refactoring: reintroduce nix

.github/workflows/nix.yml

@@ -0,0 +1,21 @@
+name: nix build
+
+on:
+  - push
+  - pull_request
+jobs:
+  check_nix:
+    name: Check nix build
+    runs-on: ubuntu-latest
+    steps:
+      - name: git checkout
+        uses: actions/checkout@v3
+      - name: Install Nix
+        uses: DeterminateSystems/nix-installer-action@main
+        with:
+          extra-conf: system-features = nixos-test benchmark big-parallel kvm
+      - uses: DeterminateSystems/magic-nix-cache-action@main
+      - name: Check Nix flake inputs
+        uses: DeterminateSystems/flake-checker-action@v4
+      - name: Build lib
+        run: nix build -L

flake.nix

@@ -0,0 +1,52 @@
+{
+  description = "one-time-password";
+
+  inputs = {
+    nixpkgs.url = "github:nixos/nixpkgs/nixos-23.11-small";
+    flake-utils.url = "github:numtide/flake-utils";
+    libsodium-bindings.url = "github:haskell-cryptography/libsodium-bindings";
+    chronos = {
+      url = "github:byteverse/chronos";
+      flake = false;
+    };
+  };
+
+  outputs = { self, nixpkgs, flake-utils, ... }@inputs:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = import nixpkgs{inherit system;};
+      in
+      rec
+      {
+        packages.one-time-password =
+          pkgs.haskellPackages.callCabal2nix "one-time-password" ./.
+            {
+              base32 = pkgs.haskellPackages.base32_0_4;
+              chronos = pkgs.haskellPackages.callCabal2nix "chronos" inputs.chronos {};
+              sel = inputs.libsodium-bindings.packages.${system}.sel;
+            };
+
+        defaultPackage = packages.one-time-password;
+
+        devShell =
+          let
+            scripts = pkgs.symlinkJoin {
+              name = "scripts";
+              paths = pkgs.lib.mapAttrsToList pkgs.writeShellScriptBin {
+              };
+            };
+          in
+          pkgs.mkShell {
+            buildInputs = with pkgs.haskellPackages; [
+              pkgs.libsodium
+              haskell-language-server
+              ghcid
+              cabal-install
+              scripts
+            ];
+            inputsFrom = [
+              self.defaultPackage.${system}.env
+            ];
+          };
+      });
+}

one-time-password.cabal

@@ -55,7 +55,7 @@ library
     , cryptohash-sha1  ^>=0.11
     , network-uri      ^>=2.6
     , sel              ^>=0.0
-    , text             ^>=2.1
+    , text             >=2.0    && <2.2
     , text-display     ^>=0.0
 
   ghc-options:     -Wall