commit b06a92c7de5fe5a5045ac98087a80b6834fca443
Author: pena <pena@kumikode.org>
Date:   Thu Jan 4 16:59:51 2024 +0100

    first commit

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..e35d885
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+_build
diff --git a/.ocamlformat b/.ocamlformat
new file mode 100644
index 0000000..1701629
--- /dev/null
+++ b/.ocamlformat
@@ -0,0 +1,43 @@
+version=0.28.1
+assignment-operator=end-line
+break-cases=fit
+break-fun-decl=wrap
+break-fun-sig=wrap
+break-infix=wrap
+break-infix-before-func=false
+break-separators=before
+break-sequences=true
+cases-exp-indent=2
+cases-matching-exp-indent=normal
+doc-comments=before
+doc-comments-padding=2
+doc-comments-tag-only=default
+dock-collection-brackets=false
+exp-grouping=preserve
+field-space=loose
+if-then-else=compact
+indicate-multiline-delimiters=space
+indicate-nested-or-patterns=unsafe-no
+infix-precedence=indent
+leading-nested-match-parens=false
+let-and=sparse
+let-binding-spacing=compact
+let-module=compact
+margin=80
+max-indent=2
+module-item-spacing=sparse
+ocaml-version=4.14.0
+ocp-indent-compat=false
+parens-ite=false
+parens-tuple=always
+parse-docstrings=true
+sequence-blank-line=preserve-one
+sequence-style=terminator
+single-case=compact
+space-around-arrays=true
+space-around-lists=true
+space-around-records=true
+space-around-variants=true
+type-decl=sparse
+wrap-comments=false
+wrap-fun-args=true
diff --git a/CHANGES.md b/CHANGES.md
new file mode 100644
index 0000000..d9cd2e7
--- /dev/null
+++ b/CHANGES.md
@@ -0,0 +1 @@
+## unreleased
diff --git a/LICENSE.md b/LICENSE.md
new file mode 100644
index 0000000..4ef32f0
--- /dev/null
+++ b/LICENSE.md
@@ -0,0 +1,651 @@
+GNU Affero General Public License
+=================================
+
+_Version 3, 19 November 2007_
+_Copyright © 2007 Free Software Foundation, Inc. &lt;<http://fsf.org/>&gt;_
+
+Everyone is permitted to copy and distribute verbatim copies
+of this license document, but changing it is not allowed.
+
+## Preamble
+
+The GNU Affero General Public License is a free, copyleft license for
+software and other kinds of works, specifically designed to ensure
+cooperation with the community in the case of network server software.
+
+The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works.  By contrast,
+our General Public Licenses are intended to guarantee your freedom to
+share and change all versions of a program--to make sure it remains free
+software for all its users.
+
+When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
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+
+Developers that use our General Public Licenses protect your rights
+with two steps: **(1)** assert copyright on the software, and **(2)** offer
+you this License which gives you legal permission to copy, distribute
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+A secondary benefit of defending all users' freedom is that
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+The precise terms and conditions for copying, distribution and
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+A patent license is “discriminatory” if it does not include within
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+or that patent license was granted, prior to 28 March 2007.
+
+Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+### 12. No Surrender of Others' Freedom
+
+If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License.  If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under this
+License and any other pertinent obligations, then as a consequence you may
+not convey it at all.  For example, if you agree to terms that obligate you
+to collect a royalty for further conveying from those to whom you convey
+the Program, the only way you could satisfy both those terms and this
+License would be to refrain entirely from conveying the Program.
+
+### 13. Remote Network Interaction; Use with the GNU General Public License
+
+Notwithstanding any other provision of this License, if you modify the
+Program, your modified version must prominently offer all users
+interacting with it remotely through a computer network (if your version
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+shall include the Corresponding Source for any work covered by version 3
+of the GNU General Public License that is incorporated pursuant to the
+following paragraph.
+
+Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
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+License will continue to apply to the part which is the covered work,
+but the work with which it is combined will remain governed by version
+3 of the GNU General Public License.
+
+### 14. Revised Versions of this License
+
+The Free Software Foundation may publish revised and/or new versions of
+the GNU Affero General Public License from time to time.  Such new versions
+will be similar in spirit to the present version, but may differ in detail to
+address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the
+Program specifies that a certain numbered version of the GNU Affero General
+Public License “or any later version” applies to it, you have the
+option of following the terms and conditions either of that numbered
+version or of any later version published by the Free Software
+Foundation.  If the Program does not specify a version number of the
+GNU Affero General Public License, you may choose any version ever published
+by the Free Software Foundation.
+
+If the Program specifies that a proxy can decide which future
+versions of the GNU Affero General Public License can be used, that proxy's
+public statement of acceptance of a version permanently authorizes you
+to choose that version for the Program.
+
+Later license versions may give you additional or different
+permissions.  However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+### 15. Disclaimer of Warranty
+
+THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM “AS IS” WITHOUT WARRANTY
+OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
+THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+PURPOSE.  THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM
+IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
+ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+### 16. Limitation of Liability
+
+IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+### 17. Interpretation of Sections 15 and 16
+
+If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+_END OF TERMS AND CONDITIONS_
+
+## How to Apply These Terms to Your New Programs
+
+If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the “copyright” line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Affero General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Affero General Public License for more details.
+
+    You should have received a copy of the GNU Affero General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+If your software can interact with users remotely through a computer
+network, you should also make sure that it provides a way for users to
+get its source.  For example, if your program is a web application, its
+interface could display a “Source” link that leads users to an archive
+of the code.  There are many ways you could offer source, and different
+solutions will be better for different programs; see section 13 for the
+specific requirements.
+
+You should also get your employer (if you work as a programmer) or school,
+if any, to sign a “copyright disclaimer” for the program, if necessary.
+For more information on this, and how to apply and follow the GNU AGPL, see
+&lt;<http://www.gnu.org/licenses/>&gt;.
