diff --git a/.nix/no-web.patch b/.nix/no-web.patch
deleted file mode 100644
index 5342d8ee..00000000
--- a/.nix/no-web.patch
+++ /dev/null
@@ -1,56 +0,0 @@
-diff --git a/compiler/catala_web_interpreter.ml b/compiler/catala_web_interpreter.ml
-deleted file mode 100644
-index 3b8d660..0000000
---- a/compiler/catala_web_interpreter.ml
-+++ /dev/null
-@@ -1,29 +0,0 @@
--open Driver
--open Js_of_ocaml
--
--let _ =
--  Js.export_all
--    (object%js
--       method interpret
--           (contents : Js.js_string Js.t)
--           (scope : Js.js_string Js.t)
--           (language : Js.js_string Js.t)
--           (trace : bool) =
--         driver
--           (Contents (Js.to_string contents))
--           {
--             Utils.Cli.debug = false;
--             unstyled = false;
--             wrap_weaved_output = false;
--             avoid_exceptions = false;
--             backend = "Interpret";
--             language = Some (Js.to_string language);
--             max_prec_digits = None;
--             closure_conversion = false;
--             trace;
--             disable_counterexamples = false;
--             optimize = false;
--             ex_scope = Some (Js.to_string scope);
--             output_file = None;
--           }
--    end)
-diff --git a/compiler/dune b/compiler/dune
-index 2c5a1996..f6c38809 100644
---- a/compiler/dune
-+++ b/compiler/dune
-@@ -19,16 +19,6 @@
-  (libraries calendar zarith zarith_stubs_js)
-  (modules runtime))
-
--(executable
-- (name catala_web_interpreter)
-- (modes byte js)
-- (package catala)
-- (public_name catala_web_interpreter)
-- (modules catala_web_interpreter)
-- (preprocess
--  (pps js_of_ocaml-ppx))
-- (libraries catala.driver js_of_ocaml))
--
- (executable
-  (name catala)
-  (modes native js)
diff --git a/.nix/packages.nix b/.nix/packages.nix
new file mode 100644
index 00000000..3c34c98b
--- /dev/null
+++ b/.nix/packages.nix
@@ -0,0 +1,19 @@
+{ ocamlPackages, fetchurl }:
+
+ocamlPackages.overrideScope' (self: super: {
+  cmdliner_1_1_0 = super.cmdliner.overrideAttrs (o: rec {
+    version = "1.1.0";
+    src = fetchurl {
+      url = "https://erratique.ch/software/${o.pname}/releases/${o.pname }-${version}.tbz";
+      sha256 = "sha256-irWd4HTlJSYuz3HMgi1de2GVL2qus0QjeCe1WdsSs8Q=";
+    };
+  });
+  alcotest = (super.alcotest.override {
+    cmdliner = self.cmdliner_1_1_0;
+  }).overrideAttrs (_: {
+    doCheck = false;
+  });
+  bindlib = ocamlPackages.callPackage ./bindlib.nix { };
+  unionfind = ocamlPackages.callPackage ./unionfind.nix { };
+  ppx_yojson_conv = ocamlPackages.callPackage ./ppx_yojson_conv.nix { };
+})
diff --git a/.nix/ppx_yojson_conv.nix b/.nix/ppx_yojson_conv.nix
new file mode 100644
index 00000000..6b5e14b3
--- /dev/null
+++ b/.nix/ppx_yojson_conv.nix
@@ -0,0 +1,20 @@
+{ lib, fetchurl, buildDunePackage, ppxlib, ppx_yojson_conv_lib, ppx_js_style }:
+
+buildDunePackage rec {
+  pname = "ppx_yojson_conv";
+  version = "0.14.0";
+
+  minimumOCamlVersion = "4.0.8";
+
+  useDune2 = true;
+
+  propagatedBuildInputs = [
+    ppxlib ppx_yojson_conv_lib ppx_js_style
+  ];
+
+  src = fetchurl
+    {
+      url = "https://ocaml.janestreet.com/ocaml-core/v0.14/files/ppx_yojson_conv-v0.14.0.tar.gz";
+      sha256 = "0ls6vzj7k0wrjliifqczs78anbc8b88as5w7a3wixfcs1gjfsp2w";
+    };
+}
diff --git a/default.nix b/default.nix
index 0ae0adfd..72703841 100644
--- a/default.nix
+++ b/default.nix
@@ -7,7 +7,7 @@
 , menhir
 , unionfind
 , bindlib
-, cmdliner
+, cmdliner_1_1_0
 , re
 , zarith
 , zarith_stubs_js
@@ -22,12 +22,13 @@
 , ppx_deriving
 , z3
 , alcotest
+, ppx_yojson_conv
 , menhirLib ? null #for nixos-unstable compatibility.
 }:
 
 buildDunePackage rec {
   pname = "catala";
-  version = "0.5.0";
+  version = "0.6.0"; # TODO parse `catala.opam` with opam2json
 
   minimumOCamlVersion = "4.11";
 
