Metadata-Version: 2.4
Name: serviette
Version: 0.1.8
Summary: A no-code RAG server that keeps answers in sync with your documents. Works with 8 vector databases. Built on Pathway.
Author: serviette contributors
License: MIT License
        
        Copyright (c) 2026 Sergey Kulik
        
        Permission is hereby granted, free of charge, to any person obtaining a copy
        of this software and associated documentation files (the "Software"), to deal
        in the Software without restriction, including without limitation the rights
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Project-URL: Homepage, https://pathway.com
Project-URL: Documentation, https://github.com/pathwaycom/serviette
Keywords: rag,retrieval-augmented-generation,pathway,vector-database,retrieval,llm,embeddings,document-search,semantic-search,real-time,no-code,self-hosted
Classifier: Programming Language :: Python :: 3
Classifier: Programming Language :: Python :: 3.10
Classifier: Programming Language :: Python :: 3.11
Classifier: Programming Language :: Python :: 3.12
Classifier: Programming Language :: Python :: 3.13
Classifier: Programming Language :: Python :: 3.14
Classifier: License :: OSI Approved :: MIT License
Classifier: Operating System :: OS Independent
Requires-Python: >=3.10
Description-Content-Type: text/markdown
License-File: LICENSE
Requires-Dist: pathway[xpack-llm]>=0.32.1
Requires-Dist: fastapi>=0.110
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Dynamic: license-file

# serviette

<p align="center">
  <a href="https://pypi.org/project/serviette/"><img src="https://img.shields.io/pypi/v/serviette?logo=pypi&logoColor=white" alt="PyPI version"></a>
  <a href="https://pypi.org/project/serviette/"><img src="https://img.shields.io/pypi/pyversions/serviette?logo=python&logoColor=white" alt="Python versions"></a>
  <a href="https://github.com/pathwaycom/serviette/blob/main/LICENSE"><img src="https://img.shields.io/github/license/pathwaycom/serviette" alt="License: MIT"></a>
  <a href="https://github.com/pathwaycom/serviette/actions/workflows/ci.yml"><img src="https://github.com/pathwaycom/serviette/actions/workflows/ci.yml/badge.svg" alt="CI"></a>
</p>

**A no-code, always up-to-date RAG server for any vector database — built on
the [Pathway Live Data Framework](https://github.com/pathwaycom/pathway).**

Point serviette at a folder of documents, pick a vector database and an
embedder in one YAML file, and run two commands: you get a chat and a REST API
that answer from those documents and cite their sources. From then on, any
change to the documents — an edit, a new file, a deletion — is reflected in
the answers within seconds.

serviette runs on Pathway, which needs a **free license key** — one click at
<https://pathway.com/framework/get-license> (GitHub or LinkedIn sign-in). Every
command below expects it in `PATHWAY_LICENSE_KEY`.

Try it in four commands:

```bash
pip install serviette
export PATHWAY_LICENSE_KEY=...        # free: https://pathway.com/framework/get-license
export OPENAI_API_KEY=sk-...
serviette demo --embedder openai      # → chat at http://localhost:8989
```

**Use pip 23.1 or newer** (`python -m pip install -U pip` first): older pip lacks
the resolver improvements this dependency tree needs and can take hours.

This indexes a [small bundled corpus](https://github.com/pathwaycom/serviette/tree/main/serviette/demo/corpus) (a fictional
coffee-machine company) into `./serviette-demo/docs` and opens a chat over
it. Edit or drop files into that folder while it runs — the answers
follow within seconds.

<p align="center">
  <img src="https://raw.githubusercontent.com/pathwaycom/serviette/main/docs/assets/demo.gif" alt="serviette demo: the terminal output up to the Ready line, the chat answering a question, a one-line edit of a document in a second terminal, and the same question answered with the new value" width="100%">
</p>
<p align="center"><em>One command to a live RAG stack — then edit a document and watch the answer change.</em></p>

## Who is it for

**What you get.** A question-answering assistant over your organisation's
documents, with sources cited and answers that follow the documents: an edit,
a new file or a deletion is reflected within seconds, with no re-upload or
re-indexing step for anyone to run or forget.

**What it costs to run.** Two processes (an indexer and a server) and one YAML
file. Embeddings can be computed locally for free; the Pathway license is
free; the only metered component is the optional model API that writes the
answer text, billed per question rather than per document.

