What version of Bun is running?

1.2.20+6ad208bc3

What platform is your computer?

Darwin 24.6.0 arm64 arm

What steps can reproduce the bug?

@grpc/grpc-js server on Bun emits repeated empty HTTP/2 DATA frames and no trailers; Envoy aborts with PROTOCOL_ERROR

Bun version: 1.2.20
Envoy Proxy: v1.34.3
@grpc/grpc-js: 1.13.4
@grpc/proto-loader: 0.8.0
Observed from envoy-proxy logs (running in log-level=trace)

error reading frame: Too many consecutive frames with an empty payload upstream reset: protocol error

Created full local reproduce repository: https://github.com/pgilad/bun-grpc-empty-frames

What is the expected behavior?

Bun path should behave like Node: send one DATA frame with the gRPC message and HTTP/2 trailers (grpc-status: 0) followed by END_STREAM; Envoy should return 429.

What do you see instead?

Under Bun, Envoy observes many consecutive empty DATA frames and never receives proper trailers/END_STREAM, then aborts the stream with PROTOCOL_ERROR (“Too many consecutive frames with an empty payload”). Node does not exhibit this.

Additional information

• grpcurl may appear to “work” because it tolerates the empty DATA frames and waits for trailers; Envoy is stricter and enforces an empty-frame guardrail.
• This likely sits in Bun’s Node-compat http2 server implementation used by @grpc/grpc-js.