diff --git a/.gitignore b/.gitignore
index c899ee71..d9ec20f1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,4 +1,5 @@
 .direnv
+***/.hypothesis
 .coverage.*
 **/qubeclan
 **/testdir
diff --git a/docs/testing.md b/docs/testing.md
index cfba2139..5dcd7f5a 100644
--- a/docs/testing.md
+++ b/docs/testing.md
@@ -22,6 +22,11 @@ To implement property-based testing in FastAPI, you can use the following framew
 - [Schemathesis](https://schemathesis.readthedocs.io/en/stable/#id2)
 - [Hypothesis: Property-Based Testing](https://hypothesis.readthedocs.io/en/latest/quickstart.html)
 
+
+### Nix code
+https://github.com/kadena-io/signing-api/blob/master/schema-tests.nix
+https://github.com/garbas/cicero/blob/67acaaa6f568d6f5032419bdcf0f4c97fb46e5ec/pkgs/schemathesis.nix#L5
+
 ### Why Schemas Are Not Contracts
 
 A schema is a description of the data structure of your API, whereas a contract defines not only the structure but also the expected behavior and constraints. The following resource explains why schemas are not contracts in more detail:
@@ -38,6 +43,8 @@ Contract-driven testing combines the benefits of type annotations and property-b
 
 - Contracts, like property-based tests, allow you to specify conditions and constraints, with the testing framework automatically generating test cases and verifying call results.
 
+
+
 ### Frameworks for Contract-Driven Testing
 
 To implement contract-driven testing in FastAPI, consider the following framework and extension:
@@ -45,4 +52,6 @@ To implement contract-driven testing in FastAPI, consider the following framewor
 - [iContract: Contract-Driven Development](https://icontract.readthedocs.io/en/latest/introduction.html)
 - [FastAPI-iContract: Extension for FastAPI](https://github.com/mristin/fastapi-icontract)
 
-By adopting contract-driven testing, you can ensure that your FastAPI application not only has a well-defined structure but also behaves correctly, making it more robust and reliable.
\ No newline at end of file
+By adopting contract-driven testing, you can ensure that your FastAPI application not only has a well-defined structure but also behaves correctly, making it more robust and reliable.
+
+**However: icontract uses a 3 year old version of deal and a 3 year old version of typeguard. And icontract-fastapi is not maintained anymore**
\ No newline at end of file
diff --git a/flake.lock b/flake.lock
index 06a001f2..5000742f 100644
--- a/flake.lock
+++ b/flake.lock
@@ -62,11 +62,11 @@
     },
     "luispkgs": {
       "locked": {
-        "lastModified": 1699286483,
-        "narHash": "sha256-gzY56MbP3UTztI7Ra69RCNq81fKlsQu79LZ2gGss3Eg=",
+        "lastModified": 1699386673,
+        "narHash": "sha256-T9ZrVSf0ymSBHFpRw7K+DSNzY0sCkwkDe0VIzE033Ac=",
         "owner": "Luis-Hebendanz",
         "repo": "nixpkgs",
-        "rev": "b59438a5a3b4d50e117081d41ed6f8833f65934d",
+        "rev": "e918074d416f0918ac6c3895c6a5db2ae5ce3c1e",
         "type": "github"
       },
       "original": {
diff --git a/flake.nix b/flake.nix
index a222e4f7..cebc496b 100644
--- a/flake.nix
+++ b/flake.nix
@@ -9,6 +9,7 @@
     #nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable-small";
     # https://github.com/NixOS/nixpkgs/pull/265872
     luispkgs.url = "github:Luis-Hebendanz/nixpkgs/fix_python_deal";
+
     floco.url = "github:aakropotkin/floco";
     floco.inputs.nixpkgs.follows = "nixpkgs";
     disko.url = "github:nix-community/disko";
@@ -32,6 +33,7 @@
         "aarch64-darwin"
       ];
       imports = [
+
         ./checks/flake-module.nix
         ./devShell.nix
         ./formatter.nix
diff --git a/pkgs/clan-cli/default.nix b/pkgs/clan-cli/default.nix
index 9cf55b12..4dc13659 100644
--- a/pkgs/clan-cli/default.nix
+++ b/pkgs/clan-cli/default.nix
@@ -34,8 +34,8 @@
 , gnupg
 , e2fsprogs
 , mypy
-, cntr
 , deal
+, schemathesis
 }:
 let
 
@@ -58,6 +58,7 @@ let
     gnupg
     stdenv.cc
     deal
+    schemathesis
   ];
 
   # Optional dependencies for clan cli, we re-expose them here to make sure they all build.
diff --git a/pkgs/clan-cli/flake-module.nix b/pkgs/clan-cli/flake-module.nix
index afba1380..7a230dab 100644
--- a/pkgs/clan-cli/flake-module.nix
+++ b/pkgs/clan-cli/flake-module.nix
@@ -1,20 +1,25 @@
 { inputs, ... }:
 {
-  perSystem = { self', pkgs, system, ... }: {
-    devShells.clan-cli = pkgs.callPackage ./shell.nix {
-      inherit (self'.packages) clan-cli ui-assets nix-unit;
-    };
-    packages = {
-      clan-cli = pkgs.python3.pkgs.callPackage ./default.nix {
-        inherit (self'.packages) ui-assets;
-        inherit (inputs) nixpkgs;
-        deal = inputs.luispkgs.legacyPackages.${system}.python3Packages.deal;
+  perSystem = { self', pkgs, system, ... }:
+    let
+      luisPythonPkgs = inputs.luispkgs.legacyPackages.${system}.python3Packages;
+    in
+    {
+      devShells.clan-cli = pkgs.callPackage ./shell.nix {
+        inherit (self'.packages) clan-cli ui-assets nix-unit;
+      };
+      packages = {
+        clan-cli = pkgs.python3.pkgs.callPackage ./default.nix {
+          inherit (self'.packages) ui-assets;
+          inherit (inputs) nixpkgs;
+          deal = luisPythonPkgs.deal;
+          schemathesis = luisPythonPkgs.schemathesis;
+        };
+        inherit (self'.packages.clan-cli) clan-openapi;
+        default = self'.packages.clan-cli;
       };
-      inherit (self'.packages.clan-cli) clan-openapi;
-      default = self'.packages.clan-cli;
-    };
 
-    checks = self'.packages.clan-cli.tests;
-  };
+      checks = self'.packages.clan-cli.tests;
+    };
 
 }