**Where your data goes.** Nowhere by default. With the default local
embedder, documents, their embeddings and the index stay on the machine or in
the database you choose; the only thing that leaves is the handful of passages
retrieved for a question, sent to the model API that writes the answer — and
only if you configure one. (Choosing an API embedder instead sends the
document text through that API as well.)

**How mature it is.** serviette is a thin layer over the
[Pathway Live Data Framework](https://github.com/pathwaycom/pathway) — the
open-source engine that does the watching, parsing, embedding and writing: in
development since 2022, 60 000+ GitHub stars, in production use at
organisations such as
[DB Schenker](https://pathway.com/success-stories/db-schenker),
[Intel](https://pathway.com/framework/blog/intel-summit),
[NATO](https://pathway.com/blog/jsec-pathway-ai-collaboration-steadfast-foxtrot-2024),
[La Poste](https://pathway.com/success-stories/la-poste),
[Transdev](https://pathway.com/success-stories/transdev) and
[CMA CGM](https://pathway.com/success-stories/cma-cgm).
serviette's own numbers are measured, not estimated: indexing
up to 50 GB of text (26 million pages, 17 million files) in constant memory,
retrieval accuracy on a public benchmark (FRAMES), eight vector databases
under integration tests against real instances — all reproducible from this
repository.

**Where it stands today.** It answers one question at a time, from the
current state of the documents. Conversation memory, user accounts and a
hosted offering are not built in yet — and each is a short step from what is
here. If your use case needs one of them, or something else, contact us for a
tailor-made solution:
[open an issue](https://github.com/pathwaycom/serviette/issues), write on
[Discord](https://discord.gg/pathway), or email
[contact@pathway.com](mailto:contact@pathway.com).

The rest of this README is for the person setting it up.

To run it over your own documents, generate a config and start the stack:

```bash
pip install "serviette[local]" --extra-index-url https://download.pytorch.org/whl/cpu
    # [local] = free local embeddings, the wizard's default. It brings PyTorch; the
    # --extra-index-url picks its CPU build (~0.8 GB) instead of the default one
    # with CUDA libraries (~5 GB) — drop the flag only if you will embed on an
    # NVIDIA GPU. Plain `pip install serviette` if you will embed with OpenAI instead.
export PATHWAY_LICENSE_KEY=...   # the free Pathway license (see above); the wizard picks it up from here
export OPENAI_API_KEY=sk-...     # powers generated answers; omit to run keyless (answers quote the retrieved snippets)

serviette wizard                           # interactive config wizard
serviette up --config config.yaml          # indexer + server together → http://localhost:8989
```

(Production deployments run `serviette indexer` and `serviette server`
separately — that is what `up` supervises.)

The server hosts both the web chat UI (on `/`) and the versioned REST API
(under `/api/v1`) on one port:

```bash
curl -X POST http://localhost:8989/api/v1/retrieve \
  -H 'Content-Type: application/json' \
  -d '{"query": "how does persistence work?", "k": 5}'
```

## Highlights

- **No code.** Configure everything in one YAML file (or generate it with
  `serviette wizard`).
- **Any vector DB — 8 backends.** DuckDB (embedded, zero setup — the default),
  pgvector, Qdrant, Milvus, ChromaDB, Weaviate, Pinecone and MongoDB Atlas
  Vector Search. Every backend is written through **Pathway's native
  connectors**, so file edits and deletions become real upserts/deletes in
  the store.
- **Zero-setup default.** DuckDB is the default backend: an embedded
  database in a single local file, no external service to install or run,
  with built-in vector search.
- **Live & incremental.** Built on Pathway: additions, edits and deletions
  are reflected in the vector DB in real time — whatever you change is
  answerable seconds later. Documents flow through the pipeline instead of
  accumulating in it, so a large corpus stays small in memory.
- **Multiple sources.** Local filesystem, Google Drive, S3/MinIO, SharePoint
  — plus anything the PyFilesystem library opens: FTP, SFTP, WebDAV, even ZIP
  archives. All watched live, mixed freely in one config.
- **Multimodal out of the box.** Text, Office documents, PDFs (with tables
  and layout), scanned images — and, with the corresponding API keys, audio
  recordings and even video. Every format is on by default and routed to the
  best parser that needs no API key; drop a file in the folder and it is
  answerable like any document. See [Multimodality](#multimodality).
- **Reuses Pathway's LLM xpack.** Parsers, splitters and embedders are used
  as-is — serviette implements none of its own. Five embedder families (OpenAI,
  LiteLLM, SentenceTransformers, Gemini, Bedrock) work identically on the
  indexer and the server side — including a fully local, credential-free
  stack with local embeddings + DuckDB.
- **Decoupled & scalable.** Indexer and API server are independent processes
  sharing only the vector DB. The server is stateless and scales
  horizontally; the indexer shards across worker processes with one config
  line. Every part scales on its own.
- **Web chat UI, same port.** `serviette server` serves a clean
  ChatGPT/Claude-style chat page on `/` next to the versioned API
  (`/api/v1/...`) — same origin, no CORS, nothing extra to run. For split
  deployments (UI on a different host) there is a standalone
  `serviette frontend` proxy tier.
- **Free Pathway license.** One click at
  <https://pathway.com/framework/get-license>.

