feat: Migrate CLI to haskell.nix Infrastructure for Enhanced Build Capabilities (#199)

* feat(cli): Organize event model into enterprise-grade structure

Refactor the monolithic event model in Neo.hs into a proper layered architecture:
- Domain layer: Types, Commands, Events, and Entity logic
- ReadModels layer: Query-optimized views separated by concern
- Maintain clean separation between write and read models

This structure improves maintainability and scalability for enterprise applications.

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

Co-Authored-By: Claude <noreply@anthropic.com>

* wip

* wip

* Enhances Nix development shell with HLS configuration

Adds automatic hie.yaml generation for improved Haskell Language Server integration

Configures direct cradle with proper package database paths and dependencies

Includes informative shell hook messages for better developer experience

Fixes source override path construction for nhcore dependency

* fix build for cli-next

* refactor(nix): extract common configuration into reusable module

Creates shared configuration for GHC options and language extensions
Consolidates project setup logic to reduce code duplication
Streamlines cabal file generation with centralized formatting
Improves maintainability across build and shell environments

* format

* move cli-next out of main repo

* bump

* bump

* Migrate to haskell.nix for user projects

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

Co-Authored-By: Claude <noreply@anthropic.com>

* Fix CLI parameter naming for remote SHA approach

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

Co-Authored-By: Claude <noreply@anthropic.com>

* add back a project

* Revert "feat(cli): Use nix instead of file generation for builds (#191)"

This reverts commit be27451.

* docs: improve formatting and remove outdated migration files

Enhances documentation readability by adding proper spacing around headers and sections

Removes obsolete haskell.nix migration documentation and associated Nix configuration files that are no longer needed

* necromancy

* bump

* fix old compilation

* add module  to iignore

* bring back haskell.nix

* bump

* Moves static file embedding from File to Text module

Relocates file embedding functionality to better align with its primary use case of generating text content at compile time

Renames the quasi-quoter for clearer intent and adds UTF-8 decoding to handle text files properly

Removes embedding feature from file I/O module to maintain separation of concerns between runtime file operations and compile-time content generation

* Refactors Nix configuration to create reusable project template

Extracts hardcoded project configuration into a generic function that accepts project name and source path as parameters

Moves original project-specific configuration to a new wrapper file that uses the generic template

Enables code reuse across multiple Haskell projects while maintaining the same build configuration

* Adds nixfmt formatting and fixes trailing whitespace

Enables nixfmt-rfc-style hook for consistent Nix code formatting
Removes trailing whitespace from shell function definitions

* compile

* Refactors Haskell project function interface

Changes function signature from positional arguments to named parameters using attribute set

Improves code clarity and maintainability by making function calls more explicit and self-documenting

* refactor(build): consolidate nix configuration and update templates

Moves haskell-project.nix into cli directory and embeds it directly in templates
Removes dependency on external nix files by inlining haskell.nix configuration
Adds cabal.project template for improved dependency management
Updates import formatting for consistency

Simplifies build system by reducing file dependencies and improving portability

* chore(cli-next): remove Nix build configuration

Cleans up project by removing unused Haskell.nix build setup

Adds file to gitignore to prevent future tracking

* Generates cabal project file during build process

Removes hardcoded cabal project configuration and adds dynamic generation through template system

Improves build flexibility by allowing project-specific cabal configurations

* Moves launcher to hidden directory

Relocates executable source from app to .launcher folder
Updates build configuration to use new launcher location
Adds .launcher directory to gitignore

Improves project organization by hiding build artifacts

* Passes Nix expression directly to nix-build command

Removes file-based Nix workflow by eliminating default.nix file creation and writing operations

Passes Nix template directly as command line argument using -E flag instead of creating temporary file

Streamlines build process and reduces filesystem operations

* fix shell

* feat(install): add binary cache support for faster builds

Enhances installation script with configurable binary cache setup to reduce build times from hours to minutes

Prompts user for permission before modifying system Nix configuration
Safely handles existing cache configurations without duplicates
Improves user experience with better feedback and troubleshooting guidance