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..e529b93
--- /dev/null
+++ b/README.md
@@ -0,0 +1,30 @@
+# Drame
+
+[Drame] is an [OCaml] web framework.
+
+## Installation
+
+`drame` can be installed with [opam]:
+
+```sh
+opam install drame
+```
+
+If you don't have `opam`, you can install it following the [how to install opam] guide.
+
+If you can't or don't want to use `opam`, consult the [opam file] for build instructions.
+
+## About
+
+- [LICENSE]
+- [CHANGELOG]
+
+[CHANGELOG]: ./CHANGES.md
+[example]: ./example
+[LICENSE]: ./LICENSE.md
+[opam file]: ./drame.opam
+
+[how to install opam]: https://opam.ocaml.org/doc/Install.html
+[OCaml]: https://ocaml.org
+[opam]: https://opam.ocaml.org
+[drame]: https://forge.kumikode.org/kumikode/drame
diff --git a/drame.opam b/drame.opam
new file mode 100644
index 0000000..7120e80
--- /dev/null
+++ b/drame.opam
@@ -0,0 +1,42 @@
+# This file is generated by dune, edit dune-project instead
+opam-version: "2.0"
+synopsis: "OCaml web framework"
+description: "Drame is an OCaml web framework."
+maintainer: ["pena <pena@kumikode.org>"]
+authors: ["pena <pena@kumikode.org>"]
+license: "AGPL-3.0-or-later"
+tags: ["drame" "TODO" "TODO" "TODO" "TODO"]
+homepage: "https://forge.kumikode.org/kumikode/drame"
+bug-reports: "https://forge.kumikode.org/kumikode/drame/issues"
+depends: [
+  "dune" {>= "3.0"}
+  "directories"
+  "h2"
+  "htmlit"
+  "httpcats"
+  "js_of_ocaml-compiler"
+  "miou"
+  "prelude"
+  "ptime"
+  "scfg"
+  "tyxml"
+  "uri"
+  "uuidm"
+  "ocaml" {>= "5.0.0"}
+  "odoc" {with-doc}
+]
+build: [
+  ["dune" "subst"] {dev}
+  [
+    "dune"
+    "build"
+    "-p"
+    name
+    "-j"
+    jobs
+    "@install"
+    "@runtest" {with-test}
+    "@doc" {with-doc}
+  ]
+]
+dev-repo: "git+https://forge.kumikode.org/kumikode/drame.git"
diff --git a/dune-project b/dune-project
new file mode 100644
index 0000000..3504c24
--- /dev/null
+++ b/dune-project
@@ -0,0 +1,42 @@
+(lang dune 3.0)
+
+(implicit_transitive_deps false)
+
+(name drame)
+
+(license AGPL-3.0-or-later)
+
+(authors "pena <pena@kumikode.org>")
+
+(maintainers "pena <pena@kumikode.org>")
+
+(source
+ (uri git+https://forge.kumikode.org/kumikode/drame.git))
+
+(homepage https://forge.kumikode.org/kumikode/drame)
+
+(bug_reports https://forge.kumikode.org/kumikode/drame/issues)
+
+(generate_opam_files true)
+
+(package
+ (name drame)
+ (synopsis "OCaml web framework")
+ (description "Drame is an OCaml web framework.")
+ (tags
+  (drame TODO TODO TODO TODO))
+ (depends
+  directories
+  h2
+  htmlit
+  httpcats
+  js_of_ocaml-compiler
+  miou
+  prelude
+  ptime
+  scfg
+  tyxml
+  uri
+  uuidm
+  (ocaml
+   (>= 5.0.0))))
diff --git a/example/dune b/example/dune
new file mode 100644
index 0000000..a342d72
--- /dev/null
+++ b/example/dune
@@ -0,0 +1,6 @@
+(executable
+ (name main)
+ (modules main)
+ (flags
+  (:standard -open Prelude))
+ (libraries drame fmt prelude scfg))
diff --git a/example/main.ml b/example/main.ml
new file mode 100644
index 0000000..47a6399
--- /dev/null
+++ b/example/main.ml
@@ -0,0 +1,80 @@
+open Drame
+open Tyxml
+open Tyxml.Html
+
+module App_id = struct
+  let qualifier = "org"
+
+  let organization = "drame"
+
+  let application = "drame"
+end
+
+module Server = Server.Make (App_id)
+
+let template_html (_request : Request.t) ~title ~body =
+  let styles =
+    List.map
+      (fun s -> link ~rel:[ `Stylesheet ] ~href:(Fmt.str "/assets/css/%s" s) ())
+      [ "style.css" ]
+  in
+  let head = head (Html.title title) styles in
+  let body = Html.body [ main [ h1 [ title ]; body ] ] in
+  let a = [ a_lang "en" ] in
+  let tyxml_doc = html ~a head body in
+  Html_doc.of_tyxml tyxml_doc
+
+let hello =
+  let body = txt "How are you doing?" in
+  fun ~name ->
+    let title = Fmt.kstr txt "Hello %s!" name in
+    fun request ->
+      let doc = template_html request ~title ~body in
+      let content = Content.Html doc in
+      Ok content
+
+let hello_q request =
+  let name = Request.query request "name" in
+  let name = Option.value name ~default:"World" in
+  let msg = Fmt.kstr txt "Hello %s!" name in
+  let doc = template_html request ~title:msg ~body:msg in
+  let content = Content.Html doc in
+  Ok content
+
+let config =
+  let title = txt "Configuration" in
+  let body = Fmt.kstr txt "%a" Scfg.Pp.config Server.config in
+  fun request ->
+    let doc = template_html request ~title ~body in
+    let content = Content.Html doc in
+    Ok content
+
+let not_found =
+  let title = txt "404 Not Found" in
+  let body = txt "Ooops :S" in
+  fun request ->
+    let content = template_html request ~title ~body in
+    Error (Status.Not_found, content)
+
+let style =
+  let sheet =
+    {css|body {
+  color: #ebb2bf;
+  background-color: #0f1312;
+}|css}
+  in
+  let content = Content.Unsafe { content = sheet; mimetype = Text_css } in