## Architecture

<p align="center">
  <img src="https://raw.githubusercontent.com/pathwaycom/serviette/main/docs/assets/architecture.svg" alt="serviette architecture: sources feed the Pathway indexer, which writes through Pathway's native connectors into one of 8 vector databases; the stateless server embeds queries, searches the database and serves the chat UI and the /api/v1 REST API" width="100%">
</p>

**The two halves are fully decoupled.** The indexer (write path) and the
server (read path) are separate processes — different executables that never
talk to each other. Their only contract is the vector database itself:

- **Independent scaling.** The server is stateless and read-only — run any
  number of instances behind a load balancer; each also serves the chat UI at
  zero cost. The indexer scales separately: Pathway shards it across worker
  processes (`indexer.workers: 8` is how the benchmarks below run), so every
  part of the stack scales independently. Bulk re-indexing never slows down
  query serving, and query spikes never stall indexing.
- **Failure isolation.** If the indexer is down, serving continues over the
  last-synced data; if the server is down, indexing keeps the database fresh.
  Either side can be restarted or upgraded independently (the indexer resumes
  from its persistence without re-embedding).
- **The database stays yours.** Vectors live in *your* store in a plain,
  documented schema — other consumers (BI, other apps, a different retrieval
  stack) can read the same collection; serviette doesn't hold it hostage. And
  since the default store is an embedded DuckDB file, trying this out costs
  nothing to set up.
- **Optional third tier.** For split deployments (UI on a different host than
  the API) a standalone `serviette frontend` serves the same chat page and
  proxies to the API server-side.

The one deliberate exception: the embedded DuckDB backend trades this
distribution for zero setup — one local file, single-writer, ideal for
laptops and demos (see [docs](https://github.com/pathwaycom/serviette/blob/main/docs/README.md) for its concurrency note).

## Benchmarks

Two self-contained benchmarks, one per axis: what indexing costs in time
and memory, and how accurate the retrieval is.

### Indexing resources

Self-contained benchmark (docker-compose: Qdrant + indexer + server, fully
local embeddings, zero API cost) over a Wikipedia corpus of plain text —
every byte below is extracted text (a PDF collection with the same text
content would weigh several times more) —
see [benchmarks/realtime-data-indexing](https://github.com/pathwaycom/serviette/tree/main/benchmarks/realtime-data-indexing):

| corpus | ≈ pages | files | chunks | indexing time | peak memory (PSS) | in Qdrant |
|---|---|---|---|---|---|---|
| 100 MB | 52 000 | 12 969 | 66 136 | 39 s | 6.6 GB | 0.6 GB |
| 1 GB | 524 000 | 240 516 | 836 595 | 4.8 min | 6.9 GB | 2.2 GB |
| 3 GB | 1 573 000 | 841 890 | 2 703 850 | 15 min | 7.3 GB | 6.0 GB |
| 10 GB | 5 243 000 | 3 423 359 | 10 093 514 | 58 min | 7.7 GB | 20.8 GB |
| 30 GB | 15 729 000 | 9 202 620 | 29 817 294 | 2.9 h | 10.1 GB | 61.3 GB |
| 50 GB | 26 214 000 | 17 083 603 | 53 913 774 | 5.5 h | 13.1 GB | 107.9 GB |

Documents flow through the pipeline rather than accumulating in it, so
what stays in memory is short and worth spelling out.