@@ -40,7 +41,7 @@ buildDunePackage rec {
     sedlex_2
     menhir
     menhirLib
-    cmdliner
+    cmdliner_1_1_0
     re
     zarith
     zarith_stubs_js
@@ -50,6 +51,7 @@ buildDunePackage rec {
     benchmark
     js_of_ocaml
     js_of_ocaml-ppx
+    ppx_yojson_conv
     camomile
     cppo
     z3
@@ -65,8 +67,6 @@ buildDunePackage rec {
   ] ++ (if isNull menhirLib then [ ] else [ menhirLib ]);
   doCheck = true;
 
-  patches = [ ./.nix/no-web.patch ];
-
   meta = with lib; {
     homepage = "https://catala-lang.org";
     description =
diff --git a/flake.lock b/flake.lock
new file mode 100644
index 00000000..d5f1ab2b
--- /dev/null
+++ b/flake.lock
@@ -0,0 +1,43 @@
+{
+  "nodes": {
+    "flake-utils": {
+      "locked": {
+        "lastModified": 1653893745,
+        "narHash": "sha256-0jntwV3Z8//YwuOjzhV2sgJJPt+HY6KhU7VZUL0fKZQ=",
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "rev": "1ed9fb1935d260de5fe1c2f7ee0ebaae17ed2fa1",
+        "type": "github"
+      },
+      "original": {
+        "owner": "numtide",
+        "repo": "flake-utils",
+        "type": "github"
+      }
+    },
+    "nixpkgs": {
+      "locked": {
+        "lastModified": 1653581809,
+        "narHash": "sha256-Uvka0V5MTGbeOfWte25+tfRL3moECDh1VwokWSZUdoY=",
+        "owner": "NixOS",
+        "repo": "nixpkgs",
+        "rev": "83658b28fe638a170a19b8933aa008b30640fbd1",
+        "type": "github"
+      },
+      "original": {
+        "owner": "NixOS",
+        "ref": "nixos-unstable",
+        "repo": "nixpkgs",
+        "type": "github"
+      }
+    },
+    "root": {
+      "inputs": {
+        "flake-utils": "flake-utils",
+        "nixpkgs": "nixpkgs"
+      }
+    }
+  },
+  "root": "root",
+  "version": 7
+}
diff --git a/flake.nix b/flake.nix
new file mode 100644
index 00000000..2136854e
--- /dev/null
+++ b/flake.nix
@@ -0,0 +1,33 @@
+{
+  inputs = {
+    flake-utils.url = github:numtide/flake-utils;
+    nixpkgs.url = github:NixOS/nixpkgs/nixos-unstable;
+  };
+
+  outputs = {nixpkgs, flake-utils, ...}:
+    let
+      systems = [ "x86_64-linux" ];
+    in flake-utils.lib.eachSystem systems (system:
+      let
+        pkgs = import nixpkgs { inherit system; };
+        ocamlPackages = pkgs.callPackage ./.nix/packages.nix {};
+      in
+        rec {
+          packages = {
+            catala = ocamlPackages.callPackage ./. {};
+          };
+          defaultPackage = packages.catala;
+          devShell = pkgs.mkShell {
+            inputsFrom = [packages.catala];
+            buildInputs = [
+              pkgs.inotify-tools
+              ocamlPackages.merlin
+              pkgs.ocamlformat
+              ocamlPackages.ocp-indent
+              ocamlPackages.utop
+              ocamlPackages.ocaml-lsp
+            ];
+          };
+        }
+    );
+}
diff --git a/release.nix b/release.nix
deleted file mode 100644
index f1859d38..00000000
--- a/release.nix
+++ /dev/null
@@ -1,7 +0,0 @@
-{ pkgs ? import <nixpkgs> { } }:
-
-with pkgs;
-ocamlPackages.callPackage ./. {
-  bindlib = ocamlPackages.callPackage ./.nix/bindlib.nix { };
-  unionfind = ocamlPackages.callPackage ./.nix/unionfind.nix { };
-}
diff --git a/shell.nix b/shell.nix
deleted file mode 100644
index 9470086e..00000000
--- a/shell.nix
+++ /dev/null
@@ -1,19 +0,0 @@
-{ pkgs ? import <nixpkgs> { } }:
-
-with pkgs;
-let
-  pkg = ocamlPackages.callPackage ./. {
-    bindlib = ocamlPackages.callPackage ./.nix/bindlib.nix { };
-    unionfind = ocamlPackages.callPackage ./.nix/unionfind.nix { };
-  };
-in mkShell {
-  inputsFrom = [ pkg ];
-  buildInputs = pkg.propagatedBuildInputs ++ [
-    inotify-tools
-    ocamlPackages.merlin
-    ocamlformat
-    ocamlPackages.ocp-indent
-    ocamlPackages.utop
-    ocamlPackages.ocaml-lsp
-  ];
-}