diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7160ea0f..47256b91 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -25,6 +25,7 @@
 
 ### Removed
 
+- `haiku.rag.config.Config`, the eagerly loaded configuration instance. Use `get_config()` for the current global config, or pass an `AppConfig`. Every internal default (`get_embedder`, `get_converter`, `get_chunker`, `get_reranker`, `embed_chunks`, `HaikuRAG`, `Store`, `HaikuRAGApp`, `create_mcp_server`) now takes `config: AppConfig | None = None` and resolves it per call, so `set_config()` reaches them. `RerankerBase._model` no longer defaults to the configured reranker name; `CohereReranker` takes its model name as an argument.
 - `wix` evaluation dataset and its reference config `evaluations/configs/wix.yaml`.
 
 ### Fixed
diff --git a/app/backend/main.py b/app/backend/main.py
index 109fb659..ec67be0b 100644
--- a/app/backend/main.py
+++ b/app/backend/main.py
@@ -44,16 +44,16 @@ logger = logging.getLogger(__name__)
 config_path = Path("/app/haiku.rag.yaml")
 if config_path.exists():
     yaml_data = load_yaml_config(config_path)
-    Config = AppConfig.model_validate(yaml_data)
+    config = AppConfig.model_validate(yaml_data)
 else:
-    Config = AppConfig()
+    config = AppConfig()
 
 # Get DB path from environment
 db_path_str = os.getenv("DB_PATH", "haiku_rag.lancedb")
 db_path = Path(db_path_str)
 
 logger.info(f"Database path: {db_path}")
-logger.info(f"QA Provider: {Config.qa.model.provider}, Model: {Config.qa.model.name}")
+logger.info(f"QA Provider: {config.qa.model.provider}, Model: {config.qa.model.name}")
 
 # Only HaikuRAG client is a singleton (expensive to create)
 _client: HaikuRAG | None = None
@@ -71,7 +71,7 @@ async def get_client() -> HaikuRAG:
     if _client is None:
         async with _client_lock:
             if _client is None:
-                client = HaikuRAG(db_path=db_path, config=Config, create=True)
+                client = HaikuRAG(db_path=db_path, config=config, create=True)
                 await client.__aenter__()
                 _client = client
     return _client
@@ -82,10 +82,10 @@ class AppDeps:
     state: dict[str, Any] = field(default_factory=dict)
 
 
-capability = create_capability(db_path=db_path, config=Config, defer_loading=False)
+capability = create_capability(db_path=db_path, config=config, defer_loading=False)
 
 agent = Agent(
-    get_model(Config.qa.model, Config),
+    get_model(config.qa.model, config),
     instructions=AGENT_PREAMBLE,
     # Conversations here are multi-turn, so earlier questions are reduced to the
     # evidence they cited rather than carried whole, and every answer declares
@@ -136,8 +136,8 @@ async def health_check(_: Request) -> JSONResponse:
     return JSONResponse(
         {
             "status": "healthy",
-            "qa_provider": Config.qa.model.provider,
-            "qa_model": Config.qa.model.name,
+            "qa_provider": config.qa.model.provider,
+            "qa_model": config.qa.model.name,
             "db_path": str(db_path),
             "db_exists": db_path.exists(),
         }
diff --git a/haiku_rag_slim/haiku/rag/app.py b/haiku_rag_slim/haiku/rag/app.py
index 47866555..546f9e17 100644
--- a/haiku_rag_slim/haiku/rag/app.py
+++ b/haiku_rag_slim/haiku/rag/app.py
@@ -16,7 +16,7 @@ from rich.progress import (
 )
 
 from haiku.rag.client import HaikuRAG, RebuildMode
-from haiku.rag.config import AppConfig, Config
+from haiku.rag.config import AppConfig, get_config
 from haiku.rag.mcp import create_mcp_server
 from haiku.rag.store.models.chunk import SearchType
 from haiku.rag.store.models.document import Document
@@ -33,11 +33,11 @@ class HaikuRAGApp:  # pragma: no cover
     def __init__(
         self,
         db_path: Path,
-        config: AppConfig = Config,
+        config: AppConfig | None = None,
         read_only: bool = False,
     ):
         self.db_path = db_path
-        self.config = config
+        self.config = config if config is not None else get_config()
         self.read_only = read_only
         self.console = Console()
 
diff --git a/haiku_rag_slim/haiku/rag/chunkers/__init__.py b/haiku_rag_slim/haiku/rag/chunkers/__init__.py
index 38d43f22..256fd704 100644
--- a/haiku_rag_slim/haiku/rag/chunkers/__init__.py
+++ b/haiku_rag_slim/haiku/rag/chunkers/__init__.py
@@ -1,16 +1,16 @@
 """Document chunker abstraction for haiku.rag."""
 
