diff --git a/odoc-parser.opam b/odoc-parser.opam
index 1458575222..efff0d8f1b 100644
--- a/odoc-parser.opam
+++ b/odoc-parser.opam
@@ -17,7 +17,6 @@ depends: [
   "dune" {>= "3.7"}
   "ocaml" {>= "4.08.0" & < "5.4"}
   "astring"
-  "result"
   "camlp-streams"
   "ppx_expect" {with-test}
   "sexplib0" {with-test}
diff --git a/odoc.opam b/odoc.opam
index 5169c7dea1..f4e5d5ab1e 100644
--- a/odoc.opam
+++ b/odoc.opam
@@ -47,7 +47,6 @@ depends: [
   "dune" {>= "3.7.0"}
   "fpath"
   "ocaml" {>= "4.08.0" & < "5.4"}
-  "result"
   "tyxml" {>= "4.4.0"}
   "fmt"
   "crunch" {>= "1.4.1"}
diff --git a/src/document/codefmt.ml b/src/document/codefmt.ml
index 729a2d1423..a6fc05f56c 100644
--- a/src/document/codefmt.ml
+++ b/src/document/codefmt.ml
@@ -42,6 +42,27 @@ module State = struct
       flush state)
 end
 
+let rec compute_length_source (t : Types.Source.t) : int =
+  let f (acc : int) = function
+    | Types.Source.Elt t -> acc + compute_length_inline t
+    | Types.Source.Tag (_, t) -> acc + compute_length_source t
+  in
+  List.fold_left f 0 t
+
+and compute_length_inline (t : Types.Inline.t) : int =
+  let f (acc : int) { Types.Inline.desc; _ } =
+    match desc with
+    | Text s -> acc + String.length s
+    | Entity _e -> acc + 1
+    | Linebreak -> 0 (* TODO *)
+    | Styled (_, t) | Link { content = t; _ } -> acc + compute_length_inline t
+    | Source s -> acc + compute_length_source s
+    | Math _ -> assert false
+    | Raw_markup _ -> assert false
+    (* TODO *)
+  in
+  List.fold_left f 0 t
+
 (** Modern implementation using semantic tags, Only for 4.08+ *)
 
 (*
@@ -79,7 +100,7 @@ module Tag = struct
 
   let elt ppf elt =
     Format.pp_open_stag ppf (Elt elt);
-    Format.pp_print_as ppf (Utils.compute_length_inline elt) "";
+    Format.pp_print_as ppf (compute_length_inline elt) "";
     Format.pp_close_stag ppf ()
 
   let ignore ppf txt =
@@ -140,7 +161,7 @@ module Tag = struct
 
   let elt ppf (elt : Inline.t) =
     Format.fprintf ppf "@{<tag:%s>%t@}" (Marshal.to_string elt []) (fun fmt ->
-        Format.pp_print_as fmt (Utils.compute_length_inline elt) "")
+        Format.pp_print_as fmt (compute_length_inline elt) "")
 
   let ignore ppf txt = Format.fprintf ppf "@{<ignore-tag>%t@}" txt
 end
diff --git a/src/document/comment.ml b/src/document/comment.ml
index 7f0375b823..145b141c41 100644
--- a/src/document/comment.ml
+++ b/src/document/comment.ml
@@ -14,6 +14,7 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  *)
 
+open Odoc_utils
 open Types
 module Comment = Odoc_model.Comment
 open Odoc_model.Names
@@ -67,7 +68,7 @@ module Reference = struct
       | `TAbsolutePath -> "/"
       | `TCurrentPackage -> "//"
     in
-    tag ^ String.concat "/" cs
+    tag ^ String.concat ~sep:"/" cs
 
   let rec render_unresolved : Reference.t -> string =
     let open Reference in
@@ -412,11 +413,11 @@ let synopsis ~decl_doc ~expansion_doc =
   match Comment.synopsis docs with Some p -> [ paragraph p ] | None -> []
 
 let standalone docs =
-  Utils.flatmap ~f:item_element
+  List.concat_map item_element
   @@ List.map (fun x -> x.Odoc_model.Location_.value) docs
 
 let to_ir (docs : Comment.elements) =
-  Utils.flatmap ~f:block_element
+  List.concat_map block_element
   @@ List.map (fun x -> x.Odoc_model.Location_.value) docs
 
 let has_doc docs = docs <> []
diff --git a/src/document/doctree.ml b/src/document/doctree.ml
index d48ff41bb6..02eb782266 100644
--- a/src/document/doctree.ml
+++ b/src/document/doctree.ml
@@ -1,3 +1,4 @@
+open Odoc_utils
 open Types
 
 module Take = struct
@@ -97,19 +98,23 @@ module Subpages : sig
   val compute : Page.t -> Subpage.t list
 end = struct
   let rec walk_documentedsrc (l : DocumentedSrc.t) =
-    Utils.flatmap l ~f:(function
-      | DocumentedSrc.Code _ -> []
-      | Documented _ -> []
-      | Nested { code; _ } -> walk_documentedsrc code
-      | Subpage p -> [ p ]
-      | Alternative (Expansion r) -> walk_documentedsrc r.expansion)
+    List.concat_map
+      (function
+        | DocumentedSrc.Code _ -> []
+        | Documented _ -> []
+        | Nested { code; _ } -> walk_documentedsrc code
+        | Subpage p -> [ p ]
+        | Alternative (Expansion r) -> walk_documentedsrc r.expansion)
+      l
 
   let rec walk_items (l : Item.t list) =
-    Utils.flatmap l ~f:(function
-      | Item.Text _ -> []
-      | Heading _ -> []
-      | Declaration { content; _ } -> walk_documentedsrc content
-      | Include i -> walk_items i.content.content)
+    List.concat_map
+      (function
+        | Item.Text _ -> []
+        | Heading _ -> []
+        | Declaration { content; _ } -> walk_documentedsrc content
+        | Include i -> walk_items i.content.content)
+      l
 
   let compute (p : Page.t) = walk_items (p.preamble @ p.items)
 end
diff --git a/src/document/generator.ml b/src/document/generator.ml
index 14f8c662f1..70c5d82be7 100644
--- a/src/document/generator.ml
+++ b/src/document/generator.ml
@@ -14,6 +14,7 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  *)
 
+open Odoc_utils
 open Odoc_model.Names
 module Location = Odoc_model.Location_
 module Paths = Odoc_model.Paths
@@ -76,7 +77,7 @@ let mk_heading ?(level = 1) ?label text =
     rest is inserted into [items]. *)
 let prepare_preamble comment items =
   let preamble, first_comment =
-    Utils.split_at
+    List.split_at
       ~f:(function
         | { Odoc_model.Location_.value = `Heading _; _ } -> true | _ -> false)
       comment
@@ -213,7 +214,7 @@ module Make (Syntax : SYNTAX) = struct
         let in_bound x = min (max x 0) (String.length src) in
         let a = in_bound a and b = in_bound b in
         let a, b = (min a b, max a b) in
-        String.sub src a (b - a)
+        String.with_range src ~first:a ~len:(b - a)
       in
       let plain_code = function
         | "" -> []
@@ -358,7 +359,7 @@ module Make (Syntax : SYNTAX) = struct
            | Open -> O.txt "[> " ++ elements ++ O.txt " ]"
            | Closed [] -> O.txt "[< " ++ elements ++ O.txt " ]"
            | Closed lst ->
-               let constrs = String.concat " " lst in
+               let constrs = String.concat ~sep:" " lst in
                O.txt "[< " ++ elements ++ O.txt (" " ^ constrs ^ " ]"))
 
