faucet-stream vs. Singer
Native connectors vs. the tap/target spec. What you gain, and what you give up.
Reflects the ecosystem as of 2026-07. Singer is an open spec with many runtimes (Meltano is the most common — see that comparison too).
The short version
Singer isn’t a tool — it’s an open specification: taps (extractors) and targets (loaders) exchange SCHEMA / RECORD / STATE messages as JSON over stdout. Its strength is a huge, language-agnostic ecosystem of taps and near-universal recognition.
faucet-stream takes the opposite approach: native connectors compiled into one binary, exchanging typed records in-process — no per-tap subprocess, no JSON serialization between stages, no Python. Third parties extend it through faucet’s own connector protocol (FCP) and SDK, not the Singer spec.
Be clear on one thing: faucet does not run Singer taps directly. This is native connectors vs. the tap model — you use faucet’s built-in connectors (or write an FCP one), not an existing Singer tap.
Where faucet-stream is different
- No inter-process serialization tax. Singer pipes JSON between a tap process and a target process; faucet moves typed records inside one binary. That, plus native Rust and no Python, is why a 1M-row move runs at 712k rows/s in 11.8 MiB (benchmarks).
- One artifact, not a pipeline of processes. A single static binary vs. a tap + target (+ a runner + Python envs).
- Governance & delivery guarantees in-path. Quality, contracts, masking, drift, lineage, SLAs, and effectively-once delivery are part of the engine — the Singer spec covers extract/load messaging, not these.
- A typed connector contract. faucet’s FCP protocol + SDK give connector authors a documented, versioned surface.
Where Singer is the better choice
- Ecosystem breadth. Hundreds of taps across many vendors and languages. If a specific long-tail source only exists as a Singer tap, that’s a real reason to use Singer (via Meltano or another runner).
- A known, open, language-agnostic spec. Write a tap in any language; huge prior art and community familiarity.
- You already run Singer taps and they work — inertia is a legitimate cost to weigh.
Side-by-side
| faucet-stream | Singer | |
|---|---|---|
| What it is | a runtime + native connectors | a message spec (taps/targets) |
| Process model | one binary, in-process records | tap process → JSON → target process |
| Language | Rust (connectors compiled in) | any (commonly Python) |
| Extensibility | FCP protocol + Rust SDK | the Singer spec |
| Runs existing Singer taps | ✗ (native connectors instead) | ✓ (that’s the point) |
| Governance / effectively-once | ✓ native | out of scope for the spec |
When to choose which
- Choose faucet-stream when performance, a single artifact, and in-flight governance matter, and your sources/sinks are covered by native connectors (or worth writing as an FCP connector).
- Stay with Singer (via Meltano or another runner) when you depend on a tap that only exists in the Singer ecosystem, or breadth trumps everything.
See for yourself
- faucet-stream vs. Meltano — the concrete runtime comparison.
- Connector catalog — what ships natively today.
- Authoring a connector — the FCP + SDK path.