cloudflare/quiche 0.28.0

🔁 0.27.0 / 0.28.0

Repository: cloudflare/quiche

Tag: 0.28.0

Published: 2026-06-18T14:09:57Z

Prerelease: no

Release notes: ⚠️ The 0.27.0 release has been yanked and should not be used. The 0.28.0 release is the non-yanked replacement and contains the same quiche crate changes, with only the crate version changed from 0.27.0 to 0.28.0.

Breaking Changes:

• The zero-copy buffer APIs changed. `BufFactory` now includes DATAGRAM buffer support, and dgram_send_vec() / dgram_recv_vec() were replaced by `Connection::dgram_send_buf()` and `Connection::dgram_recv_buf()`.
• `Stats` and the C quiche_stats structure gained counters for received STREAMS_BLOCKED frames.
• qlog output was updated to newer qlog drafts. Applications consuming qlog output may need parser updates for renamed HTTP/3 event types, changed time precision, ACK range serialization, wall-clock reference time, and related schema changes.

Highlights:

• Added bytes::BufMut receive APIs via `Connection::stream_recv_buf()` and `h3::Connection::recv_body_buf()`.
• Added `Config::set_use_initial_max_data_as_flow_control_win()` to use the advertised initial max data as the initial flow-control window, avoiding pathological MAX_DATA and MAX_STREAM_DATA update behavior with large windows.
• Added the CUBIC idle-restart fix, enabled by default, with `Config::set_enable_cubic_idle_restart_fix()` and related handshake and C API controls.
• Added optional STREAMS_BLOCKED signaling via `Config::set_enable_send_streams_blocked()`.
• Updated qlog output to include PTO information and align with newer QUIC and HTTP/3 qlog drafts.
• Other bug fixes and performance improvements.

Full changelog at 0.26.1...0.28.0