = self.my_address().map_to_mm(DelegationError::InternalError)?;
-        Ok(self
-            .generate_delegation_transaction(
-                outputs,
-                my_address,
-                QRC20_GAS_LIMIT_DELEGATION,
-                TransactionType::StakingDelegation,
-            )
-            .await?)
+        self.generate_delegation_transaction(
+            outputs,
+            my_address,
+            QRC20_GAS_LIMIT_DELEGATION,
+            TransactionType::StakingDelegation,
+        )
+        .await
     }
 
     async fn generate_delegation_transaction(
diff --git a/mm2src/coins/utxo/rpc_clients.rs b/mm2src/coins/utxo/rpc_clients.rs
index 11a65c3976..6b1f837b94 100644
--- a/mm2src/coins/utxo/rpc_clients.rs
+++ b/mm2src/coins/utxo/rpc_clients.rs
@@ -1025,7 +1025,7 @@ impl Into<BlockHeaderNonce> for ElectrumNonce {
 
 #[derive(Debug, Deserialize)]
 pub struct ElectrumBlockHeadersRes {
-    count: u64,
+    pub count: u64,
     pub hex: BytesJson,
     #[allow(dead_code)]
     max: u64,
@@ -1044,8 +1044,8 @@ pub struct ElectrumBlockHeaderV12 {
 }
 
 impl ElectrumBlockHeaderV12 {
-    pub fn hash(&self) -> H256Json {
-        let block_header = BlockHeader {
+    fn as_block_header(&self) -> BlockHeader {
+        BlockHeader {
             version: self.version as u32,
             previous_header_hash: self.prev_block_hash.into(),
             merkle_root_hash: self.merkle_root.into(),
@@ -1064,7 +1064,17 @@ impl ElectrumBlockHeaderV12 {
             n_height: None,
             n_nonce_u64: None,
             mix_hash: None,
-        };
+        }
+    }
+
+    pub fn as_hex(&self) -> String {
+        let block_header = self.as_block_header();
+        let serialized = serialize(&block_header);
+        hex::encode(serialized)
+    }
+
+    pub fn hash(&self) -> H256Json {
+        let block_header = self.as_block_header();
         BlockHeader::hash(&block_header).into()
     }
 }
@@ -1658,6 +1668,49 @@ impl ElectrumClient {
         rpc_func!(self, "blockchain.block.headers", start_height, count)
     }
 
+    pub fn retrieve_last_headers(
+        &self,
+        blocks_limit_to_check: NonZeroU64,
+        block_height: u64,
+    ) -> UtxoRpcFut<(HashMap<u64, BlockHeader>, Vec<BlockHeader>)> {
+        let (from, count) = {
+            let from = if block_height < blocks_limit_to_check.get() {
+                0
+            } else {
+                block_height - blocks_limit_to_check.get()
+            };
+            (from, blocks_limit_to_check)
+        };
+        Box::new(
+            self.blockchain_block_headers(from, count)
+                .map_to_mm_fut(UtxoRpcError::from)
+                .and_then(move |headers| {
+                    let (block_registry, block_headers) = {
+                        if headers.count == 0 {
+                            return MmError::err(UtxoRpcError::Internal("No headers available".to_string()));
+                        }
+                        let len = CompactInteger::from(headers.count);
+                        let mut serialized = serialize(&len).take();
+                        serialized.extend(headers.hex.0.into_iter());
+                        let mut reader = Reader::new_with_coin_variant(serialized.as_slice(), CoinVariant::Standard);
+                        let maybe_block_headers = reader.read_list::<BlockHeader>();
+                        let block_headers = match maybe_block_headers {
+                            Ok(headers) => headers,
+                            Err(e) => return MmError::err(UtxoRpcError::InvalidResponse(format!("{:?}", e))),
+                        };
+                        let mut block_registry: HashMap<u64, BlockHeader> = HashMap::new();
+                        let mut starting_height = from;
+                        for block_header in &block_headers {
+                            block_registry.insert(starting_height, block_header.clone());
+                            starting_height += 1;
+                        }
+                        (block_registry, block_headers)
+                    };
+                    Ok((block_registry, block_headers))
+                }),
+        )
+    }
+
     /// https://electrumx.readthedocs.io/en/latest/protocol-methods.html#blockchain-transaction-get-merkle
     pub fn blockchain_transaction_get_merkle(&self, txid: H256Json, height: u64) -> RpcRes<TxMerkleBranch> {
         rpc_func!(self, "blockchain.transaction.get_merkle", txid, height)
diff --git a/mm2src/coins/utxo/slp.rs b/mm2src/coins/utxo/slp.rs
index 26de7ce3ba..dbe3c428b5 100644
--- a/mm2src/coins/utxo/slp.rs
+++ b/mm2src/coins/utxo/slp.rs
@@ -293,6 +293,17 @@ pub struct SlpProtocolConf {
     pub required_confirmations: Option<u64>,
 }
 
+#[derive(Debug)]
+pub struct ValidateHtlcInput {
+    tx: Vec<u8>,
+    other_pub: Public,
+    my_pub: Public,
+    time_lock: u32,
+    secret_hash: Vec<u8>,
+    amount: BigDecimal,
+    confirmations: u64,
+}
+
 impl SlpToken {
     pub fn new(
         decimals: u8,
@@ -433,22 +444,14 @@ impl SlpToken {
         .await
     }
 
-    async fn validate_htlc(
-        &self,
-        tx: &[u8],
-        other_pub: &Public,
-        my_pub: &Public,
-        time_lock: u32,
-        secret_hash: &[u8],
-        amount: BigDecimal,
-    ) -> Result<(), MmError<ValidateHtlcError>> {
-        let mut tx: UtxoTx = deserialize(tx).map_to_mm(ValidateHtlcError::TxParseError)?;
+    async fn validate_htlc(&self, input: ValidateHtlcInput) -> Result<(), MmError<ValidateHtlcError>> {
+        let mut tx: UtxoTx = deserialize(input.tx.as_slice()).map_to_mm(ValidateHtlcError::TxParseError)?;
         tx.tx_hash_algo = self.platform_coin.as_ref().tx_hash_algo;
         if tx.outputs.len() < 2 {
             return MmError::err(ValidateHtlcError::TxLackOfOutputs);
         }
 
-        let slp_satoshis = sat_from_big_decimal(&amount, self.decimals())?;
+        let slp_satoshis = sat_from_big_decimal(&input.amount, self.decimals())?;
 
         let slp_unspent = SlpUnspent {
             bch_unspent: UnspentInfo {
@@ -486,11 +489,12 @@ impl SlpToken {
             self.platform_coin.clone(),
             tx,
             SLP_SWAP_VOUT,
-            other_pub,
-            my_pub,
-            secret_hash,
+            &input.other_pub,
+            &input.my_pub,
+            &input.secret_hash,
             self.platform_dust_dec(),
-            time_lock,
+            input.time_lock,
+            input.confirmations,
         );
 
         validate_fut
@@ -1342,13 +1346,20 @@ impl SwapOps for SlpToken {
         let secret_hash = input.secret_hash.to_owned();
         let time_lock = input.time_lock;
         let amount = input.amount;
+        let confirmations = input.confirmations;
 
         let coin = self.clone();
+        let input = ValidateHtlcInput {
+            tx,
+            other_pub: maker_pub,
+            my_pub: taker_pub,
+            time_lock,
+            secret_hash,
+            amount,
+            confirmations,
+        };
         let fut = async move {
-            try_s!(
-                coin.validate_htlc(&tx, &maker_pub, &taker_pub, time_lock, &secret_hash, amount)
-                    .await
-            );
+            try_s!(coin.validate_htlc(input).await);
             Ok(())
         };
         Box::new(fut.boxed().compat())
@@ -1357,20 +1368,20 @@ impl SwapOps for SlpToken {
     fn validate_taker_payment(&self, input: ValidatePaymentInput) -> Box<dyn Future<Item = (), Error = String> + Send> {
         let taker_pub = try_fus!(Public::from_slice(&input.taker_pub));
         let maker_pub = try_fus!(Public::from_slice(&input.maker_pub));
+        let confirmations = input.confirmations;
 
         let coin = self.clone();
+        let input = ValidateHtlcInput {
+            tx: input.payment_tx,
+            other_pub: taker_pub,
+            my_pub: maker_pub,
+            time_lock: input.time_lock,
+            secret_hash: input.secret_hash,
+            amount: input.amount,
+            confirmations,
+        };
         let fut = async move {
-            try_s!(
-                coin.validate_htlc(
-                    &input.payment_tx,
-                    &taker_pub,
-                    &maker_pub,
-                    input.time_lock,
-                    &input.secret_hash,
-                    input.amount
-                )
-                .await
-            );
+            try_s!(coin.validate_htlc(input).await);
             Ok(())
         };
         Box::new(fut.boxed().compat())
@@ -1943,9 +1954,17 @@ mod slp_tests {
 
         let lock_time = 1624547837;
         let secret_hash = hex::decode("5d9e149ad9ccb20e9f931a69b605df2ffde60242").unwrap();
-        let amount = "0.1".parse().unwrap();
-
-        block_on(fusd.validate_htlc(&tx, &other_pub, &my_pub, lock_time, &secret_hash, amount)).unwrap();
+        let amount: BigDecimal = "0.1".parse().unwrap();
+        let input = ValidateHtlcInput {
+            tx,
+            other_pub,
+            my_pub,
+            time_lock: lock_time,
+            secret_hash,
+            amount,
+            confirmations: 1,
+        };
+        block_on(fusd.validate_htlc(input)).unwrap();
     }
 
     #[test]
@@ -2040,12 +2059,21 @@ mod slp_tests {
             &secret_hash,
             fusd.platform_dust_dec(),
             lock_time,
+            1,
         )
         .wait()
         .unwrap();
 
