nixy

Nixy

Simple, powerful Nix development environments without the complexity.

Why Nixy?

Nixy bridges the gap between Nix's powerful reproducibility and developer-friendly simplicity. Write a simple YAML file, get a fully reproducible development environment - no Nix knowledge required.

Quick Start

# Initialize a new project
nixy init

# Enter development shell
nixy shell

# Build your project
nixy build <build-name>

Auto Jump into nixy shell

function __nixy_shell_activate --on-variable PWD
  if not status is-interactive
    return
  end

  if test -n "$NIXY_SHELL"
    return
  end

  if not test -e nixy.yml
    return
  end

  set value (fzf --reverse --prompt "Load nixy shell ? " < (printf "YES\nNO" | psub))

  if test -z $value
    set value "YES"
  end

  if test "$value" = "NO"
    return
  end

  exec nixy shell
end

if status is-interactive
  __nixy_shell_activate
end

Installation

Pre-built Binary (Recommended)

Download from releases page

From Source

go install github.com/nxtcoder17/nixy/cmd@latest

Using Nix

nix run github:nxtcoder17/nixy -- shell

Core Features

🎯 Simple YAML Configuration

No more complex Nix expressions. Just list what you need:

nixpkgs: abc123  # Optional: pin nixpkgs version

packages:
  - nodejs
  - python3
  - go

libraries:      # System libraries
  - zlib
  - openssl

shellHook: |    # Shell initialization
  echo "Welcome to your dev environment!"

📦 Advanced Package Management

Nixpkgs Packages

packages:
  - nodejs                    # Latest from pinned nixpkgs
  - go_1_21                  # Specific version
  - nixpkgs/abc123#golang    # Package from specific commit

URL Packages

Download and install packages directly from URLs with environment variable expansion:

packages:
  - name: kubectl
    url: https://dl.k8s.io/release/v1.28.0/bin/linux/amd64/kubectl
    sha256: "abc123..."  # Optional, auto-fetched if not provided
    
  - name: terraform
    url: https://releases.hashicorp.com/terraform/1.6.0/terraform_1.6.0_linux_amd64.zip
    # Automatically detects archive type and extracts
    
  # Environment variables are expanded in URLs
  - name: my-tool
    url: https://github.com/org/tool/releases/download/v${MY_VERSION}/tool-${NIXY_OS}-${NIXY_ARCH}.tar.gz
    # Uses MY_VERSION from env section and built-in NIXY_* vars

env:
  MY_VERSION: "1.2.3"  # Custom env vars can be used in URLs

Built-in environment variables available:

• NIXY_OS - Operating system (e.g., linux, darwin)
• NIXY_ARCH - Architecture (e.g., amd64, arm64)
• NIXY_FULL_ARCH - Full architecture string (e.g., x86_64)

🔧 Build System

Define reproducible builds:

builds:
  my-app:
    package:
      - out/my-binary
      - config.json
    hook: |
      go build -o out/my-binary ./cmd/main.go

🏃 Multiple Execution Backends

Local (Default)

Uses your system's Nix installation:

nixy shell

Docker

Perfect for CI/CD pipelines:

NIXY_EXECUTOR=docker nixy shell

Bubblewrap (Sandboxed)

Strong isolation with automatic static nix binary download - no systemwide Nix installation required:

NIXY_EXECUTOR=bubblewrap nixy shell

👤 Profile Management

[!NOTE] Profiles give file system isolation, different dev shells in the same profile, share some filesystem like nix-store, fake-home etc.