 from haiku.rag.chunkers.base import DocumentChunker
-from haiku.rag.config import AppConfig, Config
+from haiku.rag.config import AppConfig, get_config
 
 __all__ = ["DocumentChunker", "get_chunker"]
 
 
-def get_chunker(config: AppConfig = Config) -> DocumentChunker:
+def get_chunker(config: AppConfig | None = None) -> DocumentChunker:
     """Get a document chunker instance based on configuration.
 
     Args:
-        config: Configuration to use. Defaults to global Config.
+        config: Configuration to use. Defaults to the current global config.
 
     Returns:
         DocumentChunker instance configured according to the config.
@@ -18,6 +18,7 @@ def get_chunker(config: AppConfig = Config) -> DocumentChunker:
     Raises:
         ValueError: If the chunker provider is not recognized.
     """
+    config = config if config is not None else get_config()
     if config.processing.chunker == "docling-local":
         from haiku.rag.chunkers.docling_local import DoclingLocalChunker
 
diff --git a/haiku_rag_slim/haiku/rag/chunkers/docling_local.py b/haiku_rag_slim/haiku/rag/chunkers/docling_local.py
index 85b7f690..5691c839 100644
--- a/haiku_rag_slim/haiku/rag/chunkers/docling_local.py
+++ b/haiku_rag_slim/haiku/rag/chunkers/docling_local.py
@@ -3,7 +3,7 @@ from functools import cache
 from typing import TYPE_CHECKING, cast
 
 from haiku.rag.chunkers.base import DocumentChunker
-from haiku.rag.config import AppConfig, Config
+from haiku.rag.config import AppConfig, get_config
 from haiku.rag.store.models.chunk import Chunk, ChunkMetadata
 
 if TYPE_CHECKING:
@@ -68,7 +68,7 @@ class DoclingLocalChunker(DocumentChunker):
         config: Application configuration.
     """
 
-    def __init__(self, config: AppConfig = Config):
+    def __init__(self, config: AppConfig | None = None):
         from docling_core.transforms.chunker.hierarchical_chunker import (
             HierarchicalChunker,
         )
@@ -77,10 +77,10 @@ class DoclingLocalChunker(DocumentChunker):
             HuggingFaceTokenizer,
         )
 
-        self.config = config
-        self.chunk_size = config.processing.chunk_size
-        self.chunker_type = config.processing.chunker_type
-        self.tokenizer_name = config.processing.chunking_tokenizer
+        self.config = config if config is not None else get_config()
+        self.chunk_size = self.config.processing.chunk_size
+        self.chunker_type = self.config.processing.chunker_type
+        self.tokenizer_name = self.config.processing.chunking_tokenizer
 
         if self.chunker_type == "hybrid":
             hf_tokenizer = _get_tokenizer(self.tokenizer_name)
@@ -88,16 +88,16 @@ class DoclingLocalChunker(DocumentChunker):
                 tokenizer=hf_tokenizer, max_tokens=self.chunk_size
             )
             serializer_provider = _create_markdown_serializer_provider(
-                use_markdown_tables=config.processing.chunking_use_markdown_tables
+                use_markdown_tables=self.config.processing.chunking_use_markdown_tables
             )
             self.chunker = HybridChunker(
                 tokenizer=tokenizer,
-                merge_peers=config.processing.chunking_merge_peers,
+                merge_peers=self.config.processing.chunking_merge_peers,
                 serializer_provider=serializer_provider,
             )
         elif self.chunker_type == "hierarchical":
             serializer_provider = _create_markdown_serializer_provider(
-                use_markdown_tables=config.processing.chunking_use_markdown_tables
+                use_markdown_tables=self.config.processing.chunking_use_markdown_tables
             )
             self.chunker = HierarchicalChunker(serializer_provider=serializer_provider)
         else:
diff --git a/haiku_rag_slim/haiku/rag/chunkers/docling_serve.py b/haiku_rag_slim/haiku/rag/chunkers/docling_serve.py
index 6398692b..842ec439 100644
--- a/haiku_rag_slim/haiku/rag/chunkers/docling_serve.py
+++ b/haiku_rag_slim/haiku/rag/chunkers/docling_serve.py
@@ -4,7 +4,7 @@ from io import BytesIO
 from typing import TYPE_CHECKING
 
