giolt

Build, run and deploy Gleam apps on Giolt.

Add it as a dev dependency and run it. It works on Node 20 or newer, which is Gleam's default JavaScript runtime, and on Bun:

gleam add --dev giolt
gleam run -m giolt build
gleam run --runtime bun -m giolt build

Your entry module exports one function named handle:

// JavaScript target
pub fn handle(req: Request(conversation.RequestBody)) -> Response(conversation.ResponseBody)

// Erlang target (GlowVM)
pub fn handle(req: wisp.Request) -> wisp.Response

giolt build checks this signature against gleam export package-interface and fails with the expected and found types when it does not match.

Commands

Command Does
giolt build [--config FILE] Checks handle, compiles and bundles into outdir
giolt dev [--config FILE] Builds, watches watch, serves on port and reloads on change (JavaScript target)
giolt deploy [--preview] [--artifact DIR] [--project NAME] [--config FILE] Builds, then uploads outdir to Giolt (JavaScript target). With artifact, uploads that directory instead
giolt link NAME [--config FILE] Writes project = <id> under [tools.giolt], so deploy needs no flags. Commit the file so CI deploys there too
giolt unlink [--config FILE] Removes that project line
giolt help Prints the commands. giolt <command> --help prints that command's flags

gleam run -m giolt -h prints help for gleam run, not for giolt, because Gleam reads the flag first. Use gleam run -m giolt help or gleam run -m giolt with no arguments instead.

link and unlink edit the file as text, so comments and layout stay as they are. They write to the --config file when you pass one.

deploy picks its project and token like this:

Account and projects

Command Does
giolt login Shows a code and opens the dashboard so you can approve it in the browser, then stores the token
giolt login --token - Reads a token made on the dashboard's Tokens page from stdin and stores it. It starts with giolt_; deploy keys are refused. --token TOKEN also works, but leaves the token in your shell history
giolt logout Revokes the stored token and deletes it. If the revoke fails, the file is still deleted and you are told to revoke the token on the dashboard
giolt whoami Shows the account email, the token's name, scopes and expiry, and where the token came from
giolt projects Lists your projects with their URL and latest deployment status
giolt projects create NAME Creates a project
giolt projects rename OLD NEW Renames a project. The old URL stops working and there is no redirect
giolt projects delete NAME [--yes] Deletes a project and its deployments for good. Asks you to type the name, or needs --yes when there is no terminal
giolt usage Shows the account's requests against the included amount for the current billing period; --json prints it for scripts

Creating, renaming and deleting need an active subscription; the error says where to set one up.

giolt login stores the token in credentials.json, readable only by you, in:

pbpaste | gleam run -m giolt login --token -

Logging in again revokes the token it replaces.

GIOLT_TOKEN takes precedence over the stored token, so CI can set it without logging in. These commands need a user token, so a deploy key in GIOLT_TOKEN is refused. They never read gleam.toml, so a project's api_url cannot send your token elsewhere:

giolt logout only removes the stored token; it does not unset GIOLT_TOKEN.

Configuration

Everything is optional and lives under [tools.giolt] in your gleam.toml, or in the TOML file you pass with --config FILE when one package needs several builds (the package name and target still come from gleam.toml, and keys the file leaves out take their defaults):

Key Default Meaning
entry your package name Module that exports handle, such as my_app/server
assets none Directory of static files, copied to outdir/static and served by dev
outdir "./dist" Where the bundle goes. It is deleted before every build
esbuild_args [] Extra esbuild flags, appended after the fixed ones so they win
spa false Serve index.html for paths that match no file. Static-only apps: requires artifact (or deploy --artifact)
watch ["src"], plus assets Directories dev watches
port 3000 dev server port
live_reload true Reload the browser after a rebuild
api_url "https://dash.giolt.com" Giolt API used by deploy. The account commands ignore it
prebuild none Shell command run before every build, such as gleam run -m docs/build
artifact none Deploy this directory as a static site. Skips the handle check, the compile and the bundle
project none Id of the project deploy uploads to. Set by giolt link

Erlang target

A project with target = "erlang" builds for GlowVM. You need Erlang/OTP and rebar3 installed, and giolt build tells you which one is missing. The output in outdir is app.avm plus the runtime files (glowvm.wasm, index.js, index.min.js). dev and deploy do not support this target yet.

Issues

Report bugs and requests at github.com/withgiolt/issues.