+  fun _request -> Ok content
+
+let handler route =
+  Fmt.pr "[request] %a@\n" Route.pp route;
+  Fmt.flush Fmt.stdout ();
+  match route with
+  | [||] -> hello ~name:"World"
+  | [| "assets"; "css"; "style.css" |] -> style
+  | [| "config" |] -> config
+  | [| "hello"; name |] -> hello ~name
+  | [| "helloq" |] -> hello_q
+  | _ -> not_found
+
+let () = Server.run ~handler
diff --git a/shell.nix b/shell.nix
new file mode 100644
index 0000000..92a5619
--- /dev/null
+++ b/shell.nix
@@ -0,0 +1,43 @@
+{ pkgs ? import (builtins.fetchTarball {
+    url = "https://github.com/NixOS/nixpkgs/archive/master.tar.gz";
+  }) {}
+}:
+
+let
+  ocamlPackages = pkgs.ocaml-ng.ocamlPackages_5_4.overrideScope (self: super: {
+    htmlit = ocamlPackages.buildTopkgPackage rec {
+      pname = "htmlit";
+      version = "0.2.0";
+
+      minimalOCamlVersion = "4.14.0";
+
+      src = pkgs.fetchzip {
+        url = "https://erratique.ch/software/htmlit/releases/htmlit-${version}.tbz";
+        hash = "sha256-vE6XY7INMCwQztZqKhJaxpNF0o5+NeutJM5XobshClE=";
+      };
+    };
+  });
+in
+
+pkgs.mkShell {
+  nativeBuildInputs = with ocamlPackages; [
+    dune_3
+    findlib
+    merlin
+    ocaml
+    ocamlformat
+    odoc
+  ];
+  buildInputs = with ocamlPackages; [
+    httpcats
+    js_of_ocaml-compiler
+    miou
+    ptime
+    htmlit
+    scfg
+    tyxml
+    uri
+    uuidm
+    directories
+  ];
+}
diff --git a/src/content.ml b/src/content.ml
new file mode 100644
index 0000000..3c372e7
--- /dev/null
+++ b/src/content.ml
@@ -0,0 +1,18 @@
+type t =
+  (*
+  | Css of string Css.css
+  *)
+  | Html of Html_doc.t
+  | JavaScript of Js_of_ocaml_compiler.Javascript.program
+  | Txt of string
+  | Unsafe of
+      { content : string
+      ; mimetype : Mimetype.t
+      }
+
+let to_mimetype = function
+  (* | Css _ -> Mimetype.Text_css *)
+  | Html _ -> Mimetype.Text_html
+  | JavaScript _ -> Mimetype.Text_javascript
+  | Txt _ -> Mimetype.Text_plain
+  | Unsafe { mimetype; _ } -> mimetype
diff --git a/src/content.mli b/src/content.mli
new file mode 100644
index 0000000..4d36cb1
--- /dev/null
+++ b/src/content.mli
@@ -0,0 +1,13 @@
+type t =
+  (*
+  | Css of string Css.css
+  *)
+  | Html of Html_doc.t
+  | JavaScript of Js_of_ocaml_compiler.Javascript.program
+  | Txt of string
+  | Unsafe of
+      { content : string
+      ; mimetype : Mimetype.t
+      }
+
+val to_mimetype : t -> Mimetype.t
diff --git a/src/cookie.ml b/src/cookie.ml
new file mode 100644
index 0000000..01784a8
--- /dev/null
+++ b/src/cookie.ml
@@ -0,0 +1,60 @@
+let pair_of_string s =
+  let ss = String.split_on_char '=' s in
+  match ss with [ a; b ] -> Some (String.trim a, String.trim b) | _ -> None
+
+let pairs_of_header header =
+  let ss = String.split_on_char ';' header in
+  List.filter_map pair_of_string ss
+
+let all_cookies request =
+  let headers = Request.headers request "Cookie" in
+  List.concat_map pairs_of_header headers
+
+let get ~decrypt:_ request id =
+  let path = Some "/" in
+  let secure = true in
+  let cookie_prefix =
+    if true then ""
+    else
+      match (path, secure) with
+      | Some "/", true -> "__Host-"
+      | _, true -> "__Secure-"
+      | _, _ -> ""
+  in
+  let name = Fmt.str "%s%s" cookie_prefix id in
+  let cookies = all_cookies request in
+  let v = List.find_opt (fun (name', _) -> String.equal name name') cookies in
+  Option.map snd v
+
+let to_set_cookie ~max_age ~path name value =
+  let max_age =
+    match max_age with
+    | None -> ""
+    | Some seconds -> Fmt.str "; Max-Age=%.0f" (floor seconds)
+  in
+
+  let path =
+    match path with None -> "" | Some path -> Fmt.str "; Path=%s" path
+  in
+
+  let secure = if true then "" else "; Secure" in
+  let http_only = "; HttpOnly" in
+  let same_site = "; SameSite=Lax" in
+
+  Fmt.str "%s=%s%s%s%s%s%s" name value max_age path secure http_only same_site
+
+let make_set_headers ~encrypt:(_ : bool) ~max_age ~key ~value =
+  let path = Some "/" in
+  let secure = true in
+  let cookie_prefix =
+    if true then ""
+    else
+      match (path, secure) with
+      | Some "/", true -> "__Host-"
+      | _, true -> "__Secure-"
+      | _, _ -> ""
+  in
+  let name = Fmt.str "%s%s" cookie_prefix key in
+
+  let set_cookie = to_set_cookie ~max_age ~path name value in
+  [ ("Set-Cookie", set_cookie) ]
diff --git a/src/cookie.mli b/src/cookie.mli
new file mode 100644
index 0000000..b3f162a
--- /dev/null
+++ b/src/cookie.mli
@@ -0,0 +1,8 @@
+val get : decrypt:bool -> Request.t -> string -> string option
+
+val make_set_headers :
+     encrypt:bool
+  -> max_age:float option
+  -> key:string
+  -> value:string
+  -> (string * string) list
diff --git a/src/dune b/src/dune
new file mode 100644
index 0000000..063c261
--- /dev/null
+++ b/src/dune
@@ -0,0 +1,41 @@
+(library
+ (public_name drame)