* fixes

* Use main for now

* bump version

* typo

* use correct path

---------

Co-authored-by: Claude <noreply@anthropic.com>

Author: NickSeagull

.gitignore

@@ -41,3 +41,13 @@ sandbox/*.nix
 
 example.cabal
 result
+
+.claude/settings.local.json
+
+cli-next/default.nix
+
+cli-next/cabal.project
+
+cli-next/.launcher/
+
+cli-next/neo-sandbox.cabal

.vscode/settings.json

@@ -9,11 +9,13 @@
     "devenv",
     "dont",
     "foldl",
+    "fourmolu",
     "fprint",
     "GADT",
+    "haskellnix",
+    "HIEYAML",
     "hlint",
     "Hspec",
-    "Impredicative",
     "Inspectable",
     "Monoid",
     "Nanotime",
@@ -32,8 +34,7 @@
     "snoc",
     "testlib",
     "typeclasses",
-    "Unagi",
-    "Werror"
+    "Unagi"
   ],
   "nixEnvSelector.nixFile": "${workspaceFolder}/shell.nix",
   // Haskell

CLAUDE.md

@@ -13,6 +13,7 @@ NeoHaskell is a dialect of Haskell focused on newcomer-friendliness and producti
 ## Development Setup
 
 Required tools:
+
 - Install [Nix](https://nixos.org/download/)
 - Run `nix-shell` to enter development environment
 - Run `cabal update && cabal build all` to build everything
@@ -22,23 +23,28 @@ The project uses VS Code with Haskell Language Server for development.
 ## Build and Test Commands
 
 ### Core Commands
+
 - `cabal build all` - Build all packages
 - `cabal test` - Run all tests
 - `cabal test nhcore-test` - Run core library tests only
 - `cabal test nhcli-test` - Run CLI tests only
 - `hlint .` - Run linter
 
 ### Documentation Tests
+
 - `./scripts/run-doctest` - Run doctest (installs doctest if needed)
 
 ### Formatting
+
 - Code auto-formats on save in VS Code using fourmolu
 - Configuration in `fourmolu.yaml` (2-space indent, 120 char limit)
 
 ## Architecture
 
 ### Core Library Structure
+
 The core library (`nhcore`) provides NeoHaskell's standard library organized into:
+
 - **Core modules**: Basic types (Text, Int, Array, Maybe, Result, etc.)
 - **System modules**: File, Directory, Path, Environment, Time, Subprocess
 - **Concurrency**: AsyncTask, Channel, Lock, ConcurrentVar
@@ -48,25 +54,30 @@ The core library (`nhcore`) provides NeoHaskell's standard library organized int
 - **Testing**: Comprehensive EventStore test suites with property-based testing
 
 ### CLI Tool
+
 The CLI (`nhcli`) provides project management commands through the `neo` executable.
 
 ## NeoHaskell Code Style
 
 NeoHaskell follows specific coding conventions (from `.cursor/rules/neohaskell-style.mdc`):
 
 ### Import Style
+
 Always import types explicitly and modules qualified:
+
 ```haskell
 import Service.Event (Event(..))
 import Service.Event qualified as Event
 ```
 
 Use `Ghc` prefix for base library imports:
+
 ```haskell
 import Data.List qualified as GhcList
 ```
 
 ### Code Structure
+
 - No point-free style - always explicit function application
 - Prefer pipe operator `|>` over nested `$`
 - Use `do` blocks for intermediate bindings (even non-monadic), no `let..in` or `where`
@@ -77,6 +88,7 @@ import Data.List qualified as GhcList
 - Use `<TypeName>.yield` instead of `pure` or `return`
 
