devenv-generate(1)

📦
version 2.4.0 · 2 versions
, in nixpkgs unstable

💅 devenv-generate — bestie, the AI is gonna write your config ✨

okay so real talk, this page is devenv-generate(1) from the General Commands Manual, and it's literally the glow-up your project config deserves. Stay with me, we're going through every single flag together, no skipping, no cap. 🫶

✨ NAME ✨

devenv-generate — Generate devenv.yaml and devenv.nix using AI 🧚

🌸 SYNOPSIS 🌸

devenv generate [--user-config] [--from] [-o|--override-input]
[-O|--option] [-j|--max-jobs] [-u|--cores] [-s|--system] [-i|--impure]
[--no-impure] [--offline] [--nix-option] [--nix-debugger] [-c|--clean]
[-P|--profile] [--reload] [--no-reload] [--shell] [--eval-cache]
[--no-eval-cache] [--refresh-eval-cache] [--refresh-task-cache]
[--secretspec-provider] [--secretspec-profile] [--trace-to]
[-v|--verbose] [-q|--quiet] [--tui] [--no-tui] [-h|--help]

🦋 DESCRIPTION 🦋

Generate devenv.yaml and devenv.nix using AI.

that's it, that's the whole vibe. you type it, the AI cooks, you get config files. main character energy fr fr. 👑

🎀 OPTIONS 🎀

  • --user-config <USER_CONFIG> — Use this user configuration file instead of the XDG default. like, "I brought my own, thanks bestie."

💜 INPUT OVERRIDES

  • --from <FROM> — Source for devenv.nix.

Can be either a filesystem path (with path: prefix) or a flake input reference.

Examples, copy-paste ready:

--from github:cachix/devenv
--from github:cachix/devenv?dir=examples/simple
--from path:/absolute/path/to/project
--from path:./relative/path
  • -o, --override-input <NAME> <URI> — Override inputs in devenv.yaml.

Examples:

--override-input nixpkgs github:NixOS/nixpkgs/nixos-unstable
--override-input nixpkgs path:/path/to/local/nixpkgs
  • -O, --option <OPTION:TYPE> <VALUE> — Override configuration options with typed values. typed, bestie. we're not out here guessing. 💅

OPTION must include a type: <attribute>:<type>. Supported types: string, int, float, bool, path, pkg, pkgs.

List types (pkgs) append to existing values by default. Add a ! suffix to replace instead: pkgs!.

Examples:

--option languages.rust.channel:string beta
--option services.postgres.enable:bool true
--option languages.python.version:string 3.10
--option packages:pkgs "ncdu git"       (appends to packages)
--option packages:pkgs! "ncdu git"      (replaces all packages)

🔥 NIX OPTIONS

  • -j, --max-jobs <MAX_JOBS> — Maximum number of Nix builds to run concurrently.

Defaults to 1/4 of available CPU cores (minimum 1).

  • -u, --cores <CORES> — Number of CPU cores available to each build.

Defaults to available cores divided by max-jobs (minimum 1).

  • -s, --system <SYSTEM> — Override the target system.

Defaults to the host system (e.g. aarch64-darwin, x86_64-linux).

  • -i, --impure — Relax the hermeticity of the environment.
  • --no-impure — Force a hermetic environment, overriding config. the config said one thing, this flag said "nope." 🙈
  • --offline — Disable substituters and consider all previously downloaded files up-to-date.
  • --nix-option <NAME> <VALUE> — Pass additional options to nix commands.

These options are passed directly to Nix using the --option flag. See man nix.conf for the full list of available options.

Examples:

--nix-option sandbox false
--nix-option keep-outputs true
--nix-option system x86_64-darwin
  • --nix-debugger — Enter the Nix debugger on failure. when things go sideways, you get to go in there personally. 😭

🌈 SHELL OPTIONS

  • -c, --clean [<CLEAN>...] — Ignore existing environment variables when entering the shell. Pass a list of comma-separated environment variables to let through.
  • -P, --profile <PROFILES> — Activate one or more profiles defined in devenv.nix.

Profiles allow you to define different configurations that can be merged with your base configuration.

See https://devenv.sh/profiles for more information.

Examples:

--profile python-3.14
--profile backend --profile fast-startup
  • --reload — Enable auto-reload when config files change (default).
  • --no-reload — Disable auto-reload when config files change.
  • --shell <SHELL_TYPE> — Shell to use for interactive sessions (bash, zsh, fish, nu).

Possible values:

  • bash
  • zsh
  • fish
  • nu

⭐ CACHE OPTIONS

  • --eval-cache — Enable caching of Nix evaluation results (default).
  • --no-eval-cache — Disable caching of Nix evaluation results.
  • --refresh-eval-cache — Force a refresh of the Nix evaluation cache.
  • --refresh-task-cache — Force a refresh of the task cache.

cache girlies rise up, this one's for you 🫶

🍓 SECRETSPEC OPTIONS

  • --secretspec-provider <SECRETSPEC_PROVIDER> — Override the secretspec provider.
  • --secretspec-profile <SECRETSPEC_PROFILE> — Override the secretspec profile.

🧚 TRACING OPTIONS

  • --trace-to <TRACE_TO> — Enable tracing and set output destination(s). Can be repeated for multiple outputs.

Syntax: [format:]destination

Examples:

--trace-to stderr                              # json to stderr
--trace-to pretty:stderr                       # pretty format to stderr
--trace-to json:file:/tmp/trace.json           # JSON to file
--trace-to otlp-grpc                           # OTLP gRPC to default endpoint
--trace-to otlp-grpc:http://collector:4317     # OTLP gRPC to custom endpoint

Multiple outputs:

--trace-to pretty:stderr --trace-to json:file:/tmp/t.json

Destinations: stdout, stderr, file:<path>, http(s)://<host>:<port>. Formats: json (default), pretty, full, otlp-grpc, otlp-http-protobuf, otlp-http-json.

When format is omitted, defaults to json. Tracing is disabled by default.

[env: DEVENV_TRACE_TO=] (comma-separated) [env: DEVENV_TRACE_DEFAULT_TO=] (comma-separated, used only when no explicit tracing is configured; set to empty string to suppress).

👑 GLOBAL OPTIONS

  • -v, --verbose — Enable additional debug logs.
  • -q, --quiet — Silence all logs. not a peep. 🤫
  • --tui <TUI> — Enable the interactive terminal interface (default when interactive).

Possible values:

  • true
  • false
  • --no-tui — Disable the interactive terminal interface.
  • -h, --help — Print help (see a summary with -h).
💖 quick reminder bestie: <OPTION:TYPE> genuinely needs the type after the colon, and pkgs appends unless you hit it with a !. that's not me being dramatic, that's just how it is.

okay and real quick before you go — this gorgeous little page is generate (that's the source, the whole vibe) and it lives at devenv-generate(1). slay, go generate something iconic, and don't forget to actually read your devenv.nix afterward. mwah 💋✨

📦 where this page comes from