+ (modules
+  content
+  cookie
+  form
+  handler
+  html_doc
+  meth
+  mimetype
+  request
+  response
+  route
+  server
+  session
+  status
+  syntax)
+ (libraries
+  bigstringaf
+  bstr
+  directories
+  fmt
+  fpath
+  h1
+  h2
+  httpcats
+  (re_export js_of_ocaml-compiler)
+  miou
+  miou.unix
+  prelude
+  ptime
+  ptime.clock.os
+  (re_export scfg)
+  (re_export tyxml)
+  (re_export tyxml.functor)
+  htmlit
+  unix
+  uri
+  uuidm)
+ (flags
+  (:standard -open Prelude)))
diff --git a/src/form.ml b/src/form.ml
new file mode 100644
index 0000000..d9fc92f
--- /dev/null
+++ b/src/form.ml
@@ -0,0 +1,13 @@
+let form request =
+  match Request.header request "Content-Type" with
+  | None -> Error "missing content type"
+  | Some content_type -> (
+    match String.split_on_char ';' content_type with
+    | "application/x-www-form-urlencoded" :: _tl ->
+      let body = request.get_body () in
+      let query = Uri.query_of_encoded body in
+      let form =
+        List.map (fun (name, values) -> (name, String.concat "," values)) query
+      in
+      Ok (List.sort (Pair.compare String.compare String.compare) form)
+    | _content_type -> Error "wrong content type" )
diff --git a/src/form.mli b/src/form.mli
new file mode 100644
index 0000000..7555aa0
--- /dev/null
+++ b/src/form.mli
@@ -0,0 +1 @@
+val form : Request.t -> ((string * string) list, string) result
diff --git a/src/handler.ml b/src/handler.ml
new file mode 100644
index 0000000..9e2e974
--- /dev/null
+++ b/src/handler.ml
@@ -0,0 +1 @@
+type t = Route.t -> Request.t -> Response.t
diff --git a/src/handler.mli b/src/handler.mli
new file mode 100644
index 0000000..9e2e974
--- /dev/null
+++ b/src/handler.mli
@@ -0,0 +1 @@
+type t = Route.t -> Request.t -> Response.t
diff --git a/src/html_doc.ml b/src/html_doc.ml
new file mode 100644
index 0000000..3059671
--- /dev/null
+++ b/src/html_doc.ml
@@ -0,0 +1,9 @@
+type t = string
+
+let to_string = Fun.id
+
+let of_tyxml doc =
+  let indent = false in
+  Fmt.str "%a@\n" (Tyxml.Html.pp ~indent ()) doc
+
+let of_htmlit doc = Htmlit.El.to_string ~doctype:true doc
diff --git a/src/html_doc.mli b/src/html_doc.mli
new file mode 100644
index 0000000..1dc4a84
--- /dev/null
+++ b/src/html_doc.mli
@@ -0,0 +1,7 @@
+type t
+
+val to_string : t -> string
+
+val of_tyxml : Tyxml.Html.doc -> t
+
+val of_htmlit : Htmlit.El.html -> t
diff --git a/src/meth.ml b/src/meth.ml
new file mode 100644
index 0000000..b26d980
--- /dev/null
+++ b/src/meth.ml
@@ -0,0 +1,21 @@
+type t =
+  | Connect
+  | Delete
+  | Get
+  | Head
+  | Options
+  | Post
+  | Put
+  | Trace
+  | Other of string
+
+let of_httpcats = function
+  | `CONNECT -> Connect
+  | `DELETE -> Delete
+  | `GET -> Get
+  | `HEAD -> Head
+  | `OPTIONS -> Options
+  | `POST -> Post
+  | `PUT -> Put
+  | `TRACE -> Trace
+  | `Other s -> Other s
diff --git a/src/meth.mli b/src/meth.mli
new file mode 100644
index 0000000..50bb802
--- /dev/null
+++ b/src/meth.mli
@@ -0,0 +1,12 @@
+type t =
+  | Connect
+  | Delete
+  | Get
+  | Head
+  | Options
+  | Post
+  | Put
+  | Trace
+  | Other of string
+
+val of_httpcats : H2.Method.t -> t
diff --git a/src/mimetype.ml b/src/mimetype.ml
new file mode 100644
index 0000000..13ae549
--- /dev/null
+++ b/src/mimetype.ml
@@ -0,0 +1,71 @@
+type t =
+  | Audio_aac
+  | Audio_midi
+  | Audio_mp3
+  | Audio_wav
+  | Audio_weba
+  | Application_epub
+  | Application_json
+  | Application_jsonld
+  | Application_gz
+  | Application_tar
+  | Application_xml
+  | Application_atom_xml
+  | Application_zip
+  | Application_7z
+  | Image_bmp
+  | Image_jpeg
+  | Image_gif
+  | Image_ico
+  | Image_png
+  | Image_svg
+  | Image_webp
+  | Font_ttf
+  | Text_css
+  | Text_csv
+  | Text_html
+  | Text_javascript
+  | Text_plain
+  | Unsafe of string * bool
+  | Video_avi
+  | Video_mp4
+  | Video_webm
+
+let pp fmt mimetype =
+  Fmt.string fmt
+    ( match mimetype with
+    | Audio_aac -> "audio/aac"
+    | Audio_midi -> "audio/midi"
+    | Audio_mp3 -> "audio/mpeg"
+    | Audio_wav -> "audio/wav"
+    | Audio_weba -> "audio/webm"
+    | Application_epub -> "application/epub+zip"
+    | Application_json -> "application/json"
+    | Application_jsonld -> "application/ld+json"
+    | Application_gz -> "application/gzip"
+    | Application_tar -> "application/x-tar"
+    | Application_xml -> "application/xml"
+    | Application_atom_xml -> "application/atom+xml"
+    | Application_zip -> "application/zip"
+    | Application_7z -> "application/x-7z-compressed"
+    | Image_bmp -> "image/bmp"
+    | Image_jpeg -> "image/jpeg"
+    | Image_gif -> "image/gif"
+    | Image_ico -> "image/vnd.microsoft.icon"
+    | Image_png -> "image/png"
+    | Image_svg -> "image/svg+xml"
+    | Image_webp -> "image/webp"
+    | Font_ttf -> "font/ttf"
+    | Text_css -> "text/css;charset=utf-8"
