Wisp is a lightweight Nostr relay written in Zig, built for people who want to run their own relay for a personal feed instead of relying on a large public server. It suits self-hosters, hobbyists and developers who want a small, fast program they can keep running on modest hardware. The current release is v0.9.1, and the most recent code update is dated October 17, 2026. The project is MIT licensed and free to use.
One caveat matters before you start. The project's documentation names Linux and Docker as the supported platforms, so a native Windows build is something to confirm on the GitHub Releases page rather than assume. This page explains what the program does, how to get it running on Windows if a build is available, and how it compares with the other Nostr tools in this catalog.
What Is a Nostr Relay?
Nostr is a simple, open protocol for social messaging. Users identify themselves with cryptographic keys, and every post is a signed event that can travel between apps and servers. The apps people use to read and write are called clients, and the servers that accept, store and return those events are called relays.
A relay is less glamorous than a client, but it does the essential work. It accepts events published by users, keeps them, and sends them back when a client asks for a particular author, topic or time range. Most users publish to several relays at once, so a post survives even if one server goes offline.
Relay operators decide a lot about how their server behaves. They choose which events to store, whether to require authentication, and how much history to keep. Wisp is one implementation of this server role, and understanding the relay's job makes its features easier to evaluate.
Who Wisp Is For
Wisp fits best with people who want to run their own relay and are comfortable working in a terminal. A typical user might keep a relay on a spare PC or home server so that their feed history lives on hardware they control. Because the program is small and efficient, it does not need a dedicated machine.
Developers form another group. If you are building a Nostr client, a local relay lets you test publishing, subscriptions and reconnection behavior without depending on a public server that may be slow or rate-limited. You can also export events to JSONL, adjust your test data and import it again.
Wisp is less suited to people who want a hosted service with no maintenance. Running any relay means watching uptime, keeping the software updated and making backups. If you prefer to simply open an app and post, a Nostr client from this catalog is probably the better starting point, and you can add a relay later.
Access Control and Private Messages
Relays can ask clients to prove they control a key before serving certain content. This is called authentication and is described in NIP-42. Once authentication is required, a relay can decide who may read specific events, which matters for content that is not meant to be public.
One example is kind 1059, the event type used for gift-wrapped messages in encrypted private communication. The message body is encrypted, but the surrounding metadata can still reveal who is communicating with whom. The project's notes suggest that reads for kind 1059 events should enable AUTH, so that only a client authenticated as the intended recipient can fetch them.
This is a good example of why relay configuration matters. Encryption protects the content, while access control limits who can ask for it. If you run a relay that holds private messages, review how authentication is set up before inviting anyone else to connect.
Key features
Fast throughput
Small single binary
One-command setup
Spider Mode
Embedded LMDB storage
Broad NIP support
Import and export in JSONL
Prometheus metrics
Supported coins
Wisp is a Nostr relay, so its network is Nostr itself. The project's documentation mentions only Nostr, and the program is not a cryptocurrency wallet, miner or exchange tool. If you are looking for software that handles coins or mining algorithms, a relay like Wisp is not designed for that purpose.
How to install Wisp on Windows
- 1
Find the Windows build
Open the project's GitHub Releases page at github.com/privkeyio/wisp and check the latest release, v0.9.1 at the time of writing, for a Windows binary. Download only from the official website or the GitHub Releases page, never from mirrors or unofficial download sites.
- 2
Verify the file
Compare the SHA-256 checksum of the downloaded file with the value published on the release page. If the project provides a signature instead, verify that as well. Do not run a file whose hash does not match.
- 3
Extract and place the program
Unzip the archive if needed and move the executable to a folder you control, such as C:\Tools\wisp. Avoid running it directly from the Downloads folder, where files are harder to track.
- 4
Start the relay
Open PowerShell in that folder and launch Wisp using the commands in the release documentation. Keep the window open while testing, or set up a background service once you are satisfied with the configuration.
-
Use Docker if no Windows build is listed
If the Releases page has no Windows binary, use Docker, which the project lists as a supported platform. Docker Desktop on Windows can run the Linux-based setup, so you can follow the Docker instructions from the documentation without a native build.
System requirements
- Roughly 11 MB of RAM at idle for the single binary, according to the project
- Linux and Docker are the platforms the project documents
- A Windows build is expected but should be confirmed on the Releases page before you plan around it
How to use Wisp
Once Wisp is running, the basic workflow is simple. Here is a typical setup for a personal relay that collects your own feed.
- Start the relay and note the address it listens on.
- Add that relay URL to your Nostr client's relay list.
- Publish a short test note and confirm it appears in the client and in the relay's output.
