diff --git a/.ocamlformat b/.ocamlformat
new file mode 100644
index 0000000..2124d7d
--- /dev/null
+++ b/.ocamlformat
@@ -0,0 +1,15 @@
+version = 0.24.1
+profile=conventional
+margin=80
+if-then-else=k-r
+parens-ite=true
+parens-tuple=multi-line-only
+sequence-style=terminator
+type-decl=sparse
+break-cases=toplevel
+cases-exp-indent=2
+field-space=tight-decl
+leading-nested-match-parens=true
+module-item-spacing=compact
+quiet=true
+ocaml-version=4.08.0
diff --git a/src/core/Ezcurl_core.ml b/src/core/Ezcurl_core.ml
index 5e573a0..06e6be2 100644
--- a/src/core/Ezcurl_core.ml
+++ b/src/core/Ezcurl_core.ml
@@ -1,4 +1,6 @@
-let opt_iter ~f = function None -> () | Some x -> f x
+let opt_iter ~f = function
+  | None -> ()
+  | Some x -> f x
 
 module Config = struct
   type t = {
@@ -11,22 +13,23 @@ module Config = struct
     user_agent: string option;
   }
 
-  let default : t = {
-    verbose=false;
-    max_redirects = 50;
-    follow_location=true;
-    authmethod=None;
-    username=None;
-    password=None;
-    user_agent=Some "curl";
-  }
+  let default : t =
+    {
+      verbose = false;
+      max_redirects = 50;
+      follow_location = true;
+      authmethod = None;
+      username = None;
+      password = None;
+      user_agent = Some "curl";
+    }
 
-  let password x self = {self with password=Some x}
-  let username x self = {self with username=Some x}
-  let verbose x self = { self with verbose=x}
-  let follow_location x self = {self with follow_location=x}
-  let max_redirects x self = {self with max_redirects=max 1 x}
-  let authmethod x self = {self with authmethod=Some x}
+  let password x self = { self with password = Some x }
+  let username x self = { self with username = Some x }
+  let verbose x self = { self with verbose = x }
+  let follow_location x self = { self with follow_location = x }
+  let max_redirects x self = { self with max_redirects = max 1 x }
+  let authmethod x self = { self with authmethod = Some x }
 
   let string_of_authmethod = function
     | Curl.CURLAUTH_ANY -> "any"
@@ -40,31 +43,39 @@ module Config = struct
     | None -> "<none>"
     | Some s -> s
 
-  let pp out (self:t) =
+  let pp out (self : t) =
     let {
-      verbose; authmethod; max_redirects; follow_location;
-      username; password; user_agent
-    } = self in
+      verbose;
+      authmethod;
+      max_redirects;
+      follow_location;
+      username;
+      password;
+      user_agent;
+    } =
+      self
+    in
     Format.fprintf out
-      "{@[verbose=%B;@ max_redirects=%d;@ follow_location=%B;@ \
-       username=%s;@ password=%s;@ authmethod=%s;@ user_agent=%s@]}"
-      verbose max_redirects follow_location
-      (str_of_str_opt username) (str_of_str_opt password)
+      "{@[verbose=%B;@ max_redirects=%d;@ follow_location=%B;@ username=%s;@ \
+       password=%s;@ authmethod=%s;@ user_agent=%s@]}"
+      verbose max_redirects follow_location (str_of_str_opt username)
+      (str_of_str_opt password)
       (match authmethod with
-       | None -> "none"
-       | Some l -> List.map string_of_authmethod l |> String.concat ",") (str_of_str_opt user_agent)
+      | None -> "none"
+      | Some l -> List.map string_of_authmethod l |> String.concat ",")
+      (str_of_str_opt user_agent)
 
   let to_string s = Format.asprintf "%a" pp s
 end
 
 type t = Curl.t
 
-let _init = lazy (
-  Curl.global_init Curl.CURLINIT_GLOBALALL;
-  at_exit Curl.global_cleanup;
-)
+let _init =
+  lazy
+    (Curl.global_init Curl.CURLINIT_GLOBALALL;
+     at_exit Curl.global_cleanup)
 
-let make ?(set_opts=fun _ -> ()) () : t =
+let make ?(set_opts = fun _ -> ()) () : t =
   Lazy.force _init;
   let c = Curl.init () in
   Gc.finalise Curl.cleanup c;
@@ -74,11 +85,18 @@ let make ?(set_opts=fun _ -> ()) () : t =
 let delete = Curl.cleanup
 
