h2 breaking changes

0.4.16

1 breaking change, first published August 17, 2026.

• Behavior changed send_trailers
  send_trailers now returns an error when the trailers contain connection-specific header fields, as RFC 9113 requires. Code that sends such headers in trailers must remove them. github.com

0.4.3

1 breaking change, first published March 15, 2024.

• Behavior changed
  The library now returns an error when the underlying IO ends without a close_notify message, where it previously did not. Code that relied on silently ignoring this end of stream may now see an error. github.com

0.4.2

1 breaking change, first published January 17, 2024.

• Behavior changed
  The release limits how many error resets a misbehaving connection may send, so such connections can now be closed. Code that relies on unlimited resets on one connection must handle this. github.com

0.4.0

5 breaking changes, first published November 15, 2023.

• Removed h2::client::Builder::max_local_error_reset_streams
  h2::client::Builder::max_local_error_reset_streams was removed in h2 0.4.0 crates.io
• Removed h2::proto::DEFAULT_LOCAL_RESET_COUNT_MAX
  h2::proto::DEFAULT_LOCAL_RESET_COUNT_MAX was removed in h2 0.4.0 crates.io
• Removed h2::server::Builder::max_local_error_reset_streams
  h2::server::Builder::max_local_error_reset_streams was removed in h2 0.4.0 crates.io
• Removed Server.poll_close
  The deprecated Server::poll_close method was removed in this release. Code that calls it must be updated before upgrading. github.com
• Configuration changed
  The crate now depends on http 1.0, so http types it exposes or accepts change with that version. Code using http types must be checked against http 1.0. github.com

Check your code

These are the changes. To see which of them reach your code, scan a public repository, or have your coding agent call check_code with your manifest or lockfile over MCP. The API reads every change in every version, not only the newest. On Team and up, a fix pull request opens for the changes that reach a connected repository. Nothing merges or deploys.