Nix-Bitcoin review: a hardened NixOS node, now unmaintained

The top of the README now reads: "Archived and unmaintained as of August 13, 2026. v0.0.139 is the final release; there will be no further updates or security fixes." The v0.0.139 release notes open with the same message. The project's security fund is closed and no longer accepts reports or donations.

For node software this matters more than it would for a desktop app. A node runs Bitcoin Core, Lightning, an Electrum server, and a web stack, and every one of them gets security releases. Nix-Bitcoin pinned specific versions of each, so once it stops updating, your node stops getting those fixes unless you take over the packaging yourself. Under my rating methodology, a product no one maintains comes off every best list, and this page stays up as the record.

Nix-Bitcoin is a collection of Nix packages and NixOS modules for installing full-featured Bitcoin nodes with an emphasis on security. Instead of an app store and a web dashboard, you described your node in a NixOS configuration file, and the system built exactly that. It is free and released under the MIT license. Its three core developers, jonasnick, erikarvstedt, and nixbitcoindev on GitHub, held the keys to its security fund.

Even before it ended, the README said that while Nix-Bitcoin was used in production, it was still considered experimental.

This is the part Nix-Bitcoin got right, and why people chose it. Its secure-node preset routes every application's outbound traffic through Tor and accepts inbound connections through onion services. Each service runs as its own user with least privilege, restricted further by systemd sandboxing, RPC whitelisting, and an optional network-namespace isolation module, and there is a non-root operator account for daily commands. A hardened kernel is optional.

On the supply-chain side, the README says Nix pins every dependency exactly, packages can be built from source to reduce reliance on binary caches, merge commits are signed, and every commit is approved by more than one developer. The docs add one honest warning: if the computer you deploy from is insecure, Nix-Bitcoin cannot protect itself.

Nobody should start a new node on it. If you already run Nix-Bitcoin, nothing breaks overnight: v0.0.139 moved to NixOS 26.05 and shipped the last round of updates. The risk grows with every upstream security release you miss, so treat the time you have as a migration window.

For a new node, StartOS on a Start9 server is my top software pick, and it is what I run at home. Umbrel is the easiest, and RaspiBlitz suits a Raspberry Pi with a focus on Lightning. All three are on my node rankings, and my guide to running a Bitcoin node covers the hardware.

In October 2026, community members announced bitcoinix, an independent fork meant to keep the packages and modules updated. The announcement says the original maintainers are not involved, and Jonas Nick replied that he was looking forward to following its progress. The fork's latest release is v0.1.4, from November 2, 2026, and its own README calls the project and its documentation a work in progress.

I am not recommending it yet. A fork inherits the code, but not the review history or the people who earned trust over years of releases. If you run Nix-Bitcoin and like the NixOS approach, read the fork's changes before you point a node holding Lightning funds at it.

Nix-Bitcoin's installation guide manages the node from your own computer with the krops deployment tool, and the project also offers an importable configuration and a flake example for adding it to an existing NixOS system. Follow those docs for the commands. In outline:

The software is free. Its hardware page asks for 2 GB of RAM and 1 TB of disk for an unpruned Bitcoin Core, notes that electrs and Fulcrum do not support pruning, and lists the Raspberry Pi 4 among tested low-end hardware. Blockchain.com puts the blocks alone at about 781 GB as of November 7, 2026, before any database indexes, so 1 TB is now tight and a 2 TB SSD leaves room for Lightning and an Electrum index. The same page warns that some hardware, including Intel NUCs, may not work with the hardened kernel preset.

The project kept a public wall of fame of reported flaws. The final release fixed two, both found by the researcher haoxucu: netns-exec was executable by every normal user instead of only the operator, and LND's admin macaroon, which can move funds, was passed in a command line that other users on the machine could read. The release notes say both affected only hosts with a second, unprivileged user account and specific settings. An earlier report found that the release-fetching script skipped a hash check when the signature file held an inline message.

v0.0.137 in May 2026 patched the dirty.frag kernel vulnerability, CVE-2026-43500. That is the pattern you lose now: when the next flaw like it lands, no Nix-Bitcoin release will carry the fix. I track node and wallet incidents on my security incident log.

Nix-Bitcoin was a careful, security-first piece of node software, with Tor by default, least-privilege services, and a public record of the flaws it fixed. Its maintainers ended it cleanly with a final release and a plain notice. For a new node, choose StartOS, Umbrel, or RaspiBlitz. If you run Nix-Bitcoin today, move your node and Lightning channels to maintained software before your pinned versions fall behind on security fixes.