recv_from can never return more bytes than the buffer size — the kernel truncates silently. == is the correct heuristic for detecting truncation. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Numa
DNS you own. Everywhere you go.
Block ads and trackers. Override DNS for development. Name your local services. Cache for speed. A single portable binary built from scratch in Rust — no Raspberry Pi, no cloud, no account.
Why
- Ad blocking that travels with you — 385K+ domains blocked out of the box. Works on any network: coffee shops, hotels, airports.
- Developer overrides — point any hostname to any IP with auto-revert. No more editing
/etc/hosts. - Local service proxy — access
https://frontend.numainstead oflocalhost:5173. Auto-generated TLS certs, WebSocket support for HMR. - Sub-millisecond caching — cached lookups in 0ms. Faster than any public resolver.
- Live dashboard — real-time query stats, blocking controls, override management, local services at
http://numa.numa(orlocalhost:5380). - Single binary, zero config — just run it.
Quick Start
From source
git clone https://github.com/razvandimescu/numa.git
cd numa
cargo build
sudo cargo run # binds to port 53, downloads blocklists on first run
Docker
docker build -t numa .
docker run -p 53:53/udp -p 5380:5380 numa
Try it
Open the dashboard: http://numa.numa (or http://localhost:5380)
dig @127.0.0.1 google.com # ✓ resolves normally
dig @127.0.0.1 ads.google.com # ✗ blocked → 0.0.0.0
Set Numa as your system DNS (all traffic goes through Numa):
sudo cargo run -- install # saves current DNS, sets system to 127.0.0.1
sudo cargo run -- uninstall # restores original DNS settings
# Or if installed to PATH:
sudo cp target/release/numa /usr/local/bin/
sudo numa install
sudo numa uninstall
Create an override:
curl -X POST http://localhost:5380/overrides \
-H 'Content-Type: application/json' \
-d '{"domain":"api.dev","target":"127.0.0.1","ttl":60,"duration_secs":300}'
dig @127.0.0.1 api.dev # → 127.0.0.1 (auto-reverts in 5 min)
Local Service Proxy
Name your local dev services with .numa domains instead of remembering port numbers:
# Register a service via API
curl -X POST http://localhost:5380/services \
-H 'Content-Type: application/json' \
-d '{"name":"frontend","target_port":5173}'
# Now access it by name
open http://frontend.numa # → proxied to localhost:5173
Or configure in numa.toml:
[[services]]
name = "frontend"
target_port = 5173
[[services]]
name = "api"
target_port = 8000
numa.numais pre-configured — the dashboard itself, accessible without remembering the port- HTTPS with green lock — auto-generated local CA + per-service TLS certs.
sudo numa installtrusts the CA in your system keychain. - WebSocket support — Vite/webpack HMR works through the proxy
- Health checks — dashboard shows green/red status for each service
- Services persist across restarts (
~/.config/numa/services.json) - Manage via dashboard UI or REST API
Resolution Pipeline
Query → Overrides → .numa TLD → Blocklist → Local Zones → Cache → Upstream → Respond
- Overrides — ephemeral, time-scoped redirects (highest priority)
.numaTLD — synthetic domains for local services → returns127.0.0.1- Blocklist — 385K+ ad/tracker domains → returns
0.0.0.0/:: - Local zones — records defined in
[[zones]]config - Cache — TTL-adjusted cached upstream responses (sub-ms)
- Forward — query upstream resolver, cache the result
- SERVFAIL — returned on upstream failure
Dashboard
Live at http://localhost:5380 when Numa is running:
- Total queries, cache hit rate, blocked count, uptime
- Resolution path breakdown (forward / cached / local / override / blocked)
- Scrolling query log with colored path tags
