4 releases (breaking)

new 0.9.0 May 3, 2024
0.8.0 Mar 18, 2023
0.2.0 Mar 26, 2022
0.1.0 Sep 13, 2020

#146 in WebSocket

Download history 26/week @ 2024-02-18 4/week @ 2024-02-25 1/week @ 2024-03-10 12/week @ 2024-03-31 74/week @ 2024-04-28

75 downloads per month
Used in aquatic


3.5K SLoC

aquatic_ws: high-performance open WebTorrent tracker


High-performance WebTorrent tracker for Linux 5.8 or later.

Features at a glance:

  • Multithreaded design for handling large amounts of traffic
  • All data is stored in-memory (no database needed)
  • IPv4 and IPv6 support
  • Supports forbidding/allowing info hashes
  • Prometheus metrics
  • Automated CI testing of full file transfers

Known users:


WebTorrent tracker throughput comparison

More details are available here.



  • Install Rust with rustup (latest stable release is recommended)
  • Install build dependencies with your package manager (e.g., apt-get install cmake build-essential)
  • Clone this git repository and build the application:
git clone https://github.com/greatest-ape/aquatic.git && cd aquatic

# Recommended: tell Rust to enable support for all SIMD extensions present on
# current CPU except for those relating to AVX-512. (If you run a processor
# that doesn't clock down when using AVX-512, you can enable those instructions
# too.)
. ./scripts/env-native-cpu-without-avx-512

cargo build --release -p aquatic_ws


Generate the configuration file:

./target/release/aquatic_ws -p > "aquatic-ws-config.toml"

Make necessary adjustments to the file. You will likely want to adjust address (listening address) under the network section.

To run over TLS, configure certificate and private key files.

Running behind a reverse proxy is supported, as long as IPv4 requests are proxied to IPv4 requests, and IPv6 requests to IPv6 requests.


Make sure locked memory limits are sufficient:

  • If you're using a systemd service file, add LimitMEMLOCK=65536000 to it
  • Otherwise, add the following lines to /etc/security/limits.conf, and then log out and back in:
*    hard    memlock    65536
*    soft    memlock    65536

Once done, start the application:

./target/release/aquatic_ws -c "aquatic-ws-config.toml"

If your server is pointed to by domain example.com and you configured the tracker to run on port 3000, people can now use it by adding the URL wss://example.com:3000 to their torrent files or magnet links.

Load testing

A load test application is available. It supports generation and loading of configuration files in a similar manner to the tracker application.

After starting the tracker, run the load tester:

. ./scripts/env-native-cpu-without-avx-512 # Optional

cargo run --release -p aquatic_ws_load_test -- --help


Aims for compatibility with WebTorrent clients. Notes:

  • Doesn't track the number of torrent downloads (0 is always sent).
  • Doesn't allow full scrapes, i.e. of all registered info hashes

aquatic_ws has not been tested as much as aquatic_udp, but likely works fine in production.

Architectural overview

Architectural overview of aquatic

Copyright (c) Joakim Frostegård

Distributed under the terms of the Apache License, Version 2.0. Please refer to the LICENSE file in the repository root directory for details.


~761K SLoC