A Nostr relay that goes brrrrrrrrrrrrrrrrrrrrrrrrr.

⚠️ Alpha software — expect bugs.

fastr is a Nostr relay that makes you reconsider every life choice that led you to running anything else. Your relay is slow. Your memory usage is embarrassing. Your disk is screaming. You already knew this in your heart. We just made it impossible to ignore.

500k events, 8 CPU / 8 GB RAM, 50k queries (2026-06-10):

Queries are O(limit), not O(event count): the index scan stops the moment nothing older can still make the top-N, and exact-id lookups don't scan at all. Reproduce with docker build -f Dockerfile.bench -t fastr-bench . && docker run --rm --privileged fastr-bench.

strfry wrote 83 GB of journal brainrot just to ingest 500k immutable events.
fastr wrote 119 MB.

data/
  data.n       BASED event blobs, append-only
  index.o      92-byte records: offset, created_at, expiry, kind, id, pubkey
  tags.s       49-byte records: tag name, value hash, event offset
  dtags.t      74-byte records: d-tag hash + kind + pubkey (addressable events)
  vanished.r   32-byte pubkey records (NIP-62)

Query path: scan index records newest-first with cheapest-first filter gates, reading fields straight from the mmap — no per-record decode. An in-memory prefix-max of created_at stops the scan as soon as nothing older can still crack the top-N (O(limit) for chronological ingest, not O(n)), and full-length id lookups skip the scan entirely via an id→slot map. Matching blobs are mmap-sliced and transcoded to JSON.

Write path: append blob, append index record.

Binary Append Store for Event Data. A compact format for Nostr events, designed for this workload specifically:

[id:        32 bytes]
[pubkey:    32 bytes]
[sig:       64 bytes]
[created_at: 8 bytes, LE i64]
[kind:       2 bytes, LE u16]
[tag_data_len: LEB128 varint]
  [tag_count: LEB128 varint]
  per tag:
  [nfields:   u8]
  per field:  [len_flag][data]
[content:    len_flag + data]

len_flag packs length and a hex flag into one byte. When is_hex is set, a 64-char hex string is stored as 32 binary bytes.

The first 138 bytes (id + pubkey + sig) are contiguous.

Transcoding to JSON wire format is one pass, zero heap allocations. The event never becomes a struct. It arrives as bytes, it leaves as bytes, it is bytes all the way down.

Hex: LUT scalar (SSSE3 SIMD pending). Matters because half of Nostr is hex strings of other Nostr things.

WebSocket batching: All events for a REQ get encoded into one batch with EOSE appended, handed to the write task as one message. N events = one TCP write.

Fanout: try_send to subscribers. Slow clients drop events, the writer doesn't wait.

Compaction: Every 6 hours, when tombstones exceed 1,000, a background task rebuilds the files.

fastr is written in Odin. One package per directory: pack (BASED format), nostr (validation, filters), store (storage engine), ws (WebSocket + handlers), negentropy (NIP-77), secp256k1 (bindings), cmd (the binary).

just vendor   # one-time: clone + build static libsecp256k1
just build    # -> ./fastr
just test     # run all package test suites

./fastr                           # serve on 0.0.0.0:8080
./fastr import ./data events.jsonl # bulk import

Accepts bare event objects or ["EVENT", {...}] envelopes, because the world is chaotic and we accept both.

just vendor && just build
sudo ./deploy/install.sh

Auto-detects systemd, OpenRC, dinit, runit, FreeBSD rc.d, or macOS launchd.

install -m 755 fastr /usr/local/bin/fastr
useradd -r -s /usr/sbin/nologin fastr
install -d -o fastr -g fastr /var/lib/fastr/data
cp deploy/fastr.service /etc/systemd/system/
systemctl daemon-reload
systemctl enable --now fastr

install -m 755 fastr /usr/local/bin/fastr
adduser -S -D -H -s /sbin/nologin fastr
install -d -o fastr -g fastr /var/lib/fastr/data
install -m 755 deploy/fastr.openrc /etc/init.d/fastr
rc-update add fastr default
rc-service fastr start

install -m 755 fastr /usr/local/bin/fastr
useradd -r -s /usr/sbin/nologin fastr
install -d -o fastr -g fastr /var/lib/fastr/data
install -m 644 deploy/fastr.dinit /etc/dinit.d/fastr
install -m 644 deploy/fastr.env /etc/dinit.d/fastr.env
dinitctl enable fastr

install -m 755 fastr /usr/local/bin/fastr
useradd -r -s /usr/sbin/nologin fastr
install -d -o fastr -g fastr /var/lib/fastr/data
mkdir -p /etc/sv/fastr
install -m 755 deploy/fastr.runit /etc/sv/fastr/run
ln -s /etc/sv/fastr /var/service/fastr

install -m 755 fastr /usr/local/bin/fastr
pw useradd fastr -s /usr/sbin/nologin -d /nonexistent -c "fastr nostr relay"
install -d -o fastr -g fastr /var/db/fastr/data
install -m 555 deploy/fastr.rc /usr/local/etc/rc.d/fastr
sysrc fastr_enable="YES"
service fastr start

install -m 755 fastr /usr/local/bin/fastr
sudo install -m 644 deploy/fastr.plist /Library/LaunchDaemons/com.arx-ccn.fastr.plist
sudo launchctl load -w /Library/LaunchDaemons/com.arx-ccn.fastr.plist

docker build --network=host -f deploy/Dockerfile -t fastr .
docker run -d \
  -p 127.0.0.1:8080:8080 \
  -v fastr-data:/data \
  --name fastr \
  fastr

Or with Compose:

docker compose -f deploy/docker-compose.yml up -d

--network=host may be needed at build time to fetch the Odin toolchain and libsecp256k1. The container itself runs without it, as a non-root user.

fastr does not handle TLS. Put a reverse proxy in front of it.

nginx:

server {
    listen 443 ssl;
    server_name relay.example.com;

    ssl_certificate     /etc/ssl/certs/relay.example.com.pem;
    ssl_certificate_key /etc/ssl/private/relay.example.com.key;

    location / {
        proxy_pass http://127.0.0.1:8080;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        proxy_set_header Host $host;
        proxy_set_header X-Real-IP $remote_addr;
    }
}

Caddy (handles cert renewal automatically):

relay.example.com {
    reverse_proxy 127.0.0.1:8080
}

TLS termination belongs at the edge, not in the relay. One proxy, one job.

strfry is respectable battle-tested software with years of production scars. If you want safe and proven, run strfry. If you want speed, run fastr.

This is young software, but the numbers are real. The "three years on the biggest relays" achievement is still loading. Beat us by 25% with the same features and we'll rename the project to slowstr. We're not even joking.

AGPLv3