     and te_object (t : Odoc_model.Lang.TypeExpr.Object.t) =
@@ -461,7 +462,7 @@ module Make (Syntax : SYNTAX) = struct
           format_type_path ~delim:`brackets args
             (Link.from_path (path :> Paths.Path.t))
       | Poly (polyvars, t) ->
-          O.txt ("'" ^ String.concat " '" polyvars ^ ". ") ++ type_expr t
+          O.txt ("'" ^ String.concat ~sep:" '" polyvars ^ ". ") ++ type_expr t
       | Package pkg ->
           enclose ~l:"(" ~r:")"
             (O.keyword "module" ++ O.txt " "
@@ -747,7 +748,7 @@ module Make (Syntax : SYNTAX) = struct
         | Closed [] ->
             (O.documentedSrc (O.txt "[< "), O.documentedSrc (O.txt " ]"))
         | Closed lst ->
-            let constrs = String.concat " " lst in
+            let constrs = String.concat ~sep:" " lst in
             ( O.documentedSrc (O.txt "[< "),
               O.documentedSrc (O.txt (" " ^ constrs ^ " ]")) )
       in
@@ -773,14 +774,14 @@ module Make (Syntax : SYNTAX) = struct
           | Some Odoc_model.Lang.TypeDecl.Neg -> "-" :: desc
         in
         let final = if injectivity then "!" :: var_desc else var_desc in
-        String.concat "" final
+        String.concat ~sep:"" final
       in
       O.txt
         (match params with
         | [] -> ""
         | [ x ] -> format_param x |> Syntax.Type.handle_format_params
         | lst -> (
-            let params = String.concat ", " (List.map format_param lst) in
+            let params = String.concat ~sep:", " (List.map format_param lst) in
             (match delim with `parens -> "(" | `brackets -> "[")
             ^ params
             ^ match delim with `parens -> ")" | `brackets -> "]"))
@@ -1077,7 +1078,7 @@ module Make (Syntax : SYNTAX) = struct
             | Constraint cst -> continue @@ constraint_ cst
             | Comment `Stop ->
                 let rest =
-                  Utils.skip_until rest ~p:(function
+                  List.skip_until rest ~p:(function
                     | Lang.ClassSignature.Comment `Stop -> true
                     | _ -> false)
                 in
@@ -1268,7 +1269,7 @@ module Make (Syntax : SYNTAX) = struct
                 loop rest (List.rev_append items acc_items)
             | Comment `Stop ->
                 let rest =
-                  Utils.skip_until rest ~p:(function
+                  List.skip_until rest ~p:(function
                     | Lang.Signature.Comment `Stop -> true
                     | _ -> false)
                 in
@@ -1376,18 +1377,19 @@ module Make (Syntax : SYNTAX) = struct
       | Some params, sg ->
           let sg_doc, content = signature sg in
           let params =
-            Utils.flatmap params ~f:(fun arg ->
-                let content = functor_parameter arg in
-                let attr = [ "parameter" ] in
-                let anchor =
-                  Some
-                    (Url.Anchor.from_identifier (arg.id :> Paths.Identifier.t))
-                in
-                let doc = [] in
-                [
-                  Item.Declaration
-                    { content; anchor; attr; doc; source_anchor = None };
-                ])
+            let decl_of_arg arg =
+              let content = functor_parameter arg in
+              let attr = [ "parameter" ] in
+              let anchor =
+                Some (Url.Anchor.from_identifier (arg.id :> Paths.Identifier.t))
+              in
+              let doc = [] in
+              [
+                Item.Declaration
+                  { content; anchor; attr; doc; source_anchor = None };
+              ]
+            in
+            List.concat_map decl_of_arg params
           in
           let prelude = mk_heading ~label:"parameters" "Parameters" :: params
           and content = mk_heading ~label:"signature" "Signature" :: content in
diff --git a/src/document/utils.ml b/src/document/utils.ml
deleted file mode 100644
index 49286b8cb2..0000000000
--- a/src/document/utils.ml
+++ /dev/null
@@ -1,42 +0,0 @@
-let option_of_result = function Result.Ok x -> Some x | Result.Error _ -> None
-
-let rec flatmap ?sep ~f = function
-  | [] -> []
-  | [ x ] -> f x
-  | x :: xs -> (
-      let hd = f x in
-      let tl = flatmap ?sep ~f xs in
-      match sep with None -> hd @ tl | Some sep -> hd @ sep @ tl)
-
-let rec skip_until ~p = function
-  | [] -> []
-  | h :: t -> if p h then t else skip_until ~p t
-
-let split_at ~f lst =
-  let rec loop acc = function
-    | hd :: _ as rest when f hd -> (List.rev acc, rest)
-    | [] -> (List.rev acc, [])
-    | hd :: tl -> loop (hd :: acc) tl
-  in
-  loop [] lst
-
-let rec compute_length_source (t : Types.Source.t) : int =
-  let f (acc : int) = function
-    | Types.Source.Elt t -> acc + compute_length_inline t
-    | Types.Source.Tag (_, t) -> acc + compute_length_source t
-  in
-  List.fold_left f 0 t
-
-and compute_length_inline (t : Types.Inline.t) : int =
-  let f (acc : int) { Types.Inline.desc; _ } =
-    match desc with
-    | Text s -> acc + String.length s
-    | Entity _e -> acc + 1
-    | Linebreak -> 0 (* TODO *)
-    | Styled (_, t) | Link { content = t; _ } -> acc + compute_length_inline t
-    | Source s -> acc + compute_length_source s
-    | Math _ -> assert false
-    | Raw_markup _ -> assert false
-    (* TODO *)
-  in
-  List.fold_left f 0 t
diff --git a/src/document/utils.mli b/src/document/utils.mli
deleted file mode 100644
index 4ead7e29aa..0000000000
--- a/src/document/utils.mli
+++ /dev/null
@@ -1,6 +0,0 @@
-val option_of_result : ('a, 'b) Result.result -> 'a option
-val flatmap : ?sep:'a list -> f:('b -> 'a list) -> 'b list -> 'a list
-val skip_until : p:('a -> bool) -> 'a list -> 'a list
-val split_at : f:('a -> bool) -> 'a list -> 'a list * 'a list
-val compute_length_source : Types.Source.t -> int
-val compute_length_inline : Types.Inline.t -> int
diff --git a/src/driver/dune b/src/driver/dune
index a1e00c794b..2998e24f66 100644
--- a/src/driver/dune
+++ b/src/driver/dune
@@ -14,5 +14,4 @@
   logs
   logs.fmt
   eio_main
-  sexplib
-  odoc_utils))
+  sexplib))
diff --git a/src/driver/util.ml b/src/driver/util.ml
index 08b8a56311..8228a3f958 100644
--- a/src/driver/util.ml
+++ b/src/driver/util.ml
@@ -1,6 +1,7 @@
-open Odoc_utils
 open Bos
 
+let ( >>= ) = Result.bind
+
 module StringSet = Set.Make (String)
 module StringMap = Map.Make (String)
 
@@ -26,7 +27,6 @@ let lines_of_process cmd =
 (** Opens a file for writing and calls [f]. The destination directory is created
     if needed. *)
 let with_out_to filename f =
-  let open ResultMonad in
   let filename = Fpath.normalize filename in
   OS.Dir.create (Fpath.parent filename) >>= fun _ ->
   OS.File.with_oc filename
@@ -35,6 +35,5 @@ let with_out_to filename f =
       Ok ())
     ()
   |> Result.join
-  >>= fun () -> Ok ()
 
 let cp src dst = assert (lines_of_process Cmd.(v "cp" % src % dst) = [])
diff --git a/src/loader/odoc_loader.mli b/src/loader/odoc_loader.mli
index c593e3c9a9..b9ecd1ecfd 100644
--- a/src/loader/odoc_loader.mli
+++ b/src/loader/odoc_loader.mli
@@ -1,4 +1,3 @@
-open Result
 open Odoc_model
 open Odoc_model.Paths
 
diff --git a/src/manpage/generator.ml b/src/manpage/generator.ml
index 2853760ee8..679d69a69b 100644
--- a/src/manpage/generator.ml
+++ b/src/manpage/generator.ml
@@ -1,3 +1,4 @@
+open Odoc_utils
 module ManLink = Link
 open Odoc_document
 open Types
@@ -299,7 +300,7 @@ and inline (l : Inline.t) =
               | { Inline.desc = Text s; _ } -> Accum [ s ]
               | _ -> Stop_and_keep)
           in
-          str {|%s|} (String.concat "" l) ++ inline rest
+          str {|%s|} (String.concat ~sep:"" l) ++ inline rest
       | Entity e ->
           let x = entity e in
           x ++ inline rest
@@ -343,7 +344,7 @@ let table pp { Table.data; align } =
               | Default -> "l")
             align
     in
-    Align_line (String.concat "" alignment)
+    Align_line (String.concat ~sep:"" alignment)
   in
   env "TS" "TE" ""
     (str "allbox;" ++ alignment
@@ -408,7 +409,7 @@ let next_heading, reset_heading =
     | 1, n :: _ -> [ n + 1 ]
     | i, n :: t -> n :: succ_heading (i - 1) t
   in
-  let print_heading l = String.concat "." @@ List.map string_of_int l in
+  let print_heading l = String.concat ~sep:"." @@ List.map string_of_int l in
   let next level =
     let new_heading = succ_heading level !heading_stack in
     heading_stack := new_heading;
@@ -547,7 +548,7 @@ let page p =
   let i = Shift.compute ~on_sub p.items in
   macro "TH" {|%s 3 "" "Odoc" "OCaml Library"|} p.url.name
   ++ macro "SH" "Name"
-  ++ str "%s" (String.concat "." @@ Link.for_printing p.url)
+  ++ str "%s" (String.concat ~sep:"." @@ Link.for_printing p.url)
   ++ macro "SH" "Synopsis" ++ vspace ++ item ~nested:false header
   ++ macro "SH" "Documentation" ++ vspace ++ macro "nf" ""
   ++ item ~nested:false i
@@ -558,7 +559,7 @@ let rec subpage subp =
 
 and render_page (p : Page.t) =
   let p = Doctree.Labels.disambiguate_page ~enter_subpages:true p
-  and children = Utils.flatmap ~f:subpage @@ Subpages.compute p in
+  and children = List.concat_map subpage (Subpages.compute p) in
   let content ppf = Format.fprintf ppf "%a@." Roff.pp (page p) in
   let filename = Link.as_filename p.url in
   { Renderer.filename; content; children; path = p.url }
diff --git a/src/model/dune b/src/model/dune
index 81db5d9a0a..762fd475f5 100644
--- a/src/model/dune
+++ b/src/model/dune
@@ -16,4 +16,4 @@
   (backend landmarks --auto))
  (instrumentation
   (backend bisect_ppx))
- (libraries result compiler-libs.common odoc-parser odoc_utils))
+ (libraries compiler-libs.common odoc-parser odoc_utils))
diff --git a/src/model/error.ml b/src/model/error.ml
index 4902952970..90fdf7bc43 100644
--- a/src/model/error.ml
+++ b/src/model/error.ml
@@ -1,5 +1,3 @@
-open Result
-
 let enable_missing_root_warning = ref false
 
 type full_location_payload = Odoc_parser.Warning.t = {
@@ -90,7 +88,7 @@ let catch_warnings f =
       let warnings = List.rev !raised_warnings in
       { value; warnings })
 
-type 'a with_errors_and_warnings = ('a, t) Result.result with_warnings
+type 'a with_errors_and_warnings = ('a, t) result with_warnings
 
 let raise_errors_and_warnings we =
   match raise_warnings we with Ok x -> x | Error e -> raise_exception e
diff --git a/src/model/error.mli b/src/model/error.mli
index 83916370f4..47260488ac 100644
--- a/src/model/error.mli
+++ b/src/model/error.mli
@@ -16,7 +16,7 @@ val raise_exception : t -> _
 (** Raise a {!t} as an exception. Can be caught with {!catch} or
     {!catch_errors_and_warnings}. *)
 
-val catch : (unit -> 'a) -> ('a, t) Result.result
+val catch : (unit -> 'a) -> ('a, t) result
 
 type 'a with_warnings
 
@@ -30,7 +30,7 @@ val raise_warnings : 'a with_warnings -> 'a
 val catch_warnings : (unit -> 'a) -> 'a with_warnings
 (** Catch warnings accumulated by [raise_warning]. Safe to nest. *)
 