**Grows with the corpus — one thing.** The file-watch index: to detect live
edits and deletions, the indexer keeps a record (path, mtime, size, owner)
per watched file. Measured cost: **~318 bytes per file** (paths of typical
length; ±20% with the hash-table's load factor), verified from 13 thousand
to 17 million files (right-hand plot: six corpus sizes against one fitted
line). It scales with the *number of files*, not bytes: the same corpus
packed into fewer, larger files costs proportionally less.

**Constant, regardless of corpus size.** The embedding stack (PyTorch
runtime + model, per worker), the engine baseline (~200 MB per process),
connector machinery (~0.4 GB), and working buffers that reach a plateau in
the first minutes of a run and stay there — identical on 3 GB and 10 GB.

**On disk, not in memory.** Parsed-text cache, persistence snapshots, and
the embeddings themselves (in the vector database). That is why the curves
plateau: a **500× larger corpus costs 2.5× the memory** — and the growth
that remains is the file-watch index above, i.e. the corpus in fewer files
would cost less. Indexing time scales linearly with bytes throughout.

<p align="center">
  <img src="https://raw.githubusercontent.com/pathwaycom/serviette/main/docs/assets/bench-memory.png" alt="Left: indexer PSS over time for corpora from 100 MB to 50 GB, from the run before the allocator tuning; every curve reaches its plateau in the first minutes and holds it for hours. Right: connector-worker extra memory across six corpus sizes follows ~318 bytes per watched file" width="100%">
</p>
<p align="center"><em>Curves from the run <strong>before</strong> the allocator tuning (peaks 6.6–16.4 GB); the table above has the final numbers from the tuned rerun (6.6–13.1 GB). The shape is the point: each curve reaches its plateau in the first minutes and holds it for the rest of the run — 5.5 hours for 50 GB.</em></p>

The peak itself is dominated by the embedding stack, not the engine — a
Pathway worker process is ~200 MB; the rest is the price of running
embeddings locally (8 × PyTorch runtime + model), i.e. of paying no
per-token API fees. Fewer workers or an API embedder shrink it accordingly.

<p align="center">
  <img src="https://raw.githubusercontent.com/pathwaycom/serviette/main/docs/assets/bench-memory-breakdown.png" alt="Breakdown of the 10 GB corpus peak as measured in the run before the allocator tuning (8.8 GB): three quarters is the local PyTorch embedding stack across 8 workers; file-watch metadata is about 1.1 GB; supervisors and shared code make up the rest" width="85%">
</p>
<p align="center"><em>Same earlier run (8.8 GB peak on the 10 GB corpus; 7.7 GB after tuning). The proportions are what matters here: the embedding stack dominates, the engine and the file-watch index are small.</em></p>

Memory is measured as PSS (proportional set size) summed over the container:
shared pages — e.g. the PyTorch libraries mapped by every worker — are
counted once, not once per process. Setup: 96-core CPU host, streaming mode,
8 worker processes, local `static-retrieval-mrl-en-v1` embeddings (no API
calls; Matryoshka-truncated to 256 dims), 512-token chunks, Qdrant, and
jemalloc's `background_thread` purging enabled in the indexer containers
(measured free; it keeps idle workers from retaining freed pages). Numbers
were measured on a nightly Pathway build whose engine matches the released
wheel (pathway ≥ 0.32.1 — what the benchmark's docker image and the
Development section install), so they are reproducible as-is.

### Retrieval accuracy (FRAMES)

End-to-end evaluation on [FRAMES](https://arxiv.org/abs/2409.12941)
(Google, 2024): 824 multi-hop questions whose answers must be assembled
from 2–15 English Wikipedia articles — see
[benchmarks/frames](https://github.com/pathwaycom/serviette/tree/main/benchmarks/frames), full technical report in
[REPORT.md](https://github.com/pathwaycom/serviette/blob/main/benchmarks/frames/REPORT.md):

| measurement | result |
|---|---|
| gold-article recall — the paper's metric, on the paper's corpus | **0.50** vs 0.15 published for the paper's BM25 baseline (0.21 for our reproduction of it) |
| paired gain from adding serviette to gpt-5, paper's protocol | **+5.2 pp** over the same model without retrieval (McNemar z = 4.1, 824 questions) |
| adaptive retrieval in the grounded (context-only) regime | **41.3% → 52.8%** (z = 7.5) — the largest single effect measured |
| absolute accuracy (permissive, gpt-5) | **73.7%** — above every number in the paper, including its 5-step agent (66.0%) and oracle (72.9%) |

