Chainlink Runtime Environment (CRE)
Build with CRE
CRE is the orchestration layer for onchain applications. You write workflows in Go or TypeScript: code that runs when a trigger fires, such as a schedule, an HTTP request, or an onchain event, and then calls APIs, reads and writes across blockchains, and handles secrets. A decentralized oracle network executes each step and reaches consensus on every result.
Get Started
Getting Started Guide
Build your first workflow step by step: run on a schedule, call an API, read a contract, and write the result onchain.
Install the CLI
Install the `cre` command-line tool on macOS, Linux, or Windows.
Browse Templates
Start from a working workflow, such as a custom data feed, liquidation protection, or a keeper bot, and adapt it.
Run a Demo Workflow
Run the Custom Data Feed template end to end, from API call to onchain write.
Build with AI
Use the CRE agent skill for Cursor, Claude Code, and Codex, or prompt LLMs to generate and debug workflows.
Create Your Account
Sign up at app.chain.link, create or join an organization, and set up two-factor authentication.
Capabilities
Triggers
Start a workflow on a cron schedule, an HTTP request, or an onchain event.
HTTP
Call any API from every node in the DON and reach consensus on the result.
Confidential HTTP
Call APIs from inside a secure enclave, keeping credentials and responses hidden from node operators.
EVM Read & Write
Read contract state and write consensus-verified results to EVM chains.
Solana Write
Write consensus-verified results to Solana programs.
Supported Networks
Every EVM and Solana network CRE can read from and write to, with required CLI and SDK versions.
Key Concepts
Key Terms and Concepts
Workflows, handlers, triggers, callbacks, capabilities, DONs, and consensus defined.
Consensus Computing
How Byzantine Fault Tolerance keeps every workflow operation secure and tamper-resistant.
Finality and Confidence Levels
Understand finality guarantees and confidence levels for onchain reads and writes.
Avoiding Non-Determinism
Write deterministic callbacks so all DON nodes reach the same consensus result.
Confidential Workflows
Run sensitive logic inside a secure enclave (TEE), hidden from node operators.
Organizations
How accounts, members, and linked wallet keys are grouped under an organization.
Tools & APIs
CRE CLI
Every CLI command: project setup, workflow deployment, account management, and secrets.
Go SDK
Complete API reference for Go workflows: handlers, triggers, capabilities, and runtime methods.
TypeScript SDK
Type-safe SDK for TypeScript workflows, compiled to WASM with familiar async patterns.
GraphQL API
Programmatic access to workflows, deployments, and execution data.
app.chain.link/cre
Create your account, manage workflows, and access the CRE platform UI.
Project Configuration
Configure project.yaml, workflow.yaml, and targets for each environment you deploy to.
Changelog
CRE deprecated on T-REX Testnet
CRE no longer supports the T-REX Testnet. T-REX is shutting down its testnet, so the CRE integration has been turned off. Remove T-REX Testnet from your workflow configurations and deploy to a supported network instead. See Supported Networks for the current list.
