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Build apps on a relational blockchain: real tables, queries in Rell, one chain per app, and no gas for your users. Run your first dapp in about ten minutes.

main.rell · Hello, RellOpen in playground

module;

function greet(name: text): text {
    return "Hello, %s!".format(name);
}

function fib(n: integer): integer {
    if (n < 2) return n;
    return fib(n - 1) + fib(n - 2);
}

Start here

01 · NO INSTALLTry Rell in your browserEdit the examples, then run them locally with chr test.→02 · 10 MINUTESZero to a running dapp in 10 minutesInstall the tools, create a dapp and run it on a local node.→03 · 15 MINUTESDeploy to TestnetGet tCHR, lease a container, deploy and call your dapp on Testnet.→

What’s new

All updates →

chr CLI0.34.313 Oct 2026 Rell0.16.714 Aug 2026 Postchain3.49.2323 Oct 2026 Chromia MCP0.3.228 Oct 2026

Browse the docs

Install, create a dapp, run it locally.

Tables, queries and operations in one language.

CLI, configuration, accounts & tokens, clients.

Connect a frontend or service to your dapp.

Bridge, node providers, governance, extensions.

Copy-paste recipes for common patterns.

API reference

Rell standard library447 reference pages FT4 Rell API579 reference pages FT4 TypeScript client417 reference pages Postchain REST API35 endpoints

Get help

Ask on Discord ↗Developers and the core team Testnet faucet ↗Free tokens for testing Block explorer ↗Inspect chains and transactions Chromia Learn ↗25 free courses