-        let validity_err =
-            block_on(fusd.validate_htlc(&tx, &other_pub, my_pub, lock_time, &secret_hash, amount)).unwrap_err();
+        let input = ValidateHtlcInput {
+            tx,
+            other_pub,
+            my_pub: my_pub.clone(),
+            time_lock: lock_time,
+            secret_hash,
+            amount,
+            confirmations: 1,
+        };
+        let validity_err = block_on(fusd.validate_htlc(input)).unwrap_err();
         match validity_err.into_inner() {
             ValidateHtlcError::InvalidSlpUtxo(e) => println!("{:?}", e),
             err @ _ => panic!("Unexpected err {:?}", err),
diff --git a/mm2src/coins/utxo/utxo_block_header_storage.rs b/mm2src/coins/utxo/utxo_block_header_storage.rs
new file mode 100644
index 0000000000..ada1453824
--- /dev/null
+++ b/mm2src/coins/utxo/utxo_block_header_storage.rs
@@ -0,0 +1,151 @@
+use crate::utxo::rpc_clients::ElectrumBlockHeader;
+#[cfg(target_arch = "wasm32")]
+use crate::utxo::utxo_indexedb_block_header_storage::IndexedDBBlockHeadersStorage;
+#[cfg(not(target_arch = "wasm32"))]
+use crate::utxo::utxo_sql_block_header_storage::SqliteBlockHeadersStorage;
+use crate::utxo::UtxoBlockHeaderVerificationParams;
+use async_trait::async_trait;
+use chain::BlockHeader;
+use common::mm_ctx::MmArc;
+use common::mm_error::MmError;
+use derive_more::Display;
+use std::collections::HashMap;
+use std::fmt::{Debug, Formatter};
+
+#[derive(Debug, Display)]
+pub enum BlockHeaderStorageError {
+    #[display(fmt = "Can't add to the storage for {} - reason: {}", ticker, reason)]
+    AddToStorageError { ticker: String, reason: String },
+    #[display(fmt = "Can't get from the storage for {} - reason: {}", ticker, reason)]
+    GetFromStorageError { ticker: String, reason: String },
+    #[display(
+        fmt = "Can't retrieve the table from the storage for {} - reason: {}",
+        ticker,
+        reason
+    )]
+    CantRetrieveTableError { ticker: String, reason: String },
+    #[display(fmt = "Can't query from the storage - query: {} - reason: {}", query, reason)]
+    QueryError { query: String, reason: String },
+    #[display(fmt = "Can't init from the storage - ticker: {} - reason: {}", ticker, reason)]
+    InitializationError { ticker: String, reason: String },
+    #[display(fmt = "Can't decode/deserialize from storage for {} - reason: {}", ticker, reason)]
+    DecodeError { ticker: String, reason: String },
+}
+
+pub struct BlockHeaderStorage {
+    pub inner: Box<dyn BlockHeaderStorageOps>,
+    pub params: UtxoBlockHeaderVerificationParams,
+}
+
+impl Debug for BlockHeaderStorage {
+    fn fmt(&self, _f: &mut Formatter<'_>) -> std::fmt::Result { Ok(()) }
+}
+
+pub trait InitBlockHeaderStorageOps: Send + Sync + 'static {
+    fn new_from_ctx(ctx: MmArc, params: UtxoBlockHeaderVerificationParams) -> Option<BlockHeaderStorage>
+    where
+        Self: Sized;
+}
+
+#[async_trait]
+pub trait BlockHeaderStorageOps: Send + Sync + 'static {
+    /// Initializes collection/tables in storage for a specified coin
+    async fn init(&self, for_coin: &str) -> Result<(), MmError<BlockHeaderStorageError>>;
+
+    async fn is_initialized_for(&self, for_coin: &str) -> Result<bool, MmError<BlockHeaderStorageError>>;
+
+    // Adds multiple block headers to the selected coin's header storage
+    // Should store it as `TICKER_HEIGHT=hex_string`
+    // use this function for headers that comes from `blockchain_headers_subscribe`
+    async fn add_electrum_block_headers_to_storage(
+        &self,
+        for_coin: &str,
+        headers: Vec<ElectrumBlockHeader>,
+    ) -> Result<(), MmError<BlockHeaderStorageError>>;
+
+    // Adds multiple block headers to the selected coin's header storage
+    // Should store it as `TICKER_HEIGHT=hex_string`
+    // use this function for headers that comes from `blockchain_block_headers`
+    async fn add_block_headers_to_storage(
+        &self,
+        for_coin: &str,
+        headers: HashMap<u64, BlockHeader>,
+    ) -> Result<(), MmError<BlockHeaderStorageError>>;
+
+    /// Gets the block header by height from the selected coin's storage as BlockHeader
+    async fn get_block_header(
+        &self,
+        for_coin: &str,
+        height: u64,
+    ) -> Result<Option<BlockHeader>, MmError<BlockHeaderStorageError>>;
+
+    /// Gets the block header by height from the selected coin's storage as hex
+    async fn get_block_header_raw(
+        &self,
+        for_coin: &str,
+        height: u64,
+    ) -> Result<Option<String>, MmError<BlockHeaderStorageError>>;
+}
+
+impl InitBlockHeaderStorageOps for BlockHeaderStorage {
+    #[cfg(not(target_arch = "wasm32"))]
+    fn new_from_ctx(ctx: MmArc, params: UtxoBlockHeaderVerificationParams) -> Option<BlockHeaderStorage> {
+        ctx.sqlite_connection.as_option().map(|connection| BlockHeaderStorage {
+            inner: Box::new(SqliteBlockHeadersStorage(connection.clone())),
+            params,
+        })
+    }
+
+    #[cfg(target_arch = "wasm32")]
+    fn new_from_ctx(_ctx: MmArc, params: UtxoBlockHeaderVerificationParams) -> Option<BlockHeaderStorage> {
+        Some(BlockHeaderStorage {
+            inner: Box::new(IndexedDBBlockHeadersStorage {}),
+            params,
+        })
+    }
+}
+
+#[async_trait]
+impl BlockHeaderStorageOps for BlockHeaderStorage {
+    async fn init(&self, for_coin: &str) -> Result<(), MmError<BlockHeaderStorageError>> {
+        self.inner.init(for_coin).await
+    }
+
+    async fn is_initialized_for(&self, for_coin: &str) -> Result<bool, MmError<BlockHeaderStorageError>> {
+        self.inner.is_initialized_for(for_coin).await
+    }
+
+    async fn add_electrum_block_headers_to_storage(
+        &self,
+        for_coin: &str,
+        headers: Vec<ElectrumBlockHeader>,
+    ) -> Result<(), MmError<BlockHeaderStorageError>> {
+        self.inner
+            .add_electrum_block_headers_to_storage(for_coin, headers)
+            .await
+    }
+
+    async fn add_block_headers_to_storage(
+        &self,
+        for_coin: &str,
+        headers: HashMap<u64, BlockHeader>,
+    ) -> Result<(), MmError<BlockHeaderStorageError>> {
+        self.inner.add_block_headers_to_storage(for_coin, headers).await
+    }
+
+    async fn get_block_header(
+        &self,
+        for_coin: &str,
+        height: u64,
+    ) -> Result<Option<BlockHeader>, MmError<BlockHeaderStorageError>> {
+        self.inner.get_block_header(for_coin, height).await
+    }
+
+    async fn get_block_header_raw(
+        &self,
+        for_coin: &str,
+        height: u64,
+    ) -> Result<Option<String>, MmError<BlockHeaderStorageError>> {
+        self.inner.get_block_header_raw(for_coin, height).await
+    }
+}
diff --git a/mm2src/coins/utxo/utxo_builder/utxo_arc_builder.rs b/mm2src/coins/utxo/utxo_builder/utxo_arc_builder.rs
index 5464f59141..7324767562 100644
--- a/mm2src/coins/utxo/utxo_builder/utxo_arc_builder.rs
+++ b/mm2src/coins/utxo/utxo_builder/utxo_arc_builder.rs
@@ -1,6 +1,7 @@
+use crate::utxo::utxo_block_header_storage::BlockHeaderStorage;
 use crate::utxo::utxo_builder::{UtxoCoinBuildError, UtxoCoinBuilder, UtxoCoinBuilderCommonOps,
                                 UtxoFieldsWithHardwareWalletBuilder, UtxoFieldsWithIguanaPrivKeyBuilder};
-use crate::utxo::utxo_common::merge_utxo_loop;
+use crate::utxo::utxo_common::{block_header_utxo_loop, merge_utxo_loop};
 use crate::utxo::{UtxoArc, UtxoCoinFields, UtxoCommonOps, UtxoWeak};
 use crate::{PrivKeyBuildPolicy, UtxoActivationParams};
 use async_trait::async_trait;
@@ -8,6 +9,7 @@ use common::executor::spawn;
 use common::log::info;
 use common::mm_ctx::MmArc;
 use common::mm_error::prelude::*;
+use futures::future::{abortable, AbortHandle};
 use serde_json::Value as Json;
 
 pub struct UtxoArcBuilder<'a, F, T>
@@ -86,7 +88,14 @@ where
         let utxo_weak = utxo_arc.downgrade();
         let result_coin = (self.constructor)(utxo_arc);
 
-        self.spawn_merge_utxo_loop_if_required(utxo_weak, self.constructor.clone());
+        self.spawn_merge_utxo_loop_if_required(utxo_weak.clone(), self.constructor.clone());
+        if let Some(abort_handler) = self.spawn_block_header_utxo_loop_if_required(
+            utxo_weak,
+            &result_coin.as_ref().block_headers_storage,
+            self.constructor.clone(),
+        ) {
+            self.ctx.abort_handlers.lock().unwrap().push(abort_handler);
+        }
         Ok(result_coin)
     }
 }
@@ -98,6 +107,13 @@ where
 {
 }
 
+impl<'a, F, T> BlockHeaderUtxoArcOps<T> for UtxoArcBuilder<'a, F, T>
+where
+    F: Fn(UtxoArc) -> T + Send + Sync + 'static,
+    T: AsRef<UtxoCoinFields> + UtxoCommonOps + Send + Sync + 'static,
+{
+}
+
 pub trait MergeUtxoArcOps<T>: UtxoCoinBuilderCommonOps
 where
     T: AsRef<UtxoCoinFields> + UtxoCommonOps + Send + Sync + 'static,
@@ -119,3 +135,34 @@ where
         }
     }
 }
+
+pub trait BlockHeaderUtxoArcOps<T>: UtxoCoinBuilderCommonOps
+where
+    T: AsRef<UtxoCoinFields> + UtxoCommonOps + Send + Sync + 'static,
+{
+    fn spawn_block_header_utxo_loop_if_required<F>(
+        &self,
+        weak: UtxoWeak,
+        maybe_storage: &Option<BlockHeaderStorage>,
+        constructor: F,
+    ) -> Option<AbortHandle>
+    where
+        F: Fn(UtxoArc) -> T + Send + Sync + 'static,
+    {
+        if maybe_storage.is_some() {
+            let ticker = self.ticker().to_owned();
+            let (fut, abort_handle) = abortable(block_header_utxo_loop(weak, constructor));
+            info!("Starting UTXO block header loop for coin {}", ticker);
+            spawn(async move {
+                if let Err(e) = fut.await {
+                    info!(
+                        "spawn_block_header_utxo_loop_if_required stopped for {}, reason {}",
+                        ticker, e
+                    );
+                }
+            });
+            return Some(abort_handle);
+        }
+        None
+    }
+}
diff --git a/mm2src/coins/utxo/utxo_builder/utxo_coin_builder.rs b/mm2src/coins/utxo/utxo_builder/utxo_coin_builder.rs
index 332114588e..97e60a7774 100644
--- a/mm2src/coins/utxo/utxo_builder/utxo_coin_builder.rs
+++ b/mm2src/coins/utxo/utxo_builder/utxo_coin_builder.rs
@@ -2,6 +2,7 @@ use crate::hd_wallet::{HDAccountsMap, HDAccountsMutex};
 use crate::hd_wallet_storage::{HDWalletCoinStorage, HDWalletStorageError};
 use crate::utxo::rpc_clients::{ElectrumClient, ElectrumClientImpl, ElectrumRpcRequest, EstimateFeeMethod,
                                UtxoRpcClientEnum};
+use crate::utxo::utxo_block_header_storage::{BlockHeaderStorage, InitBlockHeaderStorageOps};
 use crate::utxo::utxo_builder::utxo_conf_builder::{UtxoConfBuilder, UtxoConfError, UtxoConfResult};
 use crate::utxo::{output_script, utxo_common, ElectrumBuilderArgs, ElectrumProtoVerifier, RecentlySpentOutPoints,
                   TxFee, UtxoCoinFields, UtxoHDAccount, UtxoHDWallet, UtxoRpcMode, DEFAULT_GAP_LIMIT, UTXO_DUST_AMOUNT};
@@ -163,6 +164,7 @@ pub trait UtxoFieldsWithIguanaPrivKeyBuilder: UtxoCoinBuilderCommonOps {
         let tx_cache_directory = Some(self.ctx().dbdir().join("TX_CACHE"));
         let tx_hash_algo = self.tx_hash_algo();
         let check_utxo_maturity = self.check_utxo_maturity();
+        let block_headers_storage = self.block_headers_storage()?;
 
         let coin = UtxoCoinFields {
             conf,
@@ -173,6 +175,7 @@ pub trait UtxoFieldsWithIguanaPrivKeyBuilder: UtxoCoinBuilderCommonOps {
             derivation_method,
             history_sync_state: Mutex::new(initial_history_state),
             tx_cache_directory,
+            block_headers_storage,
             recently_spent_outpoints: AsyncMutex::new(RecentlySpentOutPoints::new(my_script_pubkey)),
             tx_fee,
             tx_hash_algo,
@@ -219,6 +222,7 @@ pub trait UtxoFieldsWithHardwareWalletBuilder: UtxoCoinBuilderCommonOps {
         let tx_cache_directory = Some(self.ctx().dbdir().join("TX_CACHE"));
         let tx_hash_algo = self.tx_hash_algo();
         let check_utxo_maturity = self.check_utxo_maturity();
+        let block_headers_storage = self.block_headers_storage()?;
 
         let coin = UtxoCoinFields {
             conf,
@@ -228,6 +232,7 @@ pub trait UtxoFieldsWithHardwareWalletBuilder: UtxoCoinBuilderCommonOps {
             priv_key_policy: PrivKeyPolicy::HardwareWallet,
             derivation_method: DerivationMethod::HDWallet(hd_wallet),
             history_sync_state: Mutex::new(initial_history_state),
+            block_headers_storage,
             tx_cache_directory,
             recently_spent_outpoints,
             tx_fee,
@@ -268,6 +273,15 @@ pub trait UtxoCoinBuilderCommonOps {
 
     fn ticker(&self) -> &str;
 