+    | Text_csv -> "text/csv;charset=utf-8"
+    | Text_html -> "text/html;charset=utf-8"
+    | Text_javascript ->
+      (* setting a charset is invalid for JavaScript! *)
+      "text/javascript"
+    | Text_plain -> "text/plain;charset=utf-8"
+    | Unsafe (mimetype, _should_cache) -> mimetype
+    | Video_avi -> "video/x-msvideo"
+    | Video_mp4 -> "video/mp4"
+    | Video_webm -> "video/webm" )
+
+let to_string mimetype = Fmt.str "%a" pp mimetype
diff --git a/src/mimetype.mli b/src/mimetype.mli
new file mode 100644
index 0000000..47f928c
--- /dev/null
+++ b/src/mimetype.mli
@@ -0,0 +1,37 @@
+(* some common MIME types found on https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/MIME_types/Common_types *)
+type t =
+  | Audio_aac
+  | Audio_midi
+  | Audio_mp3
+  | Audio_wav
+  | Audio_weba
+  | Application_epub
+  | Application_json
+  | Application_jsonld
+  | Application_gz
+  | Application_tar
+  | Application_xml
+  | Application_atom_xml
+  | Application_zip
+  | Application_7z
+  | Image_bmp
+  | Image_jpeg
+  | Image_gif
+  | Image_ico
+  | Image_png
+  | Image_svg
+  | Image_webp
+  | Font_ttf
+  | Text_css
+  | Text_csv
+  | Text_html
+  | Text_javascript
+  | Text_plain
+  | Unsafe of string * bool (* mime-type / should be cached *)
+  | Video_avi
+  | Video_mp4
+  | Video_webm
+
+val pp : Format.formatter -> t -> unit
+
+val to_string : t -> string
diff --git a/src/request.ml b/src/request.ml
new file mode 100644
index 0000000..650b130
--- /dev/null
+++ b/src/request.ml
@@ -0,0 +1,119 @@
+type query = (string * string list) list
+
+type headers = (string * string) list
+
+type t =
+  { route : Route.t
+  ; meth : Meth.t
+  ; query : query
+  ; headers : headers
+  ; get_body : unit -> string
+  }
+
+let pp_comma fmt () = Fmt.char fmt ','
+
+let pp_comma_sep_string_list = Fmt.list ~sep:pp_comma Fmt.string
+
+let query_values_to_string query = Fmt.str "%a" pp_comma_sep_string_list query
+
+let query { query; _ } name : string option =
+  let query = List.assoc_opt name query in
+  Option.map query_values_to_string query
+
+let queries { query; _ } name : string list =
+  List.filter_map
+    (fun (name', values) ->
+      if String.equal name name' then
+        let values = query_values_to_string values in
+        Some values
+      else None )
+    query
+
+let all_queries { query; _ } : (string * string) list =
+  List.map
+    (fun (name, values) ->
+      let values = query_values_to_string values in
+      (name, values) )
+    query
+
+let header { headers; _ } name : string option =
+  let header =
+    List.find_opt (fun (name', _value) -> String.equal name name') headers
+  in
+  Option.map snd header
+
+let headers { headers; _ } name : string list =
+  List.filter_map
+    (fun (name', value) -> if String.equal name name' then Some value else None)
+    headers
+
+let all_headers { headers; _ } : (string * string) list = headers
+
+let request_from_httpaf ~scheme { H1.Request.meth; target; headers; _ } =
+  let headers = H2.Headers.of_list (H1.Headers.to_list headers) in
+  Httpcats.Server.{ meth; target; scheme; headers }
+
+let request_from_h2 { H2.Request.meth; target; scheme; headers } =
+  Httpcats.Server.{ meth; target; scheme; headers }
+
+let request_of_reqd ~scheme reqd =
+  match reqd with
+  | `V1 reqd ->
+    let request = H1.Reqd.request reqd in
+    request_from_httpaf ~scheme request
+  | `V2 reqd ->
+    let request = H2.Reqd.request reqd in
+    request_from_h2 request
+
+let get_body reqd =
+  let aux schedule close =
+    (* TODO implement a Bstr_buffer *)
+    let buf = Buffer.create 0x1000 in
+    let rec on_eof () = close ()
+    and on_read bs ~off ~len =
+      let s = Bstr.sub_string ~off ~len bs in
+      Buffer.add_string buf s;
+      schedule ~on_eof ~on_read
+    in
+    schedule ~on_eof ~on_read;
+    let body = Buffer.contents buf in
+    body
+  in
+  let aux' schedule close =
+    (* TODO implement a Bstr_buffer *)
+    let buf = Buffer.create 0x1000 in
+    let rec on_eof () = close ()
+    and on_read bs ~off ~len =
+      let s = Bigstringaf.substring ~off ~len bs in
+      Buffer.add_string buf s;
+      schedule ~on_eof ~on_read
+    in
+    schedule ~on_eof ~on_read;
+    let body = Buffer.contents buf in
+    body
+  in
+  match reqd with
+  | `V1 reqd ->
+    let body_reader = H1.Reqd.request_body reqd in
+    aux (H1.Body.Reader.schedule_read body_reader) (fun () ->
+      H1.Body.Reader.close body_reader )
+  | `V2 reqd ->
+    let body_reader = H2.Reqd.request_body reqd in
+    aux' (H2.Body.Reader.schedule_read body_reader) (fun () ->
+      H2.Body.Reader.close body_reader )
+
+let of_reqd reqd =
+  let { Httpcats.Server.target; meth; headers; _ } =
+    request_of_reqd ~scheme:"https" reqd
+  in
+  let target = Uri.of_string target in
+  let query =
