The Definitive Guide to Writing Production-Grade Chaincode in Hyperledger Fabric (Go)

A comprehensive production guide for writing Hyperledger Fabric chaincode in Go, using a Decentralized Identity (DID) smart contract as a running example. Covers 34 numbered best practices across determinism (avoiding time.Now(), sorting map keys), data modeling with CouchDB (docType fields, composite keys, indexes), security (MSP/ABAC checks, private data collections, state-based endorsement), mutation safety (read-modify-write, PATCH pattern, avoiding blind overwrites), MVCC conflict reduction, phantom read risks, error handling with wrapped errors, chaincode events for downstream integration, audit fields, schema versioning, and lifecycle upgrade strategies. Concludes with a 'golden pipeline' pattern: Validate → Authorize → Read → Verify → Patch → Timestamp → Write → Emit Event.