+    fn block_headers_storage(&self) -> UtxoCoinBuildResult<Option<BlockHeaderStorage>> {
+        let params: Option<_> = json::from_value(self.conf()["block_header_params"].clone())
+            .map_to_mm(|e| UtxoConfError::InvalidBlockHeaderParams(e.to_string()))?;
+        match params {
+            None => Ok(None),
+            Some(params) => Ok(BlockHeaderStorage::new_from_ctx(self.ctx().clone(), params)),
+        }
+    }
+
     fn address_format(&self) -> UtxoCoinBuildResult<UtxoAddressFormat> {
         let format_from_req = self.activation_params().address_format.clone();
         let format_from_conf = json::from_value::<Option<UtxoAddressFormat>>(self.conf()["address_format"].clone())
diff --git a/mm2src/coins/utxo/utxo_builder/utxo_conf_builder.rs b/mm2src/coins/utxo/utxo_builder/utxo_conf_builder.rs
index 59d141fef8..451ccc19e9 100644
--- a/mm2src/coins/utxo/utxo_builder/utxo_conf_builder.rs
+++ b/mm2src/coins/utxo/utxo_builder/utxo_conf_builder.rs
@@ -40,6 +40,7 @@ pub enum UtxoConfError {
     InvalidConsensusBranchId(String),
     InvalidVersionGroupId(String),
     InvalidAddressFormat(String),
+    InvalidBlockHeaderParams(String),
     InvalidDecimals(String),
 }
 
diff --git a/mm2src/coins/utxo/utxo_common.rs b/mm2src/coins/utxo/utxo_common.rs
index 7d1b4b385c..218f8c65a7 100644
--- a/mm2src/coins/utxo/utxo_common.rs
+++ b/mm2src/coins/utxo/utxo_common.rs
@@ -14,10 +14,10 @@ use crate::{CanRefundHtlc, CoinBalance, CoinWithDerivationMethod, GetWithdrawSen
 use bigdecimal::{BigDecimal, Zero};
 pub use bitcrypto::{dhash160, sha256, ChecksumType};
 use chain::constants::SEQUENCE_FINAL;
-use chain::{OutPoint, TransactionOutput};
+use chain::{BlockHeader, OutPoint, RawBlockHeader, TransactionOutput};
 use common::executor::Timer;
 use common::jsonrpc_client::JsonRpcErrorType;
-use common::log::{error, info, warn};
+use common::log::{debug, error, info, warn};
 use common::mm_ctx::MmArc;
 use common::mm_error::prelude::*;
 use common::mm_metrics::MetricsArc;
@@ -35,11 +35,16 @@ use rpc::v1::types::{Bytes as BytesJson, TransactionInputEnum, H256 as H256Json}
 use script::{Builder, Opcode, Script, ScriptAddress, TransactionInputSigner, UnsignedTransactionInput};
 use secp256k1::{PublicKey, Signature};
 use serde_json::{self as json};
-use serialization::{deserialize, serialize, serialize_with_flags, CoinVariant, SERIALIZE_TRANSACTION_WITNESS};
+use serialization::{deserialize, serialize, serialize_list, serialize_with_flags, CoinVariant,
+                    SERIALIZE_TRANSACTION_WITNESS};
+use spv_validation::helpers_validation::validate_headers;
+use spv_validation::spv_proof::SPVProof;
+use spv_validation::types::SPVError;
 use std::cmp::Ordering;
 use std::collections::hash_map::{Entry, HashMap};
 use std::str::FromStr;
 use std::sync::atomic::Ordering as AtomicOrdering;
+use utxo_block_header_storage::BlockHeaderStorageOps;
 use utxo_signer::with_key_pair::p2sh_spend;
 use utxo_signer::UtxoSignerOps;
 
@@ -67,6 +72,19 @@ lazy_static! {
 
 pub const HISTORY_TOO_LARGE_ERR_CODE: i64 = -1;
 
+fn ten_f64() -> f64 { 10. }
+
+fn one_hundred() -> usize { 100 }
+
+#[derive(Clone, Debug, Deserialize, Serialize)]
+pub struct UtxoMergeParams {
+    merge_at: usize,
+    #[serde(default = "ten_f64")]
+    check_every: f64,
+    #[serde(default = "one_hundred")]
+    max_merge_at_once: usize,
+}
+
 pub async fn get_tx_fee(coin: &UtxoCoinFields) -> UtxoRpcResult<ActualTxFee> {
     let conf = &coin.conf;
     match &coin.tx_fee {
@@ -1475,6 +1493,7 @@ where
         &input.secret_hash,
         input.amount,
         input.time_lock,
+        input.confirmations,
     )
 }
 
@@ -1498,6 +1517,7 @@ where
         &input.secret_hash,
         input.amount,
         input.time_lock,
+        input.confirmations,
     )
 }
 
@@ -2991,6 +3011,60 @@ pub fn address_from_pubkey(
     }
 }
 
+pub async fn validate_spv_proof<T>(coin: T, tx: UtxoTx) -> Result<(), MmError<SPVError>>
+where
+    T: AsRef<UtxoCoinFields> + Send + Sync + 'static,
+{
+    let client = match &coin.as_ref().rpc_client {
+        UtxoRpcClientEnum::Native(_) => return Ok(()),
+        UtxoRpcClientEnum::Electrum(electrum_client) => electrum_client,
+    };
+    if tx.outputs.is_empty() {
+        return MmError::err(SPVError::InvalidVout);
+    }
+    let height = get_tx_height(&tx, client).await?;
+    let block_header = block_header_from_storage_or_rpc(&coin, height, &coin.as_ref().block_headers_storage)
+        .await
+        .map_err(|_e| SPVError::UnableToGetHeader)?;
+    let raw_header = RawBlockHeader::new(block_header.raw().take())?;
+
+    let merkle_branch = client
+        .blockchain_transaction_get_merkle(tx.hash().reversed().into(), height)
+        .compat()
+        .await
+        .map_to_mm(|_e| SPVError::UnableToGetMerkle)?;
+    let intermediate_nodes: Vec<H256> = merkle_branch
+        .merkle
+        .into_iter()
+        .map(|hash| hash.reversed().into())
+        .collect();
+    let proof = SPVProof {
+        tx_id: tx.hash(),
+        vin: serialize_list(&tx.inputs).take(),
+        vout: serialize_list(&tx.outputs).take(),
+        index: merkle_branch.pos as u64,
+        confirming_header: block_header,
+        raw_header,
+        intermediate_nodes,
+    };
+    proof.validate().map_err(MmError::new)
+}
+
+pub async fn get_tx_height(tx: &UtxoTx, client: &ElectrumClient) -> Result<u64, MmError<GetTxHeightError>> {
+    for output in tx.outputs.clone() {
+        let script_pubkey_str = hex::encode(electrum_script_hash(&output.script_pubkey));
+        if let Ok(history) = client.scripthash_get_history(script_pubkey_str.as_str()).compat().await {
+            if let Some(item) = history
+                .into_iter()
+                .find(|item| item.tx_hash.reversed() == H256Json(*tx.hash()) && item.height > 0)
+            {
+                return Ok(item.height as u64);
+            }
+        }
+    }
+    MmError::err(GetTxHeightError::HeightNotFound)
+}
+
 #[allow(clippy::too_many_arguments)]
 pub fn validate_payment<T>(
     coin: T,
@@ -3001,6 +3075,7 @@ pub fn validate_payment<T>(
     priv_bn_hash: &[u8],
     amount: BigDecimal,
     time_lock: u32,
+    confirmations: u64,
 ) -> Box<dyn Future<Item = (), Error = String> + Send>
 where
     T: AsRef<UtxoCoinFields> + Send + Sync + 'static,
@@ -3056,7 +3131,10 @@ where
                     expected_output
                 );
             }
-            return Ok(());
+            return match confirmations {
+                0 => Ok(()),
+                _ => validate_spv_proof(coin, tx).await.map_err(|e| format!("{:?}", e)),
+            };
         }
     };
     Box::new(fut.boxed().compat())
@@ -3298,6 +3376,150 @@ fn increase_by_percent(num: u64, percent: f64) -> u64 {
     num + (percent.round() as u64)
 }
 
