High-Performance L4/L7 Network Proxy

MERIDIAN

Memory safety by construction, not convention.

A Rust-based reverse proxy informed by Envoy, HAProxy, and Nginx. Sub-nanosecond operations, zero-copy buffers, async filter chains. Where the compiler guarantees what code review cannot.

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0.38ns

Circuit Check

2.5 GB/s

Parse Throughput

0.73ns

LB Pick

Tests

100%

RFC Claims Pass

Explore

Why Another Proxy?

The Compiler Guarantees What Code Review Cannot

Every major proxy has had memory safety CVEs. Envoy, HAProxy, Nginx. Meridian is a ground-up reimplementation in Rust where entire vulnerability classes are eliminated at compile time.

Vulnerability Classes Eliminated

Eliminated
Buffer Overflows
Rust's ownership prevents buffer access beyond bounds
Eliminated
Use-After-Free
Borrow checker ensures references outlive their data
Eliminated
Double-Free
Single ownership model prevents duplicate deallocation
Eliminated
Data Races
Send + Sync traits prevent concurrent mutable access

Memory Safety by Construction
Not mitigated. Not caught by sanitizers. Eliminated at compile time.
0 unsafe
in app code
Sub-Nanosecond Operations
Config reads, circuit checks, and load balancer picks under 1ns.
0.38ns
CB check
Async Filter Chain
Filters are async fn, not callbacks. No manual state machines.
19ns
5-filter chain
Zero-Copy HTTP Parsing
2+ GB/s throughput using httparse with zero allocation in hot path.
2.5 GB/s
parse throughput

“Can you build a proxy that matches the performance of C++ proxies while providing memory safety guarantees that C++ structurally cannot?”

The benchmarks say yes.

FEATURE OVERVIEW

Production-ready features for platform engineers, SREs, and cloud-native infrastructure teams

ProtocolSecurityCoreRoutingResiliencePerformanceObservability

HTTP/1.1 proxy with keep-aliveProtocol
HTTP/2 downstream (h2 crate)Protocol
TLS termination (rustls)Security
Async filter chainCore
Round-robin load balancingRouting
Circuit breaker (RAII guards)Resilience
Connection poolingPerformance
Active health checking (TCP/HTTP)Resilience
Chunked transfer encodingProtocol
Admin API (/stats, /clusters)Observability
Path normalization & securitySecurity
Prometheus metrics endpointObservability
Fuzz-hardened parsersSecurity
Per-IP rate limitingSecurity
Slowloris defenseSecurity
Least-request (P2C) LBRouting
Maglev consistent hashingRouting
Request smuggling preventionSecurity

Features Done

Tests Passing

Fuzz Targets

RFCs

REQUEST TIMELINE

220 nanoseconds from arrival to upstream connection

T+0ns

Request Arrives

TCP accept loop receives connection

T+7.07ns

Buffer Acquired

Slab allocator provides hot buffer from pool

Vec::pop

T+193ns

Headers Parsed

httparse decodes HTTP/1.1 request at 2.5 GB/s

486B typical

T+212ns

Filter Chain

5-filter async pipeline processes request

~1ns/vtable

T+215ns

Route Matched

Config lookup via arc-swap shared reference

O(1) best

T+216ns

Endpoint Selected

Round-robin pick from cluster endpoints

counter + mod

T+216.4ns

Circuit Check

Single atomic load confirms circuit closed

0.38ns

T+220ns

Upstream Connect

Tokio timeout-wrapped connection to backend

RAII guard

~220ns

Request forwarded to upstream

Total overhead: < 250ns per request

DESIGN DECISIONS

These are settled. The result of extensive benchmarking and architectural analysis.

#1
Tokio Multi-Threaded Runtime
Not io_uring, not a custom event loop. Battle-tested async runtime.
Work-stealing scheduler, mature ecosystem, proven at scale.
#2
arc-swap for Config
Lock-free reads, O(1) swap for hot reload.
0.68ns config reads. No mutex contention on the hot path.
#3
httparse for HTTP/1.1
Zero-copy, proven, fuzz-hardened.
2.5 GB/s parsing throughput. No allocation in hot path.
#4
rustls for TLS
Pure Rust, no C FFI, Cure53 audited.
Eliminates entire class of C library vulnerabilities.
#5
RAII Guards for Limits
Circuit breaker and connection limits with automatic cleanup.
Resource release guaranteed on drop. No manual cleanup needed.
#6
Vec-based Filter Metadata
Linear scan beats HashMap for <8 entries.
1.6ns lookup vs 11.9ns with HashMap. Benchmarked decision.