+    match Uri.verbatim_query target with
+    | None -> []
+    | Some query -> Uri.query_of_encoded query
+  in
+  let route = Uri.path target |> Route.of_string in
+  let headers = H2.Headers.to_list headers in
+  let meth = Meth.of_httpcats meth in
+  let get_body () = get_body reqd in
+  { route; meth; query; headers; get_body }
diff --git a/src/request.mli b/src/request.mli
new file mode 100644
index 0000000..3e1826a
--- /dev/null
+++ b/src/request.mli
@@ -0,0 +1,31 @@
+type query
+
+type headers
+
+type t = private
+  { route : Route.t
+  ; meth : Meth.t
+  ; query : query
+  ; headers : headers
+  ; get_body : unit -> string
+  }
+
+(** Queries *)
+
+val query : t -> string -> string option
+
+val queries : t -> string -> string list
+
+val all_queries : t -> (string * string) list
+
+(** Headers *)
+
+val header : t -> string -> string option
+
+val headers : t -> string -> string list
+
+val all_headers : t -> (string * string) list
+
+(** Internal *)
+
+val of_reqd : Httpcats.Server.reqd -> t
diff --git a/src/response.ml b/src/response.ml
new file mode 100644
index 0000000..e6c1dbb
--- /dev/null
+++ b/src/response.ml
@@ -0,0 +1 @@
+type t = (Content.t, Status.error * Html_doc.t) Result.t
diff --git a/src/response.mli b/src/response.mli
new file mode 100644
index 0000000..e6c1dbb
--- /dev/null
+++ b/src/response.mli
@@ -0,0 +1 @@
+type t = (Content.t, Status.error * Html_doc.t) Result.t
diff --git a/src/route.ml b/src/route.ml
new file mode 100644
index 0000000..759de4a
--- /dev/null
+++ b/src/route.ml
@@ -0,0 +1,11 @@
+type t = string array
+
+let pp fmt route =
+  Fmt.pf fmt "/%a"
+    (Fmt.array ~sep:(fun fmt () -> Fmt.char fmt '/') Fmt.string)
+    route
+
+let of_string s =
+  let ss = String.split_on_char '/' s in
+  let ss = List.filter (fun s -> not (String.equal "" s)) ss in
+  Array.of_list ss
diff --git a/src/route.mli b/src/route.mli
new file mode 100644
index 0000000..8bd415d
--- /dev/null
+++ b/src/route.mli
@@ -0,0 +1,5 @@
+type t = string array
+
+val pp : Format.formatter -> t -> unit
+
+val of_string : string -> t
diff --git a/src/server.ml b/src/server.ml
new file mode 100644
index 0000000..13dbd82
--- /dev/null
+++ b/src/server.ml
@@ -0,0 +1,159 @@
+module Make (App_id : sig
+  val qualifier : string
+
+  val organization : string
+
+  val application : string
+end) =
+struct
+  module Project = struct
+    include Directories.Project_dirs (App_id)
+
+    let force_dir d name =
+      match d with
+      | None -> Fmt.failwith "can not compute %s directory path" name
+      | Some dir -> dir
+
+    let cache_dir = force_dir cache_dir "cache"
+
+    let config_dir = force_dir config_dir "config"
+
+    let data_dir = force_dir data_dir "data"
+
+    let data_local_dir = force_dir data_local_dir "data local"
+
+    let preference_dir = force_dir preference_dir "preference"
+
+    let runtime_dir = force_dir runtime_dir "runtime"
+
+    let state_dir = force_dir state_dir "state"
+  end
+
+  let config =
+    let filename = Fpath.(Project.config_dir / "config.scfg") in
+    match Scfg.Parse.from_file filename with
+    | Error (`Msg msg) -> Fmt.failwith "%s" msg
+    | Ok config -> config
+
+  open Scfg.Query
+
+  let port =
+    let directive = get_dir "port" config in
+    match directive with
+    | None -> Fmt.failwith "configuration file is missing a port directive"
+    | Some directive -> (
+      let param = get_param_int 0 directive in
+      match param with
+      | Error (`Msg msg) -> Fmt.failwith "%s" msg
+      | Ok port -> port )
+
+  let listen () =
+    let inet_addr = Unix.inet_addr_any in
+    let sockaddr = Unix.ADDR_INET (inet_addr, port) in
+    sockaddr
+
+  let stop = Httpcats.Server.stop ()
+
+  let prepare_content content =
+    let content_type = Content.to_mimetype content |> Mimetype.to_string in
+    let content =
+      match content with
+      (* | Content.Css sheet -> Fmt.str "%a@\n" Css.pp_string_css sheet *)
+      | Html doc -> Html_doc.to_string doc
+      | JavaScript program ->
+        let open Js_of_ocaml_compiler in
+        let accept_unnamed_var = true in
+        let buffer = Buffer.create 4096 in
+        let pp = Pretty_print.to_buffer buffer in
+        let _source_map : Source_map.info =
+          Js_output.program ~accept_unnamed_var pp program
+        in
+        (* setting a charset is invalid for JavaScript ! *)
+        Buffer.contents buffer
+      | Txt txt -> txt
+      | Unsafe { content; _ } -> content
+    in
+    let content_length = String.length content in
+    let headers =
+      [ ("content-type", content_type)
+      ; ("content-length", string_of_int content_length)
+      ]
+    in
+    (headers, content)
+
+  let status_of_response = function
+    | Ok _ -> `OK
+    | Error (status, _) -> Status.to_httpcats status
+
+  let status_headers_of_response = function
