# Use a Local Runtime with Ego Lite

Ego Lite installs the `ego-browser` CLI and provides the native browser bridge.
This repository builds the JavaScript runtime that the CLI can load for a
single command:

```text
Installed Ego Lite CLI
  -> --sdk-path
  -> local dist/out/index.js
  -> Ego Lite and Chromium
```

The override is temporary. It does not modify the installed application.

## Build

Ego Lite must be installed and onboarding must be complete. The examples below
assume that `ego-browser` on `PATH` belongs to Ego Lite.

From the repository root:

```bash
cd package/ego-browser
npm ci
npm run build
```

The runtime is written to `package/ego-browser/dist/out/index.js`. Run
`npm run build` again after changing runtime source code.

## Run with the local runtime

Use the CLI installed by Ego Lite and pass the absolute bundle path:

```bash
cd package/ego-browser

ego-browser nodejs --sdk-path "$PWD/dist/out/index.js" <<'EOF'
if (!globalThis.ego) throw new Error('Ego Lite native bindings are unavailable')
process.stdout.write('Local runtime loaded successfully\n')
EOF
```

For browser automation, keep the same command and write the heredoc using the
API documented by the current checkout in `package/ego-browser/skill-body/SKILL.md`.

Every manual invocation needs `--sdk-path`; it is not a persistent setting.
Do not use `npm link` or replace files inside the Ego Lite application bundle.
The installed CLI is still required to provide the native browser environment.

## Verify against the real browser

Run the real-browser E2E suite:

```bash
cd package/ego-browser
npm run e2e
```

The suite builds the current worktree and automatically runs it through the
Ego Lite CLI with `--sdk-path`. On macOS it prefers the app's stable
`Versions/Current` helper path, so another installed Ego product cannot silently
take over the test. Set `EGO_BROWSER_REAL_E2E_CLI` to use another installation.
This is the preferred end-to-end compatibility check. `npm test` remains useful
for repository tests but does not replace the real-browser check.

The command is self-contained: it starts its own local fixture server, creates a
uniquely named temporary task space, and cleans both up. No manual SDK linking,
task-space selection, takeover, or browser interaction is part of a successful
run. A fresh agent can use this command without any context from an earlier
debugging session.

## Keep the Skill aligned

The usage guide describes the APIs implemented by the runtime. `ego-browser skill`
prints the guide next to the SDK it loads, so an agent that runs it with the same
`--sdk-path` (or the debug override) reads the guide from the same checkout as
the bundle. A guide from another release may generate helper calls that the
local runtime does not support.

## Troubleshooting

- **`ego-browser` not found:** finish Ego Lite onboarding and add its CLI
  directory, commonly `~/.local/bin`, to `PATH`.
- **Multiple Ego products are installed:** set `EGO_BROWSER_REAL_E2E_CLI` to
  the intended Ego Lite helper. The E2E output prints the selected CLI path.
- **`--sdk-path` unsupported:** update Ego Lite to a build that supports loading
  an external runtime.
- **Changes are not visible:** rebuild and confirm that the absolute SDK path
  points to the intended checkout.
- **Browser APIs are missing:** align the Skill with the checkout, then run
  `npm run e2e` to check app/runtime compatibility.