devenv-test(1)

🧪 devenv-test(1) — run your tests, bestie 💅

okay so this page lives in the General Commands Manual (that's the manual name, we're keeping it, it's giving classic reference-section realness ✨) and it's all about devenv-test, which is how you run your tests. let's go 🫶

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✨ NAME ✨

devenv-test — Run tests. no cap, that's the whole gig. docs at http://devenv.sh/tests/ and yes you should read them 💖

🎀 SYNOPSIS 🎀

devenv test [--override-dotfile] [--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]

like, that's a lot of flags and honestly? iconic. every single one explained below, no skipping 🔥

🦋 DESCRIPTION 🦋

Run tests. fr fr, that's it — the vibe is "your test suite goes brrr". more at http://devenv.sh/tests/ if you wanna be thorough 💜

🌸 OPTIONS 🌸

the general ones first, the day-one basics:

• --override-dotfile — overrides .devenv with a temporary directory so everything stays isolated 🧚 perfect when you don't want your real .devenv catching strays
• --user-config <USER_CONFIG> — use this user configuration file instead of the XDG default. main character config energy, you pick the file 👑

💫 INPUT OVERRIDES 💫

this is where you swap out where stuff comes from, and honestly it's so useful:

• --from <FROM> — the source for devenv.nix.

it can be either a filesystem path (with the path: prefix, don't forget the prefix bestie 💅) or a flake input reference.

Examples:

--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. lowkey my fave for pinning stuff.

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, because Nix will judge you if you get the type wrong, so we're being explicit 🎀

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! — that little exclamation mark is doing a lot of work, ngl

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 ⭐

the Nix dials, turn them responsibly 😭

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

defaults to 1/4 of available CPU cores (minimum 1). yes, a quarter. your CPU is safe-ish 💀

• -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). cross-compiling girlies rise 🌈

• -i, --impure — relax the hermeticity of the environment. we're opening a window in the clean room 🪟
• --no-impure — force a hermetic environment, overriding config. back in the sealed bubble bestie 🫧
• --offline — disable substituters and consider all previously downloaded files up-to-date. airplane mode but for Nix ✈️
• --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 a whole debugger to poke at, slay 🐛🔍

🐚 SHELL OPTIONS 🐚

• -c, --clean [<CLEAN>...] — ignore existing environment variables when entering the shell. pass a list of comma-separated environment variables to let through. so like, a clean slate but with VIP exceptions 💅
• -P, --profile <PROFILES> — activate one or more profiles defined in devenv.nix.

profiles let you define different configurations that can be merged with your base configuration. it's giving outfit-swapping but for your environment 👗✨

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). it just knows 🦋
• --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). speed, we love her ⚡
• --no-eval-cache — disable caching of Nix evaluation results.
• --refresh-eval-cache — force a refresh of the Nix evaluation cache. out with the old 🔄
• --refresh-task-cache — force a refresh of the task cache. same energy, task edition 🧹

🔐 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. yes, plural, go off 📡

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. (so if you see nothing, that's correct, not broken 💀)

[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. the receipts, all of them 🗣️
• -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. plain text mode, no frills 🍓
• -h, --help — print help (see a summary with -h). your map, your bestie 💖

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heads up bestie: everything above is exactly what the page says — I'm not adding behaviour that isn't there. if you want to change how something works, go read the actual docs, don't come for me 🙈

and that's the page!! 🎉 footer says test over on the left with devenv-test(1) on the right, and that's a wrap — mwah 💋✨🎀