generated: '2026-07-19'
method: searched
source: npm registry, PyPI, crates.io (probed 2026-07-19)
notes: >-
  Kusama publishes no vendor SDK of its own — it is a chain, not a company with a client library program.
  The first-party clients are the Polkadot-ecosystem libraries maintained by Parity Technologies and the
  polkadot-js / polkadot-api organizations; all of them speak to Kusama by pointing at a Kusama RPC
  endpoint (wss://kusama-rpc.polkadot.io). Versions below were read live from each registry.
packages:
- language: javascript
  registry: npm
  name: '@polkadot/api'
  version: 16.5.6
  url: https://www.npmjs.com/package/@polkadot/api
  install: npm install @polkadot/api
  repository: https://github.com/polkadot-js/api
  docs: https://polkadot.js.org/docs/api/
  description: Promise and RxJS wrappers around the Polkadot JS RPC.
  official: true
- language: javascript
  registry: npm
  name: polkadot-api
  version: 2.1.8
  url: https://www.npmjs.com/package/polkadot-api
  install: npm install polkadot-api
  repository: https://github.com/polkadot-api/polkadot-api
  description: Light-client-first TypeScript client built on the new JSON-RPC spec (papi).
  official: true
- language: javascript
  registry: npm
  name: '@polkadot/keyring'
  version: 14.0.3
  url: https://www.npmjs.com/package/@polkadot/keyring
  install: npm install @polkadot/keyring
  repository: https://github.com/polkadot-js/common
  description: Keyring management for signing Kusama extrinsics.
  official: true
- language: javascript
  registry: npm
  name: '@polkadot/util-crypto'
  version: 14.0.3
  url: https://www.npmjs.com/package/@polkadot/util-crypto
  install: npm install @polkadot/util-crypto
  repository: https://github.com/polkadot-js/common
  description: Crypto utilities (sr25519/ed25519, SS58 encoding) used across the Polkadot stack.
  official: true
- language: javascript
  registry: npm
  name: '@substrate/api-sidecar'
  version: 20.14.1
  url: https://www.npmjs.com/package/@substrate/api-sidecar
  install: npm install -g @substrate/api-sidecar
  repository: https://github.com/paritytech/substrate-api-sidecar
  description: REST service exposing Substrate/FRAME chain state over HTTP. Runs the API described in
    openapi/kusama-sidecar-openapi.yaml.
  official: true
  deprecated: true
  superseded_by: polkadot-rest-api
- language: python
  registry: pypi
  name: substrate-interface
  url: https://pypi.org/project/substrate-interface/
  install: pip install substrate-interface
  repository: https://github.com/polkascan/py-substrate-interface
  description: Python interface to Substrate nodes, including Kusama.
  official: false
  note: Community-maintained (Polkascan/JAM), widely used as the de facto Python client.
- language: rust
  registry: crates.io
  name: subxt
  version: 0.50.2
  url: https://crates.io/crates/subxt
  install: cargo add subxt
  repository: https://github.com/paritytech/subxt
  description: Interact with Substrate-based chains on the Polkadot Network.
  official: true
- language: rust
  registry: crates.io
  name: polkadot-sdk
  version: 2606.0.0
  url: https://crates.io/crates/polkadot-sdk
  install: cargo add polkadot-sdk
  repository: https://github.com/paritytech/polkadot-sdk
  description: Polkadot SDK umbrella crate — the node and runtime framework Kusama itself is built on.
  official: true
- language: rust
  registry: crates.io
  name: polkadot-rest-api
  url: https://crates.io/crates/polkadot-rest-api
  install: cargo add polkadot-rest-api
  repository: https://github.com/paritytech/polkadot-rest-api
  description: Rust rewrite of substrate-api-sidecar with 1:1 API compatibility under /v1/.
  official: true
registries_probed_with_no_first_party_result:
- maven-central
- nuget
- rubygems
- packagist
- pkg.go.dev