 (* set options *)
-let _apply_config (self:t) (config:Config.t) : unit =
+let _apply_config (self : t) (config : Config.t) : unit =
   let {
-    Config.verbose; max_redirects; follow_location; authmethod;
-    username; password; user_agent
-  } = config in
+    Config.verbose;
+    max_redirects;
+    follow_location;
+    authmethod;
+    username;
+    password;
+    user_agent;
+  } =
+    config
+  in
   Curl.set_verbose self verbose;
   Curl.set_maxredirs self max_redirects;
   Curl.set_followlocation self follow_location;
@@ -88,10 +106,8 @@ let _apply_config (self:t) (config:Config.t) : unit =
   opt_iter password ~f:(Curl.set_password self);
   ()
 
-let _set_headers (self:t) (headers: _ list) : unit =
-  let headers =
-    List.map (fun (k,v) -> k ^ ": " ^ v) headers
-  in
+let _set_headers (self : t) (headers : _ list) : unit =
+  let headers = List.map (fun (k, v) -> k ^ ": " ^ v) headers in
   Curl.set_httpheader self headers;
   ()
 
@@ -111,7 +127,7 @@ type response_info = {
 }
 
 let pp_response_info out r =
-  let {ri_response_time; ri_redirect_count} = r in
+  let { ri_response_time; ri_redirect_count } = r in
   Format.fprintf out "{@[response_time=%.3fs;@ redirect_count=%d@]}"
     ri_response_time ri_redirect_count
 
@@ -125,17 +141,13 @@ type response = {
 }
 
 let pp_response out r =
-  let pp_header out (s1,s2) =
-    Format.fprintf out "@[<2>%s:@ %s@]" s1 s2
-  in
+  let pp_header out (s1, s2) = Format.fprintf out "@[<2>%s:@ %s@]" s1 s2 in
   let pp_headers out l =
     Format.fprintf out "@[<v>%a@]" (Format.pp_print_list pp_header) l
   in
-  let {code; body; headers; info; } = r in
+  let { code; body; headers; info } = r in
   Format.fprintf out "{@[code=%d;@ headers=@[%a@];@ info=%a;@ body=@[%a@]@]}"
-    code pp_headers headers pp_response_info info
-    Format.pp_print_text body
-
+    code pp_headers headers pp_response_info info Format.pp_print_text body
 
 let string_of_response s = Format.asprintf "%a" pp_response s
 
@@ -165,9 +177,10 @@ let pp_meth out m = Format.pp_print_string out (string_of_meth m)
 
 module type IO = sig
   type 'a t
+
   val return : 'a -> 'a t
-  val (>>=) : 'a t -> ('a -> 'b t) -> 'b t
-  val (>|=) : 'a t -> ('a -> 'b) -> 'b t
+  val ( >>= ) : 'a t -> ('a -> 'b t) -> 'b t
+  val ( >|= ) : 'a t -> ('a -> 'b) -> 'b t
   val fail : exn -> 'a t
   val perform : Curl.t -> Curl.curlCode t
 end
@@ -180,8 +193,8 @@ module type S = sig
     ?client:t ->
     ?config:Config.t ->
     ?range:string ->
-    ?content:[`String of string | `Write of (bytes -> int -> int)] ->
-    ?headers:(string*string) list ->
+    ?content:[ `String of string | `Write of bytes -> int -> int ] ->
+    ?headers:(string * string) list ->
     url:string ->
     meth:meth ->
     unit ->
@@ -211,7 +224,7 @@ module type S = sig
     ?client:t ->
     ?config:Config.t ->
     ?range:string ->
-    ?headers:(string*string) list ->
+    ?headers:(string * string) list ->
     url:string ->
     unit ->
     (response, Curl.curlCode * string) result io
@@ -223,9 +236,9 @@ module type S = sig
     ?tries:int ->
     ?client:t ->
     ?config:Config.t ->
-    ?headers:(string*string) list ->
+    ?headers:(string * string) list ->
     url:string ->
-    content:[`String of string | `Write of (bytes -> int -> int)] ->
+    content:[ `String of string | `Write of bytes -> int -> int ] ->
     unit ->
     (response, Curl.curlCode * string) result io
   (** Shortcut for [http ~meth:PUT]
@@ -236,8 +249,8 @@ module type S = sig
     ?tries:int ->
     ?client:t ->
     ?config:Config.t ->
-    ?headers:(string*string) list ->
-    ?content:[`String of string | `Write of (bytes -> int -> int)] ->
+    ?headers:(string * string) list ->
+    ?content:[ `String of string | `Write of bytes -> int -> int ] ->
     params:Curl.curlHTTPPost list ->
     url:string ->
     unit ->
@@ -249,33 +262,34 @@ end
 
