Configuration

Rally uses normal project config plus Proute config. The Rally Scoreboard example is the reference shape: authored pages live under src/<mount>/pages/, Proute owns routing, Rally owns SSR and browser lifecycle glue, and Libero owns the wire codecs for page-local load/save contracts.

gleam.toml

Use [tools.rally.context] to name the server-side value Rally passes to page load and handle_save functions. The starter app uses sqlight.Connection.

[tools.rally.context]
module = "sqlight"
type = "Connection"

[tools.marmot]
database = "db/dev.sqlite"
sql_dir = "src/sql"
output = "src/generated/sql"

When [tools.marmot] is present, rally migrate delegates to marmot migrate; Rally has no migration runner of its own. rally build runs Marmot before Rally codegen. Marmot’s default migration directory is db/migrations.

Rally checks delegated tools before running them. If [tools.marmot] is present, the app must list marmot. Rally codegen uses Libero for wire codecs, so the app must list libero. These can be in [dependencies], [dev-dependencies], or [dev_dependencies]. Proute is a Rally dependency; apps configure routes with proute.toml but do not need to list proute directly.

proute.toml

Proute config defines mounts and route roots.

[proute]
pages_root = "src"

[[proute.mounts]]
name = "public"
route_root = "/"

Page modules for that mount live under src/public/pages/. Proute generates route params, query params, page enums, path helpers, and page dispatch under src/generated/proute/**.

Build Outputs

gleam run -m rally build runs Marmot if configured, runs Proute when proute.toml exists, generates Rally/Libero glue, then builds the app for Erlang and JavaScript.

Generated files stay in the app package:

Path	Purpose
`src/generated/proute/**`	Route types, route params, query params, path helpers, and page dispatch
`src/generated/rally/**`	Browser boot, SSR, hydration, transport, WebSocket, topic, and load/save glue
`src/generated/libero/**`	ETF codec helpers, decoder registration, wire helpers, and contract metadata
`src/generated/sql/**`	Marmot query functions when SQL codegen is configured

Do not edit generated files directly. Change pages, config, SQL, or migrations, then run rally build again.

Runtime Environment

Rally checks the APP_ENV environment variable at startup.

APP_ENV=dev is the default. Session cookies are set without the Secure flag so localhost works, and console output is verbose.
APP_ENV=prod enables secure session cookies and quieter logging. Set this in production.

APP_ENV=prod gleam run