feat: add Pyversity integration

.github/labeler.yml

@@ -167,6 +167,11 @@ integration:pinecone:
       - any-glob-to-any-file: "integrations/pinecone/**/*"
       - any-glob-to-any-file: ".github/workflows/pinecone.yml"
 
+integration:pyversity:
+  - changed-files:
+      - any-glob-to-any-file: "integrations/pyversity/**/*"
+      - any-glob-to-any-file: ".github/workflows/pyversity.yml"
+
 integration:qdrant:
   - changed-files:
       - any-glob-to-any-file: "integrations/qdrant/**/*"

.github/workflows/pyversity.yml

@@ -0,0 +1,63 @@
+name: Test / pyversity
+
+on:
+  schedule:
+    - cron: "0 0 * * *"
+  pull_request:
+    paths:
+      - "integrations/pyversity/**"
+      - "!integrations/pyversity/*.md"
+      - ".github/workflows/pyversity.yml"
+
+defaults:
+  run:
+    working-directory: integrations/pyversity
+
+jobs:
+  run:
+    name: Python ${{ matrix.python-version }} on ${{ startsWith(matrix.os, 'macos-') && 'macOS' || startsWith(matrix.os, 'windows-') && 'Windows' || 'Linux' }}
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest]
+        python-version: ["3.10", "3.13"]
+
+    steps:
+      - uses: actions/checkout@v6
+
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v6
+        with:
+          python-version: ${{ matrix.python-version }}
+
+      - name: Install Hatch
+        run: pip install --upgrade hatch
+
+      - name: Lint
+        if: matrix.python-version == '3.10' && runner.os == 'Linux'
+        run: hatch run fmt-check && hatch run test:types
+
+      - name: Run tests
+        run: hatch run test:cov-retry
+
+      - name: Run unit tests with lowest direct dependencies
+        run: |
+          hatch run uv pip compile pyproject.toml --resolution lowest-direct --output-file requirements_lowest_direct.txt
+          hatch -e test env run -- uv pip install -r requirements_lowest_direct.txt
+          hatch run test:unit
+
+      - name: Nightly - run unit tests with Haystack main branch
+        if: github.event_name == 'schedule'
+        run: |
+          hatch env prune
+          hatch -e test env run -- uv pip install git+https://github.com/deepset-ai/haystack.git@main
+          hatch run test:unit
+
+      - name: Send event to Datadog for nightly failures
+        if: failure() && github.event_name == 'schedule'
+        uses: ./.github/actions/send_failure
+        with:
+          title: |
+            Core integrations nightly tests failure: ${{ github.workflow }}
+          api-key: ${{ secrets.CORE_DATADOG_API_KEY }}

README.md

@@ -59,6 +59,7 @@ Please check out our [Contribution Guidelines](CONTRIBUTING.md) for all the deta
 | [paddleocr-haystack](integrations/paddleocr/)                           | Converter                    | [![PyPI - Version](https://img.shields.io/pypi/v/paddleocr-haystack.svg)](https://pypi.org/project/paddleocr-haystack)                                   | [![Test / paddleocr](https://github.com/deepset-ai/haystack-core-integrations/actions/workflows/paddleocr.yml/badge.svg)](https://github.com/deepset-ai/haystack-core-integrations/actions/workflows/paddleocr.yml)                                        |
 | [pinecone-haystack](integrations/pinecone/)                             | Document Store              | [![PyPI - Version](https://img.shields.io/pypi/v/pinecone-haystack.svg?color=orange)](https://pypi.org/project/pinecone-haystack)                        | [![Test / pinecone](https://github.com/deepset-ai/haystack-core-integrations/actions/workflows/pinecone.yml/badge.svg)](https://github.com/deepset-ai/haystack-core-integrations/actions/workflows/pinecone.yml)                                           |
 | [pgvector-haystack](integrations/pgvector/)                             | Document Store              | [![PyPI - Version](https://img.shields.io/pypi/v/pgvector-haystack.svg?color=orange)](https://pypi.org/project/pgvector-haystack)                        | [![Test / pgvector](https://github.com/deepset-ai/haystack-core-integrations/actions/workflows/pgvector.yml/badge.svg)](https://github.com/deepset-ai/haystack-core-integrations/actions/workflows/pgvector.yml)                                           |
+| [pyversity-haystack](integrations/pyversity/)                           | Ranker                      | [![PyPI - Version](https://img.shields.io/pypi/v/pyversity-haystack.svg)](https://pypi.org/project/pyversity-haystack)                                   | [![Test / pyversity](https://github.com/deepset-ai/haystack-core-integrations/actions/workflows/pyversity.yml/badge.svg)](https://github.com/deepset-ai/haystack-core-integrations/actions/workflows/pyversity.yml)                                        |
 | [qdrant-haystack](integrations/qdrant/)                                 | Document Store              | [![PyPI - Version](https://img.shields.io/pypi/v/qdrant-haystack.svg?color=orange)](https://pypi.org/project/qdrant-haystack)                            | [![Test / qdrant](https://github.com/deepset-ai/haystack-core-integrations/actions/workflows/qdrant.yml/badge.svg)](https://github.com/deepset-ai/haystack-core-integrations/actions/workflows/qdrant.yml)                                                 |
 | [ragas-haystack](integrations/ragas/)                                   | Evaluator                   | [![PyPI - Version](https://img.shields.io/pypi/v/ragas-haystack.svg)](https://pypi.org/project/ragas-haystack)                                           | [![Test / ragas](https://github.com/deepset-ai/haystack-core-integrations/actions/workflows/ragas.yml/badge.svg)](https://github.com/deepset-ai/haystack-core-integrations/actions/workflows/ragas.yml)                                                    |
 | [snowflake-haystack](integrations/snowflake/)                           | Retriever                   | [![PyPI - Version](https://img.shields.io/pypi/v/snowflake-haystack.svg)](https://pypi.org/project/snowflake-haystack)                                   | [![Test / snowflake](https://github.com/deepset-ai/haystack-core-integrations/actions/workflows/snowflake.yml/badge.svg)](https://github.com/deepset-ai/haystack-core-integrations/actions/workflows/snowflake.yml)                                        |

