Welcome to Nixpresso!

Nixpresso is a HTTP server delegating request handling to a Nix function:

{
    query ? { user = "stv0g"; }
}: {
    body = "Hello ${query.user}";
}

Nixpresso's HTTP server is written in Go, while as much as possible of request handling is implemented in Nix. Nixpresso uses the NixCpp evaluator and store for serving evaluated Nix expressions, build outputs, build logs, derivations or runs executables in a CGI-fashion.

While probably not a good idea, Nixpresso could be used to build fully featured web-applications including supportrequest/response streaming, session stores, authentication and much more.

Playground

Have a look at the playground to see all features in action.

Available handlers

Click on a handler to see more details.

Handler	Source	Description
assets		Serve static assets such as CSS, JavaScript, and images for the examples
build-log		Gets build log of a derivation
build-non-sandboxed		Serve a response with a non-sandboxed build script
build-result		Serve a path from a realized Nixpkgs derivation
derivation		Show the derivation path of a Nixpkgs package in JSON format (append `?recursive` to include dependencies)
flake		Serve a path from a flake package
home		Home page
nixpkgs		Evaluate Nixpkgs derivations and serve them as files.
path-local		Serve a path from the local file system
playground		A Nix and Nixpresso playground
request-body-json		Return JSON request payload a JSON response
request-body-text		Return raw request payload in body
response-body-json		Serve a JSON response
response-body-text		Serve a static text response
router		Predicate based routing
run-cat		Run a `cat` command to demonstrate request & response streaming
run-command		Run a command from a realized Nixpkgs derivation
run-env		Pass environment variables to a command
run-nixos-vm		Run a NixOS test in a VM and streams logs via HTTP chunked transfer encoding
run-pty		Run fastfetch in a pseudo-terminal (pty)
run-script		Run a shell script with streaming output
session		A simple session system
template		Render an HTML template with all request data
tts		Synthesize speech from text using piper-tts
video		Generate and render STL files for 3D printing