+    | Ok content -> begin
+      match Content.to_mimetype content with
+      | Audio_aac | Audio_midi | Audio_mp3 | Audio_wav | Audio_weba | Image_jpeg
+      | Image_png | Image_gif | Image_bmp | Image_ico | Image_svg | Image_webp
+      | Font_ttf | Text_css | Text_javascript
+      | Unsafe (_, true) ->
+        [ ("Cache-Control", "max-age=151200") ]
+      | Text_html | Text_plain
+      | Unsafe (_, false)
+      | Application_epub | Application_json | Application_jsonld
+      | Application_gz | Application_tar | Application_xml
+      | Application_atom_xml | Application_zip | Application_7z | Text_csv
+      | Video_avi | Video_mp4 | Video_webm ->
+        []
+    end
+    | Error
+        ( ( Status.See_other redirect
+          | Found redirect
+          | Moved_permanently redirect )
+        , _ ) ->
+      [ ("Location", redirect) ]
+    | Error _ -> []
+
+  let content_of_response = function
+    | Ok content -> content
+    | Error (_, content) -> Content.Html content
+
+  (* TODO :/ *)
+  let downgrade_status : Httpcats.Status.t -> H1.Status.t = function
+    | `Misdirected_request -> assert false
+    | `Code _ -> assert false
+    | #H1.Status.standard as t -> t
+
+  let respond reqd headers status content =
+    match reqd with
+    | `V1 reqd ->
+      let open H1 in
+      let headers = Headers.of_list headers in
+      let status = downgrade_status status in
+      let resp = Response.create ~headers status in
+      Reqd.respond_with_string reqd resp content
+    | `V2 reqd ->
+      let open H2 in
+      let headers = Headers.of_list headers in
+      let resp = Response.create ~headers status in
+      Reqd.respond_with_string reqd resp content
+
+  let mk_server ~(handler : Handler.t) =
+    let handler (_ : [ `Tcp of Miou_unix.file_descr | `Tls of _ ])
+      (reqd : Httpcats.Server.reqd) =
+      let ({ Request.route; _ } as request) = Request.of_reqd reqd in
+      let response = handler route request in
+      let status = status_of_response response in
+      let status_headers = status_headers_of_response response in
+      let content = content_of_response response in
+      let session = Session.load request in
+      let session_headers = Session.make_send_headers session in
+      let content_headers, content = prepare_content content in
+      let headers = session_headers @ content_headers @ status_headers in
+      respond reqd headers status content
+    in
+    let file_descr = listen () in
+    Httpcats.Server.clear ~stop ~handler file_descr;
+    ()
+
+  let () = Sys.set_signal Sys.sigpipe Sys.Signal_ignore
+
+  let run ~(handler : Handler.t) =
+    let server () = mk_server ~handler in
+    Miou_unix.run server
+end
diff --git a/src/server.mli b/src/server.mli
new file mode 100644
index 0000000..0c9d08f
--- /dev/null
+++ b/src/server.mli
@@ -0,0 +1,27 @@
+module Make (App_id : sig
+  val qualifier : string
+
+  val organization : string
+
+  val application : string
+end) : sig
+  module Project : sig
+    val cache_dir : Fpath.t
+
+    val config_dir : Fpath.t
+
+    val data_dir : Fpath.t
+
+    val data_local_dir : Fpath.t
+
+    val preference_dir : Fpath.t
+
+    val runtime_dir : Fpath.t
+
+    val state_dir : Fpath.t
+  end
+
+  val config : Scfg.Types.config
+
+  val run : handler:Handler.t -> unit
+end
diff --git a/src/session.ml b/src/session.ml
new file mode 100644
index 0000000..05ebd00
--- /dev/null
+++ b/src/session.ml
@@ -0,0 +1,151 @@
+let random_state = Random.State.make_self_init ()
+
+module Id = struct
+  type t = Uuidm.t
+
+  let create () =
+    (* TODO: use a CSPRNG *)
+    Uuidm.v4_gen random_state ()
+
+  let equal = Uuidm.equal
+
+  let hash (t : t) = Hashtbl.hash t
+
+  let of_string = Uuidm.of_string
+
+  let to_string = Uuidm.to_string ~upper:false
+
+  let pp = Uuidm.pp
+end
+
+type t =
+  { id : Id.t
+  ; mutable expires_at : Ptime.t
+  ; mutable payload : (string * string) list
+  }
+
+module Tbl : sig
+  val find : Id.t -> t option
+
+  val add : Id.t -> t -> unit
+
+  val remove : Id.t -> unit
+end = struct
+  include Hashtbl.Make (Id)
+
+  let tbl = create 512
+
+  let mutex = Mutex.create ()
+
+  let finally () = Mutex.unlock mutex
+
+  let find key =
+    Mutex.lock mutex;
+    Fun.protect ~finally (fun () -> find_opt tbl key)
+
+  let add key value =
+    Mutex.lock mutex;
+    Fun.protect ~finally (fun () -> replace tbl key value)
+
+  let remove key =
+    Mutex.lock mutex;
+    Fun.protect ~finally (fun () -> remove tbl key)
+end
+
+let now () = Ptime.v (Ptime_clock.now_d_ps ())
+
+let two_weeks =
+  match Ptime.Span.of_float_s (60. *. 60. *. 24. *. 7. *. 2.) with
+  | None -> assert false
+  | Some span -> span
+
+let one_week =
+  match Ptime.Span.of_float_s (60. *. 60. *. 24. *. 7.) with
+  | None -> assert false
+  | Some span -> span