 from haiku.rag.chunkers.base import DocumentChunker
-from haiku.rag.config import AppConfig, Config
+from haiku.rag.config import AppConfig, get_config
 from haiku.rag.providers.docling_serve import DoclingServeClient
 from haiku.rag.store.models.chunk import Chunk, ChunkMetadata
 
@@ -54,10 +54,12 @@ class DoclingServeChunker(DocumentChunker):
         config: Application configuration containing docling-serve settings.
     """
 
-    def __init__(self, config: AppConfig = Config):
-        self.config = config
-        self.client = DoclingServeClient.from_config(config.providers.docling_serve)
-        self.chunker_type = config.processing.chunker_type
+    def __init__(self, config: AppConfig | None = None):
+        self.config = config if config is not None else get_config()
+        self.client = DoclingServeClient.from_config(
+            self.config.providers.docling_serve
+        )
+        self.chunker_type = self.config.processing.chunker_type
 
     def _build_chunking_data(self) -> dict[str, str | list[str]]:
         """Build form data for chunking request."""
diff --git a/haiku_rag_slim/haiku/rag/client/__init__.py b/haiku_rag_slim/haiku/rag/client/__init__.py
index 278e3627..308987b5 100644
--- a/haiku_rag_slim/haiku/rag/client/__init__.py
+++ b/haiku_rag_slim/haiku/rag/client/__init__.py
@@ -15,7 +15,7 @@ from urllib.parse import urlparse
 import httpx
 
 from haiku.rag.client.documents import DocumentImport
-from haiku.rag.config import AppConfig, Config
+from haiku.rag.config import AppConfig, get_config
 from haiku.rag.converters import get_converter
 from haiku.rag.reranking import get_reranker
 from haiku.rag.store.engine import Store
@@ -67,7 +67,7 @@ class HaikuRAG:
     def __init__(
         self,
         db_path: Path | None = None,
-        config: AppConfig = Config,
+        config: AppConfig | None = None,
         skip_validation: bool = False,
         create: bool = False,
         read_only: bool = False,
@@ -76,12 +76,12 @@ class HaikuRAG:
 
         Args:
             db_path: Path to the database file. If None, uses config.storage.data_dir.
-            config: Configuration to use. Defaults to global Config.
+            config: Configuration to use. Defaults to the current global config.
             skip_validation: Whether to skip configuration validation on database load.
             create: Whether to create the database if it doesn't exist.
             read_only: Whether to open the database in read-only mode.
         """
-        self._config = config
+        self._config = config if config is not None else get_config()
         if db_path is None:
             db_path = self._config.storage.data_dir / "haiku.rag.lancedb"
 
diff --git a/haiku_rag_slim/haiku/rag/config/__init__.py b/haiku_rag_slim/haiku/rag/config/__init__.py
index c2b79f0d..1ba11f79 100644
--- a/haiku_rag_slim/haiku/rag/config/__init__.py
+++ b/haiku_rag_slim/haiku/rag/config/__init__.py
@@ -36,7 +36,6 @@ from haiku.rag.config.models import (
 )
 
 __all__ = [
-    "Config",
     "APIConfig",
     "AppConfig",
     "CircuitBreakerConfig",
@@ -78,7 +77,7 @@ _config: AppConfig | None = None
 
 
 def _load_default_config() -> AppConfig:
-    """Load config from default locations (used at import time)."""
+    """Load config from the default locations."""
     config_path = find_config_file(None)
     if config_path:
         yaml_data = load_yaml_config(config_path)
@@ -93,12 +92,8 @@ def set_config(config: AppConfig) -> None:
 
 
 def get_config() -> AppConfig:
-    """Get the current config instance."""
+    """Get the current config instance, loading it on first use."""
     global _config
     if _config is None:
         _config = _load_default_config()
     return _config
-
-
-# Legacy compatibility - Config is the default instance
-Config = _load_default_config()
diff --git a/haiku_rag_slim/haiku/rag/converters/__init__.py b/haiku_rag_slim/haiku/rag/converters/__init__.py
index 1ec4c4d3..82edf647 100644
--- a/haiku_rag_slim/haiku/rag/converters/__init__.py
+++ b/haiku_rag_slim/haiku/rag/converters/__init__.py
@@ -1,16 +1,16 @@
 """Document converter abstraction for haiku.rag."""
 