- Active overrides with create/edit/delete
- Local services with health status and add/remove
- Blocking controls: toggle on/off, pause 5 minutes, one-click allowlist
- Cached domains list
Configuration
numa.toml (all sections optional, sensible defaults if missing):
[server]
bind_addr = "0.0.0.0:53"
api_port = 5380
[upstream]
address = "8.8.8.8"
port = 53
timeout_ms = 3000
[cache]
max_entries = 10000
min_ttl = 60
max_ttl = 86400
[blocking]
enabled = true
lists = [
"https://cdn.jsdelivr.net/gh/hagezi/dns-blocklists@latest/hosts/pro.txt",
]
refresh_hours = 24
allowlist = []
[proxy]
enabled = true
port = 80
tld = "numa"
[[services]]
name = "frontend"
target_port = 5173
[[zones]]
domain = "mysite.local"
record_type = "A"
value = "127.0.0.1"
ttl = 60
HTTP API
REST API on port 5380 (22 endpoints):
| Endpoint | Method | Description |
|---|---|---|
/ |
GET | Live dashboard |
/overrides |
POST | Create override(s) |
/overrides |
GET | List active overrides |
/overrides |
DELETE | Clear all overrides |
/overrides/environment |
POST | Batch load overrides |
/overrides/{domain} |
GET | Get specific override |
/overrides/{domain} |
DELETE | Remove specific override |
/services |
GET | List local services (with health status) |
/services |
POST | Register a local service |
/services/{name} |
DELETE | Remove a local service |
/blocking/stats |
GET | Blocklist stats (domains loaded, sources, enabled) |
/blocking/toggle |
PUT | Enable/disable blocking |
/blocking/pause |
POST | Pause blocking for N minutes |
/blocking/allowlist |
GET | List allowlisted domains |
/blocking/allowlist |
POST | Add domain to allowlist |
/blocking/allowlist/{domain} |
DELETE | Remove from allowlist |
/blocking/check/{domain} |
GET | Check if domain is blocked |
/diagnose/{domain} |
GET | Trace resolution path |
/query-log |
GET | Recent queries (filterable) |
/stats |
GET | Server statistics |
/cache |
GET | List cached entries |
/cache |
DELETE | Flush cache |
/cache/{domain} |
DELETE | Flush specific domain |
/health |
GET | Health check |
How It Compares
| Pi-hole | NextDNS | Cloudflare | Numa | |
|---|---|---|---|---|
| Ad blocking | Yes | Yes | Limited | 385K+ domains |
| Portable | No (Raspberry Pi) | Cloud only | Cloud only | Single binary |
| Developer overrides | No | No | No | REST API + auto-expiry |
| Local service proxy | No | No | No | .numa domains + HTTPS + WebSocket |
| Data stays local | Yes | Cloud | Cloud | 100% local |
| Zero config | Complex setup | Yes | Yes | Works out of the box |
| Self-sovereign DNS | No | No | No | pkarr/DHT roadmap |
Use Cases
Block ads everywhere — Run Numa on your laptop. Your ad blocker works on any network.
Name your local services — frontend.numa instead of localhost:5173. CORS-friendly, HMR-compatible.
Mock external services — Point api.stripe.com to localhost:8080 for 30 minutes
Provision dev environments — Create overrides for db.dev, api.dev, cache.dev
Debug DNS — /diagnose/example.com traces the full resolution path
Built From Scratch
Zero external DNS libraries. RFC 1035 wire protocol parsed by hand. Dependencies: tokio, axum, serde, toml, reqwest (for blocklist downloads).
Roadmap
- DNS proxy core — forwarding, caching, local zones
- Developer overrides — REST API with auto-expiry
- Ad blocking — 385K+ domains, dashboard, allowlist
- System DNS auto-discovery — Tailscale, VPN split-DNS
- System DNS auto-configuration —
numa install/numa uninstall - Local service proxy —
.numadomains with HTTP/HTTPS reverse proxy, auto TLS, WebSocket - pkarr integration — self-sovereign DNS via Mainline DHT (15M nodes)
- Global
.numanames — self-publish, DHT-backed, first-come-first-served
License
MIT
