Use copier for template initialization

.copier-answers.yml.jinja

@@ -0,0 +1,2 @@
+# Changes here will be overwritten by Copier; NEVER EDIT MANUALLY
+{{ _copier_answers|to_nice_yaml -}}

.github/workflows/ci.yaml

@@ -6,19 +6,40 @@ on:
       - master
   pull_request:
 jobs:
-  build:
+  template-test:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
         os: [ubuntu-latest, macos-latest]
     steps:
       - uses: actions/checkout@v4
       - uses: nixbuild/nix-quick-install-action@v33
-      - name: Install omnix
-        run: | 
-          nix --accept-flake-config profile install "github:juspay/omnix"
-          nix --version
-      - name: Build all flake outputs
-        run: om ci
+
+      - name: Install copier
+        run: nix profile install nixpkgs#copier
+
+      - name: Test template initialization with copier
+        run: |
+          # Initialize template with sample variables
+          copier copy --defaults \
+            --data author="Test Author" \
+            --data package_name="test-project" \
+            --data vscode=false \
+            --data github_ci=false \
+            . ../test-project
+
+          cd ../test-project
+
+          # Verify templating worked
+          grep "Test Author" LICENSE
+          grep "test-project" test-project.cabal
+          test -f test-project.cabal  # Verify cabal file has templated name
+
+          # Build the project
+          nix build
+
+          # Run the executable
+          ./result/bin/test-project
+
       - name: What GHC version?
         run: nix develop -c ghc --version

.gitignore

@@ -12,3 +12,12 @@ result-*
 .direnv
 
 /.pre-commit-config.yaml
+
+# LLM
+/.claude/settings.local.json
+
+# Template working files (originals are in .jinja files)
+LICENSE
+haskell-template.cabal
+src/Main.hs
+nix/modules/flake/haskell.nix

LICENSE → LICENSE.jinja

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) 2022 Sridhar Ratnakumar
+Copyright (c) {{ '%Y' | strftime }} {{ author }}
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -16,8 +16,7 @@ If you have an *existing* Haskell project, you should probably use https://githu
 Initialize this template using:
 
 ```sh
-nix run nixpkgs#omnix -- \
-  init github:srid/haskell-template -o ./yourproject
+nix run nixpkgs#copier -- copy gh:srid/haskell-template ./yourproject
 ```
 
 *tldr: [Install Nix](https://nixos.asia/en/install), [setup direnv](https://nixos.asia/en/direnv), open in VSCode, install recommended extensions and run `just run`.*

copier.yml

@@ -0,0 +1,42 @@
+# Copier template configuration for haskell-template
+# https://copier.readthedocs.io/
+
+_min_copier_version: "9.0.0"
+
+# Answers file location
+_answers_file: .copier-answers.yml
+
+# Template questions
+author:
+  type: str
+  help: Author name
+  default: Sridhar Ratnakumar
+  placeholder: "{{ author }}"
+
+package_name:
+  type: str
+  help: Name of the Haskell package
+  default: haskell-template
+  placeholder: "{{ package_name }}"
+
+vscode:
+  type: bool
+  help: Include the VSCode settings folder (./.vscode)?
+  default: true
+
+github_ci:
+  type: bool
+  help: Include GitHub Actions workflow configuration (./.github)?
+  default: true
+
+# Exclude patterns based on user choices
+_exclude:
+  - "{% if not vscode %}.vscode{% endif %}"
+  - "{% if not github_ci %}.github{% endif %}"
+  - .git
+  - .copier-answers.yml
+  - "*.pyc"
+  - __pycache__
+
+# Use .jinja suffix for templates
+_templates_suffix: .jinja

nix/modules/flake/haskell.nix → nix/modules/flake/haskell.nix.jinja

@@ -16,7 +16,7 @@
         inherit root;
         fileset = lib.fileset.unions [
           (root + /src)
-          (root + /haskell-template.cabal)
+          (root + /{{ package_name }}.cabal)
           (root + /LICENSE)
           (root + /README.md)
         ];
@@ -37,7 +37,7 @@
 
       # Add your package overrides here
       settings = {
-        haskell-template = {
+        {{ package_name }} = {
           stan = true;
           # haddock = false;
         };
@@ -53,7 +53,7 @@
     };
 
     # Default package & app.
-    packages.default = self'.packages.haskell-template;
-    apps.default = self'.apps.haskell-template;
+    packages.default = self'.packages.{{ package_name }};
+    apps.default = self'.apps.{{ package_name }};
   };
 }

src/Main.hs → src/Main.hs.jinja

@@ -17,4 +17,4 @@ main :: IO ()
 main = do
   -- For withUtf8, see https://serokell.io/blog/haskell-with-utf8
   Utf8.withUtf8 $ do
-    putTextLn "Hello 🌎 (from haskell-template)"
+    putTextLn "Hello 🌎 (from {{ package_name }})"

haskell-template.cabal → {{ package_name }}.cabal.jinja

@@ -1,12 +1,12 @@
 cabal-version:      2.4
-name:               haskell-template
+name:               {{ package_name }}
 version:            0.1.0.0
 license:            MIT
-copyright:          2022 Sridhar Ratnakumar
+copyright:          {{ '%Y' | strftime }} {{ author }}
 maintainer:         srid@srid.ca
-author:             Sridhar Ratnakumar
+author:             {{ author }}
 category:           Web
-homepage:           https://srid.ca/haskell-template
+homepage:           https://github.com/srid/haskell-template
 
 -- TODO: Before hackage release.
 -- A short (one-line) description of the package.
@@ -63,6 +63,6 @@ common shared
   hs-source-dirs:     src
   default-language:   GHC2021
 
-executable haskell-template
+executable {{ package_name }}
   import:  shared
   main-is: Main.hs