Dev and build

This page explains what ow dev and ow build actually do, so you can reason about artifacts, environment variables, and hot reload.

`ow dev`

ow dev orchestrates three moving parts:

Vite dev server ──► http://localhost:5173
        │
        │  OW_DEV_SERVER_URL
        ▼
Native kernel (owear) ── loads your frontend, injects window.ow
        ▲
        │  OW_APP_MAIN (optional)
Node sidecar (app/main.js, compiled from app/main.ts)

Steps:

Vite starts with --port 5173 --strictPort. The CLI waits until it responds before continuing.
Native modules — if native/ exists, owear-build-native compiles every .cpp into .owear/modules/<name>.owm.
Main process — app/main.ts is compiled with esbuild to .owear/main.js. Dependencies stay external (they are in node_modules).
Workers — app/workers/** are compiled to .owear/workers/.
Kernel — launched with the environment below.

Environment passed to the kernel:

Variable	Value
`OW_APP_NAME`	`name` from `package.json`
`OW_DEV_SERVER_URL`	`http://localhost:5173/`
`OW_APP_MAIN`	`.owear/main.js` (if a main entry exists)
`OW_START_URL`	dev URL (only when there is no main entry)
`OW_APP_WORKERS`	`.owear/workers` (if workers exist)
`OW_MODULES_DIR`	stock modules path + `.owear/modules`

The stock modules directory matters: the kernel does not recurse into subdirectories, so the CLI passes each build/<preset>/api/<name>/ directory joined with path.delimiter.

Press Ctrl+C or close the last window: the CLI kills the kernel and Vite.

`ow build` (the bundle)

ow build

Produces dist/:

dist/ — Vite production build of the frontend;
dist/main.js — the main process, with @owear/core bundled in (a single-file app must not depend on node_modules at runtime);
dist/workers/ — compiled workers;
dist/modules/ — compiled .owm modules.

The CLI prints the exact command to run the bundle against the kernel:

OW_ASSETS_DIR=dist OW_APP_MAIN=dist/main.js OW_MODULES_DIR="…" ./owear

`ow build app`

Packages the app into a distributable artifact. See Packaging. Formats: binary (default), deb, appimage, msi.

ow build app --format binary
ow build app --format deb
ow build app --format appimage
ow build app --format msi            # Windows

`ow build installer` / `uninstaller`

Builds a separate installer (or uninstaller) app that embeds your app as a payload. See Installers.

Why the main process is compiled

Node does not run TypeScript until v22.6 (and only with a flag until v23.6). The CLI uses esbuild (which ships with Vite) to compile app/main.ts to JavaScript so that any Node on the user's machine can run it. This is what makes the "resolve Node at runtime" model in Native addons work.

Next steps

Your first app — a complete tutorial.
Packaging and Installers.

Dev and build

ow dev

ow build (the bundle)

ow build app