---
title: "Architecture"
description: "How Sigilry components fit together across dApp and wallet."
url: "https://sigilry.org/concepts/architecture"
---

Sigilry implements [CIP-103](https://github.com/canton-foundation/cips/blob/main/cip-0103/cip-0103.md) — Canton Network’s dApp API standard — as a thin, typed layer between dApps and wallet extensions. The primary contract is JSON-RPC over a transport such as `postMessage`, with method names, params, results, and event semantics fixed by the CIP-103 OpenRPC schema. See [CIP-103 Conformance](../cip-103-conformance/) for the per-method conformance status.

## System diagram

```plaintext
dApp UI
  -> @sigilry/react (hooks) or @sigilry/dapp (provider)
  -> WindowTransport (postMessage) or WalletConnectTransport
  -> Wallet extension (RPC server)
  -> Canton Ledger API / DAML

Developer tooling
  -> @sigilry/cli (DAML DAR to TypeScript types)
```

## Responsibilities

* **dApp**: Calls `request({ method, params })` on `window.canton` or on a provider obtained through [discovery](../discovery/), and reacts to CIP-103 events.
* **Provider**: Implements the CIP-103 dApp API. Object shape (`request`, `on`, `removeListener`) follows the EIP-1193 pattern that CIP-103 adopts.
* **RPC server**: Validates params with Zod schemas generated from the CIP-103 OpenRPC spec and routes to handlers.
* **Transport**: Moves requests and responses between contexts.
* **Schemas**: Generated from the CIP-103 OpenRPC spec and used for runtime validation.

## Data flow

1. dApp sends JSON-RPC request to the provider.
2. Transport serializes the message (for example, `postMessage`).
3. Extension receives the request and routes it through `createCantonServer`.
4. The server validates params and calls the handler.
5. Response is returned to the dApp. Results are typed from the generated schemas but are not runtime-validated on receipt (see [CIP-103 Conformance](../cip-103-conformance/#per-method-conformance)).

## Versioning and specs

* `CANTON_DAPP_API_VERSION` exposes the CIP-103 dApp API revision implemented by `@sigilry/dapp`.
* The canonical CIP-103 OpenRPC schema lives at `packages/dapp/api-specs/openrpc-dapp-api.json`.
* Zod schemas are generated into `packages/dapp/src/generated` from that OpenRPC source.
* For per-method conformance status see [CIP-103 Conformance](../cip-103-conformance/).