+pub async fn valid_block_header_from_storage<T>(
+    coin: &T,
+    height: u64,
+    storage: &BlockHeaderStorage,
+    client: &ElectrumClient,
+) -> Result<BlockHeader, MmError<GetBlockHeaderError>>
+where
+    T: AsRef<UtxoCoinFields>,
+{
+    match storage
+        .get_block_header(coin.as_ref().conf.ticker.as_str(), height)
+        .await?
+    {
+        None => {
+            let bytes = client.blockchain_block_header(height).compat().await?;
+            let header: BlockHeader = deserialize(bytes.0.as_slice())?;
+            let params = &storage.params;
+            let blocks_limit = params.blocks_limit_to_check;
+            let (headers_registry, headers) = client.retrieve_last_headers(blocks_limit, height).compat().await?;
+            match spv_validation::helpers_validation::validate_headers(
+                headers,
+                params.difficulty_check,
+                params.constant_difficulty,
+            ) {
+                Ok(_) => {
+                    storage
+                        .add_block_headers_to_storage(coin.as_ref().conf.ticker.as_str(), headers_registry)
+                        .await?;
+                    Ok(header)
+                },
+                Err(err) => MmError::err(GetBlockHeaderError::SPVError(err)),
+            }
+        },
+        Some(header) => Ok(header),
+    }
+}
+
+pub async fn block_header_from_storage_or_rpc<T>(
+    coin: &T,
+    height: u64,
+    storage: &Option<BlockHeaderStorage>,
+) -> Result<BlockHeader, MmError<GetBlockHeaderError>>
+where
+    T: AsRef<UtxoCoinFields>,
+{
+    let client = match &coin.as_ref().rpc_client {
+        UtxoRpcClientEnum::Native(_) => {
+            return MmError::err(GetBlockHeaderError::NativeNotSupported(
+                "Native client not supported".to_string(),
+            ))
+        },
+        UtxoRpcClientEnum::Electrum(client) => client,
+    };
+
+    match storage {
+        Some(ref storage) => valid_block_header_from_storage(&coin, height, storage, client).await,
+        None => Ok(deserialize(
+            client.blockchain_block_header(height).compat().await?.as_slice(),
+        )?),
+    }
+}
+
+macro_rules! try_loop_with_sleep {
+    ($e:expr, $delay: ident) => {
+        match $e {
+            Ok(res) => res,
+            Err(e) => {
+                error!("error {:?}", e);
+                Timer::sleep($delay).await;
+                continue;
+            },
+        }
+    };
+}
+
+pub async fn block_header_utxo_loop<T>(weak: UtxoWeak, constructor: impl Fn(UtxoArc) -> T)
+where
+    T: AsRef<UtxoCoinFields> + UtxoCommonOps,
+{
+    {
+        let coin = match weak.upgrade() {
+            Some(arc) => constructor(arc),
+            None => return,
+        };
+        let ticker = coin.as_ref().conf.ticker.as_str();
+        let storage = match &coin.as_ref().block_headers_storage {
+            None => return,
+            Some(storage) => storage,
+        };
+        match storage.is_initialized_for(ticker).await {
+            Ok(true) => info!("Block Header Storage already initialized for {}", ticker),
+            Ok(false) => {
+                if let Err(e) = storage.init(ticker).await {
+                    error!(
+                        "Couldn't initiate storage - aborting the block_header_utxo_loop: {:?}",
+                        e
+                    );
+                    return;
+                }
+                info!("Block Header Storage successfully initialized for {}", ticker);
+            },
+            Err(_e) => return,
+        };
+    }
+    while let Some(arc) = weak.upgrade() {
+        let coin = constructor(arc);
+        let storage = match &coin.as_ref().block_headers_storage {
+            None => break,
+            Some(storage) => storage,
+        };
+        let params = storage.params.clone();
+        let (check_every, blocks_limit_to_check, difficulty_check, constant_difficulty) = (
+            params.check_every,
+            params.blocks_limit_to_check,
+            params.difficulty_check,
+            params.constant_difficulty,
+        );
+        let height = try_loop_with_sleep!(coin.as_ref().rpc_client.get_block_count().compat().await, check_every);
+        let client = match &coin.as_ref().rpc_client {
+            UtxoRpcClientEnum::Native(_) => break,
+            UtxoRpcClientEnum::Electrum(client) => client,
+        };
+        let (block_registry, block_headers) = try_loop_with_sleep!(
+            client
+                .retrieve_last_headers(blocks_limit_to_check, height)
+                .compat()
+                .await,
+            check_every
+        );
+        try_loop_with_sleep!(
+            validate_headers(block_headers, difficulty_check, constant_difficulty),
+            check_every
+        );
+
+        let ticker = coin.as_ref().conf.ticker.as_str();
+        try_loop_with_sleep!(
+            storage.add_block_headers_to_storage(ticker, block_registry).await,
+            check_every
+        );
+        debug!("tick block_header_utxo_loop for {}", coin.as_ref().conf.ticker);
+        Timer::sleep(check_every).await;
+    }
+}
+
 pub async fn merge_utxo_loop<T>(
     weak: UtxoWeak,
     merge_at: usize,
diff --git a/mm2src/coins/utxo/utxo_indexedb_block_header_storage.rs b/mm2src/coins/utxo/utxo_indexedb_block_header_storage.rs
new file mode 100644
index 0000000000..4814aaeb6f
--- /dev/null
+++ b/mm2src/coins/utxo/utxo_indexedb_block_header_storage.rs
@@ -0,0 +1,49 @@
+use crate::utxo::rpc_clients::ElectrumBlockHeader;
+use crate::utxo::utxo_block_header_storage::BlockHeaderStorageError;
+use crate::utxo::utxo_block_header_storage::BlockHeaderStorageOps;
+use async_trait::async_trait;
+use chain::BlockHeader;
+use common::mm_error::MmError;
+use std::collections::HashMap;
+
+#[derive(Debug)]
+pub struct IndexedDBBlockHeadersStorage {}
+
+#[async_trait]
+impl BlockHeaderStorageOps for IndexedDBBlockHeadersStorage {
+    async fn init(&self, _for_coin: &str) -> Result<(), MmError<BlockHeaderStorageError>> { Ok(()) }
+
+    async fn is_initialized_for(&self, _for_coin: &str) -> Result<bool, MmError<BlockHeaderStorageError>> { Ok(true) }
+
+    async fn add_electrum_block_headers_to_storage(
+        &self,
+        _for_coin: &str,
+        _headers: Vec<ElectrumBlockHeader>,
+    ) -> Result<(), MmError<BlockHeaderStorageError>> {
+        Ok(())
+    }
+
+    async fn add_block_headers_to_storage(
+        &self,
+        _for_coin: &str,
+        _headers: HashMap<u64, BlockHeader>,
+    ) -> Result<(), MmError<BlockHeaderStorageError>> {
+        Ok(())
+    }
+
+    async fn get_block_header(
+        &self,
+        _for_coin: &str,
+        _height: u64,
+    ) -> Result<Option<BlockHeader>, MmError<BlockHeaderStorageError>> {
+        Ok(None)
+    }
+
+    async fn get_block_header_raw(
+        &self,
+        _for_coin: &str,
+        _height: u64,
+    ) -> Result<Option<String>, MmError<BlockHeaderStorageError>> {
+        Ok(None)
+    }
+}
diff --git a/mm2src/coins/utxo/utxo_sql_block_header_storage.rs b/mm2src/coins/utxo/utxo_sql_block_header_storage.rs
new file mode 100644
index 0000000000..75dfe4f4eb
--- /dev/null
+++ b/mm2src/coins/utxo/utxo_sql_block_header_storage.rs
@@ -0,0 +1,320 @@
+use crate::utxo::rpc_clients::ElectrumBlockHeader;
+use crate::utxo::utxo_block_header_storage::{BlockHeaderStorageError, BlockHeaderStorageOps};
+use async_trait::async_trait;
+use chain::BlockHeader;
+use common::async_blocking;
+use common::mm_error::MmError;
+use db_common::{sqlite::rusqlite::Error as SqlError,
+                sqlite::rusqlite::{Connection, Row, ToSql, NO_PARAMS},
+                sqlite::string_from_row,
+                sqlite::validate_table_name,
+                sqlite::CHECK_TABLE_EXISTS_SQL};
+use serialization::deserialize;
+use std::collections::HashMap;
+use std::sync::{Arc, Mutex};
+
+fn block_headers_cache_table(ticker: &str) -> String { ticker.to_owned() + "_block_headers_cache" }
+
+fn get_table_name_and_validate(for_coin: &str) -> Result<String, MmError<BlockHeaderStorageError>> {
+    let table_name = block_headers_cache_table(for_coin);
+    validate_table_name(&table_name).map_err(|e| BlockHeaderStorageError::CantRetrieveTableError {
+        ticker: for_coin.to_string(),
+        reason: e.to_string(),
+    })?;
+    Ok(table_name)
+}
+
+fn create_block_header_cache_table_sql(for_coin: &str) -> Result<String, MmError<BlockHeaderStorageError>> {
+    let table_name = get_table_name_and_validate(for_coin)?;
+    let sql = "CREATE TABLE IF NOT EXISTS ".to_owned()
+        + &table_name
+        + " (
+        block_height INTEGER NOT NULL UNIQUE,
+        hex TEXT NOT NULL
+    );";
+
+    Ok(sql)
+}
+
+fn insert_block_header_in_cache_sql(for_coin: &str) -> Result<String, MmError<BlockHeaderStorageError>> {
+    let table_name = get_table_name_and_validate(for_coin)?;
+    // We can simply ignore the repetitive attempt to insert the same block_height
+    let sql = "INSERT OR IGNORE INTO ".to_owned() + &table_name + " (block_height, hex) VALUES (?1, ?2);";
+    Ok(sql)
+}
+
+fn get_block_header_by_height(for_coin: &str) -> Result<String, MmError<BlockHeaderStorageError>> {
+    let table_name = get_table_name_and_validate(for_coin)?;
+    let sql = "SELECT hex FROM ".to_owned() + &table_name + " WHERE block_height=?1;";
+
+    Ok(sql)
+}
+
+#[derive(Clone, Debug)]
+pub struct SqliteBlockHeadersStorage(pub Arc<Mutex<Connection>>);
+
+fn query_single_row<T, P, F>(
+    conn: &Connection,
+    query: &str,
+    params: P,
+    map_fn: F,
+) -> Result<Option<T>, MmError<BlockHeaderStorageError>>
+where
+    P: IntoIterator,
+    P::Item: ToSql,
+    F: FnOnce(&Row<'_>) -> Result<T, SqlError>,
+{
+    db_common::sqlite::query_single_row(conn, query, params, map_fn).map_err(|e| {
+        MmError::new(BlockHeaderStorageError::QueryError {
+            query: query.to_string(),
+            reason: e.to_string(),
+        })
+    })
+}
+
+struct SqlBlockHeader {
+    block_height: String,
+    block_hex: String,
+}
+
+impl From<ElectrumBlockHeader> for SqlBlockHeader {
+    fn from(header: ElectrumBlockHeader) -> Self {
+        match header {
+            ElectrumBlockHeader::V12(h) => {
+                let block_hex = h.as_hex();
+                let block_height = h.block_height.to_string();
+                SqlBlockHeader {
+                    block_height,
+                    block_hex,
+                }
+            },
+            ElectrumBlockHeader::V14(h) => {
+                let block_hex = format!("{:02x}", h.hex);
+                let block_height = h.height.to_string();
+                SqlBlockHeader {
+                    block_height,
+                    block_hex,
+                }
+            },
+        }
+    }
+}
+async fn common_headers_insert(
+    for_coin: &str,
+    storage: SqliteBlockHeadersStorage,
+    headers: Vec<SqlBlockHeader>,
+) -> Result<(), MmError<BlockHeaderStorageError>> {
+    let for_coin = for_coin.to_owned();
+    let mut conn = storage.0.lock().unwrap();
+    let sql_transaction = conn
+        .transaction()
+        .map_err(|e| BlockHeaderStorageError::AddToStorageError {
+            ticker: for_coin.to_string(),
+            reason: e.to_string(),
+        })?;
+    for header in headers {
+        let block_cache_params = [&header.block_height, &header.block_hex];
+        sql_transaction
+            .execute(&insert_block_header_in_cache_sql(&for_coin)?, block_cache_params)
+            .map_err(|e| BlockHeaderStorageError::AddToStorageError {
+                ticker: for_coin.to_string(),
+                reason: e.to_string(),
+            })?;
+    }
+    sql_transaction
+        .commit()
+        .map_err(|e| BlockHeaderStorageError::AddToStorageError {
+            ticker: for_coin.to_string(),
+            reason: e.to_string(),
+        })?;
+    Ok(())
+}
+
+#[async_trait]
+impl BlockHeaderStorageOps for SqliteBlockHeadersStorage {
+    async fn init(&self, for_coin: &str) -> Result<(), MmError<BlockHeaderStorageError>> {
+        let selfi = self.clone();
+        let sql_cache = create_block_header_cache_table_sql(for_coin)?;
+        let ticker = for_coin.to_owned();
+        async_blocking(move || {
+            let conn = selfi.0.lock().unwrap();
+            conn.execute(&sql_cache, NO_PARAMS).map(|_| ()).map_err(|e| {
+                BlockHeaderStorageError::InitializationError {
+                    ticker,
+                    reason: e.to_string(),
+                }
+            })?;
+            Ok(())
+        })
+        .await
+    }
+
+    async fn is_initialized_for(&self, for_coin: &str) -> Result<bool, MmError<BlockHeaderStorageError>> {
+        let block_headers_cache_table = get_table_name_and_validate(for_coin)?;
+        let selfi = self.clone();
+        async_blocking(move || {
+            let conn = selfi.0.lock().unwrap();
+            let cache_initialized = query_single_row(
+                &conn,
+                CHECK_TABLE_EXISTS_SQL,
+                [block_headers_cache_table],
+                string_from_row,
+            )?;
+            Ok(cache_initialized.is_some())
+        })
+        .await
+    }
+
+    async fn add_electrum_block_headers_to_storage(
+        &self,
+        for_coin: &str,
+        headers: Vec<ElectrumBlockHeader>,
+    ) -> Result<(), MmError<BlockHeaderStorageError>> {
+        let headers_for_sql = headers.into_iter().map(Into::into).collect();
+        common_headers_insert(for_coin, self.clone(), headers_for_sql).await
+    }
+
+    async fn add_block_headers_to_storage(
+        &self,
+        for_coin: &str,
+        headers: HashMap<u64, BlockHeader>,
+    ) -> Result<(), MmError<BlockHeaderStorageError>> {
+        let headers_for_sql = headers
+            .into_iter()
+            .map(|(height, header)| SqlBlockHeader {
+                block_height: height.to_string(),
+                block_hex: hex::encode(header.raw()),
+            })
+            .collect();
+        common_headers_insert(for_coin, self.clone(), headers_for_sql).await
+    }
+
+    async fn get_block_header(
+        &self,
+        for_coin: &str,
+        height: u64,
+    ) -> Result<Option<BlockHeader>, MmError<BlockHeaderStorageError>> {
+        if let Some(header_raw) = self.get_block_header_raw(for_coin, height).await? {
+            let header_bytes = hex::decode(header_raw).map_err(|e| BlockHeaderStorageError::DecodeError {
+                ticker: for_coin.to_string(),
+                reason: e.to_string(),
+            })?;
+            let header: BlockHeader =
+                deserialize(header_bytes.as_slice()).map_err(|e| BlockHeaderStorageError::DecodeError {
+                    ticker: for_coin.to_string(),
+                    reason: e.to_string(),
+                })?;
+            return Ok(Some(header));
+        }
+        Ok(None)
+    }
+
+    async fn get_block_header_raw(
+        &self,
+        for_coin: &str,
+        height: u64,
+    ) -> Result<Option<String>, MmError<BlockHeaderStorageError>> {
+        let params = [height.to_string()];
+        let sql = get_block_header_by_height(for_coin)?;
+        let selfi = self.clone();
+
+        async_blocking(move || {
+            let conn = selfi.0.lock().unwrap();
+            query_single_row(&conn, &sql, params, string_from_row)
+        })
+        .await
+        .map_err(|e| {
+            MmError::new(BlockHeaderStorageError::GetFromStorageError {
+                ticker: for_coin.to_string(),
+                reason: e.into_inner().to_string(),
+            })
+        })
+    }
+}
+
+#[cfg(test)]
+impl SqliteBlockHeadersStorage {
+    pub fn in_memory() -> Self {
+        SqliteBlockHeadersStorage(Arc::new(Mutex::new(Connection::open_in_memory().unwrap())))
+    }
+
+    fn is_table_empty(&self, table_name: &str) -> bool {
+        validate_table_name(table_name).unwrap();
+        let sql = "SELECT COUNT(block_height) FROM ".to_owned() + table_name + ";";
+        let conn = self.0.lock().unwrap();
+        let rows_count: u32 = conn.query_row(&sql, NO_PARAMS, |row| row.get(0)).unwrap();
+        rows_count == 0
+    }
+}
+
+#[cfg(test)]
+mod sql_block_headers_storage_tests {
+    use super::*;
+    use crate::utxo::rpc_clients::ElectrumBlockHeaderV14;
+    use common::block_on;
+    use primitives::hash::H256;
+
+    #[test]
+    fn test_init_collection() {
+        let for_coin = "init_collection";
+        let storage = SqliteBlockHeadersStorage::in_memory();
+        let initialized = block_on(storage.is_initialized_for(for_coin)).unwrap();
+        assert!(!initialized);
+
+        block_on(storage.init(for_coin)).unwrap();
+        // repetitive init must not fail
+        block_on(storage.init(for_coin)).unwrap();
+
+        let initialized = block_on(storage.is_initialized_for(for_coin)).unwrap();
+        assert!(initialized);
+    }
+
+    #[test]
+    fn test_add_block_headers() {
+        let for_coin = "insert";
+        let storage = SqliteBlockHeadersStorage::in_memory();
+        let table = block_headers_cache_table(for_coin);
+        block_on(storage.init(for_coin)).unwrap();
+
+        let initialized = block_on(storage.is_initialized_for(for_coin)).unwrap();
+        assert!(initialized);
+
+        let block_header = ElectrumBlockHeaderV14 {
+            height: 520481,
+            hex: "0000002076d41d3e4b0bfd4c0d3b30aa69fdff3ed35d85829efd04000000000000000000b386498b583390959d9bac72346986e3015e83ac0b54bc7747a11a494ac35c94bb3ce65a53fb45177f7e311c".into(),
+        }.into();
+        let headers = vec![ElectrumBlockHeader::V14(block_header)];
+        block_on(storage.add_electrum_block_headers_to_storage(for_coin, headers)).unwrap();
+        assert!(!storage.is_table_empty(&table));
+    }
+
+    #[test]
+    fn test_get_block_header() {
+        let for_coin = "get";
+        let storage = SqliteBlockHeadersStorage::in_memory();
+        let table = block_headers_cache_table(for_coin);
+        block_on(storage.init(for_coin)).unwrap();
+
+        let initialized = block_on(storage.is_initialized_for(for_coin)).unwrap();
+        assert!(initialized);
+
+        let block_header = ElectrumBlockHeaderV14 {
+            height: 520481,
+            hex: "0000002076d41d3e4b0bfd4c0d3b30aa69fdff3ed35d85829efd04000000000000000000b386498b583390959d9bac72346986e3015e83ac0b54bc7747a11a494ac35c94bb3ce65a53fb45177f7e311c".into(),
+        }.into();
+        let headers = vec![ElectrumBlockHeader::V14(block_header)];
+        block_on(storage.add_electrum_block_headers_to_storage(for_coin, headers)).unwrap();
+        assert!(!storage.is_table_empty(&table));
+
+        let hex = block_on(storage.get_block_header_raw(for_coin, 520481))
+            .unwrap()
+            .unwrap();
+        assert_eq!(hex, "0000002076d41d3e4b0bfd4c0d3b30aa69fdff3ed35d85829efd04000000000000000000b386498b583390959d9bac72346986e3015e83ac0b54bc7747a11a494ac35c94bb3ce65a53fb45177f7e311c".to_string());
+
+        let block_header = block_on(storage.get_block_header(for_coin, 520481)).unwrap().unwrap();
+        assert_eq!(
+            block_header.hash(),
+            H256::from_reversed_str("0000000000000000002e31d0714a5ab23100945ff87ba2d856cd566a3c9344ec")
+        )
+    }
+}
diff --git a/mm2src/coins/utxo/utxo_tests.rs b/mm2src/coins/utxo/utxo_tests.rs
index 72101a374b..15e89dfc02 100644
--- a/mm2src/coins/utxo/utxo_tests.rs
+++ b/mm2src/coins/utxo/utxo_tests.rs
@@ -146,6 +146,7 @@ fn utxo_coin_fields_for_test(
         derivation_method,
         history_sync_state: Mutex::new(HistorySyncState::NotEnabled),
         tx_cache_directory: None,
+        block_headers_storage: None,
         recently_spent_outpoints: AsyncMutex::new(RecentlySpentOutPoints::new(my_script_pubkey)),
         tx_hash_algo: TxHashAlgo::DSHA256,
         check_utxo_maturity: false,
@@ -920,6 +921,22 @@ fn test_utxo_lock() {
     }
 }
 
