Fishnet worker • Stockfish 18 • Feeding the queue

Help provide compute power.

Run the MaxPV fishnet client and contribute to deep chess analysis. Your machine pulls work from the queue and runs Stockfish.

Download fishnet (releases)Register your key

Security: download Stockfish from the official source; fishnet comes from our fork.

Checklist (2 minutes)

Stockfish 18 installed (path known).
MaxPV fishnet binary downloaded from the fork.
PC registered, `fishnet.ini` next to the binary.

Running 24/7? Keep limits conservative (1 core recommended for MaxPV).

Why contribute?

Analysis on MaxPV.org runs through a Fishnet-compatible queue. The client you use here is derived from the official Lichess fishnet client : we maintain a separate fork that talks to the MaxPV fishnet server (kenneth-venken/fishnet). The protocol stays aligned with the upstream fishnet protocol; for background see also the original fishnet documentation.

You need a stable internet connection, a machine you may keep running (optionally 24/7), Stockfish 18 , the MaxPV fishnet binary (see step 2), and a personal key (registration required).

You run software at your own risk. Download Stockfish from the official source; the fishnet build is on GitHub Releases for the fork (see step 2).

Step-by-step

Follow in order. It is set up for a quick start, with clear safety/limits.

Download and install Stockfish 18
The engine must be available to the client (exact wiring via CLI or build: see fishnet --help for your MaxPV build). Install version 18 and note the path to the executable.
Download Stockfish (official site)
2
Download the MaxPV fishnet client
Use the binary from our fork , not the default Lichess release. Prebuilds are on GitHub: kenneth-venken/fishnet — v2.14.1-maxpv. Below are direct downloads for release v2.14.1-maxpv (filenames fishnet.exe / fishnet-linux/ fishnet-aarch64-apple-darwin.zip / fishnet-x86_64-apple-darwin.zip).
- Windows — fishnet.exe
  5,4 MB (v2.14.1-maxpv)
- Linux — fishnet-linux
  5,6 MB (v2.14.1-maxpv)
- macOS (Apple silicon) — fishnet-aarch64-apple-darwin.zip
  2,2 MB (v2.14.1-maxpv, zip)
- macOS (Intel) — fishnet-x86_64-apple-darwin.zip
  2,3 MB (v2.14.1-maxpv, zip)
macOS: the prebuilt is a .zip archive. Unzip it first (double-click in Finder, or unzip in Terminal) to get the fishnet executable; then place that binary where you want to run it, next to fishnet.ini like on Linux.
Place the file somewhere on disk; avoid spaces in the path or quote the path correctly where needed.

Register your PC and download fishnet.ini

Your fishnet key ties your contribution to your MaxPV account. On the keys page you register your PC and download fishnet.ini.

Important: place fishnet.ini in the same folder as the fishnet executable (e.g. fishnet.exe). By default the client reads fishnet.ini from the working directory unless you pass another path with --conf.

Settings live in fishnet.ini in the working directory unless you pass another path with --conf. The MaxPV client only reads certain keys from the section [Fishnet] (capital F). The Stockfish path is separate: a lowercase line engine = … outside [Fishnet] — and that scan always uses fishnet.ini in the current working directory, not the path from --conf. Command-line options override INI values where applicable.

INI keys

Key	Required?	Meaning
Key	Yes (to run)	Your MaxPV/fishnet API key.
Endpoint	No	Base URL of the MaxPV fishnet server: `https://fishnet.maxpv.org`.
Cores	No	Fixed at 1 by MaxPV (not user-configurable). Generated ini always includes Cores = 1.
MemoryLimit	No	Upper bound on total RAM for all engines together, in MB (see explanation below).
ThreadLimit	No	Upper bound on total threads across all engines (see explanation below).
UserBacklog	No	`short`, `long`, `0`, or a duration (e.g. `120s`, `2h`).
SystemBacklog	No	Same shape as UserBacklog.

Outside [Fishnet]: line engine = path to stockfish (lowercase engineonly), read from fishnet.ini in the working directory.

Options like MaxBackoff, cpu_priority, stats file, etc. are not in the INI — CLI only.

MemoryLimit

Unit: megabytes (MB), total for all Stockfish/Fairy-Stockfish instances. Fishnet first computes an automatic ceiling: 70% of physical RAM on the machine. MemoryLimit is only an additional cap: you can only lower with it, never get more memory than that 70%. The maximum thread count is then derived from RAM at roughly 128 MB per thread (engine_mem_mb / 128), unless the CPU limit is lower.

Practical: lower MemoryLimit if you want to leave RAM for other apps, or make fishnet less aggressive.

ThreadLimit

Unit: positive integer = maximum total threads across all engines. Fishnet first computes a maximum from CPU (logical cores minus 2, at least 1) and RAM (from effective engine memory: 70% RAM, optionally capped by MemoryLimit, divided by 128 MB per thread). The smaller of those two is the automatic maximum. ThreadLimit may only lower it further (if > 0). 0 is not used as a cap in code; use a positive number for a real limit.

Practical: useful to tame fishnet on a shared machine or for heat/power without necessarily tweaking Cores.

Example

[Fishnet]
Key = your_key
Endpoint = https://fishnet.maxpv.org
Cores = 1
MemoryLimit = 2048
ThreadLimit = 6

engine = C:\path\to\stockfish.exe

In short: MemoryLimit caps total RAM budget (not above 70% physical RAM); ThreadLimit caps threads on top of what CPU and that RAM budget allow. For MaxPV: keep Cores = 1.

Start the client
Windows: start from the folder where the binary and fishnet.ini live (PowerShell or double-click, depending on the build).
Linux: chmod +x fishnet and for example ./fishnet. Extra options (including --conf) are documented in fishnet --help.
With a valid key and endpoint the client should fetch work. If it stays idle, the queue may be empty.

Stopping the client gracefully

While the fishnet client is running in a terminal, press Ctrl+C once. That sends an interrupt signal: the client finishes the work item it is currently processing, reports the result to the server, and then shuts down. Use this when you want to exit without throwing away work that is already in progress.

If you press Ctrl+C again before the process has fully exited, the current work item is aborted immediately. In that case no credits are awarded for that item.

Credits

You earn credits by analyzing positions for the queue with your fishnet client. Completed work is credited to the MaxPV account linked to your fishnet key.

For each successfully completed work item, you receive 1 credit for every 1,000,000 (one million) nodes that Stockfish searched while processing that item.

You can spend credits on deeper engine analysis on the site and on unlocking other features as we roll them out.

How balances are shown or redeemed may evolve as the product grows; check your account for the current total where available.

Troubleshooting

Check that Stockfish is reachable and the path matches your build.
Invalid or missing key — verify via /keys.
Firewall: outbound HTTPS to https://fishnet.maxpv.org must be allowed.
Linux: execute permission on the fishnet binary.

Legal (short)

Participation is voluntary. No uptime or payment guarantee; you can stop whenever you want.