-type 'a with_errors_and_warnings = ('a, t) Result.result with_warnings
+type 'a with_errors_and_warnings = ('a, t) result with_warnings
 (** Subtype of [with_warnings]. *)
 
 val raise_errors_and_warnings : 'a with_errors_and_warnings -> 'a
@@ -48,14 +48,14 @@ type warnings_options = {
 val handle_warnings :
   warnings_options:warnings_options ->
   'a with_warnings ->
-  ('a, [> `Msg of string ]) Result.result
+  ('a, [> `Msg of string ]) result
 (** Print warnings to stderr. If [warn_error] is [true] and there was warnings,
     returns an [Error]. *)
 
 val handle_errors_and_warnings :
   warnings_options:warnings_options ->
   'a with_errors_and_warnings ->
-  ('a, [> `Msg of string ]) Result.result
+  ('a, [> `Msg of string ]) result
 (** Like [handle_warnings] but works on the output of
     [catch_errors_and_warnings]. Error case is converted into a [`Msg]. *)
 
diff --git a/src/model/frontmatter.ml b/src/model/frontmatter.ml
index 408873a202..fd6aa5d3b9 100644
--- a/src/model/frontmatter.ml
+++ b/src/model/frontmatter.ml
@@ -74,7 +74,7 @@ type tag_payload = Comment.nestable_block_element Location_.with_location list
 let parse_children_order loc (co : tag_payload) =
   let rec parse_words acc words =
     match words with
-    | [] -> Result.Ok (Location_.at loc (Children_order (List.rev acc)))
+    | [] -> Ok (Location_.at loc (Children_order (List.rev acc)))
     | ({ Location_.value = `Word word; _ } as w) :: tl ->
         parse_words ({ w with value = parse_child word } :: acc) tl
     | { Location_.value = `Space; _ } :: tl -> parse_words acc tl
@@ -93,7 +93,7 @@ let parse_short_title loc (t : tag_payload) =
   match t with
   | [ { Location_.value = `Paragraph words; _ } ] ->
       let short_title = Comment.link_content_of_inline_elements words in
-      Result.Ok (Location_.at loc (Short_title short_title))
+      Ok (Location_.at loc (Short_title short_title))
   | _ ->
       Error
         (Error.make
@@ -104,14 +104,14 @@ let parse_toc_status loc (t : tag_payload) =
   | [
    { Location_.value = `Paragraph [ { Location_.value = `Word "open"; _ } ]; _ };
   ] ->
-      Result.Ok (Location_.at loc (Toc_status `Open))
+      Ok (Location_.at loc (Toc_status `Open))
   | [
    {
      Location_.value = `Paragraph [ { Location_.value = `Word "hidden"; _ } ];
      _;
    };
   ] ->
-      Result.Ok (Location_.at loc (Toc_status `Hidden))
+      Ok (Location_.at loc (Toc_status `Hidden))
   | _ ->
       Error
         (Error.make "@toc_status can only take the 'open' and 'hidden' value"
@@ -121,7 +121,7 @@ let parse_order_category loc (t : tag_payload) =
   match t with
   | [ { Location_.value = `Paragraph [ { Location_.value = `Word w; _ } ]; _ } ]
     ->
-      Result.Ok (Location_.at loc (Order_category w))
+      Ok (Location_.at loc (Order_category w))
   | _ ->
       Error
         (Error.make "@order_category can only take a single word as value" loc)
diff --git a/src/model/frontmatter.mli b/src/model/frontmatter.mli
index 900179b530..ef1204e226 100644
--- a/src/model/frontmatter.mli
+++ b/src/model/frontmatter.mli
@@ -20,21 +20,21 @@ type tag_payload = Comment.nestable_block_element Location_.with_location list
 val parse_children_order :
   Location_.span ->
   tag_payload ->
-  (line Location_.with_location, Error.t) Result.result
+  (line Location_.with_location, Error.t) result
 
 val parse_short_title :
   Location_.span ->
   tag_payload ->
-  (line Location_.with_location, Error.t) Result.result
+  (line Location_.with_location, Error.t) result
 
 val parse_toc_status :
   Location_.span ->
   tag_payload ->
-  (line Location_.with_location, Error.t) Result.result
+  (line Location_.with_location, Error.t) result
 
 val parse_order_category :
   Location_.span ->
   tag_payload ->
-  (line Location_.with_location, Error.t) Result.result
+  (line Location_.with_location, Error.t) result
 
 val of_lines : line Location_.with_location list -> t Error.with_warnings
diff --git a/src/model/reference.ml b/src/model/reference.ml
index 052a2c90bd..bd162fee4a 100644
--- a/src/model/reference.ml
+++ b/src/model/reference.ml
@@ -590,8 +590,8 @@ let read_path_longident location s =
   in
   Error.catch_warnings (fun () ->
       match loop s (String.length s - 1) with
-      | Some r -> Result.Ok (r :> path)
-      | None -> Result.Error (expected_err_str "a valid path" location))
+      | Some r -> Ok (r :> path)
+      | None -> Error (expected_err_str "a valid path" location))
 
 let read_mod_longident location lid =
   Error.catch_warnings (fun () ->
@@ -601,7 +601,5 @@ let read_mod_longident location lid =
           match p with
           | (`Root (_, (`TUnknown | `TModule)) | `Dot (_, _) | `Module (_, _))
             as r ->
-              Result.Ok r
-          | _ ->
-              Result.Error (expected_err_str "a reference to a module" location)
-          ))
+              Ok r
+          | _ -> Error (expected_err_str "a reference to a module" location)))
diff --git a/src/model/semantics.ml b/src/model/semantics.ml
index 0f66efee47..6c522f4305 100644
--- a/src/model/semantics.ml
+++ b/src/model/semantics.ml
@@ -192,10 +192,10 @@ let rec inline_element :
   | { value = `Reference (kind, target, content) as value; location } -> (
       let { Location.value = target; location = target_location } = target in
       match Error.raise_warnings (Reference.parse target_location target) with
-      | Result.Ok target ->
+      | Ok target ->
           let content = non_link_inline_elements ~surrounding:value content in
           Location.at location (`Reference (target, content))
-      | Result.Error error ->
+      | Error error ->
           Error.raise_warning error;
           let placeholder =
             match kind with
@@ -238,9 +238,9 @@ let rec nestable_block_element :
             match
               Error.raise_warnings (Reference.read_mod_longident location value)
             with
-            | Result.Ok r ->
+            | Ok r ->
                 { Comment.module_reference = r; module_synopsis = None } :: acc
-            | Result.Error error ->
+            | Error error ->
                 Error.raise_warning error;
                 acc)
           [] modules
@@ -278,9 +278,9 @@ let rec nestable_block_element :
         |> Location.at location
       in
       match Error.raise_warnings (Reference.parse_asset href_location href) with
-      | Result.Ok target ->
+      | Ok target ->
           `Media (`Reference target, m, content) |> Location.at location
-      | Result.Error error -> fallback error)
+      | Error error -> fallback error)
 
 and nestable_block_elements elements = List.map nestable_block_element elements
 
@@ -290,13 +290,13 @@ let tag :
     Ast.ocamldoc_tag ->
     ( Comment.block_element with_location,
       internal_tags_removed with_location )
-    Result.result =
+    result =
  fun ~location status tag ->
   if not status.tags_allowed then
     (* Trigger a warning but do not remove the tag. Avoid turning tags into
        text that would render the same. *)
     Error.raise_warning (tags_not_allowed location);
-  let ok t = Result.Ok (Location.at location (`Tag t)) in
+  let ok t = Ok (Location.at location (`Tag t)) in
   match tag with
   | (`Author _ | `Since _ | `Version _) as tag -> ok tag
   | `Deprecated content -> ok (`Deprecated (nestable_block_elements content))
@@ -305,9 +305,9 @@ let tag :
   | `Raise (name, content) -> (
       match Error.raise_warnings (Reference.parse location name) with
       (* TODO: location for just name *)
-      | Result.Ok target ->
+      | Ok target ->
           ok (`Raise (`Reference (target, []), nestable_block_elements content))
-      | Result.Error error ->
+      | Error error ->
           Error.raise_warning error;
           let placeholder = `Code_span name in
           ok (`Raise (placeholder, nestable_block_elements content)))
@@ -455,11 +455,11 @@ let top_level_block_elements status ast_elements =
               ast_elements
         | { value = `Tag the_tag; location } -> (
             match tag ~location status the_tag with
-            | Result.Ok element ->
+            | Ok element ->
                 traverse ~top_heading_level
                   (element :: comment_elements_acc)
                   ast_elements
-            | Result.Error placeholder ->
+            | Error placeholder ->
                 traverse ~top_heading_level comment_elements_acc
                   (placeholder :: ast_elements))
         | { value = `Heading _ as heading; _ } ->
@@ -500,8 +500,8 @@ let strip_internal_tags ast : internal_tags_removed with_location list * _ =
             match
               Error.raise_warnings (Reference.read_path_longident r_location s)
             with
-            | Result.Ok path -> next (`Canonical path)
-            | Result.Error e ->
+            | Ok path -> next (`Canonical path)
+            | Error e ->
                 Error.raise_warning e;
                 loop ~start tags ast' tl))
     | ({
diff --git a/src/odoc/asset.ml b/src/odoc/asset.ml
index 57222e26d9..e87fa4c7c6 100644
--- a/src/odoc/asset.ml
+++ b/src/odoc/asset.ml
@@ -1,4 +1,5 @@
-open Or_error
+open Odoc_utils
+open ResultMonad
 
 let compile ~parent_id ~name ~output_dir =
   let open Odoc_model in
diff --git a/src/odoc/asset.mli b/src/odoc/asset.mli
index 8ac413ec54..03f6404412 100644
--- a/src/odoc/asset.mli
+++ b/src/odoc/asset.mli
@@ -1,4 +1,4 @@
-open Or_error
+open Odoc_utils
 
 val compile :
   parent_id:string ->
diff --git a/src/odoc/bin/main.ml b/src/odoc/bin/main.ml
index eea2b62cdc..9452d2d434 100644
--- a/src/odoc/bin/main.ml
+++ b/src/odoc/bin/main.ml
@@ -4,6 +4,7 @@
    output the result to. *)
 
 open Odoc_utils
+open ResultMonad
 module List = ListLabels
 open Odoc_odoc
 open Compatcmdliner
@@ -35,7 +36,7 @@ let convert_directory ?(create = false) () : Fs.Directory.t Arg.conv =
 let convert_fpath =
   let parse inp =
     match Arg.(conv_parser file) inp with
-    | Ok s -> Result.Ok (Fs.File.of_string s)
+    | Ok s -> Ok (Fs.File.of_string s)
     | Error _ as e -> e
   and print = Fpath.pp in
   Arg.conv (parse, print)
@@ -43,7 +44,7 @@ let convert_fpath =
 let convert_named_root =
   let parse inp =
     match String.cuts inp ~sep:":" with
-    | [ s1; s2 ] -> Result.Ok (s1, Fs.Directory.of_string s2)
+    | [ s1; s2 ] -> Ok (s1, Fs.Directory.of_string s2)
     | _ -> Error (`Msg "")
   in
   let print ppf (s, t) =
@@ -52,7 +53,7 @@ let convert_named_root =
   Arg.conv (parse, print)
 
 let handle_error = function
-  | Result.Ok () -> ()
+  | Ok () -> ()
   | Error (`Cli_error msg) ->
       Printf.eprintf "%s\n%!" msg;
       exit 2
@@ -84,7 +85,7 @@ module Antichain = struct
             rest
           && check rest
     in
-    if check l then Result.Ok ()
+    if check l then Ok ()
     else
       let msg =
         Format.sprintf "Paths given to all %s options must be disjoint" opt
@@ -223,7 +224,6 @@ end = struct
   let compile hidden directories resolve_fwd_refs dst output_dir package_opt
       parent_name_opt parent_id_opt open_modules children input warnings_options
       unique_id short_title =
-    let open Or_error in
     let _ =
       match unique_id with
       | Some id -> Odoc_model.Names.set_unique_ident id
@@ -474,8 +474,6 @@ module Compile_impl = struct
 end
 
 module Indexing = struct
-  open Or_error
-
   let output_file ~dst marshall =
     match (dst, marshall) with
     | Some file, `JSON
@@ -576,8 +574,6 @@ module Indexing = struct
 end
 
 module Sidebar = struct
-  open Or_error
-
   let output_file ~dst marshall =
     match (dst, marshall) with
     | Some file, `JSON when not (Fpath.has_ext "json" (Fpath.v file)) ->
@@ -667,8 +663,6 @@ end = struct
     | Some file -> Fs.File.of_string file
     | None -> Fs.File.(set_ext ".odocl" input)
 