The setup reproduces the paper wherever technically possible: the identical
Wikipedia dump (TFDS `wikipedia/20230601.en`, 5.22M articles → 12.07M
chunks) indexed in full by serviette with the free local `e5-small-v2`
embedder — so the recall row costs nothing in API fees — plus the paper's
own retrieval metric and its verbatim autorater prompt. Comparisons are
paired and internal (identical corpus, generator, judge; only the retrieval
layer varies — the opt-in strategies described under
[Retrieval quality](#retrieval-quality) below), because the absolute score
is dominated by the 2026
generator — its no-retrieval baseline alone reaches 68.5% — which is why
the headline is the paired delta, not 73.7%. The grounded rows measure
serviette as it ships for private corpora: answers strictly from retrieved
documents, a deliberately stricter regime than the paper's. Methodology,
statistics, limitations and raw per-question outputs:
[REPORT.md](https://github.com/pathwaycom/serviette/blob/main/benchmarks/frames/REPORT.md).

## Multimodality

Every file type is enabled by default. serviette routes each file to the best
parser that works **without an API key**, and turns on key-requiring
modalities automatically when their key is present:

| format | parsed by default with | notes |
|---|---|---|
| text / Markdown | as-is | |
| PDF | pypdf — **built in**; `serviette[docling]` upgrades to Docling (layout-aware, tables) | local, free |
| Office (DOCX, PPTX, XLSX, HTML, EML…) | Unstructured — **built in**; `serviette[docling]` widens coverage (EPUB, legacy formats) | local, free |
| scanned images (PNG, JPG, TIFF…) | PaddleOCR | local, free; install `serviette[ocr]` |
| audio (MP3, WAV…) | Whisper | when `OPENAI_API_KEY` is set |
| video (MP4, WebM, MOV…) | TwelveLabs Pegasus — a searchable text description of the video | when `TWELVELABS_API_KEY` is set |

A modality whose only parser needs an absent key is skipped with a clear
warning — never a crash. Everything stays live: drop a recording of
yesterday's meeting into the watched folder and ask about it minutes later;
expensive parses (video) are cached on disk, so restarts cost nothing.

The routing is configurable per file pattern (`parser:` section — pick a
vision model for images instead of OCR, set a custom video prompt); see
[docs](https://github.com/pathwaycom/serviette/blob/main/docs/README.md). Embeddings work the same for every modality: parsed
content is text, so any of the embedder families — including the local
credential-free default — covers a multimodal corpus.

## Retrieval quality

Retrieval and answering are pure-vector by default; five opt-in strategies
improve accuracy, each a few lines of config. They compose freely — decompose
widens *what* is retrieved, hybrid and reranking reorder *which* chunks win,
MMR *diversifies* them, and adaptive RAG *retries* with more context when the
answer is not found.

- **Hybrid (BM25 + vector).** Fuses vector similarity with an in-process BM25
  keyword index (reciprocal-rank fusion). The two signals fail differently —
  embeddings match paraphrases, BM25's IDF makes rare exact tokens (names,
  dates, IDs) dominate — so their fusion beats either alone on entity-heavy
  corpora. Enable with `hybrid: true` on the vector-db section.
- **Reranker.** A second stage rescoring a shortlist of candidates: a local,
  keyless cross-encoder (`reranker: {type: cross_encoder}`) or pointwise LLM
  scoring (`type: llm`). Best for precise, single-hop questions.
- **Adaptive RAG.** Answers from `k` chunks first, then grows the context and
  re-asks while the LLM reports the answer is not present (`rag.adaptive`).
  Your `llm.system_prompt` stays in force; the mode only appends the
  "reply with this marker when the context is insufficient" instruction it
  needs to decide when to fetch more.
- **Query decomposition.** One LLM call splits a multi-hop question into
  sub-queries, retrieves for each, and fuses — so chunks of different hops
  stop competing for the same top-k slots (`rag.decompose`).
- **MMR.** Diversifies the result set, trading relevance against redundancy
  (`rag.mmr`).
- **Document questions.** "How many documents do you have?", "What does
  `journal.pdf` say?", "What changed between `law_2023.txt` and
  `law_2024.txt`?" are questions about documents, not about a passage, and
  chunk retrieval cannot answer them. `rag.documents` (on by default) answers
  them from the document catalog and from whole files: a question naming a
  file goes straight to that file; any other question is searched as usual,
  and only if that finds nothing does one short LLM call decide between a
  wider search and the catalog or the named documents. Two files that share
  most of their text are compared as a line-level diff computed by the
  server, so the model reads only what changed — however the files were
  chunked. Every step has a fixed context budget and the request as a whole
  a ceiling (`max_request_chars`); when a file cannot be identified the
  answer says which names were close.
  Not available on Pinecone, which cannot enumerate documents.

