Monorepo with Shared Configurations

Added in 1.10

This guide shows how to structure a monorepo where multiple services share common configurations.

Project Structure

my-monorepo/├── shared/│   └── devenv.nix       # Shared configurations├── services/│   ├── api/│   │   ├── devenv.yaml│   │   └── devenv.nix│   └── frontend/│       ├── devenv.yaml│       └── devenv.nix

Shared Configuration

Create a shared configuration with common settings:

{ pkgs, ... }: {  packages = [    pkgs.curl    pkgs.jq  ];
  services.postgres = {    enable = true;    initialDatabases = [      { name = "myapp"; }    ];  };
  git-hooks.hooks = {    prettier.enable = true;    nixpkgs-fmt.enable = true;  };}

shared/devenv.nix

Service Configuration

API Service

Each service imports the shared configuration using an absolute import path. Paths starting with / are resolved from the repository root (where .git is located), allowing services in different directories to reference shared configurations consistently.

imports:  - /shared

services/api/devenv.yaml

{ pkgs, ... }: {  # Node.js for the API  languages.javascript = {    enable = true;    package = pkgs.nodejs_20;  };
  # API-specific environment  env = {    API_PORT = "3000";    SERVICE_NAME = "api";  };
  # API scripts  scripts = {    dev.exec = "npm run dev";    test.exec = "npm test";  };}

services/api/devenv.nix

Frontend Service

imports:  - /shared

services/frontend/devenv.yaml

{ pkgs, ... }: {  languages.javascript = {    enable = true;    package = pkgs.nodejs_20;  };
  # Frontend scripts  scripts = {    dev.exec = "npm run dev";    build.exec = "npm run build";  };}

services/frontend/devenv.nix

Referencing the Repository Root

When working in a monorepo, you often need to reference paths relative to the repository root. Use config.git.root to get the absolute path to the git repository root.

This is particularly useful for running processes from specific directories:

{ pkgs, config, ... }: {  processes.api.exec = {    exec = "npm run dev";    cwd = "${config.git.root}/services/api";  };
  processes.frontend.exec = {    exec = "npm run dev";    cwd = "${config.git.root}/services/frontend";  };}

services/api/devenv.nix

This allows you to run multiple service processes from a single devenv shell, regardless of which directory you’re in.

Working with Services

Enter a specific service environment:

cd services/apidevenv shell

Terminal window

The API service will have access to:

• All packages from shared/devenv.nix (git, curl, jq)
• The PostgreSQL database service
• Common environment variables (PROJECT_NAME, ENVIRONMENT, DATABASE_URL)
• Its own specific settings (API_PORT, SERVICE_NAME)

Similarly, the frontend service inherits the shared configuration while maintaining its own specific settings.

Last updated Oct 08, 2026