chore: add nix flake config

Author: sunng87

flake.lock

@@ -0,0 +1,67 @@
+{
+  description = "Editor Code Assistant (ECA) - AI pair programming capabilities agnostic of editor ";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs = { self, nixpkgs, flake-utils }:
+    flake-utils.lib.eachDefaultSystem (system:
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+        jdk = pkgs.jdk24_headless;
+        graalvm = pkgs.graalvmPackages.graalvm-ce;
+        clojure = pkgs.clojure.override { jdk = pkgs.jdk_headless; };
+
+      in
+      {
+        devShells.default = pkgs.mkShell {
+          packages = with pkgs; [
+            jdk
+            clojure
+            clojure-lsp
+            babashka
+            graalvm
+            git
+          ];
+
+          env = {
+            JAVA_HOME = "${jdk}";
+            GRAALVM_HOME = "${graalvm}";
+
+          };
+
+        };
+
+        packages.default = pkgs.stdenv.mkDerivation {
+          pname = "eca";
+          version = "0.1.0";
+          src = ./.;
+
+          nativeBuildInputs = with pkgs; [
+            jdk
+            clojure
+            babashka
+            graalvm
+            git
+          ];
+
+          CLJ_CONFIG = "${placeholder "out"}/.clojure";
+          CLJ_CACHE = "${placeholder "out"}/.cpcache";
+
+          configurePhase = ''
+            mkdir -p $CLJ_CONFIG $CLJ_CACHE
+          '';
+
+          buildPhase = ''
+            bb native-cli
+          '';
+
+          installPhase = ''
+            cp eca $out/bin/
+          '';
+        };
+      }
+    );
+}