 ### Forbidden Patterns
+
 - Never import Haskell ecosystem modules unless explicitly requested
 - Use nhcore modules instead of base/ecosystem equivalents
 - No `let..in` or `where` clauses
@@ -88,4 +100,4 @@ import Data.List qualified as GhcList
 - Adding new core modules: Add to `core/nhcore.cabal` exposed-modules
 - Adding CLI commands: Extend modules in `cli/src/Neo/`
 - Running specific tests: Use `cabal test <package-name>-test`
-- Code formatting: Automatic in VS Code, or `fourmolu --mode inplace **/*.hs`
+- Code formatting: Automatic in VS Code, or `fourmolu --mode inplace **/*.hs`

cli-next/README.md

@@ -1,10 +1,2 @@
-# Neo CLI - Next
+# TESTING STUFF
 
-This folder houses the new implementation of the `neo` CLI.
-
-The idea is that it serves as a living integration test of NeoHaskell,
-so that the main features of the language are tested within the language
-main tool itself.
-
-Once we get on parity with the current CLI, this will become the default
-implementation.

cli-next/neo.json

@@ -1,9 +1,9 @@
 {
-  "name": "neo",
-  "version": "0.0.0",
-  "description": "The NeoHaskell command line helper",
-  "author": "Nikita Tchayka",
-  "license": "Apache-2.0",
-  "dependencies": {},
-  "overrideNeohaskell": "file:///home/nick/Source/NeoHaskell"
-}
+  "name": "neo-sandbox",
+  "version": "0.0.1",
+  "description": "Your project's description",
+  "author": "Your Name",
+  "license": "ISC",
+  "dependencies": {
+  }
+}

cli-next/src/Neo.hs

@@ -0,0 +1,7 @@
+module NeoSandbox where
+
+import Core
+
+
+run :: Task Text Unit
+run = print "Hi"

cli-next/src/Neo/Model.hs

@@ -1,6 +1,6 @@
 cabal-version:      3.4
 name:               nhcli
-version:            0.8.2
+version:            0.9.0
 synopsis:           Command Line Tool for NeoHaskell
 description:        NeoHaskell is a dialect of Haskell that is focused on newcomer-friendliness and productivity.
 homepage:           https://neohaskell.org
@@ -11,7 +11,7 @@ maintainer:         nhlib@nickseagull.dev
 copyright:
 category:           Development
 build-type:         Simple
--- extra-source-files:
+extra-source-files: ../nix/haskellnix.nix, ../nix/haskell-project.nix
 
 common common_cfg
     ghc-options:  -Wall
@@ -51,12 +51,17 @@ library
     exposed-modules:
       Neo,
       Neo.Build,
+      Neo.Build.Templates.Cabal,
+      Neo.Build.Templates.CabalProject,
+      Neo.Build.Templates.Nix,
+      Neo.Build.Templates.AppMain,
       Neo.Core,
       Neo.Core.ProjectConfiguration,
       Neo.New,
       Neo.New.Templates.NeoJson,
       Neo.New.Templates.MainModule,
       Neo.Run,
+      Neo.Shell,
     -- other-modules:
     -- other-extensions:
     hs-source-dirs:   src

cli-next/src/NeoSandbox.hs

@@ -0,0 +1,28 @@
+{ pkgs }:
+
+# Generic function to create a Haskell project template
+{ projectName, src }:
+let
+  haskellNix = import (pkgs.fetchFromGitHub {
+    owner = "input-output-hk";
+    repo = "haskell.nix";
+    rev = "4d493449406ec91db804511a6d15b6f076ba40e7";
+    sha256 = "sha256-CHNMDgFfpTV5WkVhmMLf5d5qaLUjgeoziVgmgnhPGrI=";
+  }) { inherit pkgs; };
+  # Apply haskell.nix overlay
+  pkgsWithOverlay = import haskellNix.sources.nixpkgs-unstable {
+    overlays = [
+      haskellNix.overlay
+      (final: _prev: {
+        "${projectName}Project" = final.haskell-nix.cabalProject {
+          inherit src;
+          compiler-nix-name = "ghc910";
+        };
+      })
+    ];
+    inherit (haskellNix) config;
+  };
+
+  flake = pkgsWithOverlay."${projectName}Project".flake { };
+
+in flake.packages."${projectName}:exe:${projectName}"