BENCHMARK VERDICT

26 hard-target claims tested • 26 pass • All targets achieved

Pass Rate by RFC

RFC-0004Buffers

5/50%

RFC-0005Filters

4/40%

RFC-0006Codecs

5/50%

RFC-0007Config

2/20%

RFC-0008Load Bal

4/40%

RFC-0009Observability

3/30%

RFC-0010Resilience

3/30%

26/26

Claims Pass

100%

Pass Rate

5/5

Fixes Applied

Optimizations Applied

VecDeque overhead
Fixed: BufChain push/split
SmallVec
Applied
HashMap in hot path
Fixed: Counters, histograms
Indexed array
Applied
Instant::now() VDSO
Fixed: Token bucket
Loop timestamp
Applied
SipHash in Maglev
Fixed: Table build
ahash
Applied
HeaderMap::remove
Fixed: H1→H2 translation
retain() + set
Applied

WORKSPACE STRUCTURE

Modular Rust workspace with 63 passing tests

meridian-core

meridian-core/

tests

›buffer.rs — BufChain, SlabAllocator, Watermark

›codec.rs — Http1Codec, body framing, smuggling prevention

›config.rs — ConfigSnapshot, ConfigStore, route_lookup

›filter.rs — HttpFilter, DynamicFilterChain, typed metadata

›load_balancing.rs — RoundRobin, LeastRequest, MaglevHash

›resilience.rs — CircuitBreaker, TokenBucket, RetryPolicy

›observability.rs — IndexedStats, Histogram

meridian-proxy

meridian-proxy/

tests

›main.rs — Tokio runtime, config loading

›cluster.rs — ClusterManager + ClusterState

›connection.rs — L7 HTTP handler flow

›conn_limit.rs — Per-IP ConnectionLimiter

›metrics.rs — ProxyMetrics wrapper

meridian-bench

meridian-bench/

tests

›buffer.rs — Slab, BufChain benchmarks

›codec.rs — Parse throughput, header pool

›filter.rs — Chain, metadata benchmarks

›lb.rs — RR, P2C, Maglev benchmarks

›resilience.rs — CB, token bucket benchmarks

Features Implemented

L7 HTTP/1.1 ProxyKeep-AliveAsync Filter ChainTOML ConfigRound-Robin LBCircuit BreakerConnect TimeoutSlowloris DefensePer-IP LimitsPath NormalizationIndexed MetricsStructured Logging

QUICK START

Get Meridian running in under a minute

proxy.toml

1[[listeners]]
2name = "http"
3address = "0.0.0.0:8080"
4filter_chain = []
5 
6[[clusters]]
7name = "backend"
8lb_policy = "round_robin"
9connect_timeout_ms = 5000
10endpoints = [
11  { address = "127.0.0.1:9001", weight = 1 },
12  { address = "127.0.0.1:9002", weight = 1 },
13]
14 
15[[routes]]
16prefix = "/"
17cluster = "backend"

Build & Run

$ cargo build --releaseBuild the proxy
$ ./target/release/meridian proxy.tomlRun with config

Testing & Benchmarks

$ make test97 tests (unit + integration)
$ make clippyzero warnings
$ make bench7 Criterion benchmark suites
$ make fuzz7 libfuzzer targets

MERIDIAN

Vulnerability Classes Eliminated

Buffer Overflows

Use-After-Free

Double-Free

Data Races

Memory Safety by Construction

Sub-Nanosecond Operations

Async Filter Chain

Zero-Copy HTTP Parsing

Interactive Proxy Visualization

Performance Timeline

REQUEST TIMELINE

Request Arrives

Buffer Acquired

Headers Parsed

Filter Chain

Route Matched

Endpoint Selected

Circuit Check

Upstream Connect

Design Decisions

Tokio Multi-Threaded Runtime

arc-swap for Config

httparse for HTTP/1.1

rustls for TLS

RAII Guards for Limits

Vec-based Filter Metadata

Benchmark Results

Pass Rate by RFC

Optimizations Applied

VecDeque overhead

HashMap in hot path

Instant::now() VDSO

SipHash in Maglev

HeaderMap::remove

Architecture Overview

WORKSPACE STRUCTURE

meridian-core

meridian-proxy

meridian-bench

Features Implemented

Quick Start Guide

Build & Run

Testing & Benchmarks