+#[test]
+fn test_spv_proof() {
+    let client = electrum_client_for_test(RICK_ELECTRUM_ADDRS);
+    let coin = utxo_coin_for_test(
+        client.into(),
+        Some("spice describe gravity federal blast come thank unfair canal monkey style afraid"),
+        false,
+    );
+
+    // https://rick.explorer.dexstats.info/tx/78ea7839f6d1b0dafda2ba7e34c1d8218676a58bd1b33f03a5f76391f61b72b0
+    let tx_str = "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";
+    let tx: UtxoTx = tx_str.into();
+    let res = block_on(utxo_common::validate_spv_proof(coin.clone(), tx));
+    res.unwrap()
+}
+
 #[test]
 fn list_since_block_btc_serde() {
     // https://github.com/KomodoPlatform/atomicDEX-API/issues/563
diff --git a/mm2src/coins/utxo/utxo_withdraw.rs b/mm2src/coins/utxo/utxo_withdraw.rs
index 3bac44f458..a3fd8c6f20 100644
--- a/mm2src/coins/utxo/utxo_withdraw.rs
+++ b/mm2src/coins/utxo/utxo_withdraw.rs
@@ -104,20 +104,20 @@ where
 {
     fn coin(&self) -> &Coin;
 
-    fn from_address(&self) -> Address;
+    fn sender_address(&self) -> Address;
 
-    fn from_address_string(&self) -> String;
+    fn sender_address_string(&self) -> String;
 
     fn request(&self) -> &WithdrawRequest;
 
     fn signature_version(&self) -> SignatureVersion {
-        match self.from_address().addr_format {
+        match self.sender_address().addr_format {
             UtxoAddressFormat::Segwit => SignatureVersion::WitnessV0,
             _ => self.coin().as_ref().conf.signature_version,
         }
     }
 
-    fn prev_script(&self) -> Script { Builder::build_p2pkh(&self.from_address().hash) }
+    fn prev_script(&self) -> Script { Builder::build_p2pkh(&self.sender_address().hash) }
 
     fn on_generating_transaction(&self) -> Result<(), MmError<WithdrawError>>;
 
@@ -152,7 +152,7 @@ where
         let script_pubkey = output_script(&to, script_type).to_bytes();
 
         let _utxo_lock = UTXO_LOCK.lock().await;
-        let (unspents, _) = coin.list_unspent_ordered(&self.from_address()).await?;
+        let (unspents, _) = coin.list_unspent_ordered(&self.sender_address()).await?;
         let (value, fee_policy) = if req.max {
             (
                 unspents.iter().fold(0, |sum, unspent| sum + unspent.value),
@@ -165,7 +165,7 @@ where
         let outputs = vec![TransactionOutput { value, script_pubkey }];
 
         let mut tx_builder = UtxoTxBuilder::new(coin)
-            .with_from_address(self.from_address())
+            .with_from_address(self.sender_address())
             .add_available_inputs(unspents)
             .add_outputs(outputs)
             .with_fee_policy(fee_policy);
@@ -208,7 +208,7 @@ where
             _ => serialize(&signed).into(),
         };
         Ok(TransactionDetails {
-            from: vec![self.from_address_string()],
+            from: vec![self.sender_address_string()],
             to: vec![req.to.clone()],
             total_amount: big_decimal_from_sat(data.spent_by_me as i64, decimals),
             spent_by_me: big_decimal_from_sat(data.spent_by_me as i64, decimals),
@@ -248,9 +248,9 @@ where
 {
     fn coin(&self) -> &Coin { &self.coin }
 
-    fn from_address(&self) -> Address { self.from_address.clone() }
+    fn sender_address(&self) -> Address { self.from_address.clone() }
 
-    fn from_address_string(&self) -> String { self.from_address_string.clone() }
+    fn sender_address_string(&self) -> String { self.from_address_string.clone() }
 
     fn request(&self) -> &WithdrawRequest { &self.req }
 
@@ -436,9 +436,9 @@ where
 {
     fn coin(&self) -> &Coin { &self.coin }
 
-    fn from_address(&self) -> Address { self.my_address.clone() }
+    fn sender_address(&self) -> Address { self.my_address.clone() }
 
-    fn from_address_string(&self) -> String { self.my_address_string.clone() }
+    fn sender_address_string(&self) -> String { self.my_address_string.clone() }
 
     fn request(&self) -> &WithdrawRequest { &self.req }
 
diff --git a/mm2src/coins/utxo_signer/src/sign_common.rs b/mm2src/coins/utxo_signer/src/sign_common.rs
index 74a7c8906f..fff677f8fa 100644
--- a/mm2src/coins/utxo_signer/src/sign_common.rs
+++ b/mm2src/coins/utxo_signer/src/sign_common.rs
@@ -105,7 +105,7 @@ pub(crate) fn script_sig_with_pub(public_key: &PublicKey, fork_id: u32, signatur
     let builder = Builder::default();
     builder
         .push_data(&script_sig)
-        .push_data(&public_key.to_vec())
+        .push_data(public_key.to_vec().as_slice())
         .into_bytes()
 }
 
diff --git a/mm2src/common/Cargo.toml b/mm2src/common/Cargo.toml
index 2a42690578..d07aa57c21 100644
--- a/mm2src/common/Cargo.toml
+++ b/mm2src/common/Cargo.toml
@@ -42,7 +42,7 @@ log = "0.4.8"
 num-bigint = { version = "0.2", features = ["serde", "std"] }
 num-rational = { version = "0.2", features = ["serde", "bigint", "bigint-std"] }
 num-traits = "0.2"
-parking_lot = { version = "0.11", features = ["nightly"] }
+parking_lot = { version = "0.12.0", features = ["nightly"] }
 parking_lot_core = { version = "0.6", features = ["nightly"] }
 paste = "1.0"
 primitives = { path = "../mm2_bitcoin/primitives" }
diff --git a/mm2src/common/common.rs b/mm2src/common/common.rs
index 77f13fe168..fd03e2182a 100644
--- a/mm2src/common/common.rs
+++ b/mm2src/common/common.rs
@@ -1321,7 +1321,7 @@ pub fn round_to(bd: &BigDecimal, places: u8) -> String {
 
         if pos < dot {
             //println! ("{}, pos < dot, stopping at pos {}", bds, pos);
-            let mut integer: i64 = (&bds[0..=pos]).parse().unwrap();
+            let mut integer: i64 = (bds[0..=pos]).parse().unwrap();
             if prev_digit > 5 {
                 if bda[0] == b'-' {
                     integer = integer.checked_sub(1).unwrap()
diff --git a/mm2src/crypto/Cargo.toml b/mm2src/crypto/Cargo.toml
index 488fa0d4a9..eb3a682812 100644
--- a/mm2src/crypto/Cargo.toml
+++ b/mm2src/crypto/Cargo.toml
@@ -16,9 +16,9 @@ futures = "0.3"
 hex = "0.4.2"
 http = "0.2"
 hw_common = { path = "../hw_common" }
+parking_lot = { version = "0.12.0", features = ["nightly"] }
 keys = { path = "../mm2_bitcoin/keys" }
 num-traits = "0.1"
-parking_lot = { version = "0.11", features = ["nightly"] }
 primitives = { path = "../mm2_bitcoin/primitives" }
 rpc_task = { path = "../rpc_task" }
 secp256k1 = "0.20"
diff --git a/mm2src/db_common/src/sqlite.rs b/mm2src/db_common/src/sqlite.rs
index 7680996c31..4e11afb1ab 100644
--- a/mm2src/db_common/src/sqlite.rs
+++ b/mm2src/db_common/src/sqlite.rs
@@ -2,7 +2,7 @@ pub use rusqlite;
 pub use sql_builder;
 
 use log::debug;
-use rusqlite::{Connection, Error as SqlError, Result as SqlResult, ToSql};
+use rusqlite::{Connection, Error as SqlError, Result as SqlResult, Row, ToSql};
 use sql_builder::SqlBuilder;
 use std::sync::{Arc, Mutex, Weak};
 use uuid::Uuid;
@@ -10,6 +10,25 @@ use uuid::Uuid;
 pub type SqliteConnShared = Arc<Mutex<Connection>>;
 pub type SqliteConnWeak = Weak<Mutex<Connection>>;
 
