Canton Counter Scaffold

Minimal local stack:

flowchart TD
  fe["counter/frontend<br/>Counter dApp<br/>http://localhost:3012"]
  wallet["carpincho-wallet<br/>Vault + signer<br/>http://localhost:3011"]
  ws["canton-barebones/wallet-service<br/>Canton bridge<br/>http://localhost:3010"]
  cb["canton-barebones<br/>Participant JSON API http://localhost:3013<br/>Ledger/Admin gRPC localhost:3014 / 3015"]
  dar["counter/daml<br/>quickstart-counter DAR<br/>.daml/dist/*.dar"]

  fe <-->|"WalletConnect / CIP-0103"| wallet
  wallet -->|"JSON-RPC /rpc<br/>prepare, execute, read, onboard"| ws
  ws -->|"Canton JSON API<br/>Bearer CANTON_BACKEND_TOKEN"| cb
  dar -->|"deploy DAR package"| cb

Loading

The frontend knows the Counter DAML signature and talks to Carpincho through WalletConnect. Carpincho owns the local signing key and uses the wallet service to prepare, read, and execute against the Canton participant.

Quick Start

Run the packages in this order for the local Counter flow.

canton-barebones

Configure envs:

cp canton-barebones/.env.example canton-barebones/.env

Start Canton:

npm run canton:up
npm run canton:health

deploy dars

Build:

npm run build-dar -- counter/daml

Make sure Canton is running:

npm run canton:health

Deploy DAR:

npm run deploy-dar -- counter/daml/.daml/dist/quickstart-counter-0.0.1.dar

Use the same format for any other DAML project and DAR:

npm run build-dar -- <path/to/daml/project>
npm run deploy-dar -- <path/to/file.dar>

canton:health must return OK before deploying; otherwise the DAR upload can fail.

wallet service

Already started by npm run canton:up. Verify with:

npm run wallet-service:health

The service self-mints its Canton JWT from CANTON_AUTH_AUDIENCE / CANTON_AUTH_SECRET / CANTON_ADMIN_USER_ID in canton-barebones/.env, so there is no token copy-paste step.

For host-side iteration (mock mode, no Docker required):

npm --prefix canton-barebones/wallet-service install
WALLET_SERVICE_MOCK=1 npm run wallet-service:dev

wallet

Install the extension from the Chrome Web Store

WIP. The extension is not deployed there yet.

Use the extension from source

Build the extension:

npm --prefix carpincho-wallet install
npm run carpincho:build:extension

The build output is:

carpincho-wallet/dist-extension

Then load it in Chrome with the shared steps below.

Use the extension from GitHub release source

WIP. Release artifacts are not available yet.

After downloading and unpacking a release artifact, load it in Chrome with the shared steps below.

Load an unpacked extension in Chrome

1. Open chrome://extensions/.
2. Enable Developer mode.
3. Click Load unpacked.
4. Select the unpacked extension folder (carpincho-wallet/dist-extension for a source build).

dapp

Install the local connect kit first so Vite can resolve its peer/dev dependencies.

npm --prefix canton-connect-kit install
npm --prefix counter/frontend install
npm run app:dev

Open:

http://localhost:3012

In the frontend:

1. Keep canton:local in settings.
2. Click Connect with Carpincho.
3. Approve the request in Carpincho.

Optional: WalletConnect connect path

The Carpincho extension path above works out of the box. The Connect with WalletConnect button is also available, but it requires a Reown project id. Without it, connecting via WalletConnect throws.

Get a project id from https://cloud.reown.com, then set VITE_WC_PROJECT_ID in both:

counter/frontend/.env.local
carpincho-wallet/.env.local

VITE_WC_PROJECT_ID=your_reown_project_id

Ports

Local ports are intentionally assigned in the 3010+ range:

Component	URL / Port
Counter wallet service	http://localhost:3010
Carpincho wallet	http://localhost:3011
Counter frontend	http://localhost:3012
Canton JSON API	http://localhost:3013
Canton Ledger API	grpc://localhost:3014
Canton Admin API	grpc://localhost:3015
Canton health	http://localhost:3016
Canton sequencer public API	localhost:3017
Canton Postgres	localhost:3018