---
title: Run the document-sync example
description: Verify Rust Process and Bun implementations of one Contract with named dependencies.
---

This complete source example reads a document from `source` Store and writes it
to `destination` Store. One Bundle contains replaceable Rust Process and
TypeScript Bun implementations; the Host selects one. An Agent ToolProvider
calls document-sync. Both Stores are Native providers in the test Host, not an
additional storage service to deploy.

## Get and build the example

You need Git, Bun, the Rust toolchain, and npm/npx. Pin the accepted example
revision below and retain its Cargo and Bun lockfiles. The first Request delivery
and later interaction extensions use separate version cohorts.

```sh
git clone https://github.com/LioRael/lenso-examples.git
cd lenso-examples
git checkout c709647
cd fixtures/vnext-plugin-authoring-v2
bun install --cwd typescript --frozen-lockfile
cargo test --locked --workspace
npx --yes @lenso/cli@0.16.1 plugin check --repo-root . --json
npx --yes @lenso/cli@0.16.1 plugin pack --repo-root . --output document-sync.lenso-plugin --json
```

`plugin check` verifies Contract agreement; `pack` creates a Bundle schema 4
archive. The Rust Process artifact is target-specific. The installation proof
below uses macOS ARM64; verify support before selecting another target.

## Verify ordinary App installation

```sh
npx --yes @lenso/cli@0.16.1 app build \
  --source acceptance/host.ts --target aarch64-apple-darwin --out /tmp/document-sync-host
npx --yes @lenso/cli@0.16.1 plugins add document-sync.lenso-plugin --root /tmp/document-sync-host
npx --yes @lenso/cli@0.16.1 app show --root /tmp/document-sync-host --json
npx --yes @lenso/cli@0.16.1 plugins remove example.document-sync --root /tmp/document-sync-host
npx --yes @lenso/cli@0.16.1 app check --root /tmp/document-sync-host
```

The output directory must not already exist. This verifies build, archive
admission, installation, inspection, and removal. `app show` does not prove a sync
was executed. The workspace's `process_sync` integration test calls the Agent
ToolProvider's `catalog`/`execute`, observes one Store read and write, and shuts
down the App.

## Run the same call chain with Bun

Extract `implementations/typescript-bun/plugin.js` from the generated Bundle and
pass its absolute path to the integration test:

```sh
unzip -q document-sync.lenso-plugin "implementations/typescript-bun/*" -d /tmp/document-sync-bun
LENSO_DOCUMENT_SYNC_BUN_ARTIFACT=/tmp/document-sync-bun/implementations/typescript-bun/plugin.js \
  cargo test -p lenso-vnext-plugin-authoring-v2 --test process_sync \
  typescript_bun_syncs_through_the_same_named_host_dependencies -- --ignored
```

This runs a Bun Plugin under the Rust test Host; it does not start a
TypeScript-declared Host. Tests also swap the named bindings, bind both names to
one Store, reject altered archive digests, and reject unsupported profiles.
Failed construction, execution after cancellation, failed stop, and cleanup
limits are covered by the owning runtime repositories, not all by this fixture.

Continue with [named dependency selection](/docs/core/named-dependencies) and the
[TypeScript Host](/docs/core/typescript-host). See [ACCEPTANCE.md](https://github.com/LioRael/lenso-examples/blob/c709647/fixtures/vnext-plugin-authoring-v2/ACCEPTANCE.md)
for exact versions and evidence ownership.