-  open Or_error
-
   (** Find the package/library name the output is part of *)
   let find_root_of_input l o =
     let l =
@@ -1271,7 +1265,7 @@ module Odoc_html_args = struct
     let convert_remap =
       let parse inp =
         match String.cut ~sep:":" inp with
-        | Some (orig, mapped) -> Result.Ok (orig, mapped)
+        | Some (orig, mapped) -> Ok (orig, mapped)
         | _ -> Error (`Msg "Map must be of the form '<orig>:https://...'")
       and print fmt (orig, mapped) = Format.fprintf fmt "%s:%s" orig mapped in
       Arg.conv (parse, print)
@@ -1473,7 +1467,6 @@ module Depends = struct
       | Some p -> Format.fprintf pp "%a/" fmt_page p
 
     let list_dependencies input_file =
-      let open Or_error in
       Depends.for_rendering_step (Fs.Directory.of_string input_file)
       >>= fun depends ->
       List.iter depends ~f:(fun (root : Odoc_model.Root.t) ->
@@ -1557,8 +1550,6 @@ module Targets = struct
 end
 
 module Occurrences = struct
-  open Or_error
-
   let dst_of_string s =
     let f = Fs.File.of_string s in
     if not (Fs.File.has_ext ".odoc-occurrences" f) then
@@ -1650,7 +1641,6 @@ end
 module Odoc_error = struct
   let errors input =
     let open Odoc_odoc in
-    let open Or_error in
     let input = Fs.File.of_string input in
     Odoc_file.load input >>= fun unit ->
     Odoc_model.Error.print_errors unit.warnings;
diff --git a/src/odoc/compile.ml b/src/odoc/compile.ml
index 70cbadfe83..1f2278714f 100644
--- a/src/odoc/compile.ml
+++ b/src/odoc/compile.ml
@@ -1,7 +1,7 @@
+open Odoc_utils
+open ResultMonad
 open Odoc_model
 open Odoc_model.Names
-open Or_error
-open Odoc_utils
 
 (*
  * Copyright (c) 2014 Leo White <leo@lpw25.net>
diff --git a/src/odoc/compile.mli b/src/odoc/compile.mli
index 6447a2f6c0..62e6af2b06 100644
--- a/src/odoc/compile.mli
+++ b/src/odoc/compile.mli
@@ -14,9 +14,9 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  *)
 
+open Odoc_utils
 open Odoc_model
 open Odoc_model.Paths
-open Or_error
 
 type package_spec = { package : string; output : Fpath.t }
 type parent_spec = {
diff --git a/src/odoc/depends.ml b/src/odoc/depends.ml
index d6c8f521a8..d1eb392431 100644
--- a/src/odoc/depends.ml
+++ b/src/odoc/depends.ml
@@ -14,8 +14,9 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  *)
 
+open Odoc_utils
+open ResultMonad
 open StdLabels
-open Or_error
 
 module Odoc_compile = Compile
 
diff --git a/src/odoc/depends.mli b/src/odoc/depends.mli
index 0a773d6cce..1b022a14da 100644
--- a/src/odoc/depends.mli
+++ b/src/odoc/depends.mli
@@ -14,7 +14,7 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  *)
 
-open Or_error
+open Odoc_utils
 
 (** Computes the dependencies required for each step of the pipeline to work
     correctly on a given input. *)
diff --git a/src/odoc/fs.ml b/src/odoc/fs.ml
index 7cd189f036..3b79417bc5 100644
--- a/src/odoc/fs.ml
+++ b/src/odoc/fs.ml
@@ -16,7 +16,6 @@
 
 open Odoc_utils
 open StdLabels
-open Or_error
 
 type directory = Fpath.t
 
@@ -51,23 +50,22 @@ module File = struct
 
   let create ~directory ~name =
     match Fpath.of_string name with
-    | Result.Error (`Msg e) -> invalid_arg ("Odoc.Fs.File.create: " ^ e)
-    | Result.Ok psuf -> Fpath.(normalize @@ (directory // psuf))
+    | Error (`Msg e) -> invalid_arg ("Odoc.Fs.File.create: " ^ e)
+    | Ok psuf -> Fpath.(normalize @@ (directory // psuf))
 
   let to_string = Fpath.to_string
-  let segs = Fpath.segs
 
   let of_string s =
     match Fpath.of_string s with
-    | Result.Error (`Msg e) -> invalid_arg ("Odoc.Fs.File.of_string: " ^ e)
-    | Result.Ok p -> p
+    | Error (`Msg e) -> invalid_arg ("Odoc.Fs.File.of_string: " ^ e)
+    | Ok p -> p
 
   let read file =
     let input_one_shot len ic =
       let buf = Bytes.create len in
       really_input ic buf 0 len;
       close_in ic;
-      Result.Ok (Bytes.unsafe_to_string buf)
+      Ok (Bytes.unsafe_to_string buf)
     in
     let input_stream file ic =
       let bsize =
@@ -78,9 +76,9 @@ module File = struct
       let rec loop () =
         match Buffer.add_channel buf ic bsize with
         | () -> loop ()
-        | exception End_of_file -> Result.Ok (Buffer.contents buf)
+        | exception End_of_file -> Ok (Buffer.contents buf)
         | exception Failure _ ->
-            Result.Error (`Msg (Printf.sprintf "%s: input too large" file))
+            Error (`Msg (Printf.sprintf "%s: input too large" file))
       in
       loop ()
     in
@@ -95,8 +93,8 @@ module File = struct
       | len when len <= Sys.max_string_length -> input_one_shot len ic
       | len ->
           let err = Printf.sprintf "%s: file too large (%d bytes)" file len in
-          Result.Error (`Msg err)
-    with Sys_error e -> Result.Error (`Msg e)
+          Error (`Msg err)
+    with Sys_error e -> Error (`Msg e)
 
   let copy ~src ~dst =
     try
@@ -112,7 +110,7 @@ module File = struct
                   loop ())
               in
               Ok (loop ())))
-    with Sys_error e -> Result.Error (`Msg e)
+    with Sys_error e -> Error (`Msg e)
 
   let exists file = Sys.file_exists (Fpath.to_string file)
 
@@ -124,16 +122,6 @@ module File = struct
     | [] -> invalid_arg "Fs.File.of_segs"
     | "" :: rest -> of_segs_tl (Fpath.v "/") rest
     | first :: rest -> of_segs_tl (Fpath.v first) rest
-
-  let append_segs path segs = of_segs_tl path segs
-
-  module Table = Hashtbl.Make (struct
-    type nonrec t = t
-
-    let equal = Fpath.equal
-
-    let hash = Hashtbl.hash
-  end)
 end
 
 module Directory = struct
@@ -145,21 +133,6 @@ module Directory = struct
 
   let append = Fpath.append
 
-  let make_path p name =
-    match Fpath.of_string name with
-    | Result.Error _ as e -> e
-    | Result.Ok psuf ->
-        Result.Ok Fpath.(normalize @@ to_dir_path @@ (p // psuf))
-
-  let reach_from ~dir path =
-    match make_path dir path with
-    | Result.Error (`Msg e) -> invalid_arg ("Odoc.Fs.Directory.create: " ^ e)
-    | Result.Ok path ->
-        let pstr = Fpath.to_string path in
-        if Sys.file_exists pstr && not (Sys.is_directory pstr) then
-          invalid_arg "Odoc.Fs.Directory.create: not a directory";
-        path
-
   let contains ~parentdir f = Fpath.is_rooted ~root:parentdir f
 
   let compare = Fpath.compare
@@ -172,8 +145,8 @@ module Directory = struct
 
   let of_string s =
     match Fpath.of_string s with
-    | Result.Error (`Msg e) -> invalid_arg ("Odoc.Fs.Directory.of_string: " ^ e)
-    | Result.Ok p -> Fpath.to_dir_path p
+    | Error (`Msg e) -> invalid_arg ("Odoc.Fs.Directory.of_string: " ^ e)
+    | Ok p -> Fpath.to_dir_path p
 
   let of_file f = Fpath.to_dir_path f
 
@@ -207,12 +180,4 @@ module Directory = struct
     in
     try Ok (fold_files_rec ?ext f acc d)
     with Stop_iter (`Msg _ as e) -> Error e
-
-  module Table = Hashtbl.Make (struct
-    type nonrec t = t
-
-    let equal = Fpath.equal
-
-    let hash = Hashtbl.hash
-  end)
 end
diff --git a/src/odoc/fs.mli b/src/odoc/fs.mli
index 935ebc8800..3756a750db 100644
--- a/src/odoc/fs.mli
+++ b/src/odoc/fs.mli
@@ -1,4 +1,4 @@
-open Or_error
+open Odoc_utils
 