+pub const CHECK_TABLE_EXISTS_SQL: &str = "SELECT name FROM sqlite_master WHERE type='table' AND name=?1;";
+
+pub fn string_from_row(row: &Row<'_>) -> Result<String, SqlError> { row.get(0) }
+
+pub fn query_single_row<T, P, F>(conn: &Connection, query: &str, params: P, map_fn: F) -> Result<Option<T>, SqlError>
+where
+    P: IntoIterator,
+    P::Item: ToSql,
+    F: FnOnce(&Row<'_>) -> Result<T, SqlError>,
+{
+    let maybe_result = conn.query_row(query, params, map_fn);
+    if let Err(SqlError::QueryReturnedNoRows) = maybe_result {
+        return Ok(None);
+    }
+
+    let result = maybe_result?;
+    Ok(Some(result))
+}
+
 pub fn validate_table_name(table_name: &str) -> SqlResult<()> {
     // As per https://stackoverflow.com/a/3247553, tables can't be the target of parameter substitution.
     // So we have to use a plain concatenation disallowing any characters in the table name that may lead to SQL injection.
diff --git a/mm2src/docker_tests.rs b/mm2src/docker_tests.rs
index 7984e3c0d3..968cb6b0e1 100644
--- a/mm2src/docker_tests.rs
+++ b/mm2src/docker_tests.rs
@@ -1432,7 +1432,7 @@ mod docker_tests {
             .unwrap();
         // TODO when buy call is made immediately swap might be not put into swap ctx yet so locked
         // amount returns 0
-        thread::sleep(Duration::from_secs(3));
+        thread::sleep(Duration::from_secs(6));
 
         let rc = block_on(mm_alice.rpc(json! ({
             "userpass": mm_alice.userpass,
@@ -1529,7 +1529,7 @@ mod docker_tests {
             .unwrap();
         // TODO when sell call is made immediately swap might be not put into swap ctx yet so locked
         // amount returns 0
-        thread::sleep(Duration::from_secs(3));
+        thread::sleep(Duration::from_secs(6));
 
         let rc = block_on(mm_alice.rpc(json! ({
             "userpass": mm_alice.userpass,
diff --git a/mm2src/docker_tests/qrc20_tests.rs b/mm2src/docker_tests/qrc20_tests.rs
index 85e5f10177..d45fa66de9 100644
--- a/mm2src/docker_tests/qrc20_tests.rs
+++ b/mm2src/docker_tests/qrc20_tests.rs
@@ -207,6 +207,7 @@ fn test_taker_spends_maker_payment() {
         secret_hash,
         amount: amount.clone(),
         swap_contract_address: taker_coin.swap_contract_address(),
+        confirmations,
     };
     taker_coin.validate_maker_payment(input).wait().unwrap();
 
@@ -297,6 +298,7 @@ fn test_maker_spends_taker_payment() {
         secret_hash: secret_hash.clone(),
         amount: amount.clone(),
         swap_contract_address: maker_coin.swap_contract_address(),
+        confirmations,
     };
     maker_coin.validate_taker_payment(input).wait().unwrap();
 
diff --git a/mm2src/gossipsub/src/behaviour.rs b/mm2src/gossipsub/src/behaviour.rs
index c702d907f9..b308c37ba8 100644
--- a/mm2src/gossipsub/src/behaviour.rs
+++ b/mm2src/gossipsub/src/behaviour.rs
@@ -849,7 +849,7 @@ impl Gossipsub {
                 .collect();
             let mut prunes: Vec<GossipsubControlAction> = to_prune
                 .remove(peer)
-                .unwrap_or_else(Vec::new)
+                .unwrap_or_default()
                 .iter()
                 .map(|topic_hash| GossipsubControlAction::Prune {
                     topic_hash: topic_hash.clone(),
@@ -1042,12 +1042,10 @@ impl Gossipsub {
         }
     }
 
-    pub fn get_mesh_peers(&self, topic: &TopicHash) -> Vec<PeerId> {
-        self.mesh.get(topic).cloned().unwrap_or_else(Vec::new)
-    }
+    pub fn get_mesh_peers(&self, topic: &TopicHash) -> Vec<PeerId> { self.mesh.get(topic).cloned().unwrap_or_default() }
 
     pub fn get_topic_peers(&self, topic: &TopicHash) -> Vec<PeerId> {
-        self.topic_peers.get(topic).cloned().unwrap_or_else(Vec::new)
+        self.topic_peers.get(topic).cloned().unwrap_or_default()
     }
 
     pub fn get_num_peers(&self) -> usize { self.peer_topics.len() }
diff --git a/mm2src/lp_ordermatch.rs b/mm2src/lp_ordermatch.rs
index bf3d7a347c..0bfc66fa09 100644
--- a/mm2src/lp_ordermatch.rs
+++ b/mm2src/lp_ordermatch.rs
@@ -3548,6 +3548,7 @@ pub struct TakerRequestForRpc<'a> {
     conf_settings: &'a Option<OrderConfirmationsSettings>,
 }
 
+#[allow(clippy::needless_borrow)]
 pub async fn lp_auto_buy(
     ctx: &MmArc,
     base_coin: &MmCoinEnum,
@@ -4067,6 +4068,7 @@ struct MakerMatchForRpc<'a> {
     last_updated: u64,
 }
 
+#[allow(clippy::needless_borrow)]
 impl<'a> From<&'a MakerMatch> for MakerMatchForRpc<'a> {
     fn from(maker_match: &'a MakerMatch) -> MakerMatchForRpc {
         MakerMatchForRpc {
@@ -4794,6 +4796,7 @@ struct TakerMatchForRpc<'a> {
     last_updated: u64,
 }
 
+#[allow(clippy::needless_borrow)]
 impl<'a> From<&'a TakerMatch> for TakerMatchForRpc<'a> {
     fn from(taker_match: &'a TakerMatch) -> TakerMatchForRpc {
         TakerMatchForRpc {
@@ -4816,6 +4819,7 @@ struct TakerOrderForRpc<'a> {
     rel_orderbook_ticker: &'a Option<String>,
 }
 
+#[allow(clippy::needless_borrow)]
 impl<'a> From<&'a TakerOrder> for TakerOrderForRpc<'a> {
     fn from(order: &'a TakerOrder) -> TakerOrderForRpc {
         TakerOrderForRpc {
diff --git a/mm2src/lp_swap/maker_swap.rs b/mm2src/lp_swap/maker_swap.rs
index ca84c482e5..72b9f8769e 100644
--- a/mm2src/lp_swap/maker_swap.rs
+++ b/mm2src/lp_swap/maker_swap.rs
@@ -767,12 +767,13 @@ impl MakerSwap {
     async fn validate_taker_payment(&self) -> Result<(Option<MakerSwapCommand>, Vec<MakerSwapEvent>), String> {
         let wait_duration = (self.r().data.lock_duration * 4) / 5;
         let wait_taker_payment = self.r().data.started_at + wait_duration;
+        let confirmations = self.r().data.taker_payment_confirmations;
 
         let wait_f = self
             .taker_coin
             .wait_for_confirmations(
                 &self.r().taker_payment.clone().unwrap().tx_hex,
-                self.r().data.taker_payment_confirmations,
+                confirmations,
                 self.r().data.taker_payment_requires_nota.unwrap_or(false),
                 wait_taker_payment,
                 WAIT_CONFIRM_INTERVAL,
@@ -797,6 +798,7 @@ impl MakerSwap {
             secret_hash: dhash160(&self.r().data.secret.0).to_vec(),
             amount: self.taker_amount.clone(),
             swap_contract_address: self.r().data.taker_coin_swap_contract_address.clone(),
+            confirmations,
         };
         let validated_f = self.taker_coin.validate_taker_payment(validate_input).compat();
 
diff --git a/mm2src/lp_swap/taker_swap.rs b/mm2src/lp_swap/taker_swap.rs
index 3e32e0a08c..57aa0e5b38 100644
--- a/mm2src/lp_swap/taker_swap.rs
+++ b/mm2src/lp_swap/taker_swap.rs
@@ -1097,9 +1097,10 @@ impl TakerSwap {
 
     async fn validate_maker_payment(&self) -> Result<(Option<TakerSwapCommand>, Vec<TakerSwapEvent>), String> {
         log!({ "Before wait confirm" });
+        let confirmations = self.r().data.maker_payment_confirmations;
         let f = self.maker_coin.wait_for_confirmations(
             &self.r().maker_payment.clone().unwrap().tx_hex,
-            self.r().data.maker_payment_confirmations,
+            confirmations,
             self.r().data.maker_payment_requires_nota.unwrap_or(false),
             self.r().data.maker_payment_wait,
             WAIT_CONFIRM_INTERVAL,
@@ -1121,6 +1122,7 @@ impl TakerSwap {
             secret_hash: self.r().secret_hash.0.to_vec(),
             amount: self.maker_amount.to_decimal(),
             swap_contract_address: self.r().data.maker_coin_swap_contract_address.clone(),
+            confirmations,
         };
         let validated = self.maker_coin.validate_maker_payment(validate_input).compat().await;
 
diff --git a/mm2src/mm2_bitcoin/chain/src/block_header.rs b/mm2src/mm2_bitcoin/chain/src/block_header.rs
index 95a713accc..962fca362f 100644
--- a/mm2src/mm2_bitcoin/chain/src/block_header.rs
+++ b/mm2src/mm2_bitcoin/chain/src/block_header.rs
@@ -2,6 +2,8 @@ use compact::Compact;
 use crypto::dhash256;
 use hash::H256;
 use hex::FromHex;
+use primitives::bytes::Bytes;
+use primitives::U256;
 use ser::{deserialize, serialize, Deserializable, Reader, Serializable, Stream};
 use std::io;
 use transaction::{deserialize_tx, TxType};
@@ -264,6 +266,13 @@ impl Deserializable for BlockHeader {
 
 impl BlockHeader {
     pub fn hash(&self) -> H256 { dhash256(&serialize(self)) }
+    pub fn raw(&self) -> Bytes { serialize(self) }
+    pub fn target(&self) -> Result<U256, U256> {
+        match self.bits {
+            BlockHeaderBits::Compact(compact) => compact.to_u256(),
+            BlockHeaderBits::U32(nb) => Ok(U256::from(nb)),
+        }
+    }
 }
 
 impl From<&'static str> for BlockHeader {
diff --git a/mm2src/mm2_bitcoin/chain/src/lib.rs b/mm2src/mm2_bitcoin/chain/src/lib.rs
index 8761e7c434..b3f474fd49 100644
--- a/mm2src/mm2_bitcoin/chain/src/lib.rs
+++ b/mm2src/mm2_bitcoin/chain/src/lib.rs
@@ -10,6 +10,8 @@ pub mod constants;
 mod block;
 mod block_header;
 mod merkle_root;
+mod raw_block;
+pub use raw_block::{RawBlockHeader, RawHeaderError};
 mod transaction;
 
