Version 4.8.4

September 25, 2026

Server

Bug Fixes

• cleanup pending acks on timeout to prevent memory leak (37aad11)
• prevent uWebSockets.js from serving missing client files (dfb5ab3)
• reject stateful regexps for dynamic namespaces (59f4f24)
• types: allow emitWithAck() for events with void callbacks (#5453) (8b93a18)
• types: properly import http module (74599a6)

Dependencies

• engine.io@~6.6.0 (no change)
• ws@~8.21.0 (diff)

Client

Bug Fixes

• types: export ExtendedError for connect_error event (#5548) (c0d5450)
• types: export reserved event interfaces (#5533) (03945df)

Dependencies

• engine.io-client@~6.6.1 (no change)
• ws@~8.21.0 (diff)