 (*
  * Copyright (c) 2016 Thomas Refis <trefis@janestreet.com>
@@ -23,8 +23,6 @@ type file = Fpath.t
 type directory
 
 module Directory : sig
-  open Or_error
-
   type t = directory
 
   val dirname : t -> t
@@ -33,9 +31,6 @@ module Directory : sig
 
   val append : t -> t -> t
 
-  val reach_from : dir:t -> string -> t
-  (** @raise Invalid_argument if [parent/name] exists but is not a directory. *)
-
   val contains : parentdir:t -> file -> bool
 
   val compare : t -> t -> int
@@ -64,8 +59,6 @@ module Directory : sig
   (** [fold_files_rec_result ~ext f acc d] recursively folds [f] over the files
       with extension matching [ext] (defaults to [""]) contained in [d] and its
       sub directories. Stop as soon as [f] returns [Error _]. *)
-
-  module Table : Hashtbl.S with type key = t
 end
 
 module File : sig
@@ -89,8 +82,6 @@ module File : sig
 
   val to_string : t -> string
 
-  val segs : t -> string list
-
   val read : t -> (string, [> msg ]) result
 
   val copy : src:t -> dst:t -> (unit, [> msg ]) result
@@ -100,9 +91,4 @@ module File : sig
   val of_segs : string list -> t
   (** [of_segs segs] Returns an absolute path if [segs] starts with an empty
       segment. Raises [Invalid_argument] if [segs] is empty. *)
-
-  val append_segs : t -> string list -> t
-  (** Append a list of segments to a path. Do not raise. *)
-
-  module Table : Hashtbl.S with type key = t
 end
diff --git a/src/odoc/html_fragment.ml b/src/odoc/html_fragment.ml
index 7189f8b1c7..07902c73f1 100644
--- a/src/odoc/html_fragment.ml
+++ b/src/odoc/html_fragment.ml
@@ -1,5 +1,5 @@
 open Odoc_utils
-open Or_error
+open ResultMonad
 
 let from_mld ~xref_base_uri ~resolver ~output ~warnings_options input =
   (* Internal names, they don't have effect on the output. *)
diff --git a/src/odoc/html_fragment.mli b/src/odoc/html_fragment.mli
index 78b0d3f465..9bf67c3b3a 100644
--- a/src/odoc/html_fragment.mli
+++ b/src/odoc/html_fragment.mli
@@ -14,7 +14,7 @@
  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  *)
 
-open Or_error
+open Odoc_utils
 
 (** Produces html fragment files from a mld file. *)
 
diff --git a/src/odoc/indexing.ml b/src/odoc/indexing.ml
index fb2874c2cc..70bde8968b 100644
--- a/src/odoc/indexing.ml
+++ b/src/odoc/indexing.ml
@@ -1,7 +1,6 @@
 open Odoc_utils
-open Astring
+open ResultMonad
 open Odoc_json_index
-open Or_error
 open Odoc_model
 
 module H = Odoc_model.Paths.Identifier.Hashtbl.Any
diff --git a/src/odoc/indexing.mli b/src/odoc/indexing.mli
index e1ffab4766..4ebf089a6f 100644
--- a/src/odoc/indexing.mli
+++ b/src/odoc/indexing.mli
@@ -1,4 +1,4 @@
-open Or_error
+open Odoc_utils
 
 val compile :
   [ `JSON | `Marshall ] ->
diff --git a/src/odoc/occurrences.ml b/src/odoc/occurrences.ml
index 330a50fc4b..655e84fbc4 100644
--- a/src/odoc/occurrences.ml
+++ b/src/odoc/occurrences.ml
@@ -1,5 +1,5 @@
 open Odoc_utils
-open Or_error
+open ResultMonad
 
 let handle_file file ~f =
   if String.is_prefix ~affix:"impl-" (Fpath.filename file) then
@@ -34,9 +34,6 @@ let count ~dst ~warnings_options:_ directories include_hidden =
   Io_utils.marshal (Fs.File.to_string dst) htbl;
   Ok ()
 
-open Astring
-open Or_error
-
 let parse_input_file input =
   let is_sep = function '\n' | '\r' -> true | _ -> false in
   Fs.File.read input >>= fun content ->
diff --git a/src/odoc/odoc_file.ml b/src/odoc/odoc_file.ml
index d07f1cf824..67f9b07098 100644
--- a/src/odoc/odoc_file.ml
+++ b/src/odoc/odoc_file.ml
@@ -15,8 +15,8 @@
  *)
 
 open Odoc_utils
+open ResultMonad
 open Odoc_model
-open Or_error
 
 type unit_content = Lang.Compilation_unit.t
 
diff --git a/src/odoc/odoc_file.mli b/src/odoc/odoc_file.mli
index 6f2c39ed58..474c1e886c 100644
--- a/src/odoc/odoc_file.mli
+++ b/src/odoc/odoc_file.mli
@@ -16,8 +16,8 @@
 
 (** Load and save [.odoc] and [.odocl] files. *)
 
+open Odoc_utils
 open Odoc_model
-open Or_error
 
 (** Either a page or a module or something else. *)
 type content =
diff --git a/src/odoc/odoc_link.ml b/src/odoc/odoc_link.ml
index 141304c8ba..f51f1fa144 100644
--- a/src/odoc/odoc_link.ml
+++ b/src/odoc/odoc_link.ml
@@ -1,4 +1,5 @@
-open Or_error
+open Odoc_utils
+open ResultMonad
 
 let link_page ~resolver ~filename page =
   let env = Resolver.build_env_for_page resolver page in
diff --git a/src/odoc/or_error.ml b/src/odoc/or_error.ml
deleted file mode 100644
index 6eaae71b4c..0000000000
--- a/src/odoc/or_error.ml
+++ /dev/null
@@ -1,9 +0,0 @@
-type ('a, 'e) result = ('a, 'e) Result.result = Ok of 'a | Error of 'e
-
-type msg = [ `Msg of string ]
-
-let ( >>= ) r f = match r with Ok v -> f v | Error _ as e -> e
-
-let rec fold_list f acc = function
-  | [] -> Ok acc
-  | hd :: tl -> f acc hd >>= fun acc -> fold_list f acc tl
diff --git a/src/odoc/or_error.mli b/src/odoc/or_error.mli
deleted file mode 100644
index 67a51c6f7e..0000000000
--- a/src/odoc/or_error.mli
+++ /dev/null
@@ -1,9 +0,0 @@
-(** Re-export for compatibility with 4.02 *)
-type ('a, 'e) result = ('a, 'e) Result.result = Ok of 'a | Error of 'e
-
-type msg = [ `Msg of string ]
-
-val ( >>= ) : ('a, 'e) result -> ('a -> ('b, 'e) result) -> ('b, 'e) result
-
-val fold_list :
-  ('acc -> 'a -> ('acc, 'e) result) -> 'acc -> 'a list -> ('acc, 'e) result
diff --git a/src/odoc/rendering.ml b/src/odoc/rendering.ml
index cccae2143b..1574e132f8 100644
--- a/src/odoc/rendering.ml
+++ b/src/odoc/rendering.ml
@@ -1,6 +1,6 @@
 open Odoc_utils
+open ResultMonad
 open Odoc_document
-open Or_error
 open Odoc_model
 
 let prepare ~extra_suffix ~output_dir filename =
diff --git a/src/odoc/rendering.mli b/src/odoc/rendering.mli
index 69c7baa704..859d20d6f2 100644
--- a/src/odoc/rendering.mli
+++ b/src/odoc/rendering.mli
@@ -1,5 +1,5 @@
+open Odoc_utils
 open Odoc_document
-open Or_error
 
 val render_odoc :
   resolver:Resolver.t ->
@@ -42,7 +42,7 @@ val generate_asset_odoc :
   extra_suffix:string option ->
   'a ->
   Fs.file ->
-  (unit, [> Or_error.msg ]) result
+  (unit, [> msg ]) result
 
 val targets_odoc :
   resolver:Resolver.t ->
@@ -62,4 +62,4 @@ val targets_source_odoc :
   extra:'a ->
   source_file:Fpath.t ->
   Fs.file ->
-  (unit, [> Or_error.msg ]) result
+  (unit, [> msg ]) result
diff --git a/src/odoc/resolver.ml b/src/odoc/resolver.ml
index 991d91b2ce..0e7eb188c4 100644
--- a/src/odoc/resolver.ml
+++ b/src/odoc/resolver.ml
@@ -32,7 +32,7 @@
    which will generally fix this issue. *)
 
 open Odoc_utils
-open Or_error
+open ResultMonad
 
 type named_root = string * Fs.Directory.t
 module Named_roots : sig
diff --git a/src/odoc/sidebar.ml b/src/odoc/sidebar.ml
index eaed81956c..c6e0cbaeaa 100644
--- a/src/odoc/sidebar.ml
+++ b/src/odoc/sidebar.ml
@@ -1,5 +1,5 @@
-open Or_error
 open Odoc_utils
+open ResultMonad
 
 let compile_to_json ~output sidebar =
   let json = Odoc_html.Sidebar.to_json sidebar in
diff --git a/src/odoc/source.ml b/src/odoc/source.ml
index fa1d79418c..aee313b15d 100644
--- a/src/odoc/source.ml
+++ b/src/odoc/source.ml
@@ -1,5 +1,6 @@
+open Odoc_utils
+open ResultMonad
 open Odoc_model
-open Or_error
 
 let resolve_and_substitute ~resolver ~make_root ~source_id input_file =
   let filename = Fs.File.to_string input_file in
diff --git a/src/parser/dune b/src/parser/dune
index e7a3d1ce4c..7d930d123d 100644
--- a/src/parser/dune
+++ b/src/parser/dune
@@ -9,4 +9,4 @@
   (backend bisect_ppx))
  (flags
   (:standard -w -50))
- (libraries astring result camlp-streams))
+ (libraries astring camlp-streams))
diff --git a/src/utils/dune b/src/utils/dune
index 598934910b..0d749d5316 100644
--- a/src/utils/dune
+++ b/src/utils/dune
@@ -1,4 +1,4 @@
 (library
  (name odoc_utils)
  (public_name odoc.odoc_utils)
- (libraries result astring))
+ (libraries astring))
diff --git a/src/utils/odoc_list.ml b/src/utils/odoc_list.ml
index 36abfa6238..057a243d77 100644
--- a/src/utils/odoc_list.ml
+++ b/src/utils/odoc_list.ml
@@ -8,6 +8,7 @@ let rec concat_map_sep ~sep ~f = function
       let tl = concat_map_sep ~sep ~f xs in
       hd @ (sep :: tl)
 
+(* Since 4.10 *)
 let concat_map f l =
   let rec aux f acc = function
     | [] -> rev acc
@@ -17,28 +18,29 @@ let concat_map f l =
   in
   aux f [] l
 