The reranker and the multi-step strategies (adaptive, decompose) are
backend-independent — they work on every vector DB. Hybrid and MMR read from
the store, so support depends on the backend:

| Backend  | Vector | Reranker · Adaptive · Decompose | MMR | Hybrid (BM25) |
|----------|:------:|:-------------------------------:|:---:|:-------------:|
| DuckDB   | ✅ | ✅ | ✅ | ✅ in-process |
| Qdrant   | ✅ | ✅ | ✅ | ✅ in-process |
| pgvector | ✅ | ✅ | ✅ | ✅ in-process |
| Milvus   | ✅ | ✅ | ✅ | ✅ in-process |
| Weaviate | ✅ | ✅ | ✅ | ✅ in-process |
| ChromaDB | ✅ | ✅ | ✅ | ✅ in-process |
| MongoDB  | ✅ | ✅ | ✅ | ✅ in-process |
| Pinecone | ✅ | ✅ | ✅ | ❌ — no scan-all API; native sparse-index hybrid is planned |

The in-process index follows the store: it is rebuilt as soon as the backend
reports a change (the row count; on DuckDB and pgvector also the newest
`seen_at`, which catches in-place edits) and refreshed in the background every
`hybrid_refresh_seconds` (default 30) as a bound on staleness for whatever
that cheap signal misses. In-process BM25 targets corpora up to a few million
chunks; above `hybrid_max_chunks` the keyword leg is skipped with a warning and
retrieval stays pure-vector. **Pinecone** cannot enumerate its vectors, so it has no
in-process hybrid — `hybrid: true` there fails fast at startup with that
explanation; native hybrid (a second sparse index) is planned. Native
server-side BM25 for the client-server backends (replacing the in-process
leg at larger scale) is planned as well.

## Observability

Three layers, all on by default or one config line away:

**In the chat UI.** The header shows *"indexed N s ago"* — the age of the
most recent write into the vector store. When you edit a source document,
you can watch the counter reset as the change lands.

**`GET /api/v1/stats`** on the API server: the backend in use, the number of
indexed chunks, and index freshness — a JSON one-liner for dashboards and
health checks, served without touching the indexer (it reads the vector
store, like every other query).

**Engine metrics (Prometheus).** The Pathway engine ships its own
observability server; serviette exposes it with one config line:

```yaml
indexer:
  monitoring_http_port: 20000
```

Every worker process then serves `GET /metrics` on
`127.0.0.1:(20000 + worker index)` — input/output latency gauges (i.e. the
indexing lag behind the sources) and per-operator row counters, straight
from the engine's dataflow. Point a Prometheus scrape at the worker ports
and you get per-stage throughput and freshness graphs with no extra code.

Logs from both processes go to stdout/stderr in plain text; `serviette up`
interleaves them with per-process prefixes.

## Security

The server listens on **localhost only** by default and ships no built-in
authentication — exposing it is an explicit decision: set `server.host:
0.0.0.0` and put an authenticating reverse proxy in front (a five-line
Caddy example lives in [docs](https://github.com/pathwaycom/serviette/blob/main/docs/README.md#security--exposing-the-server)).

## Requirements

- Python ≥ 3.10 (the minimum supported by Pathway).
- A free Pathway license key in `PATHWAY_LICENSE_KEY` —
  <https://pathway.com/framework/get-license>.