 exception Parse_error of Curl.curlCode * string
 
-let mk_res (self:t) headers body : (response,_) result =
+let mk_res (self : t) headers body : (response, _) result =
   let split_colon s =
     match String.index s ':' with
     | exception Not_found ->
-      raise (Parse_error (Curl.CURLE_CONV_FAILED, "header line without a ':': " ^ s))
+      raise
+        (Parse_error (Curl.CURLE_CONV_FAILED, "header line without a ':': " ^ s))
     | i ->
-      String.sub s 0 i,
-      String.trim (String.sub s (i+1) (String.length s-i-1))
+      ( String.sub s 0 i,
+        String.trim (String.sub s (i + 1) (String.length s - i - 1)) )
   in
   try
     let code = Curl.get_httpcode self in
     let headers =
       match headers with
       | [] -> []
-      | _ :: tl -> List.map split_colon tl (* first one is "http1.1 NNN <descr>" *)
+      | _ :: tl ->
+        List.map split_colon tl (* first one is "http1.1 NNN <descr>" *)
     in
-    let info = {
-      ri_redirect_count=Curl.get_redirectcount self;
-      ri_response_time=Curl.get_totaltime self;
-    } in
-    Ok {headers; code; body; info}
-  with Parse_error (e, msg) ->
-    Error (e, Curl.strerror e ^ ": " ^ msg)
+    let info =
+      {
+        ri_redirect_count = Curl.get_redirectcount self;
+        ri_response_time = Curl.get_totaltime self;
+      }
+    in
+    Ok { headers; code; body; info }
+  with Parse_error (e, msg) -> Error (e, Curl.strerror e ^ ": " ^ msg)
 
-module Make(IO : IO)
-  : S with type 'a io = 'a IO.t
-= struct
+module Make (IO : IO) : S with type 'a io = 'a IO.t = struct
   open IO
 
   type 'a io = 'a IO.t
@@ -284,100 +298,92 @@ module Make(IO : IO)
     match content with
     | `String s ->
       let n = ref 0 in
-      (fun i ->
-         let len = min i (String.length s - !n) in
-         let r = String.sub s !n len in
-         n := !n + len;
-         r)
+      fun i ->
+        let len = min i (String.length s - !n) in
+        let r = String.sub s !n len in
+        n := !n + len;
+        r
     | `Write f ->
       let buf = Bytes.create 1024 in
-      (fun i ->
-         let len = min i (Bytes.length buf) in
-         let n = f buf len in
-         Bytes.sub_string buf i n)
+      fun i ->
+        let len = min i (Bytes.length buf) in
+        let n = f buf len in
+        Bytes.sub_string buf i n
 
   let content_size_ = function
     | `String s -> Some (String.length s)
     | `Write _ -> None
 
-  let http
-      ?(tries=1) ?client ?(config=Config.default) ?range ?content ?(headers=[]) ~url ~meth ()
-    : _ result io =
+  let http ?(tries = 1) ?client ?(config = Config.default) ?range ?content
+      ?(headers = []) ~url ~meth () : _ result io =
     let headers = ref headers in
-    let do_cleanup, self = match client with
-      | None -> true, make()
-      | Some c ->
-        false, c
+    let do_cleanup, self =
+      match client with
+      | None -> true, make ()
+      | Some c -> false, c
     in
     _apply_config self config;
     opt_iter range ~f:(fun s -> Curl.set_range self s);
 
