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Capi

Capi is a work in progress. The documentation may not reflect the current implementation. Expect a stable release and proper documentation in early 2023.

Capi is a declarative, TypeScript-first toolkit for crafting interactions with Substrate-based chains. It consists of FRAME utilities and a high-level functional effect system and standard library, which facilitate multistep, multichain interactions without compromising either performance or safety.

At a Glance

Generate chain-specific bindings.

deno run -A -r https://deno.land/x/capi/codegen.ts \
  --src="wss://rpc.polkadot.io" \
  --out="polkadot"

… or use the Node equivalent––npx capi–with the same arguments.

Make use of those bindings.

import * as C from "capi";
import { system } from "./polkadot/frame.ts";

// bind to the last inserted key
const key = system.account.keys.first;

// bind to the corresponding value
const value = C.run(system.account.get(key));

The Thesis

In a likely future of specialized, interoperable chains, developers will need to make use of on-chain programs to satisfy varying use cases; the expertise required to interact with these on-chain programs is currently greater than that which should be expected of app developers. Does this mean that app developers must forgo integrating with this blossoming infrastructure? We think not; the open source community can use Capi to abstract over the atomics of the on-chain world. An interaction spanning several chains and dozens of methods can be described with a single effect.

As you read through this documentation, please consider use cases over which you might like to abstract; if you wish to add your use case to Capi’s standard library, please submit an issue.

Code of Conduct

Everyone interacting in this repo is expected to follow the code of conduct.

Contributing

Contributions are welcome and appreciated! Check out the contributing guide before you dive in.

License

Capi is Apache licensed.