## Documentation

Full installation, the config wizard, configuration reference, persistence,
architecture and scaling notes live in **[docs/README.md](https://github.com/pathwaycom/serviette/blob/main/docs/README.md)**.

## Development

serviette runs on the released Pathway from PyPI (≥ 0.32.1 — the first
release with the vector-database connectors). From-scratch setup on a
fresh machine:

```bash
# 0. Prerequisites: Python >= 3.10 (3.12 recommended) and git.

# 1. serviette in its own virtualenv
git clone https://github.com/pathwaycom/serviette.git && cd serviette
python3.12 -m venv .venv
source .venv/bin/activate
pip install -e ".[dev,local]"

# 2. A (free) Pathway license: https://pathway.com/framework/get-license
export PATHWAY_LICENSE_KEY=...

# 3. Sanity check: zero-to-chat on the bundled corpus
serviette demo                        # -> http://localhost:8989
```

Notes:

- `serviette demo` materializes everything in a visible working directory:
  `./serviette-demo/docs` holds the corpus — a **toy example**, a handful of
  documents about a fictional company (Lumina Coffee Systems). Drop your own
  files there (PDF, DOCX, scans, …) while it runs and they are answerable
  within seconds.
- The demo indexes with one of two embedders — pick your trade-off:
  - **default, free & local** — needs `serviette[local]`, which pulls the
    PyTorch stack. Install it with
    `--extra-index-url https://download.pytorch.org/whl/cpu` to get the CPU
    build (~0.8 GB); without the flag pip takes PyTorch's default Linux
    wheel, which ships CUDA libraries whether or not you have an NVIDIA GPU
    (**~5 GB**, and the install is the slow part of the first run). Free at
    any corpus size afterwards.
  - **`--embedder openai`** — nothing to install, starts immediately, but
    every indexed token is billed to your `OPENAI_API_KEY`. Fine for the toy
    corpus and small folders; for a large collection, sit out the
    `serviette[local]` install and use the free embedder instead.
- Independently of the embedder, export `OPENAI_API_KEY` if you want real
  generated answers in `/rag` — without it the demo answers by quoting the
  retrieved snippets.

Running the test suites:

```bash
pytest -m "not slow"            # fast unit tests (no Pathway, no services)
pytest -m "slow and not integration"   # end-to-end indexer tests (spin up Pathway)
pytest -m integration          # real-database tests (see below)
pytest                         # everything
```

Per-backend clients install as extras — pick what you use:

```bash
pip install "serviette[qdrant]"      # also: pgvector, milvus, chroma, weaviate,
                                  #       pinecone, mongodb, local, gemini, all
```

### Integration tests (real databases)

**Every claimed backend has an integration test** running the same scenario
end-to-end against a real instance: index two documents with the real indexer,
retrieve through the production accessor (exact-text query must rank first
with cosine ~1.0), delete a file, re-index, and verify its vectors are gone
(snapshot semantics). The shared driver lives in `tests/integration_common.py`.

| Backend | Test | Real instance |
|---|---|---|
| DuckDB | `test_integration_duckdb.py` | embedded — runs everywhere |
| pgvector | `test_integration_pgvector.py` | `pgvector/pgvector` Docker container |
| Milvus | `test_integration_milvus.py` | embedded Milvus Lite engine; set `SERVIETTE_TEST_MILVUS_URI=http://host:19530` to run the same tests against a Milvus server (Lite has no growing/sealed segments, so it cannot catch stats-counting bugs) |
| Qdrant | `test_integration_qdrant.py` | `qdrant/qdrant` Docker container |
| ChromaDB | `test_integration_chroma.py` | `chromadb/chroma` Docker container |
| Weaviate | `test_integration_weaviate.py` | `semitechnologies/weaviate` Docker container |
| Pinecone | `test_integration_pinecone.py` | official `pinecone-local` emulator (Docker) |
| MongoDB | `test_integration_mongodb.py` | `mongodb-atlas-local` (mongod + mongot, real `$vectorSearch`) |

Containers are throwaway (`tests/dockerutil.py`, Docker CLI via subprocess, no
extra dependency) and host ports are **allocated dynamically** — tests never
assume a fixed localhost port is free or that a service is already running.
Each test skips automatically when Docker or its client library is missing.

## License

See [LICENSE](https://github.com/pathwaycom/serviette/blob/main/LICENSE).