Keep separate development profiles:

# Create profiles
nixy profile create work
nixy profile create personal

# Use a profile
NIXY_PROFILE=work nixy shell

# List profiles
nixy profile list

Advanced Features

🌐 Mixed Package Sources

Combine packages from different nixpkgs versions:

packages:
  - nodejs                           # From pinned nixpkgs
  - nixpkgs/9d1fa9fa266631335618373f8faad570df6f9ede#python311        # Python from different commit
  - name: custom-tool
    url: https://example.com/tool.tar.gz

🗂️ Smart Archive Packages Handling

Automatically detects and extracts from various archive formats:

• .tar, .tar.gz, .tar.xz, .tar.bz2
• .zip, .7z, .rar
• .gz, .xz, .bz2

🔒 Pure Environments

All execution backends provide pure, reproducible environments with:

• Isolated dependencies
• Consistent behavior across machines
• No global state pollution

⚡ Intelligent Caching

• Configuration change detection via SHA256
• Rebuilds only when necessary
• Fast subsequent shells

🎨 Environment Customization

shellHook: |
  export EDITOR=vim
  alias ll='ls -la'
  echo "Environment ready!"

env:
  NODE_ENV: development
  DATABASE_URL: postgresql://localhost/myapp

Commands

Core Commands

• nixy init - Initialize a new nixy.yml
• nixy shell - Enter development shell
• nixy build [target] - Build defined targets
• nixy run <command> - Run command in nixy environment

Profile Commands

• nixy profile create <name> - Create new profile
• nixy profile list - List all profiles
• nixy profile remove <name> - Remove profile

Utility Commands

• nixy validate - Validate nixy.yml
• nixy version - Show version information

Examples

Full-Stack Development

nixpkgs: dfb2f12e899db4876308eba6d93455ab7da304cd

packages:
  # Backend
  - nodejs
  - postgresql_15
  
  # Frontend
  - pnpm
  - cypress
  
  # Tools
  - name: stripe-cli
    url: https://github.com/stripe/stripe-cli/releases/download/v1.19.1/stripe_1.19.1_linux_x86_64.tar.gz
    
libraries:
  - postgresql

Python Data Science

nixpkgs: dfb2f12e899db4876308eba6d93455ab7da304cd

packages:
  - python311
  - poetry
  - jupyter
  - nixpkgs/abc123#cudaPackages.cudatoolkit  # CUDA from specific commit

libraries:
  - zlib
  - blas
  - lapack

env:
  JUPYTER_ENABLE_LAB: "true"

Go with Kubernetes

packages:
  - go_1_21
  - golangci-lint
  - gopls
  
  # Kubernetes tools
  - name: kubectl
    url: https://dl.k8s.io/release/v1.28.0/bin/linux/amd64/kubectl
  - name: helm
    url: https://get.helm.sh/helm-v3.13.0-linux-amd64.tar.gz
  - name: k9s
    url: https://github.com/derailed/k9s/releases/download/v0.27.4/k9s_Linux_amd64.tar.gz

shellHook: |
  export KUBECONFIG=$HOME/.kube/config

Configuration Reference

nixy.yml

# Pin nixpkgs version (optional)
nixpkgs: <commit-hash>

# Package list
packages:
  - <package-name>                    # Simple package
  - nixpkgs/<commit>#<package>        # From specific commit
  - name: <name>                      # URL package
    url: <url>
    sha256: <hash>                    # Optional
    type: binary|archive              # Auto-detected

# System libraries
libraries:
  - <library-name>

# Environment variables
env:
  KEY: value

# Shell initialization
shellHook: |
  <bash commands>

# Build targets
builds:
  <target>:
    packages:
      - <package>
    paths: |
      - <file-path-1>
      - <file-path-2>

Environment Variables

• NIXY_EXECUTOR - Execution backend (local, docker, bubblewrap)
• NIXY_PROFILE - Profile name to use

Troubleshooting

"No Nix installation found"

• Install Nix, or use NIXY_EXECUTOR=bubblewrap for automatic Nix download

"Package not found"

• Check package name at search.nixos.org
• Try updating nixpkgs commit hash

"Archive extraction failed"

• Verify URL is accessible
• Check if SHA256 matches
• Ensure archive isn't corrupted

Performance Issues

• Use local executor for fastest performance

Contributing

We welcome contributions! See CONTRIBUTING.md for guidelines.

License

MIT

Acknowledgments

Built with ❤️ using:

• Nix - The powerful package manager
• Go - The programming language
• bubblewrap - Unprivileged Sandboxing tool

Making Nix accessible to everyone, one YAML at a time.