 /// `IndexedBlock` extension
diff --git a/mm2src/mm2_bitcoin/chain/src/raw_block.rs b/mm2src/mm2_bitcoin/chain/src/raw_block.rs
new file mode 100644
index 0000000000..075d15ad6a
--- /dev/null
+++ b/mm2src/mm2_bitcoin/chain/src/raw_block.rs
@@ -0,0 +1,80 @@
+use crypto::dhash256;
+use primitives::bytes::Bytes;
+use primitives::hash::H256;
+use ser::serialize;
+use BlockHeader;
+
+pub const MIN_RAW_HEADER_SIZE: usize = 80_usize;
+
+/// Hex-encoded block
+#[derive(Default, PartialEq, Clone, Eq, Hash)]
+pub struct RawBlockHeader(Bytes);
+
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub enum RawHeaderError {
+    WrongLengthHeader { min_length: usize },
+}
+
+impl RawBlockHeader {
+    pub fn new(buf: Vec<u8>) -> Result<Self, RawHeaderError> {
+        if buf.len() < MIN_RAW_HEADER_SIZE {
+            return Err(RawHeaderError::WrongLengthHeader {
+                min_length: MIN_RAW_HEADER_SIZE,
+            });
+        }
+        let header = RawBlockHeader(buf.into());
+        Ok(header)
+    }
+
+    /// Calculate the LE header digest
+    pub fn digest(&self) -> H256 { dhash256(self.0.as_slice()) }
+
+    /// Extract the LE tx merkle root from the header
+    pub fn extract_merkle_root(&self) -> H256 {
+        let mut root = H256::default();
+        root.as_mut().copy_from_slice(&self.0.as_ref()[36..68]);
+        root
+    }
+
+    /// Extract the LE parent digest from the header
+    pub fn parent(&self) -> H256 {
+        let mut root = H256::default();
+        root.as_mut().copy_from_slice(&self.0.as_ref()[4..36]);
+        root
+    }
+}
+
+impl From<BlockHeader> for RawBlockHeader {
+    fn from(header: BlockHeader) -> Self {
+        let bytes = serialize(&header);
+        RawBlockHeader(bytes)
+    }
+}
+
+#[cfg(test)]
+mod raw_block_header_tests {
+    use hex::FromHex;
+    use primitives::hash::H256;
+    use raw_block::RawBlockHeader;
+
+    #[test]
+    fn test_raw_header() {
+        // block header of https://kmdexplorer.io/block/01ad31e22fea912a974c3e1eea11dc26348676528a586f77199ac3cfe29e271f
+        let header_hex = "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";
+        let header_bytes: Vec<u8> = header_hex.from_hex().unwrap();
+        let raw_header = RawBlockHeader::new(header_bytes).unwrap();
+        assert_eq!(
+            raw_header.digest(),
+            H256::from_reversed_str("01ad31e22fea912a974c3e1eea11dc26348676528a586f77199ac3cfe29e271f")
+        );
+        assert_eq!(
+            raw_header.extract_merkle_root(),
+            H256::from_reversed_str("63880212998e2aa48c87827aafee252c0d0c85a79e9b72ff724b63d2106602fa")
+        );
+
+        assert_eq!(
+            raw_header.parent(),
+            H256::from_reversed_str("023af943b167ababf8798537922e04d154160adb3509222d57d11db783724e8e")
+        );
+    }
+}
diff --git a/mm2src/mm2_bitcoin/spv_validation/Cargo.toml b/mm2src/mm2_bitcoin/spv_validation/Cargo.toml
new file mode 100644
index 0000000000..c8af6d79bb
--- /dev/null
+++ b/mm2src/mm2_bitcoin/spv_validation/Cargo.toml
@@ -0,0 +1,11 @@
+[package]
+name = "spv_validation"
+version = "0.1.0"
+authors = ["Roman Sztergbaum <rmscastle@gmail.com>"]
+
+[dependencies]
+bitcoin-spv = "5.0.0"
+chain = {path = "../chain"}
+primitives = { path = "../primitives" }
+serialization = { path = "../serialization" }
+rustc-hex = "2"
\ No newline at end of file
diff --git a/mm2src/mm2_bitcoin/spv_validation/src/helpers_validation.rs b/mm2src/mm2_bitcoin/spv_validation/src/helpers_validation.rs
new file mode 100644
index 0000000000..5665af9bcc
--- /dev/null
+++ b/mm2src/mm2_bitcoin/spv_validation/src/helpers_validation.rs
@@ -0,0 +1,173 @@
+use bitcoin_spv::btcspv::verify_hash256_merkle;
+use chain::{BlockHeader, RawBlockHeader};
+use primitives::hash::H256;
+use primitives::U256;
+use types::SPVError;
+
+/// Evaluates a Bitcoin merkle inclusion proof.
+/// Note that `index` is not a reliable indicator of location within a block.
+///
+/// # Arguments
+///
+/// * `txid` - The txid (LE)
+/// * `merkle_root` - The merkle root (as in the block header) (LE)
+/// * `intermediate_nodes` - The proof's intermediate nodes (digests between leaf and root) (LE)
+/// * `index` - The leaf's index in the tree (0-indexed)
+///
+/// # Notes
+/// Wrapper around `bitcoin_spv::validatespv::prove`
+pub fn merkle_prove(txid: H256, merkle_root: H256, intermediate_nodes: Vec<H256>, index: u64) -> Result<(), SPVError> {
+    if txid == merkle_root && index == 0 && intermediate_nodes.is_empty() {
+        return Ok(());
+    }
+    let vec: Vec<u8> = intermediate_nodes.into_iter().flat_map(|node| node.take()).collect();
+    let nodes = bitcoin_spv::types::MerkleArray::new(vec.as_slice())?;
+    if !verify_hash256_merkle(txid.take().into(), merkle_root.take().into(), &nodes, index) {
+        return Err(SPVError::BadMerkleProof);
+    }
+    Ok(())
+}
+
+fn validate_header_prev_hash(actual: &H256, to_compare_with: &H256) -> bool { actual == to_compare_with }
+
+pub fn validate_header_work(digest: H256, target: &U256) -> bool {
+    let empty = H256::default();
+
+    if digest == empty {
+        return false;
+    }
+
+    U256::from_little_endian(digest.as_slice()) < *target
+}
+
+/// Checks validity of header chain.
+/// Compares the hash of each header to the prevHash in the next header.
+///
+/// # Arguments
+///
+/// * `headers` - Raw byte array of header chain
+/// * `difficulty_check`: Rather the difficulty need to check or not, usefull for chain like Qtum (Pos)
+/// or KMD/SmartChain (Difficulty change NN)
+/// * `constant_difficulty`: If we do not expect difficulty change (BTC difficulty change every 2016 blocks)
+/// use this variable to false when you do not have a chance to use a checkpoint
+///
+/// # Errors
+///
+/// * Errors if header chain is invalid, insufficient work, unexpected difficulty change or unable to get a target
+///
+/// # Notes
+/// Wrapper inspired by `bitcoin_spv::validatespv::validate_header_chain`
+pub fn validate_headers(
+    headers: Vec<BlockHeader>,
+    difficulty_check: bool,
+    constant_difficulty: bool,
+) -> Result<(), SPVError> {
+    let mut previous_hash = H256::default();
+    let mut target = U256::default();
+    for (i, header) in headers.into_iter().enumerate() {
+        let raw_header = RawBlockHeader::from(header.clone());
+        if i == 0 {
+            target = match header.target() {
+                Ok(target) => target,
+                Err(_) => return Err(SPVError::UnableToGetTarget),
+            };
+        }
+        let cur_target = match header.target() {
+            Ok(target) => target,
+            Err(_) => return Err(SPVError::UnableToGetTarget),
+        };
+        if (!constant_difficulty && difficulty_check) && cur_target != target {
+            return Err(SPVError::UnexpectedDifficultyChange);
+        }
+        if i != 0 && !validate_header_prev_hash(&raw_header.parent(), &previous_hash) {
+            return Err(SPVError::InvalidChain);
+        }
+        if difficulty_check && !validate_header_work(raw_header.digest(), &target) {
+            return Err(SPVError::InsufficientWork);
+        }
+        previous_hash = raw_header.digest();
+    }
+    Ok(())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_merkle_prove_inclusion() {
+        // https://rick.explorer.dexstats.info/tx/7e9797a05abafbc1542449766ef9a41838ebbf6d24cd3223d361aa07c51981df
+        // merkle intermediate nodes 2 element
+        let tx_id: H256 = H256::from_reversed_str("7e9797a05abafbc1542449766ef9a41838ebbf6d24cd3223d361aa07c51981df");
+        let merkle_pos = 1;
+        let merkle_root: H256 =
+            H256::from_reversed_str("41f138275d13690e3c5d735e2f88eb6f1aaade1207eb09fa27a65b40711f3ae0").into();
+        let merkle_nodes: Vec<H256> = vec![
+            H256::from_reversed_str("73dfb53e6f49854b09d98500d4899d5c4e703c4fa3a2ddadc2cd7f12b72d4182"),
+            H256::from_reversed_str("4274d707b2308d39a04f2940024d382fa80d994152a50d4258f5a7feead2a563"),
+        ];
+        let result = merkle_prove(tx_id, merkle_root, merkle_nodes, merkle_pos);
+        result.unwrap()
+    }
+
+    #[test]
+    fn test_merkle_prove_inclusion_single_element() {
+        // https://www.blockchain.com/btc/tx/c06fbab289f723c6261d3030ddb6be121f7d2508d77862bb1e484f5cd7f92b25
+        // merkle intermediate nodes single element
+        let tx_id: H256 = H256::from_reversed_str("c06fbab289f723c6261d3030ddb6be121f7d2508d77862bb1e484f5cd7f92b25");
+        let merkle_pos = 0;
+        let merkle_root: H256 =
+            H256::from_reversed_str("8fb300e3fdb6f30a4c67233b997f99fdd518b968b9a3fd65857bfe78b2600719").into();
+        let merkle_nodes: Vec<H256> = vec![H256::from_reversed_str(
+            "5a4ebf66822b0b2d56bd9dc64ece0bc38ee7844a23ff1d7320a88c5fdb2ad3e2",
+        )];
+        let result = merkle_prove(tx_id, merkle_root, merkle_nodes, merkle_pos);
+        result.unwrap()
+    }
+
+    #[test]
+    fn test_merkle_prove_inclusion_complex() {
+        // https://www.blockchain.com/btc/tx/b36bced99cc459506ad2b3af6990920b12f6dc84f9c7ed0dd2c3703f94a4b692
+        // merkle intermediate nodes complex merkle proof inclusion
+        let tx_id: H256 = H256::from_reversed_str("b36bced99cc459506ad2b3af6990920b12f6dc84f9c7ed0dd2c3703f94a4b692");
+        let merkle_pos = 680;
+        let merkle_root: H256 =
+            H256::from_reversed_str("def7a26d91789069dad448cb4b68658b7ba419f9fbd28dce7fe32ed0010e55df").into();
+        let merkle_nodes: Vec<H256> = vec![
+            H256::from_reversed_str("39141331f2b7133e72913460384927b421ffdef3e24b88521e7ac54d30019409"),
+            H256::from_reversed_str("39aeb77571ee0b0cf9feb7e121938b862f3994ff1254b34559378f6f2ed8b1fb"),
+            H256::from_reversed_str("5815f83f4eb2423c708127ea1f47feeabcf005d4aed18701d9692925f152d0b4"),
+            H256::from_reversed_str("efbb90aae6875af1b05a17e53fabe79ca1655329d6e107269a190739bf9d9038"),
+            H256::from_reversed_str("20eb7431ae5a185e89bd2ad89956fc660392ee9d231df58600ac675734013e82"),
+            H256::from_reversed_str("1f1dd980e6196ec4de9037941076a6030debe466dfc177e54447171b64ea99e5"),
+            H256::from_reversed_str("bbc4264359bec656298e31443034fc3ff9877752b765b9665b4da1eb8a32d1ff"),
+            H256::from_reversed_str("71788bf5224f228f390243a2664d41d96bae97ae1e4cfbc39095448e4cd1addd"),
+            H256::from_reversed_str("1b24a907c86e59eb698afeb4303c00fe3ecf8425270134ed3d0e62c6991621f2"),
+            H256::from_reversed_str("7776b46bb148c573d5eabe1436a428f3dae484557fea6efef1da901009ca5f8f"),
+            H256::from_reversed_str("623a90d6122a233b265aab497b13bb64b5d354d2e2112c3f554e51bfa4e6bbd3"),