-let rec filter_map acc f = function
-  | hd :: tl ->
-      let acc = match f hd with Some x -> x :: acc | None -> acc in
-      filter_map acc f tl
-  | [] -> List.rev acc
-
-let filter_map f x = filter_map [] f x
-
 (** @raise Failure if the list is empty. *)
 let rec last = function
   | [] -> failwith "Odoc_utils.List.last"
   | [ x ] -> x
   | _ :: tl -> last tl
 
-(* From ocaml/ocaml *)
+(* Since 4.10. Copied ocaml/ocaml *)
 let rec find_map f = function
   | [] -> None
   | x :: l -> (
       match f x with Some _ as result -> result | None -> find_map f l)
 
-let rec find_opt p = function
-  | [] -> None
-  | x :: l -> if p x then Some x else find_opt p l
-
+(* Since 5.1 *)
 let is_empty = function [] -> true | _ :: _ -> false
+
+let rec skip_until ~p = function
+  | [] -> []
+  | h :: t -> if p h then t else skip_until ~p t
+
+let split_at ~f lst =
+  let rec loop acc = function
+    | hd :: _ as rest when f hd -> (List.rev acc, rest)
+    | [] -> (List.rev acc, [])
+    | hd :: tl -> loop (hd :: acc) tl
+  in
+  loop [] lst
diff --git a/src/utils/odoc_utils.ml b/src/utils/odoc_utils.ml
index 2f8c11888f..c3edc618ad 100644
--- a/src/utils/odoc_utils.ml
+++ b/src/utils/odoc_utils.ml
@@ -1,80 +1,24 @@
-(** Re-export for compatibility with 4.02. *)
-type ('a, 'b) result = ('a, 'b) Result.result = Ok of 'a | Error of 'b
+type msg = [ `Msg of string ]
 
 (** The [result] type and a bind operator. This module is meant to be opened. *)
 module ResultMonad = struct
-  (** Re-export for compat *)
-  type ('a, 'b) result = ('a, 'b) Result.result = Ok of 'a | Error of 'b
-
   let map_error f = function Ok _ as ok -> ok | Error e -> Error (f e)
 
   let of_option ~error = function Some x -> Ok x | None -> Error error
 
-  let bind m f = match m with Ok x -> f x | Error _ as e -> e
-
-  let ( >>= ) = bind
+  let ( >>= ) = Result.bind
 end
 
 (** A bind operator for the [option] type. This module is meant to be opened. *)
 module OptionMonad = struct
   (* The error case become [None], the error value is ignored. *)
-  let of_result = function Result.Ok x -> Some x | Error _ -> None
-
-  let return x = Some x
+  let of_result = function Ok x -> Some x | Error _ -> None
 
-  let bind m f = match m with Some x -> f x | None -> None
-
-  let ( >>= ) = bind
-end
-
-module EitherMonad = struct
-  type ('a, 'b) t = Left of 'a | Right of 'b
-
-  let return x = Right x
-
-  let return_left x = Left x
-
-  let bind m f = match m with Right x -> f x | Left y -> Left y
-
-  let bind_left m f = match m with Left x -> f x | Right y -> Right y
-
-  let ( >>= ) = bind
-
-  let of_option ~left = function Some x -> Right x | None -> Left left
-
-  let of_result = function Result.Ok x -> Right x | Error y -> Left y
+  let ( >>= ) = Option.bind
 end
 
 module List = Odoc_list
 
-module Option = struct
-  let map f = function None -> None | Some x -> Some (f x)
-
-  let is_some = function None -> false | Some _ -> true
-end
-
-module Result = struct
-  include Result
-
-  let join = function Ok r -> r | Error _ as e -> e
-end
-
-module Fun = struct
-  exception Finally_raised of exn
-
-  let protect ~(finally : unit -> unit) work =
-    let finally_no_exn () =
-      try finally () with e -> raise (Finally_raised e)
-    in
-    match work () with
-    | result ->
-        finally_no_exn ();
-        result
-    | exception work_exn ->
-        finally_no_exn ();
-        raise work_exn
-end
-
 module Tree = Tree
 module Forest = Tree.Forest
 module Json = Json
diff --git a/src/xref2/env.ml b/src/xref2/env.ml
index c3f5b28ecc..0ef9963fe3 100644
--- a/src/xref2/env.ml
+++ b/src/xref2/env.ml
@@ -479,7 +479,7 @@ type 'a scope = {
   root : string -> t -> 'a option;
 }
 
-type 'a maybe_ambiguous = ('a, [ 'a amb_err | `Not_found ]) Result.result
+type 'a maybe_ambiguous = ('a, [ 'a amb_err | `Not_found ]) result
 
 let make_scope ?(root = fun _ _ -> None) ?check
     (filter : _ -> ([< Component.Element.any ] as 'a) option) : 'a scope =
@@ -503,12 +503,10 @@ let lookup_by_name scope name env =
   with
   | ([ x ] as results), Some c -> (
       record_lookup_results env results;
-      match c env x with
-      | Some (`Ambiguous _ as e) -> Result.Error e
-      | None -> Result.Ok x)
+      match c env x with Some (`Ambiguous _ as e) -> Error e | None -> Ok x)
   | ([ x ] as results), None ->
       record_lookup_results env results;
-      Result.Ok x
+      Ok x
   | (x :: tl as results), _ ->
       record_lookup_results env results;
       Error (`Ambiguous (x, tl))
diff --git a/src/xref2/env.mli b/src/xref2/env.mli
index d43fe8f9f3..fdb1b36bd7 100644
--- a/src/xref2/env.mli
+++ b/src/xref2/env.mli
@@ -2,7 +2,6 @@
 
 open Odoc_model
 open Odoc_model.Paths
-open Odoc_utils
 
 type lookup_unit_result = Forward_reference | Found of Lang.Compilation_unit.t
 
@@ -116,7 +115,7 @@ type 'a scope constraint 'a = [< Component.Element.any ]
 (** Target of a lookup *)
 
 type 'a maybe_ambiguous =
-  ('a, [ `Ambiguous of 'a * 'a list | `Not_found ]) Result.result
+  ('a, [ `Ambiguous of 'a * 'a list | `Not_found ]) result
 
 val lookup_by_name : 'a scope -> string -> t -> 'a maybe_ambiguous
 (** Lookup an element in Env depending on the given [scope]. Return
diff --git a/src/xref2/expand_tools.ml b/src/xref2/expand_tools.ml
index c452ff64ab..81d0280782 100644
--- a/src/xref2/expand_tools.ml
+++ b/src/xref2/expand_tools.ml
@@ -25,7 +25,7 @@ let handle_expansion env id expansion =
         (env', Subst.module_type_expr subst expr)
   in
   let rec expand id env expansion :
-      (Env.t * Component.ModuleType.simple_expansion, _) Result.result =
+      (Env.t * Component.ModuleType.simple_expansion, _) result =
     match expansion with
     | Tools.Signature sg ->
         Ok
diff --git a/src/xref2/link.ml b/src/xref2/link.ml
index bb3d0eec90..f8c55a9d5f 100644
--- a/src/xref2/link.ml
+++ b/src/xref2/link.ml
@@ -761,7 +761,7 @@ and handle_fragments env id sg subs =
   List.fold_left
     (fun (sg_res, subs) lsub ->
       match (sg_res, lsub) with
-      | Result.Ok sg, ModuleEq (frag, decl) ->
+      | Ok sg, ModuleEq (frag, decl) ->
           let frag' =
             match frag with
             | `Resolved f ->
diff --git a/src/xref2/ref_tools.ml b/src/xref2/ref_tools.ml
index b00b73d444..7fae1614e6 100644
--- a/src/xref2/ref_tools.ml
+++ b/src/xref2/ref_tools.ml
@@ -39,8 +39,7 @@ type label_parent_lookup_result =
 type fragment_type_parent_lookup_result =
   [ `S of signature_lookup_result | `T of datatype_lookup_result ]
 
-type 'a ref_result =
-  ('a, Errors.Tools_error.reference_lookup_error) Result.result
+type 'a ref_result = ('a, Errors.Tools_error.reference_lookup_error) result
 (** The result type for every functions in this module. *)
 
 let kind_of_find_result = function
diff --git a/src/xref2/ref_tools.mli b/src/xref2/ref_tools.mli
index 5b0924641f..24366c70bb 100644
--- a/src/xref2/ref_tools.mli
+++ b/src/xref2/ref_tools.mli
@@ -5,8 +5,7 @@ type module_lookup_result =
 
 type asset_lookup_result = Resolved.Asset.t
 
-type 'a ref_result =
-  ('a, Errors.Tools_error.reference_lookup_error) Result.result
+type 'a ref_result = ('a, Errors.Tools_error.reference_lookup_error) result
 
 val resolve_module_reference :
   Env.t ->
diff --git a/src/xref2/tools.ml b/src/xref2/tools.ml
index 82eac8ca8d..fbd85602b6 100644
--- a/src/xref2/tools.ml
+++ b/src/xref2/tools.ml
@@ -214,25 +214,23 @@ open Errors.Tools_error
 type resolve_module_result =
   ( Cpath.Resolved.module_ * Component.Module.t Component.Delayed.t,
     simple_module_lookup_error )
-  Result.result
+  result
 
 type resolve_module_type_result =
   ( Cpath.Resolved.module_type * Component.ModuleType.t,
     simple_module_type_lookup_error )
-  Result.result
+  result
 
 type resolve_type_result =
-  ( Cpath.Resolved.type_ * Find.careful_type,
-    simple_type_lookup_error )
-  Result.result
+  (Cpath.Resolved.type_ * Find.careful_type, simple_type_lookup_error) result
 
 type resolve_value_result =
-  (Cpath.Resolved.value * Find.value, simple_value_lookup_error) Result.result
+  (Cpath.Resolved.value * Find.value, simple_value_lookup_error) result
 
 type resolve_class_type_result =
   ( Cpath.Resolved.class_type * Find.careful_class,
     simple_type_lookup_error )
-  Result.result
+  result
 
 type ('a, 'b, 'c) sig_map = { type_ : 'a; module_ : 'b; module_type : 'c }
 
@@ -285,7 +283,7 @@ module LookupModuleMemo = MakeMemo (struct
   type result =
     ( Component.Module.t Component.Delayed.t,
       simple_module_lookup_error )
-    Result.result
+    Result.t
 
   let equal = ( = )
 
@@ -298,7 +296,7 @@ module LookupParentMemo = MakeMemo (struct
   type result =
     ( Component.Signature.t * Component.Substitution.t,
       [ `Parent of parent_lookup_error ] )
-    Result.result
+    Result.t
 
   let equal = ( = )
 