- Turn on Spider Mode so the relay begins syncing events from the people you follow.
- Open GET /metrics in a browser or a monitoring tool to confirm the relay is responding and to watch activity over time.
- Export your events to JSONL on a regular schedule and store the files somewhere separate from the server.
- Test an import with a copy of a backup file before you need it in an emergency.
- Review the release notes before updating, since the project is at version 0.9.1 and behavior can change between releases.
Keeping a short checklist like this helps you spot problems early, such as a relay that has stopped syncing or a backup that has not run for weeks.
Pros & cons
- Small memory footprint, about 11 MB at idle according to the project
- Single binary with a one-command start
- No separate database server to install or maintain
- Free to use under the MIT license, with the source code publicly available
- Built-in import and export in JSONL
- Prometheus metrics for monitoring relay activity
- Support for a long list of NIPs
- Native Windows support is not clearly confirmed, so check the Releases page before planning around it
- Version 0.9.1 indicates pre-1.0 software, so interfaces and behavior may still change
- Narrow scope: it is a relay only, not a client, wallet or hosted service
- You manage uptime, backups and security yourself
Is Wisp safe?
A relay accepts connections from other computers, so treat it like a small server rather than an ordinary app. Download only from the official website, meaning the project's GitHub repository and its Releases page at github.com/privkeyio/wisp. Check the SHA-256 checksum or signature before running anything. Wisp is MIT licensed, so you can also review the source code yourself. Open only the network port you need, avoid running the program with administrator rights, and keep it updated. The project's most recent code update is recent rather than abandoned, but because it is pre-1.0, check the latest version on the official website before installing. A relay does not need a seed phrase or wallet keys, so never enter one on any website claiming to help you set it up.
- Official source only. Download from github.com/privkeyio/wisp. Ignore ads and lookalike domains.
- Check the SHA-256. Compare the installer hash with the value the developer publishes before running it.
- Never share your seed phrase. No developer, support agent or website — including CryptApps — will ever ask for it.
Alternatives
Most tools in this catalog are Nostr clients, the apps you use to read and write posts. Amethyst, Gossip and Vega help you browse and publish, while Wisp sits on the server side and stores events for your clients. NAK and Nostr Commander RS are command-line tools, which feel closer to Wisp's terminal-based workflow, but they still act as clients rather than relays. Nostr VPN is a different kind of project, a mesh VPN built on Nostr signaling. Compared with strfry, the relay the project uses as its benchmark point, Wisp emphasizes a single small binary and embedded LMDB storage. Choose based on whether you need a server you run yourself or an app for everyday use.
Specifications
- Price
- Free
- Type
- Open source
- License
- MIT
- Latest version
- v0.9.1
- Last update
- 17 Oct 2026
- Windows support
- Likely (builds for Windows; check releases)
- Source code
- github.com/privkeyio/wisp
Frequently asked questions
The project documentation names Linux and Docker as supported platforms, and Windows support is listed as likely rather than confirmed. Check the GitHub Releases page for a Windows binary in the latest version, v0.9.1. If none is there, you can run Wisp through Docker Desktop on Windows instead.
Wisp is open source under the MIT license, so its code can be reviewed publicly. Safety depends on how you install and expose it. Download from the GitHub Releases page, check the checksum, and open only the port you need. A relay does not require a seed phrase or wallet keys.
No. Wisp stores events in LMDB, an embedded storage engine that runs inside the program, so there is no separate database server to install. That keeps setup short and reduces the number of services you must keep running on your machine.
According to the project, Wisp uses about 11 MB of RAM at idle as a single binary. Actual usage rises with traffic, the number of stored events and your configuration, so measure it on your own hardware under a realistic load before choosing where to host it.
Yes. Wisp is released under the MIT license, which allows you to use, modify and redistribute the code under the license terms. The main costs of running it are the hardware, electricity and bandwidth you use to host the relay.
Yes. Wisp supports importing and exporting events in JSONL, a line-based format where each event occupies one line. Export a file in JSONL, then import it into Wisp. Test with a copy first so you can confirm the events arrived intact before relying on the backup.
Spider Mode syncs events from the people you follow and from external relays, so your relay collects posts you care about. Once it is configured, it runs automatically, which makes it useful for keeping a personal archive of a feed without copying events by hand.
Verdict
Wisp suits people who want a small, fast, self-hosted Nostr relay and are comfortable with a command-line setup. It is a good fit for a home server or spare machine that stores your own feed. If you need a native Windows build, confirm it on the GitHub Releases page first. If none exists, Docker is the documented route. Because the project is pre-1.0, treat it as young software, keep backups, and check the latest version on the official website before installing.