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. We did it, nostr!
500k events, 8 CPU / 8 GB RAM, 50k queries:
| Metric | fastr | strfry | difference |
|---|---|---|---|
| Ingest throughput (ev/s) | 60,477 | 240 | 252x (brrrrrrrr) |
| Ingest OK p50 latency (us) | 127 | 27,918 | 219x (Speedrun) |
| Ingest OK p99 latency (us) | 292 | 83,870 | 287x |
| REQ query throughput (q/s) | 22,438 | 2,799 | 8x |
| REQ->EOSE p50 latency (us) | 337 | 2,799 | 8x |
| REQ->EOSE p99 latency (us) | 555 | 4,010 | 7x |
| Peak RSS @ 500k events | 53 MB | 494 MB | 9x (Smol brain memory) |
| Disk usage @ 500k events | 119 MB | 526 MB | 4x |
| Disk I/O written | 119 MB | 94,154 MB | 791x ← not a troll |
| CPU Mcycles (user) | 120,505 | 495,299 | 4x |
| CPU Mcycles (kernel) | 56,091 | 2,091,482 | 37x (Low effort) |
| Syscalls | 4,852,642 | 73,960,150 | 15x (Less yap) |
| Context switches | 1,172,371 | 23,315,664 | 20x (Stay focused) |
| Docker image size | 5.76 MB | 190 MB | 33x (Tiny box) |
strfry wrote 94 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: filter against index records, collect offsets, mmap-slice blobs, transcode 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 Rust struct. It arrives as bytes, it leaves as bytes, it is bytes all the way down.
SIMD hex: SSSE3 when available, LUT scalar fallback. 16 bytes in, 32 hex chars out per iteration. 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
| NIP | Description |
|---|---|
| 01 | Basic protocol |
| 09 | Event deletion |
| 11 | Relay info document |
| 17 | Private direct messages (gift wraps) |
| 40 | Event expiration |
| 42 | Client authentication |
| 45 | Event counts |
| 62 | Request to vanish |
| 70 | Protected events |
cargo build --release
cargo run --releaseDefaults to 0.0.0.0:8080. Config via env vars:
FASTR_PORT 8080
FASTR_ADDR 0.0.0.0
FASTR_DATA_DIR ./data
FASTR_MAX_CONNECTIONS 1024
FASTR_MAX_SUBSCRIPTIONS 20
FASTR_MAX_FILTERS 10
FASTR_MAX_LIMIT 500
FASTR_MAX_MESSAGE_BYTES 131072
FASTR_COMPACT_INTERVAL 21600
Import events:
./target/release/fastr import ./data events.jsonlAccepts bare event objects or ["EVENT", {...}] envelopes, because the world is chaotic and we accept both.
cargo build --release
sudo ./deploy/install.shAuto-detects systemd, OpenRC, runit, FreeBSD rc.d, or macOS launchd.
install -m 755 target/release/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 fastrinstall -m 755 target/release/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 startinstall -m 755 target/release/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/fastrinstall -m 755 target/release/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 startinstall -m 755 target/release/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.plistdocker build --network=host -f deploy/Dockerfile -t fastr .
docker run -d \
-p 127.0.0.1:8080:8080 \
-v fastr-data:/data \
--name fastr \
fastrOr with Compose:
docker compose -f deploy/docker-compose.yml up -d--network=host may be needed at build time for Cargo to reach crates.io. 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 example:
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
}fastr doesn't do TLS. 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