+
+let create () =
+  let id = Id.create () in
+  let expires_at = Ptime.add_span (now ()) two_weeks in
+  let expires_at =
+    match expires_at with None -> assert false | Some expires_at -> expires_at
+  in
+  let payload = [] in
+  { id; expires_at; payload }
+
+let load request =
+  let now = now () in
+  let valid_session =
+    let session_id = Cookie.get ~decrypt:false request "drame.session" in
+    match session_id with
+    | None -> None
+    | Some session_id -> (
+      match Id.of_string session_id with
+      | None -> None
+      | Some session_id -> (
+        match Tbl.find session_id with
+        | None -> None
+        | Some { id; expires_at; _ } as session ->
+          let is_valid = Ptime.is_earlier now ~than:expires_at in
+          if is_valid then session
+          else begin
+            Tbl.remove id;
+            None
+          end ) )
+  in
+  match valid_session with
+  | None ->
+    let session = create () in
+    Tbl.add session.id session;
+    session
+  | Some ({ expires_at; _ } as session) ->
+    let renew_date =
+      match Ptime.sub_span expires_at one_week with
+      | None -> assert false
+      | Some span -> span
+    in
+    if Ptime.is_earlier now ~than:renew_date then session
+    else begin
+      let expires_at =
+        match Ptime.add_span now two_weeks with
+        | None -> assert false
+        | Some date -> date
+      in
+      session.expires_at <- expires_at;
+      session
+    end
+
+let get request key =
+  let { payload; _ } = load request in
+  List.assoc_opt key payload
+
+let set request key value =
+  let ({ payload; _ } as session) = load request in
+  let payload = List.remove_assoc key payload in
+  let payload = (key, value) :: payload in
+  session.payload <- payload
+
+let drop request key =
+  let ({ payload; _ } as session) = load request in
+  let payload = List.remove_assoc key payload in
+  session.payload <- payload
+
+let invalidate request =
+  let { id; _ } = load request in
+  Tbl.remove id
+
+let make_send_headers session =
+  let value = Id.to_string session.id in
+  let max_age = Ptime.diff session.expires_at (now ()) in
+  let max_age = Option.some @@ Ptime.Span.to_float_s max_age in
+  Cookie.make_set_headers ~encrypt:false ~max_age ~key:"drame.session" ~value
+
+let pp fmt request =
+  let { id; expires_at; payload } = load request in
+  Fmt.pf fmt "id = %a ; expires_at = %a ; payload:@\n  @[<v>" Id.pp id Ptime.pp
+    expires_at;
+  Fmt.list
+    ~sep:(fun fmt () -> Fmt.string fmt "@\n")
+    (fun fmt (k, v) -> Fmt.pf fmt "%s = %s" k v)
+    fmt payload;
+  Fmt.pf fmt "@]"
diff --git a/src/session.mli b/src/session.mli
new file mode 100644
index 0000000..d62ec1d
--- /dev/null
+++ b/src/session.mli
@@ -0,0 +1,16 @@
+type t
+
+val load : Request.t -> t
+
+val invalidate : Request.t -> unit
+
+val get : Request.t -> string -> string option
+
+val set : Request.t -> string -> string -> unit
+
+val drop : Request.t -> string -> unit
+
+val pp : Format.formatter -> Request.t -> unit
+
+(* Internal *)
+val make_send_headers : t -> (string * string) list
diff --git a/src/status.ml b/src/status.ml
new file mode 100644
index 0000000..1569d57
--- /dev/null
+++ b/src/status.ml
@@ -0,0 +1,31 @@
+type error =
+  | Moved_permanently of string
+  | Found of string
+  | See_other of string
+  | Bad_request
+  | Unauthorized
+  | Forbidden
+  | Not_found
+  | Request_timeout
+  | Too_many_requests
+  | Internal_server_error
+  | Not_implemented
+  | Bad_gateway
+  | Service_unavailable
+  | Gateway_timeout
+
+let to_httpcats = function
+  | Moved_permanently _url -> `Moved_permanently
+  | Found _url -> `Found
+  | See_other _url -> `See_other
+  | Bad_request -> `Bad_request
+  | Unauthorized -> `Unauthorized
+  | Forbidden -> `Forbidden
+  | Not_found -> `Not_found
+  | Request_timeout -> `Request_timeout
+  | Too_many_requests -> `Enhance_your_calm
+  | Internal_server_error -> `Internal_server_error
+  | Not_implemented -> `Not_implemented
+  | Bad_gateway -> `Bad_gateway
+  | Service_unavailable -> `Service_unavailable
+  | Gateway_timeout -> `Gateway_timeout
diff --git a/src/status.mli b/src/status.mli
new file mode 100644
index 0000000..635ba9b
--- /dev/null
+++ b/src/status.mli
@@ -0,0 +1,17 @@
+type error =
+  | Moved_permanently of string
+  | Found of string
+  | See_other of string
+  | Bad_request
+  | Unauthorized
+  | Forbidden
+  | Not_found
+  | Request_timeout
+  | Too_many_requests
+  | Internal_server_error
+  | Not_implemented
+  | Bad_gateway
+  | Service_unavailable
+  | Gateway_timeout
+
+val to_httpcats : error -> Httpcats.Status.t
diff --git a/src/syntax.ml b/src/syntax.ml
new file mode 100644
index 0000000..aea9713
--- /dev/null
+++ b/src/syntax.ml
@@ -0,0 +1,3 @@
+let ( let* ) = Result.bind
+
+let ( let+ ) r f = Result.map f r