Add flake

flake.nix

@@ -0,0 +1,69 @@
+{
+  description = "Anki decks hosted on patrickstevens.co.uk";
+
+  inputs = {
+    flake-utils.url = github:numtide/flake-utils;
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-22.11";
+    anki-compiler.url = "github:Smaug123/anki-dotnet";
+  };
+
+  outputs = {
+    self,
+    nixpkgs,
+    flake-utils,
+    anki-compiler,
+  }: let
+    commit = self.shortRev or "dirty";
+    date = self.lastModifiedDate or self.lastModified or "19700101";
+    version = "1.0.0+${builtins.substring 0 8 date}.${commit}";
+  in
+    flake-utils.lib.eachDefaultSystem (system: let
+      pkgs = nixpkgs.legacyPackages.${system};
+    in let
+      createShellScript = name: contents:
+        pkgs.stdenv.mkDerivation {
+          __contentAddressed = true;
+          pname = name;
+          version = "0.1.0";
+          src = contents;
+
+          buildInputs = [
+            pkgs.shellcheck
+          ];
+
+          phases = ["configurePhase" "buildPhase" "installPhase"];
+
+          configurePhase = ''
+            ${pkgs.shellcheck}/bin/shellcheck "${contents}"
+          '';
+
+          buildPhase = ''
+            cp "${contents}" run.sh
+            patchShebangs run.sh
+            sed -i 's_"/bin/bash"_"${pkgs.bash}/bin/bash"_' run.sh
+            sed -i 's_"/bin/sh"_"${pkgs.bash}/bin/bash"_' run.sh
+          '';
+
+          installPhase = ''
+            mkdir -p $out
+            mv run.sh $out/run.sh
+          '';
+        };
+    in let
+      buildAnki = createShellScript "anki" ./build.sh;
+    in {
+      packages.default = pkgs.stdenv.mkDerivation {
+        __contentAddressed = true;
+        inherit version;
+        pname = "patrickstevens.co.uk-anki";
+        src = ./.;
+        buildInputs = [];
+        installPhase = ''
+          ${buildAnki}/run.sh . "${anki-compiler.packages.${system}.default}/bin/AnkiStatic" "$out"
+        '';
+      };
+      devShells.default = pkgs.mkShell {
+        buildInputs = [pkgs.alejandra pkgs.shellcheck];
+      };
+    });
+}