integrations/pyversity/LICENSE.txt

@@ -0,0 +1,73 @@
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integrations/pyversity/README.md

@@ -0,0 +1,13 @@
+# pyversity-haystack
+
+[![PyPI - Version](https://img.shields.io/pypi/v/pyversity-haystack.svg)](https://pypi.org/project/pyversity-haystack)
+[![PyPI - Python Version](https://img.shields.io/pypi/pyversions/pyversity-haystack.svg)](https://pypi.org/project/pyversity-haystack)
+
+- [Changelog](https://github.com/deepset-ai/haystack-core-integrations/blob/main/integrations/pyversity/CHANGELOG.md)
+
+
+---
+
+## Contributing
+
+Refer to the general [Contribution Guidelines](https://github.com/deepset-ai/haystack-core-integrations/blob/main/CONTRIBUTING.md).

integrations/pyversity/examples/pipeline.py

@@ -0,0 +1,51 @@
+# SPDX-FileCopyrightText: 2026-present deepset GmbH <info@deepset.ai>
+#
+# SPDX-License-Identifier: Apache-2.0
+
+from haystack import Document, Pipeline
+from haystack.components.embedders import SentenceTransformersDocumentEmbedder, SentenceTransformersTextEmbedder
+from haystack.components.retrievers import InMemoryEmbeddingRetriever
+from haystack.document_stores.in_memory import InMemoryDocumentStore
+from pyversity import Strategy
+
+from haystack_integrations.components.rankers.pyversity import PyversityRanker
+
+# Index documents
+document_store = InMemoryDocumentStore()
+
+raw_documents = [
+    Document(content="Paris is the capital of France."),
+    Document(content="The Eiffel Tower is located in Paris."),
+    Document(content="Berlin is the capital of Germany."),
+    Document(content="The Brandenburg Gate is in Berlin."),
+    Document(content="France borders Spain to the south."),
+    Document(content="The Louvre is the world's largest art museum and is in Paris."),
+    Document(content="Munich is the capital of Bavaria."),
+    Document(content="The Rhine river flows through Germany and France."),
+]
+
+doc_embedder = SentenceTransformersDocumentEmbedder()
+documents_with_embeddings = doc_embedder.run(raw_documents)["documents"]
+document_store.write_documents(documents_with_embeddings)
+
+# Build pipeline
+pipeline = Pipeline()
+pipeline.add_component("text_embedder", SentenceTransformersTextEmbedder())
+pipeline.add_component(
+    "retriever",
+    InMemoryEmbeddingRetriever(document_store=document_store, top_k=6, return_embedding=True),
+)
+pipeline.add_component("reranker", PyversityRanker(top_k=3, strategy=Strategy.MMR, diversity=0.7))
+
+pipeline.connect("text_embedder.embedding", "retriever.query_embedding")
+pipeline.connect("retriever.documents", "reranker.documents")
+
+# Run
+result = pipeline.run({"text_embedder": {"text": "What are the famous landmarks in France?"}})
+
+for doc in result["reranker"]["documents"]:
+    print(f"{doc.score:.4f}  {doc.content}")
+
+# 0.1846  Paris is the capital of France.
+# -0.1647  The Rhine river flows through Germany and France.
+# -0.1775  The Brandenburg Gate is in Berlin.