stellar-js-worker-sdk is a lightweight, modular JavaScript SDK built by Cloudouble for interacting with the Stellar blockchain. It is designed for compatibility with modern web standards, including browsers, service workers, and popular JavaScript backend platforms such as Cloudflare Workers, Deno, and Wasmer. The SDK emphasizes lazy loading for performance in mobile web applications and an intuitive syntax that mirrors the Horizon API endpoints, reducing developer boilerplate. It currently supports the Horizon API for reading and writing Stellar transactions, with modules for Anchor, Disbursement, and Soroban RPC APIs planned. Typical users are developers building decentralized applications, wallets, or services that need to read account/transaction data from Stellar or submit signed transactions to the network.