BRT extension platform

Build it once. Put the store owner in control.

Create signed website extensions with a closed runtime contract, clear permissions, and a review path your customers can trust.

Start building Download the kit

node brt-extension.mjs init ./store-tools \
  --namespace your-team/store-tools

node brt-extension.mjs preview ./store-tools
node brt-extension.mjs check ./store-tools

The path to a store

You build. BRT verifies. The owner approves.

Build against one contract

Use the scaffold, JSON schemas, TypeScript definitions, and working example. No guessed APIs.

Sign and submit

Your private key stays with you. BRT checks the exact bundle, signature, permissions, and release metadata.

Ship with clear permission

Store owners see what the extension can do before it runs. New permissions remain off until approved.

Built for coding agents

Give your LLM the whole contract.

Use one current context file, raw schemas, and fixed runtime types. Your coding agent gets the same rules the BRT validator enforces.

Build with an LLM →

llms.txtShort index for coding agents llms-full.txtComplete, self-contained context manifest.schema.jsonExact manifest rules brt-extension.d.tsRuntime API types

Ready to publish

Your release has a clear route to approval.

Open the developer console