@@ -328,7 +326,7 @@ end)
 module ExpansionOfModuleMemo = MakeMemo (struct
   type t = Cpath.Resolved.module_
 
-  type result = (expansion, expansion_of_module_error) Result.result
+  type result = (expansion, expansion_of_module_error) Result.t
 
   let equal = ( = )
 
@@ -552,9 +550,8 @@ and handle_class_type_lookup id p sg =
 and lookup_module_gpath :
     Env.t ->
     Odoc_model.Paths.Path.Resolved.Module.t ->
-    ( Component.Module.t Component.Delayed.t,
-      simple_module_lookup_error )
-    Result.result =
+    (Component.Module.t Component.Delayed.t, simple_module_lookup_error) result
+    =
  fun env path ->
   match path with
   | `Identifier i ->
@@ -589,9 +586,8 @@ and lookup_module_gpath :
 and lookup_module :
     Env.t ->
     Cpath.Resolved.module_ ->
-    ( Component.Module.t Component.Delayed.t,
-      simple_module_lookup_error )
-    Result.result =
+    (Component.Module.t Component.Delayed.t, simple_module_lookup_error) result
+    =
  fun env' path' ->
   let lookup env (path : ExpansionOfModuleMemo.M.key) =
     match path with
@@ -630,7 +626,7 @@ and lookup_module :
 and lookup_module_type_gpath :
     Env.t ->
     Odoc_model.Paths.Path.Resolved.ModuleType.t ->
-    (Component.ModuleType.t, simple_module_type_lookup_error) Result.result =
+    (Component.ModuleType.t, simple_module_type_lookup_error) result =
  fun env path ->
   match path with
   | `Identifier i ->
@@ -655,7 +651,7 @@ and lookup_module_type_gpath :
 and lookup_module_type :
     Env.t ->
     Cpath.Resolved.module_type ->
-    (Component.ModuleType.t, simple_module_type_lookup_error) Result.result =
+    (Component.ModuleType.t, simple_module_type_lookup_error) result =
  fun env path ->
   let lookup env =
     match path with
@@ -682,7 +678,7 @@ and lookup_parent :
     Cpath.Resolved.parent ->
     ( Component.Signature.t * Component.Substitution.t,
       [ `Parent of parent_lookup_error ] )
-    Result.result =
+    result =
  fun env' parent' ->
   let lookup env parent =
     match parent with
@@ -714,7 +710,7 @@ and lookup_parent_gpath :
     Odoc_model.Paths.Path.Resolved.Module.t ->
     ( Component.Signature.t * Component.Substitution.t,
       [ `Parent of parent_lookup_error ] )
-    Result.result =
+    result =
  fun env parent ->
   lookup_module_gpath env parent
   |> map_error (fun e -> `Parent (`Parent_module e))
@@ -728,7 +724,7 @@ and lookup_parent_gpath :
 and lookup_type_gpath :
     Env.t ->
     Odoc_model.Paths.Path.Resolved.Type.t ->
-    (Find.careful_type, simple_type_lookup_error) Result.result =
+    (Find.careful_type, simple_type_lookup_error) result =
  fun env p ->
   let do_type p name =
     lookup_parent_gpath env p
@@ -774,7 +770,7 @@ and lookup_type_gpath :
 and lookup_value_gpath :
     Env.t ->
     Odoc_model.Paths.Path.Resolved.Value.t ->
-    (Find.value, simple_value_lookup_error) Result.result =
+    (Find.value, simple_value_lookup_error) result =
  fun env p ->
   let do_value p name =
     lookup_parent_gpath env p
@@ -797,7 +793,7 @@ and lookup_value_gpath :
 and lookup_class_type_gpath :
     Env.t ->
     Odoc_model.Paths.Path.Resolved.ClassType.t ->
-    (Find.careful_class, simple_type_lookup_error) Result.result =
+    (Find.careful_class, simple_type_lookup_error) result =
  fun env p ->
   let do_type p name =
     lookup_parent_gpath env p
@@ -831,7 +827,7 @@ and lookup_class_type_gpath :
 and lookup_type :
     Env.t ->
     Cpath.Resolved.type_ ->
-    (Find.careful_type, simple_type_lookup_error) Result.result =
+    (Find.careful_type, simple_type_lookup_error) result =
  fun env p ->
   let do_type p name =
     lookup_parent env p |> map_error (fun e -> (e :> simple_type_lookup_error))
@@ -862,9 +858,7 @@ and lookup_type :
   res
 
 and lookup_value :
-    Env.t ->
-    Cpath.Resolved.value ->
-    (_, simple_value_lookup_error) Result.result =
+    Env.t -> Cpath.Resolved.value -> (_, simple_value_lookup_error) result =
  fun env p ->
   match p with
   | `Value (p, id) ->
@@ -878,7 +872,7 @@ and lookup_value :
 and lookup_class_type :
     Env.t ->
     Cpath.Resolved.class_type ->
-    (Find.careful_class, simple_type_lookup_error) Result.result =
+    (Find.careful_class, simple_type_lookup_error) result =
  fun env p ->
   let do_type p name =
     lookup_parent env p |> map_error (fun e -> (e :> simple_type_lookup_error))
@@ -1522,9 +1516,8 @@ and reresolve_parent : Env.t -> Cpath.Resolved.parent -> Cpath.Resolved.parent =
 and module_type_expr_of_module_decl :
     Env.t ->
     Component.Module.decl ->
-    ( Component.ModuleType.expr,
-      simple_module_type_expr_of_module_error )
-    Result.result =
+    (Component.ModuleType.expr, simple_module_type_expr_of_module_error) result
+    =
  fun env decl ->
   match decl with
   | Component.Module.Alias (`Resolved r, _) ->
@@ -1545,16 +1538,15 @@ and module_type_expr_of_module_decl :
 and module_type_expr_of_module :
     Env.t ->
     Component.Module.t ->
-    ( Component.ModuleType.expr,
-      simple_module_type_expr_of_module_error )
-    Result.result =
+    (Component.ModuleType.expr, simple_module_type_expr_of_module_error) result
+    =
  fun env m -> module_type_expr_of_module_decl env m.type_
 
 and expansion_of_module_path :
     Env.t ->
     strengthen:bool ->
     Cpath.module_ ->
-    (expansion, expansion_of_module_error) Result.result =
+    (expansion, expansion_of_module_error) result =
  fun env ~strengthen path ->
   match resolve_module env path with
   | Ok (p', m) -> (
@@ -1578,7 +1570,7 @@ and handle_signature_with_subs :
     Env.t ->
     Component.Signature.t ->
     Component.ModuleType.substitution list ->
-    (Component.Signature.t, expansion_of_module_error) Result.result =
+    (Component.Signature.t, expansion_of_module_error) result =
  fun env sg subs ->
   let open Odoc_utils.ResultMonad in
   List.fold_left
@@ -1586,7 +1578,7 @@ and handle_signature_with_subs :
     (Ok sg) subs
 
 and assert_not_functor : type err.
-    expansion -> (Component.Signature.t, err) Result.result = function
+    expansion -> (Component.Signature.t, err) result = function
   | Signature sg -> Ok sg
   | _ -> assert false
 
@@ -1605,7 +1597,7 @@ and signature_of_module_type_of :
     Env.t ->
     Component.ModuleType.type_of_desc ->
     original_path:Cpath.module_ ->
-    (expansion, expansion_of_module_error) Result.result =
+    (expansion, expansion_of_module_error) result =
  fun env desc ~original_path:_ ->
   let p, strengthen =
     match desc with ModPath p -> (p, false) | StructInclude p -> (p, true)
@@ -1625,7 +1617,7 @@ and signature_of_module_type_of :
 and signature_of_u_module_type_expr :
     Env.t ->
     Component.ModuleType.U.expr ->
-    (Component.Signature.t, expansion_of_module_error) Result.result =
+    (Component.Signature.t, expansion_of_module_error) result =
  fun env m ->
   match m with
   | Component.ModuleType.U.Path p -> (
@@ -1655,7 +1647,7 @@ and expansion_of_simple_expansion :
 and expansion_of_module_type_expr :
     Env.t ->
     Component.ModuleType.expr ->
-    (expansion, expansion_of_module_error) Result.result =
+    (expansion, expansion_of_module_error) result =
  fun env m ->
   match m with
   | Component.ModuleType.Path { p_expansion = Some e; _ } ->
@@ -1685,7 +1677,7 @@ and expansion_of_module_type_expr :
 and expansion_of_module_type :
     Env.t ->
     Component.ModuleType.t ->
-    (expansion, expansion_of_module_error) Result.result =
+    (expansion, expansion_of_module_error) result =
  fun env m ->
   match m.expr with
   | None -> Error `OpaqueModule
@@ -1694,7 +1686,7 @@ and expansion_of_module_type :
 and expansion_of_module_decl :
     Env.t ->
     Component.Module.decl ->
-    (expansion, expansion_of_module_error) Result.result =
+    (expansion, expansion_of_module_error) result =
  fun env decl ->
   match decl with
   (* | Component.Module.Alias (_, Some e) -> Ok (expansion_of_simple_expansion e) *)
@@ -1703,9 +1695,8 @@ and expansion_of_module_decl :
   | Component.Module.ModuleType expr -> expansion_of_module_type_expr env expr
 
