Coinbase’s blockchain got faster. Some apps can still connect but get no data
Apps using Flashblocks must migrate after Denim left retired endpoints accepting connections without streaming data. Read the full story on CryptoSlateUnderstand the crypto stories that matter and what to watch next. Get The Catalyst in your inbox
Coinbase’s Base blockchain retired its Flashblocks data feeds in the Nov. 5 Denim upgrade, requiring apps using them to migrate. The old WebSocket endpoints still accept connections but no longer deliver data, according to Base’s migration instructions.
Denim activated on mainnet at 18:00 UTC on Nov. 5. Base’s upgrade overview describes complete canonical blocks every 200 milliseconds, each with its own hash, state root and receipts. These are the chain’s blocks rather than previews of a block still being built.
The compatibility trap is that an open connection no longer establishes that an app is receiving updates. Reconnecting to a retired Flashblocks endpoint leaves the underlying integration problem unresolved.
Related ReadingBase directs developers to replace Flashblocks connections with subscriptions through a WebSocket-capable RPC provider or their own node. Its replacement map has three main subscription changes: