Primp 0.1.0

Primp.NET

.NET bridge for the primp HTTP client with browser impersonation.

Wraps the original Rust library via native interop for accurate TLS/HTTP2 fingerprinting — no reimplementation, just a thin P/Invoke bridge.

Features

• Browser Impersonation — Chrome, Safari, Edge, Firefox, Opera with real TLS/HTTP2 fingerprints
• OS Impersonation — Windows, macOS, Linux, Android, iOS
• Full HTTP — GET, POST, PUT, PATCH, DELETE, HEAD, OPTIONS
• Cookie Store — Automatic cookie persistence across requests
• Proxy Support — HTTP/HTTPS/SOCKS5 proxies
• Redirect Handling — Configurable follow-redirects with max limit
• Cross-Platform — Windows, Linux, macOS (x64 + ARM64)
• Multi-Target — .NET 8 and .NET 10

Installation

dotnet add package Primp

For dependency injection support:

dotnet add package Primp.Extensions

Quick Start

using Primp;

// Create a client impersonating Chrome 136
using var client = PrimpClient.Builder()
    .WithImpersonate(Impersonate.Chrome146)
    .WithOS(ImpersonateOS.Windows)
    .WithTimeout(TimeSpan.FromSeconds(30))
    .WithCookieStore(true)
    .FollowRedirects(true)
    .Build();

// GET request
using var response = await client.GetAsync("http://127.0.0.1:18080/get");
Console.WriteLine($"Status: {response.StatusCode}");
Console.WriteLine(response.ReadAsString());

// POST request with JSON
using var postResponse = await client.PostAsync(
    "http://127.0.0.1:18080/post",
    """{"key": "value"}""",
    "application/json");

Dependency Injection

using Primp.Extensions;

builder.Services.AddPrimpClient(options =>
{
    options.Impersonate = Impersonate.Chrome146;
    options.ImpersonateOS = ImpersonateOS.Windows;
    options.Timeout = TimeSpan.FromSeconds(30);
    options.CookieStore = true;
    options.FollowRedirects = true;
});

Then inject PrimpClient wherever you need it:

public class MyService(PrimpClient client)
{
    public async Task<string> FetchAsync(string url)
    {
        using var response = await client.GetAsync(url);
        return response.ReadAsString();
    }
}

API Reference

PrimpClientBuilder

Supported Browsers

PrimpResponse

Architecture

┌─────────────────────────────────────────────┐
│             Your .NET Application            │
├─────────────────────────────────────────────┤
│  Primp.dll  (managed, multi-target net8/10) │
│   PrimpClient · PrimpClientBuilder          │
│   LibraryImport / SafeHandle / Task.Run     │
├─────────────────────────────────────────────┤
│  primp_ffi.dll / .so / .dylib  (native)     │
│   ~15 extern "C" functions                  │
├─────────────────────────────────────────────┤
│  primp (original Rust crate by deedy5)      │
│   reqwest · rustls · h2 · hyper · tokio     │
└─────────────────────────────────────────────┘

Building from Source

Prerequisites

• .NET 8 SDK or later
• Rust toolchain (for native library)

Build native library

cd native/primp-ffi
cargo build --release

Build .NET solution

dotnet build primp.net.sln

Run tests

# Unit tests (no native library required)
dotnet test tests/Primp.Tests.Unit

# Integration tests (requires native library)
dotnet test tests/Primp.Tests.Integration

# CLI integration tests
dotnet test tests/Primp.Tests.Cli.Integration

Run benchmarks

dotnet run --project benchmarks/Primp.Benchmarks -c Release

Note: Benchmarks use PRIMP_BENCH_BASE_URL and default to http://127.0.0.1:18080.

Compare performance vs original primp

./scripts/compare-performance.ps1 -Iterations 20 -Warmup 3 -UseDockerForRust

./scripts/compare-performance.sh 20 3

Artifacts are written to:

• benchmarks/results/primp-dotnet.json
• benchmarks/results/primp-original-rust.json
• benchmarks/results/comparison-summary.json
• benchmarks/results/comparison-aggregate.json

Benchmark comparison (2026-03-31, 3 local runs)

Environment:

• primp.net measured in mcr.microsoft.com/dotnet/sdk:10.0-preview
• original primp measured in rust:1-bookworm
• workload: GET /get and POST /post against a local endpoint (mendhak/http-https-echo)
• warmup: 3, iterations: 20, repeated runs: 3

Interpretation:

• Across 3 local runs, primp.net stays consistently faster on both GET and POST in this setup.

.NET CLI Example

Small CLI app with common operations lives in examples/dotnet-cli.

dotnet run --project examples/dotnet-cli -- help
dotnet run --project examples/dotnet-cli -- version
dotnet run --project examples/dotnet-cli -- get http://127.0.0.1:18080/get
dotnet run --project examples/dotnet-cli -- post http://127.0.0.1:18080/post '{"hello":"world"}'
dotnet run --project examples/dotnet-cli -- headers http://127.0.0.1:18080/get
dotnet run --project examples/dotnet-cli -- tls

Platforms

License

MIT

Credits

• primp by deedy5 — the original Rust HTTP client with browser impersonation