improve readme

README.md

@@ -4,11 +4,17 @@
 
 [![demo](https://github.com/user-attachments/assets/44c87053-8aa1-462f-929f-2a355328387c)](https://github.com/user-attachments/assets/e2da4817-237a-4e90-9c5e-b6f24e4ad57c)
 
-> **note:** currently Linux has the best support, Windows is supported partially, see [support matrix](https://docs.rs/relib/latest/relib/docs/index.html#feature-support-matrix).
+## Platforms supported
+
+currently Linux has the best support, Windows is supported partially, macOS is not supported (not tested), see [support matrix](https://docs.rs/relib/latest/relib/docs/index.html#feature-support-matrix).
 
 ## Overview
 
-`relib` is an attempt to make *native* Rust more usable to reload code on the fly, without closing down application, mainly for development (live/hot reload), although `relib` also provides [imports/exports](https://docs.rs/relib/latest/relib/docs/index.html#communication-between-host-and-module) mechanism, which can be used in production.
+`relib` tries to be a safe (as much as possible) runtime of native, almost normal Rust programs. Programs that can be safely unloaded (without memory leaks and crashes) without closing the whole OS process.
+
+Since it's not possible to make this completely safe: memory leaks, UB can still happen (for example, due to some unsafe call to C library), you should only use unloading for development (see [live reload](https://github.com/xxshady/relib/tree/main/examples/README.md#live-reload) example). `relib` also provides [imports/exports](https://docs.rs/relib/latest/relib/docs/index.html#communication-between-host-and-module) mechanism which can also be used in production.
+
+See [feature support matrix](https://docs.rs/relib/latest/relib/docs/index.html#feature-support-matrix) for what `relib` offers to improve unloading of dynamic libraries in Rust. And for what not, check out [limitations](#limitations).
 
 ## Examples
 
@@ -20,6 +26,18 @@ See [`docs`](https://docs.rs/relib/latest/relib/docs/index.html) of `relib` crat
 
 ## Limitations
 
+### Imports/exports runtime validation
+
+*Currently*, `relib` doesn't check in runtime that function signatures (arguments, return types) specified in imports and exports traits (`main` and [`before_unload`](https://docs.rs/relib/latest/relib/docs/index.html#before_unload) as well) are exactly the same for host and module.
+
+### ABI stability
+
+> [Why would I want a stable ABI? And what even is an ABI?](https://docs.rs/stabby/latest/stabby/#why-would-i-want-a-stable-abi-and-what-even-is-an-abi)
+
+To ensure at least something about ABI `relib` **checks and requires that host and module are compiled with the same rustc and `relib` version**.
+
+For ABI stable types, you can use abi_stable or stabby crate for it, see `abi_stable` usage [example](https://github.com/xxshady/relib/tree/main/examples/README.md#usage-with-abi_stable-crate).
+
 ### File descriptors and network sockets
 
 *Currently*, `relib` knows nothing about file descriptors or network sockets (unlike [background threads](https://docs.rs/relib/latest/relib/docs/index.html#background-threads-check)) so, for example, if your program stores them in static items and does not properly close them they will leak after unloading.