     (* TODO: ability to make content a stream with a `read` function *)
-    opt_iter content
-      ~f:(fun content ->
+    opt_iter content ~f:(fun content ->
         Curl.set_readfunction self (content_read_fun_ content);
         (* also set size if known *)
         match content_size_ content, meth with
         | None, _ ->
-            headers := ("expect", "") :: ("transfer-encoding", "chunked") :: !headers
-        | Some size , POST _ ->
-            Curl.set_postfieldsize self size;
-        | Some size, _ ->
-            Curl.set_infilesize self size
-        );
+          headers :=
+            ("expect", "") :: ("transfer-encoding", "chunked") :: !headers
+        | Some size, POST _ -> Curl.set_postfieldsize self size
+        | Some size, _ -> Curl.set_infilesize self size);
 
     (* local state *)
-    let tries = max tries 1 in (* at least one attempt *)
+    let tries = max tries 1 in
+    (* at least one attempt *)
     let body = Buffer.create 64 in
     let resp_headers = ref [] in
-    let resp_headers_done = ref false in (* once we get "\r\n" header line *)
+    let resp_headers_done = ref false in
+    (* once we get "\r\n" header line *)
     Curl.set_url self url;
-    begin match meth with
-      | POST [] when (content <> None) ->
-        Curl.set_post self true
-      | POST l ->
-          Curl.set_httppost self l;
-      | GET -> Curl.set_httpget self true;
-      | PUT ->
-          Curl.set_customrequest self "PUT";
-          Curl.set_upload self true;
-      | DELETE -> Curl.set_customrequest self "DELETE";
-      | HEAD -> Curl.set_customrequest self "HEAD"
-      | CONNECT -> Curl.set_customrequest self "CONNECT"
-      | OPTIONS -> Curl.set_customrequest self "OPTIONS"
-      | TRACE -> Curl.set_customrequest self "TRACE"
-      | PATCH -> Curl.set_customrequest self "PATCH"
-    end;
+    (match meth with
+    | POST [] when content <> None -> Curl.set_post self true
+    | POST l -> Curl.set_httppost self l
+    | GET -> Curl.set_httpget self true
+    | PUT ->
+      Curl.set_customrequest self "PUT";
+      Curl.set_upload self true
+    | DELETE -> Curl.set_customrequest self "DELETE"
+    | HEAD -> Curl.set_customrequest self "HEAD"
+    | CONNECT -> Curl.set_customrequest self "CONNECT"
+    | OPTIONS -> Curl.set_customrequest self "OPTIONS"
+    | TRACE -> Curl.set_customrequest self "TRACE"
+    | PATCH -> Curl.set_customrequest self "PATCH");
 
     _set_headers self !headers;
-    Curl.set_headerfunction self
-      (fun s0 ->
-         let s = String.trim s0 in
-         (* Printf.printf "got header %S\n%!" s0; *)
-         if s0 = "\r\n" then (
-           resp_headers_done := true;
-         ) else (
-           (* redirection: drop previous headers *)
-           if !resp_headers_done then (
-             resp_headers_done := false;
-             resp_headers := [];
-           );
+    Curl.set_headerfunction self (fun s0 ->
+        let s = String.trim s0 in
+        (* Printf.printf "got header %S\n%!" s0; *)
+        if s0 = "\r\n" then
+          resp_headers_done := true
+        else (
+          (* redirection: drop previous headers *)
+          if !resp_headers_done then (
+            resp_headers_done := false;
+            resp_headers := []
+          );
 
-           resp_headers := s :: !resp_headers;
-         );
-         String.length s0);
-    Curl.set_writefunction self
-      (fun s ->
-         Buffer.add_string body s;
-         String.length s);
+          resp_headers := s :: !resp_headers
+        );
+        String.length s0);
+    Curl.set_writefunction self (fun s ->
+        Buffer.add_string body s;
+        String.length s);
     let rec loop i =
       IO.perform self >>= function
       | Curl.CURLE_OK ->
         let r = mk_res self (List.rev !resp_headers) (Buffer.contents body) in
         if do_cleanup then Curl.cleanup self;
         return r
-      | Curl.CURLE_AGAIN when i > 1 ->
-        loop (i-1) (* try again *)
+      | Curl.CURLE_AGAIN when i > 1 -> loop (i - 1) (* try again *)
       | c ->
         if do_cleanup then Curl.cleanup self;
         return (Error (c, Curl.strerror c))
@@ -385,11 +391,12 @@ module Make(IO : IO)
     loop tries
 
   let get ?tries ?client ?config ?range ?headers ~url () : _ result io =
-    http ?tries ?client ?config ?range ?headers  ~url ~meth:GET ()
+    http ?tries ?client ?config ?range ?headers ~url ~meth:GET ()
 
