brpc — dami.projects

Architecture

brpc is a lightweight RPC framework built on JSON-RPC 2.0 over multiplexed TCP streams. It targets trusted networks — internal microservices, edge devices, localhost IPC — where gRPC is overkill and raw TCP is too low-level.

Components

Channel — Single TCP connection with multiplexed bidirectional streams, TLS, and compression
Frame — 10-byte binary header (stream ID + type + flags + payload length) for zero-overhead framing
Stream — Bidirectional ring buffers with window-based flow control per stream
RPC — JSON-RPC 2.0 method dispatch, request/response serialization, per-call timeouts
json_hotpath — Arena-based JSON parser and streaming writer for hot-path performance
TLS — OpenSSL-based encryption (optional, compile-time selectable)
Compression — zlib with negotiated compression via SETTINGS handshake (optional)
Profiling — Microsecond-granularity timing for RPC calls
Stats — Byte, frame, and stream counters for observability

Performance

Benchmarked on Intel i7-8xxx, Linux 7.x, cc -O2, single thread:

Operation	Latency	Throughput
JSON parse (28B)	0.1 us	6.75M msg/s
JSON serialize (small)	0.1 us	7.79M msg/s
Frame encode (128B)	0.1 us	12.5M/s
Stream write (1KB)	<0.1 us	24.1M/s
Channel round-trip	2.4 us	413K/s

Peak RSS: 2MB for all components.

Wire Protocol

Every frame is 10 bytes of header plus payload:

Offset  Size  Field
0       4     Stream ID (LE uint32)
4       1     Frame Type (DATA/HEADERS/SETTINGS/RST_STREAM/PING)
5       1     Flags (END_STREAM/COMPRESSED/PRIORITY)
6       4     Payload Length (LE uint32)

No magic bytes. No variable-length headers. No HPACK. Clean binary framing that maps directly to a C struct.

Python Bindings

Sync (ctypes) and asyncio wrappers included. Zero compilation required on the Python side:

from brpc import Channel

channel = Channel("localhost", 8080)
result = channel.rpc("math.add", [1, 2])

Building

git clone https://github.com/dev-dami/brpc
cd brpc
make

Requires a C99 compiler. OpenSSL is optional (for TLS). zlib is optional (for compression). Python bindings require Python 3.8+.

Tests: make test runs 114 C tests and 43 Python tests (157 total).

Blog

Read about the motivation and architecture in I Was Bored, So I Built a Faster RPC Framework in C.