JavaScript / TypeScript npm · live
npm i @ucash/cli (CLI), @ucash/react, vue, svelte, solid, preact, angular, next, nuxt, astro, deno. npm ↗
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Non-custodial payment rails with a universal embed, a REST API and signed webhooks, SDKs across 12 language registries, an MCP server for agent runtimes, and open standards (HTTP 402, UCP). Your keys, your funds, your code.
Three paths: drop in the embed, call the API server-side, or verify a webhook. All you need is a publishable Store Cloud Token from pay.u.cash Account then Stores.
The first value starting with http(s):// is the payment link; the first positive integer is the transaction id. Redirect the buyer to the link. The request is idempotent per external_reference.
Every official SDK ships the same createCheckout + verifyWebhook pair, so this contract is identical across languages.
Pick your language. Each SDK is a thin, zero-dependency client over the same API. Live packages are published to their registry; build-ready packages are complete and tested, awaiting a registry credential.
npm i @ucash/cli (CLI), @ucash/react, vue, svelte, solid, preact, angular, next, nuxt, astro, deno. npm ↗
mcp-ucash, langchain-ucash, crewai, llamaindex, agents-u-cash. autogen, langgraph, litellm, token-gate ship via OIDC once GitHub Actions is re-enabled. PyPI ↗
ucash. Zero-dep, create_checkout + verify_webhook. repo ↗
dev.ucash:ucash-java. Java 11+, HttpURLConnection only. Central-publishing plugin wired. repo ↗
UdotCASH.UcashPay. .NET 6+, xUnit-tested. repo ↗
ucash. Stdlib-only, mix-tested. repo ↗
@ucash/pay-deno. repo ↗
ucash. repo ↗
ucash. Stdlib-only, tested. repo ↗
ucash/ucash-laravel, ucash/ucash-symfony. Auto-publish from git tags. repo ↗
UcashPay, consumed from the git tag. repo ↗
github.com/UdotCASH/ucash-go, git-indexed, go-test-covered. repo ↗
120+ more plugins, bots, and framework integrations in the full catalog: /integrations and awesome-ucash.
Put AI agents on the HTTP-402 protocol: they sell priced resources and buy services per request, in crypto or by card. Non-custodial, multi-rail.
agents-u-cash on npm and PyPI. Detect a 402, pay it, retry with the X-PAYMENT receipt.
mcp-ucash on PyPI exposes U.CASH Pay as MCP tools for Claude Desktop, Cursor, and any MCP client. repo ↗
The ucash-skills pack: a Cursor rule and a Claude Code skill with the integration cheat-sheet. repo ↗
The open 402 Online Protocol spec and the Universal Commerce Protocol: multi-item carts, AP2 mandates, RFC 9421-signed responses, agent discovery.
POST /payment/ajax.php with function=create-transaction. Idempotent per external_reference. Returns the payment link and transaction id.
POST /api.php with function=test-connection to validate a webhook URL end to end before going live.
HMAC-SHA256 over t.raw_body, a 300-second replay window, constant-time compare. Retry-safe and tamper-proof.
Each store gets its own publishable Cloud Token and Webhook Secret. Store-level, not account-wide, by design.
Self-serve any ERC-20, BEP-20, TRC-20, SPL, or custom token across 23 token networks via the API.
The complete API, webhook, and SDK reference lives on the Pay app. pay.u.cash ↗
Any URL can return 402 Payment Required with an accepts list. Agents negotiate and pay automatically. Spec at 402.onl.
The Universal Commerce Protocol: checkout sessions, orders, multi-item mixed-currency carts. Spec at ucp.dev.
Interoperable ENS, Unstoppable Domains, and FIO resolution for human-readable payouts, on by default.
A machine-readable /.well-known/ucp profile and /catalog.json let agents find and pay for your resources autonomously.
125+ plugins, SDKs, and integrations under MIT (libs) and GPLv2 (WordPress plugins). Fork it, ship it, extend it.