devenv 1.10: monorepo Nix support with devenv.yaml imports

devenv 1.10 brings new capabilities for structuring monorepo projects:

• absolute/parent path imports
• git root prefixing
• devenv.yaml imports
• devenv.local.yaml support
• monorepo guide

Absolute / parent path imports

Paths starting with / are now resolved from your git repository root, and parent imports are also supported (#998).

This lets services consistently reference shared configurations:

services/worker/devenv.yaml

imports:
  - /nix/devenv.nix
  - ../api/devenv.nix

This is particularly handy in monorepos where projects are nested at different depths:

my-monorepo/
├── nix/
│   └── devenv.nix       # Shared base configuration
├── services/
│   ├── api/
│   │   └── devenv.yaml  # imports: [/nix]
│   └── worker/
│       └── devenv.yaml  # imports: [/nix]
└── apps/
    └── web/
        └── devenv.yaml  # imports: [/nix]

All three projects reference /nix regardless of their location.

Git root prefixing

The new config.git.root variable provides the git repository root path for specifying working directories in tasks and processes (#1850, #316).

services/api/devenv.nix

{ config, ... }: {
  tasks."db:migrate" = {
    exec = "npm run migrate";
    cwd = "${config.git.root}/services/api";
  };

  processes.api = {
    exec = "npm start";
    cwd = "${config.git.root}/services/api";
  };
}

Useful when reusing modules across different directories.

devenv.yaml imports

Most upvoted feature with 75 votes (#14) is here!

Local imports now load and merge both devenv.nix and devenv.yaml configurations:

shared/devenv.yaml

allowUnfree: true
inputs:
  nixpkgs:
    url: github:NixOS/nixpkgs/nixpkgs-unstable

services/api/devenv.yaml

imports:
  - /shared

The API service inherits the allowUnfree setting and nixpkgs input. Note that this merging only applies to local filesystem imports — imports from inputs still only load Nix configurations (#2205).

devenv.local.yaml support

Just like devenv.local.nix, you can now use devenv.local.yaml for developer-specific overrides (#817).

Both files are git-ignored for local overrides:

devenv.local.yaml

allowUnfree: true

Monorepo guide

Check out the new Monorepo Guide for detailed examples and patterns.

Join the devenv community to share your monorepo experience!

Domen