 and expansion_of_module :
-    Env.t ->
-    Component.Module.t ->
-    (expansion, expansion_of_module_error) Result.result =
+    Env.t -> Component.Module.t -> (expansion, expansion_of_module_error) result
+    =
  fun env m ->
   expansion_of_module_decl env m.type_ >>= function
   | Signature sg ->
@@ -1723,7 +1714,7 @@ and expansion_of_module_cached :
     Env.t ->
     Cpath.Resolved.module_ ->
     Component.Module.t ->
-    (expansion, expansion_of_module_error) Result.result =
+    (expansion, expansion_of_module_error) result =
  fun env' path m ->
   let id = path in
   let run env _id = expansion_of_module env m in
@@ -1773,7 +1764,7 @@ and fragmap :
     Env.t ->
     Component.ModuleType.substitution ->
     Component.Signature.t ->
-    (Component.Signature.t, expansion_of_module_error) Result.result =
+    (Component.Signature.t, expansion_of_module_error) result =
  fun env sub sg ->
   (* Used when we haven't finished the substitution. For example, if the
      substitution is `M.t = u`, this function is used to map the declaration
@@ -2117,9 +2108,8 @@ and find_module_with_replacement :
     Env.t ->
     Component.Signature.t ->
     ModuleName.t ->
-    ( Component.Module.t Component.Delayed.t,
-      simple_module_lookup_error )
-    Result.result =
+    (Component.Module.t Component.Delayed.t, simple_module_lookup_error) result
+    =
  fun env sg name ->
   match Find.careful_module_in_sig sg name with
   | Some (`FModule (_, m)) -> Ok (Component.Delayed.put_val m)
@@ -2133,7 +2123,7 @@ and find_module_type_with_replacement :
     ModuleTypeName.t ->
     ( Component.ModuleType.t Component.Delayed.t,
       simple_module_type_lookup_error )
-    Result.result =
+    result =
  fun _env sg name ->
   match Find.careful_module_type_in_sig sg name with
   | Some (`FModuleType (_, m)) -> Ok (Component.Delayed.put_val m)
diff --git a/src/xref2/tools.mli b/src/xref2/tools.mli
index b5d17fe7bb..0a0c78c886 100644
--- a/src/xref2/tools.mli
+++ b/src/xref2/tools.mli
@@ -46,23 +46,21 @@ type expansion =
 val lookup_module :
   Env.t ->
   Cpath.Resolved.module_ ->
-  ( Component.Module.t Component.Delayed.t,
-    simple_module_lookup_error )
-  Result.result
+  (Component.Module.t Component.Delayed.t, simple_module_lookup_error) result
 (** [lookup_module ~mark_substituted env p] takes a resolved module cpath [p]
     and an environment and returns a representation of the module. *)
 
 val lookup_module_type :
   Env.t ->
   Cpath.Resolved.module_type ->
-  (Component.ModuleType.t, simple_module_type_lookup_error) Result.result
+  (Component.ModuleType.t, simple_module_type_lookup_error) result
 (** [lookup_module_type ~mark_substituted env p] takes a resolved module type
     cpath and an environment and returns a representation of the module type. *)
 
 val lookup_type :
   Env.t ->
   Cpath.Resolved.type_ ->
-  (Find.careful_type, simple_type_lookup_error) Result.result
+  (Find.careful_type, simple_type_lookup_error) result
 (** [lookup_type env p] takes a resolved type path and an environment and
     returns a representation of the type. The type can be an ordinary type, a
     class type or a class. If the type has been destructively substituted, the
@@ -71,7 +69,7 @@ val lookup_type :
 val lookup_class_type :
   Env.t ->
   Cpath.Resolved.class_type ->
-  (Find.careful_class, simple_type_lookup_error) Result.result
+  (Find.careful_class, simple_type_lookup_error) result
 (** [lookup_class_type env p] takes a resolved class type path and an
     environment and returns a representation of the class type. The type can be
     a class type or a class. *)
@@ -81,7 +79,7 @@ val resolve_module :
   Cpath.module_ ->
   ( Cpath.Resolved.module_ * Component.Module.t Component.Delayed.t,
     simple_module_lookup_error )
-  Result.result
+  result
 (** [resolve_module ~mark_substituted ~add_canonical env p] takes an unresolved
     module path and an environment and returns a tuple of the resolved module
     path alongside a representation of the module itself. *)
@@ -91,7 +89,7 @@ val resolve_module_type :
   Cpath.module_type ->
   ( Cpath.Resolved.module_type * Component.ModuleType.t,
     simple_module_type_lookup_error )
-  Result.result
+  result
 (** [resolve_module_type ~mark_substituted ~add_canonical env p] takes an
     unresolved module type path and an environment and returns a tuple of the
     resolved module type path alongside a representation of the module type
@@ -100,9 +98,7 @@ val resolve_module_type :
 val resolve_type :
   Env.t ->
   Cpath.type_ ->
-  ( Cpath.Resolved.type_ * Find.careful_type,
-    simple_type_lookup_error )
-  Result.result
+  (Cpath.Resolved.type_ * Find.careful_type, simple_type_lookup_error) result
 (** [resolve_type env p] takes an unresolved type path and an environment and
     returns a tuple of the resolved type path alongside a representation of the
     type itself. As with {!val:lookup_type} the returned type is either the
@@ -114,7 +110,7 @@ val resolve_class_type :
   Cpath.class_type ->
   ( Cpath.Resolved.class_type * Find.careful_class,
     simple_type_lookup_error )
-  Result.result
+  result
 (** [resolve_class_type env p] takes an unresolved class type path and an
     environment and returns a tuple of the resolved class type path alongside a
     representation of the class type itself. As with {!val:lookup_type} the
@@ -132,27 +128,27 @@ val resolve_class_type :
 val resolve_module_path :
   Env.t ->
   Cpath.module_ ->
-  (Cpath.Resolved.module_, simple_module_lookup_error) Result.result
+  (Cpath.Resolved.module_, simple_module_lookup_error) result
 
 val resolve_module_type_path :
   Env.t ->
   Cpath.module_type ->
-  (Cpath.Resolved.module_type, simple_module_type_lookup_error) Result.result
+  (Cpath.Resolved.module_type, simple_module_type_lookup_error) result
 
 val resolve_type_path :
   Env.t ->
   Cpath.type_ ->
-  (Cpath.Resolved.type_, simple_type_lookup_error) Result.result
+  (Cpath.Resolved.type_, simple_type_lookup_error) result
 
 val resolve_value_path :
   Env.t ->
   Cpath.value ->
-  (Cpath.Resolved.value, simple_value_lookup_error) Result.result
+  (Cpath.Resolved.value, simple_value_lookup_error) result
 
 val resolve_class_type_path :
   Env.t ->
   Cpath.class_type ->
-  (Cpath.Resolved.class_type, simple_type_lookup_error) Result.result
+  (Cpath.Resolved.class_type, simple_type_lookup_error) result
 
 (** {2 Re-resolve functions} *)
 
@@ -203,24 +199,21 @@ val get_module_type_path_modifiers :
 val prefix_signature :
   Cpath.Resolved.parent * Component.Signature.t -> Component.Signature.t
 
-val assert_not_functor :
-  expansion -> (Component.Signature.t, 'err) Result.result
+val assert_not_functor : expansion -> (Component.Signature.t, 'err) result
 
 val expansion_of_module_path :
   Env.t ->
   strengthen:bool ->
   Cpath.module_ ->
-  (expansion, expansion_of_module_error) Result.result
+  (expansion, expansion_of_module_error) result
 
 val expansion_of_module :
-  Env.t ->
-  Component.Module.t ->
-  (expansion, expansion_of_module_error) Result.result
+  Env.t -> Component.Module.t -> (expansion, expansion_of_module_error) result
 
 val expansion_of_module_type :
   Env.t ->
   Component.ModuleType.t ->
-  (expansion, expansion_of_module_error) Result.result
+  (expansion, expansion_of_module_error) result
 
 val class_signature_of_class_type :
   Env.t -> Component.ClassType.t -> Component.ClassSignature.t option
@@ -233,7 +226,7 @@ val class_signature_of_class :
 val expansion_of_module_type_expr :
   Env.t ->
   Component.ModuleType.expr ->
-  (expansion, expansion_of_module_error) Result.result
+  (expansion, expansion_of_module_error) result
 (** The following functions are use for the resolution of
     {{!type:Odoc_model.Paths.Fragment.t}Fragments} Whilst resolving fragments it
     is necessary to process them in order, applying the 'with' expression of
@@ -247,7 +240,7 @@ val expansion_of_module_type_expr :
 val signature_of_u_module_type_expr :
   Env.t ->
   Component.ModuleType.U.expr ->
-  (Component.Signature.t, expansion_of_module_error) Result.result
+  (Component.Signature.t, expansion_of_module_error) result
 (** The following functions are use for the resolution of
     {{!type:Odoc_model.Paths.Fragment.t}Fragments} Whilst resolving fragments it
     is necessary to process them in order, applying the 'with' expression of
@@ -320,7 +313,7 @@ val fragmap :
   Env.t ->
   Component.ModuleType.substitution ->
   Component.Signature.t ->
-  (Component.Signature.t, expansion_of_module_error) Result.result
+  (Component.Signature.t, expansion_of_module_error) result
 (** [fragmap ~mark_substituted env sub sg] takes an environment [env] and
     signature [sg], and a fragment substitution (e.g. [ModuleSubst] to
     destructively substitute a module), and returns the substituted signature.
@@ -330,7 +323,7 @@ val handle_signature_with_subs :
   Env.t ->
   Component.Signature.t ->
   Component.ModuleType.substitution list ->
-  (Component.Signature.t, expansion_of_module_error) Result.result
+  (Component.Signature.t, expansion_of_module_error) result
 (** [handle_signature_with_subs ~mark_substituted env sg subs] applies the
     fragment modifiers [subs], in order, to the supplied signature [sg]. *)
 
diff --git a/test/odoc_print/odoc_print.ml b/test/odoc_print/odoc_print.ml
index f29a1e0f49..40bb8a38cd 100644
--- a/test/odoc_print/odoc_print.ml
+++ b/test/odoc_print/odoc_print.ml
@@ -1,7 +1,8 @@
 (** Print .odocl files. *)
 
+open Odoc_utils
+open ResultMonad
 open Odoc_odoc
-open Odoc_odoc.Or_error
 open Odoc_model_desc
 
 let print_json_desc desc x =
diff --git a/test/odoc_print/print_index.ml b/test/odoc_print/print_index.ml
index 0f104ca137..69451fdd86 100644
--- a/test/odoc_print/print_index.ml
+++ b/test/odoc_print/print_index.ml
@@ -4,7 +4,7 @@ let run inp =
   let inp = Fpath.v inp in
   let index =
     Odoc_odoc.Odoc_file.load_index inp |> function
-    | Result.Ok x -> x
+    | Ok x -> x
     | _ -> failwith "failed to load index"
   in
   let rec tree_to_yojson
diff --git a/test/xref2/resolve/test.md b/test/xref2/resolve/test.md
index e9e8100065..8f2288adf7 100644
--- a/test/xref2/resolve/test.md
+++ b/test/xref2/resolve/test.md
@@ -62,7 +62,7 @@ which takes a `Model.Lang.Signature.t` and runs the resolve mapping functions
 over the tree. For this example the interesting point comes when we get to
 looking at the manifest for type `u`. We see that we have a `Constr` that has a
 path in it, so we look up the component from the path via the function
-`Tools.lookup_type_from_model_path`. This returns us a `Result.result`
+`Tools.lookup_type_from_model_path`. This returns us a `result`
 containing the resolved path and the `Component.Type.t` that represents the
 type `t`. We don't particularly care about this, but the returned path we use
 in place of the path we had before.