+            H256::from_reversed_str("3104295d99163e16405b80321238a97d02e2448bb634017e2e027281cc4af9e8"),
+        ];
+        let result = merkle_prove(tx_id, merkle_root, merkle_nodes, merkle_pos);
+        result.unwrap()
+    }
+
+    #[test]
+    fn test_block_headers_no_difficulty_check() {
+        // morty: 1330480, 1330481, 1330482
+        let headers: Vec<BlockHeader> = vec![
+            "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".into(),
+            "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".into(),
+            "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".into()
+        ];
+        validate_headers(headers, false, false).unwrap()
+    }
+
+    #[test]
+    fn test_block_headers_difficulty_check() {
+        // BTC: 724609, 724610, 724611
+        let headers: Vec<BlockHeader> = vec!["00200020eab6fa183da8f9e4c761b31a67a76fa6a7658eb84c760200000000000000000063cd9585d434ec0db25894ec4b1f03735f10e31709c4395ea67c50c8378f134b972f166278100a17bfd87203".into(), 
+                                             "0000402045c698413fbe8b5bf10635658d2a1cec72062798e51200000000000000000000869617420a4c95b1d3d6d012419d2b6c199cff9b68dd9a790892a4da8466fb056033166278100a1743ac4d5b".into(), 
+                                             "0400e02019d733c1fd76a1fa5950de7bee9d80f107276b93a67204000000000000000000a0d1dee718f5f732c041800e9aa2c25e92be3f6de28278545388db8a6ae27df64c37166278100a170a970c19".into()];
+        validate_headers(headers, true, true).unwrap()
+    }
+}
diff --git a/mm2src/mm2_bitcoin/spv_validation/src/lib.rs b/mm2src/mm2_bitcoin/spv_validation/src/lib.rs
new file mode 100644
index 0000000000..c0d52eb202
--- /dev/null
+++ b/mm2src/mm2_bitcoin/spv_validation/src/lib.rs
@@ -0,0 +1,14 @@
+extern crate bitcoin_spv;
+extern crate chain;
+extern crate primitives;
+extern crate rustc_hex as hex;
+extern crate serialization;
+
+/// `types` exposes simple types for on-chain evaluation of SPV proofs
+pub mod types;
+
+/// `helpers_validation` Override function modules from bitcoin_spv and adapt for our mm2_bitcoin library
+pub mod helpers_validation;
+
+/// `spv_proof` Contains spv proof validation logic and data structure
+pub mod spv_proof;
diff --git a/mm2src/mm2_bitcoin/spv_validation/src/spv_proof.rs b/mm2src/mm2_bitcoin/spv_validation/src/spv_proof.rs
new file mode 100644
index 0000000000..38e8461c88
--- /dev/null
+++ b/mm2src/mm2_bitcoin/spv_validation/src/spv_proof.rs
@@ -0,0 +1,93 @@
+use bitcoin_spv::btcspv::{validate_vin, validate_vout};
+use chain::BlockHeader;
+use chain::RawBlockHeader;
+use helpers_validation::merkle_prove;
+use primitives::hash::H256;
+use types::SPVError;
+
+#[derive(PartialEq, Clone)]
+pub struct SPVProof {
+    /// The tx id
+    pub tx_id: H256,
+    /// The vin serialized
+    pub vin: Vec<u8>,
+    /// The vout serialized
+    pub vout: Vec<u8>,
+    /// The transaction index in the merkle tree
+    pub index: u64,
+    /// The confirming UTXO header
+    pub confirming_header: BlockHeader,
+    /// The Raw confirming UTXO Header
+    pub raw_header: RawBlockHeader,
+    /// The intermediate nodes (digests between leaf and root)
+    pub intermediate_nodes: Vec<H256>,
+}
+
+/// Checks validity of an entire SPV Proof
+///
+/// # Arguments
+///
+/// * `self` - The SPV Proof
+///
+/// # Errors
+///
+/// * Errors if any of the SPV Proof elements are invalid.
+///
+/// # Notes
+/// Re-write with our own types based on `bitcoin_spv::std_types::SPVProof::validate`
+impl SPVProof {
+    pub fn validate_block_header(&self) -> Result<(), SPVError> {
+        if self.confirming_header.hash() != self.raw_header.digest() {
+            return Err(SPVError::WrongDigest);
+        }
+        if self.confirming_header.merkle_root_hash != self.raw_header.extract_merkle_root() {
+            return Err(SPVError::WrongMerkleRoot);
+        }
+        if self.confirming_header.previous_header_hash != self.raw_header.parent() {
+            return Err(SPVError::WrongPrevHash);
+        }
+        Ok(())
+    }
+
+    pub fn validate(&self) -> Result<(), SPVError> {
+        if !validate_vin(self.vin.as_slice()) {
+            return Err(SPVError::InvalidVin);
+        }
+        if !validate_vout(self.vout.as_slice()) {
+            return Err(SPVError::InvalidVout);
+        }
+        self.validate_block_header()?;
+        merkle_prove(
+            self.tx_id,
+            self.confirming_header.merkle_root_hash,
+            self.intermediate_nodes.clone(),
+            self.index,
+        )
+    }
+}
+
+#[cfg(test)]
+mod spv_proof_tests {
+    use chain::BlockHeader;
+    use chain::RawBlockHeader;
+    use hex::FromHex;
+    use serialization::deserialize;
+    use spv_proof::SPVProof;
+
+    #[test]
+    fn test_block_header() {
+        let header_hex = "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";
+        let header_bytes: Vec<u8> = header_hex.from_hex().unwrap();
+        let header: BlockHeader = deserialize(header_bytes.as_slice()).unwrap();
+        let spv_proof = SPVProof {
+            tx_id: Default::default(),
+            vin: vec![],
+            vout: vec![],
+            index: 0,
+            confirming_header: header,
+            raw_header: RawBlockHeader::new(header_bytes).unwrap(),
+            intermediate_nodes: vec![],
+        };
+        spv_proof.validate_block_header().unwrap()
+    }
+}
diff --git a/mm2src/mm2_bitcoin/spv_validation/src/types.rs b/mm2src/mm2_bitcoin/spv_validation/src/types.rs
new file mode 100644
index 0000000000..4840f7556b
--- /dev/null
+++ b/mm2src/mm2_bitcoin/spv_validation/src/types.rs
@@ -0,0 +1,97 @@
+use chain::RawHeaderError;
+
+#[derive(Debug, PartialEq, Eq, Clone)]
+pub enum SPVError {
+    /// Overran a checked read on a slice
+    ReadOverrun,
+    /// Attempted to parse a CompactInt without enough bytes
+    BadCompactInt,
+    /// Called `extract_op_return_data` on an output without an op_return.
+    MalformattedOpReturnOutput,
+    /// `extract_hash` identified a SH output prefix without a SH postfix.
+    MalformattedP2SHOutput,
+    /// `extract_hash` identified a PKH output prefix without a PKH postfix.
+    MalformattedP2PKHOutput,
+    /// `extract_hash` identified a Witness output with a bad length tag.
+    MalformattedWitnessOutput,
+    /// `extract_hash` could not identify the output type.
+    MalformattedOutput,
+    /// Unable to get target from block header
+    UnableToGetTarget,
+    /// Unable to get block header from network or storage
+    UnableToGetHeader,
+    /// Unable to deserialize raw block header from electrum to concrete type
+    MalformattedHeader,
+    /// Header not exactly 80 bytes.
+    WrongLengthHeader,
+    /// Header chain changed difficulties unexpectedly
+    UnexpectedDifficultyChange,
+    /// Header does not meet its own difficulty target.
+    InsufficientWork,
+    /// Header in chain does not correctly reference parent header.
+    InvalidChain,
+    /// When validating a `BitcoinHeader`, the `hash` field is not the digest
+    /// of the raw header.
+    WrongDigest,
+    /// When validating a `BitcoinHeader`, the `merkle_root` field does not
+    /// match the root found in the raw header.
+    WrongMerkleRoot,
+    /// When validating a `BitcoinHeader`, the `prevhash` field does not
+    /// match the parent hash found in the raw header.
+    WrongPrevHash,
+    /// A `vin` (transaction input vector) is malformatted.
+    InvalidVin,
+    /// A `vout` (transaction output vector) is malformatted or empty.
+    InvalidVout,
+    /// When validating an `SPVProof`, the `tx_id` field is not the digest
+    /// of the `version`, `vin`, `vout`, and `locktime`.
+    WrongTxID,
+    /// When validating an `SPVProof`, the `intermediate_nodes` is not a valid
+    /// merkle proof connecting the `tx_id_le` to the `confirming_header`.
+    BadMerkleProof,
+    /// Unable to get merkle tree from network or storage
+    UnableToGetMerkle,
+    /// TxOut's reported length does not match passed-in byte slice's length
+    OutputLengthMismatch,
+    /// Unable to retrieve block height / block height is zero.
+    InvalidHeight,
+    /// Block Header Not Verified / Verification failed
+    BlockHeaderNotVerified,
+    /// Any other error
+    UnknownError,
+}
+
+impl From<bitcoin_spv::types::SPVError> for SPVError {
+    fn from(e: bitcoin_spv::types::SPVError) -> Self {
+        match e {
+            bitcoin_spv::types::SPVError::ReadOverrun => SPVError::ReadOverrun,
+            bitcoin_spv::types::SPVError::BadCompactInt => SPVError::BadCompactInt,
+            bitcoin_spv::types::SPVError::MalformattedOpReturnOutput => SPVError::MalformattedOpReturnOutput,
+            bitcoin_spv::types::SPVError::MalformattedP2SHOutput => SPVError::MalformattedP2SHOutput,
+            bitcoin_spv::types::SPVError::MalformattedP2PKHOutput => SPVError::MalformattedP2PKHOutput,
+            bitcoin_spv::types::SPVError::MalformattedWitnessOutput => SPVError::MalformattedWitnessOutput,
+            bitcoin_spv::types::SPVError::MalformattedOutput => SPVError::MalformattedOutput,
+            bitcoin_spv::types::SPVError::WrongLengthHeader => SPVError::WrongLengthHeader,
+            bitcoin_spv::types::SPVError::UnexpectedDifficultyChange => SPVError::UnexpectedDifficultyChange,
+            bitcoin_spv::types::SPVError::InsufficientWork => SPVError::InsufficientWork,
+            bitcoin_spv::types::SPVError::InvalidChain => SPVError::InvalidChain,
+            bitcoin_spv::types::SPVError::WrongDigest => SPVError::WrongDigest,
+            bitcoin_spv::types::SPVError::WrongMerkleRoot => SPVError::WrongMerkleRoot,
+            bitcoin_spv::types::SPVError::WrongPrevHash => SPVError::WrongPrevHash,
+            bitcoin_spv::types::SPVError::InvalidVin => SPVError::InvalidVin,
+            bitcoin_spv::types::SPVError::InvalidVout => SPVError::InvalidVout,
+            bitcoin_spv::types::SPVError::WrongTxID => SPVError::WrongTxID,
+            bitcoin_spv::types::SPVError::BadMerkleProof => SPVError::BadMerkleProof,
+            bitcoin_spv::types::SPVError::OutputLengthMismatch => SPVError::OutputLengthMismatch,
+            bitcoin_spv::types::SPVError::UnknownError => SPVError::UnknownError,
+        }
+    }
+}
+
+impl From<RawHeaderError> for SPVError {
+    fn from(e: RawHeaderError) -> Self {
+        match e {
+            RawHeaderError::WrongLengthHeader { .. } => SPVError::WrongLengthHeader,
+        }
+    }
+}
diff --git a/rust-toolchain.toml b/rust-toolchain.toml
index 4566e0b2cb..6c54b7e3e3 100644
--- a/rust-toolchain.toml
+++ b/rust-toolchain.toml
@@ -1,3 +1,3 @@
 [toolchain]
-channel = "nightly-2021-12-16"
+channel = "nightly-2022-02-01"
 components = ["rustfmt"]