-  let post ?tries ?client ?config ?headers ?content ~params ~url () : _ result io =
+  let post ?tries ?client ?config ?headers ?content ~params ~url () :
+      _ result io =
     http ?tries ?client ?config ?headers ?content ~url ~meth:(POST params) ()
 
   let put ?tries ?client ?config ?headers ~url ~content () : _ result io =
-    http ?tries ?client ?config ?headers  ~url ~content ~meth:PUT ()
+    http ?tries ?client ?config ?headers ~url ~content ~meth:PUT ()
 end
diff --git a/src/core/Ezcurl_core.mli b/src/core/Ezcurl_core.mli
index bf93a61..b11b4e3 100644
--- a/src/core/Ezcurl_core.mli
+++ b/src/core/Ezcurl_core.mli
@@ -1,9 +1,9 @@
-
 (** Core signatures and implementation *)
 
 (** Configuration for the client. *)
 module Config : sig
   type t
+
   val default : t
   val verbose : bool -> t -> t
   val authmethod : Curl.curlAuth list -> t -> t
@@ -11,7 +11,6 @@ module Config : sig
   val follow_location : bool -> t -> t
   val username : string -> t -> t
   val password : string -> t -> t
-
   val pp : Format.formatter -> t -> unit
   val to_string : t -> string
 end
@@ -19,30 +18,26 @@ end
 type t = Curl.t
 (** A client, i.e. a cURL instance. *)
 
-val make :
-  ?set_opts:(t -> unit) ->
-  unit -> t
-  (** Create a new client.
+val make : ?set_opts:(t -> unit) -> unit -> t
+(** Create a new client.
    @param set_opts called before returning the client, to set options *)
 
 val delete : t -> unit
 (** Delete the client. It cannot be used anymore. *)
 
-val with_client :
-  ?set_opts:(t -> unit) ->
-  (t -> 'a) -> 'a
+val with_client : ?set_opts:(t -> unit) -> (t -> 'a) -> 'a
 (** Make a temporary client, call the function with it, then cleanup. *)
 
 (* TODO: duphandle is deprecated, how do we iterate on options?
-val copy : t -> t
-   *)
+   val copy : t -> t
+*)
 
 type response_info = {
   ri_response_time: float;
-  (** Total time (in seconds) for the request/response pair.
+      (** Total time (in seconds) for the request/response pair.
    See {!Curl.get_totaltime}. *)
   ri_redirect_count: int;
-  (** Number of redirects cURL followed.
+      (** Number of redirects cURL followed.
    See {!Curl.get_redirectcount}. *)
 }
 (** Metadata about a response from the server. *)
@@ -52,13 +47,10 @@ val string_of_response_info : response_info -> string
 
 type response = {
   code: int;
-  (** Response code. See https://developer.mozilla.org/en-US/docs/Web/HTTP/Status *)
-  headers: (string * string) list;
-  (** Response headers *)
-  body: string;
-  (** Response body, or [""] *)
-  info: response_info;
-  (** Information about the response *)
+      (** Response code. See https://developer.mozilla.org/en-US/docs/Web/HTTP/Status *)
+  headers: (string * string) list;  (** Response headers *)
+  body: string;  (** Response body, or [""] *)
+  info: response_info;  (** Information about the response *)
 }
 (** Response for a given request. *)
 
