flake: add nix flake for building

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <[email protected]>

Author: aster-void

README.md

@@ -4,10 +4,25 @@ Self-updating cron scheduler that pulls job definitions from git.
 
 ## Installation
 
+### Cargo
+
 ```bash
 cargo install --path .
 ```
 
+### Nix
+
+```bash
+# Run directly
+nix run github:aster-void/rollcron -- /path/to/repo
+
+# Install to profile
+nix profile install github:aster-void/rollcron
+
+# Development shell
+nix develop
+```
+
 ## Quick Start
 
 1. Create `rollcron.yaml` in your repository:
@@ -45,6 +60,10 @@ rollcron https://github.com/user/repo --pull-interval 300
 ### rollcron.yaml
 
 ```yaml
+runner:                       # Optional: global settings
+  working_dir: ./scripts      # Working directory (relative to job dir)
+  timezone: Asia/Tokyo        # Timezone for cron schedules (default: UTC)
+
 jobs:
   <job-id>:                   # Key is the job ID (used for directories)
     name: "Display Name"      # Optional: display name (defaults to job ID)
@@ -58,6 +77,15 @@ jobs:
       delay: 1s               # Initial delay (default: 1s), exponential backoff
 ```
 
+### Runner
+
+Global settings that apply to all jobs:
+
+| Field | Description |
+|-------|-------------|
+| `working_dir` | Working directory for all jobs (relative to job snapshot dir) |
+| `timezone` | Timezone for cron schedule interpretation (e.g., `Asia/Tokyo`, `America/New_York`) |
+
 ### Concurrency
 
 Controls behavior when a job is triggered while a previous instance is still running:

flake.lock

@@ -0,0 +1,44 @@
+{
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+  };
+
+  outputs =
+    { self, nixpkgs }:
+    let
+      systems = [
+        "x86_64-linux"
+        "aarch64-linux"
+        "x86_64-darwin"
+        "aarch64-darwin"
+      ];
+      forAllSystems = f: nixpkgs.lib.genAttrs systems (system: f nixpkgs.legacyPackages.${system});
+    in
+    {
+      packages = forAllSystems (pkgs: {
+        rollcron = pkgs.rustPlatform.buildRustPackage {
+          pname = "rollcron";
+          version = "0.1.0";
+          src = ./.;
+          cargoLock.lockFile = ./Cargo.lock;
+          nativeBuildInputs = [ pkgs.makeWrapper ];
+          postInstall = ''
+            wrapProgram $out/bin/rollcron \
+              --prefix PATH : ${pkgs.lib.makeBinPath [ pkgs.git pkgs.gnutar ]}
+          '';
+        };
+        default = self.packages.${pkgs.system}.rollcron;
+      });
+
+      devShells = forAllSystems (pkgs: {
+        default = pkgs.mkShell {
+          packages = [
+            pkgs.cargo
+            pkgs.rustc
+            pkgs.rust-analyzer
+            pkgs.git
+          ];
+        };
+      });
+    };
+}