@@ -84,9 +76,10 @@ val string_of_meth : meth -> string
 (** {2 Underlying IO Monad} *)
 module type IO = sig
   type 'a t
+
   val return : 'a -> 'a t
-  val (>>=) : 'a t -> ('a -> 'b t) -> 'b t
-  val (>|=) : 'a t -> ('a -> 'b) -> 'b t
+  val ( >>= ) : 'a t -> ('a -> 'b t) -> 'b t
+  val ( >|= ) : 'a t -> ('a -> 'b) -> 'b t
   val fail : exn -> 'a t
   val perform : Curl.t -> Curl.curlCode t
 end
@@ -100,8 +93,8 @@ module type S = sig
     ?client:t ->
     ?config:Config.t ->
     ?range:string ->
-    ?content:[`String of string | `Write of (bytes -> int -> int)] ->
-    ?headers:(string*string) list ->
+    ?content:[ `String of string | `Write of bytes -> int -> int ] ->
+    ?headers:(string * string) list ->
     url:string ->
     meth:meth ->
     unit ->
@@ -131,7 +124,7 @@ module type S = sig
     ?client:t ->
     ?config:Config.t ->
     ?range:string ->
-    ?headers:(string*string) list ->
+    ?headers:(string * string) list ->
     url:string ->
     unit ->
     (response, Curl.curlCode * string) result io
@@ -143,9 +136,9 @@ module type S = sig
     ?tries:int ->
     ?client:t ->
     ?config:Config.t ->
-    ?headers:(string*string) list ->
+    ?headers:(string * string) list ->
     url:string ->
-    content:[`String of string | `Write of (bytes -> int -> int)] ->
+    content:[ `String of string | `Write of bytes -> int -> int ] ->
     unit ->
     (response, Curl.curlCode * string) result io
   (** Shortcut for [http ~meth:PUT]
@@ -156,8 +149,8 @@ module type S = sig
     ?tries:int ->
     ?client:t ->
     ?config:Config.t ->
-    ?headers:(string*string) list ->
-    ?content:[`String of string | `Write of (bytes -> int -> int)] ->
+    ?headers:(string * string) list ->
+    ?content:[ `String of string | `Write of bytes -> int -> int ] ->
     params:Curl.curlHTTPPost list ->
     url:string ->
     unit ->
@@ -167,4 +160,4 @@ module type S = sig
   *)
 end
 
-module Make(IO : IO) : S with type 'a io = 'a IO.t
+module Make (IO : IO) : S with type 'a io = 'a IO.t
diff --git a/src/lwt/Ezcurl_lwt.ml b/src/lwt/Ezcurl_lwt.ml
index f5aeb4c..b21c60e 100644
--- a/src/lwt/Ezcurl_lwt.ml
+++ b/src/lwt/Ezcurl_lwt.ml
@@ -1,7 +1,7 @@
-
 include Ezcurl_core
 
-include Make(struct
-    include Lwt
-    let perform = Curl_lwt.perform
+include Make (struct
+  include Lwt
+
+  let perform = Curl_lwt.perform
 end)
diff --git a/src/sync/Ezcurl.ml b/src/sync/Ezcurl.ml
index 1ac1f8a..5baca81 100644
--- a/src/sync/Ezcurl.ml
+++ b/src/sync/Ezcurl.ml
@@ -1,16 +1,19 @@
-
 (** {1 Synchronous API} *)
 
 include Ezcurl_core
 
-include Ezcurl_core.Make(struct
-    type 'a t = 'a
-    let return x = x
-    let (>>=) x f = f x
-    let (>|=) x f = f x
-    let fail e = raise e
-    let perform c =
-      try Curl.perform c; Curl.CURLE_OK
-      with Curl.CurlException (c, _, _) -> c
-  end)
+include Ezcurl_core.Make (struct
+  type 'a t = 'a
+
+  let return x = x
+  let ( >>= ) x f = f x
+  let ( >|= ) x f = f x
+  let fail e = raise e
+
+  let perform c =
+    try
+      Curl.perform c;
+      Curl.CURLE_OK
+    with Curl.CurlException (c, _, _) -> c
+end)
 
diff --git a/test/basic_test.ml b/test/basic_test.ml
index d0f8867..2a060af 100644
--- a/test/basic_test.ml
+++ b/test/basic_test.ml
@@ -1,6 +1,10 @@
 let () =
-  match Ezcurl.get ~url:"https://archive.softwareheritage.org/api/1/content/sha1_git:7bdf38d4468c114206c9b6ebd9cf1176e085d346/" () with
+  match
+    Ezcurl.get
+      ~url:
+        "https://archive.softwareheritage.org/api/1/content/sha1_git:7bdf38d4468c114206c9b6ebd9cf1176e085d346/"
+      ()
+  with
   | Error (code, msg) ->
     Format.eprintf "curl error: code `%s` (%s)@." (Curl.strerror code) msg
-  | Ok _response ->
-    Format.printf "OK@."
+  | Ok _response -> Format.printf "OK@."