-from haiku.rag.config import AppConfig, Config
+from haiku.rag.config import AppConfig, get_config
 from haiku.rag.converters.base import DocumentConverter
 
 __all__ = ["DocumentConverter", "get_converter"]
 
 
-def get_converter(config: AppConfig = Config) -> DocumentConverter:
+def get_converter(config: AppConfig | None = None) -> DocumentConverter:
     """Get a document converter instance based on configuration.
 
     Args:
-        config: Configuration to use. Defaults to global Config.
+        config: Configuration to use. Defaults to the current global config.
 
     Returns:
         DocumentConverter instance configured according to the config.
@@ -18,6 +18,7 @@ def get_converter(config: AppConfig = Config) -> DocumentConverter:
     Raises:
         ValueError: If the converter provider is not recognized.
     """
+    config = config if config is not None else get_config()
     if config.processing.converter == "docling-local":
         from haiku.rag.converters.docling_local import DoclingLocalConverter
 
diff --git a/haiku_rag_slim/haiku/rag/embeddings/__init__.py b/haiku_rag_slim/haiku/rag/embeddings/__init__.py
index 2b548745..2df7860c 100644
--- a/haiku_rag_slim/haiku/rag/embeddings/__init__.py
+++ b/haiku_rag_slim/haiku/rag/embeddings/__init__.py
@@ -7,7 +7,7 @@ from pydantic_ai.embeddings.openai import OpenAIEmbeddingModel
 from pydantic_ai.providers.ollama import OllamaProvider
 from pydantic_ai.providers.openai import OpenAIProvider
 
-from haiku.rag.config import AppConfig, Config
+from haiku.rag.config import AppConfig, get_config
 
 if TYPE_CHECKING:
     from PIL import Image as PILImage
@@ -118,7 +118,9 @@ def contextualize(chunks: list["Chunk"]) -> list[str]:
 
 
 async def embed_chunks(
-    chunks: list["Chunk"], embedder: "EmbedderWrapper", config: AppConfig = Config
+    chunks: list["Chunk"],
+    embedder: "EmbedderWrapper",
+    config: AppConfig | None = None,
 ) -> list["Chunk"]:
     """Generate embeddings for chunks, dispatching text vs picture variants.
 
@@ -127,6 +129,7 @@ async def embed_chunks(
     are routed through ``embed_images`` and require a multimodal embedder.
     Vectors land in the original chunk order.
     """
+    config = config if config is not None else get_config()
     if not chunks:
         return []
 
@@ -181,15 +184,16 @@ async def embed_chunks(
     ]
 
 
-def get_embedder(config: AppConfig = Config) -> EmbedderWrapper:
+def get_embedder(config: AppConfig | None = None) -> EmbedderWrapper:
     """Factory function to get the appropriate embedder based on the configuration.
 
     Args:
-        config: Configuration to use. Defaults to global Config.
+        config: Configuration to use. Defaults to the current global config.
 
     Returns:
         An embedder instance configured according to the config.
     """
+    config = config if config is not None else get_config()
     embedding_model = config.embeddings.model
     provider = embedding_model.provider
     model_name = embedding_model.name
diff --git a/haiku_rag_slim/haiku/rag/mcp.py b/haiku_rag_slim/haiku/rag/mcp.py
index a8a44b50..16e97d29 100644
--- a/haiku_rag_slim/haiku/rag/mcp.py
+++ b/haiku_rag_slim/haiku/rag/mcp.py
@@ -7,7 +7,7 @@ from typing import Any
 from fastmcp import FastMCP
 
 from haiku.rag.client import HaikuRAG
-from haiku.rag.config import AppConfig, Config
+from haiku.rag.config import AppConfig, get_config
 from haiku.rag.store.models import Document, SearchResult
 from haiku.rag.tools.document import DocumentInfo
 from haiku.rag.utils import format_citations
@@ -22,7 +22,7 @@ def _decode_images(images_base64: list[str] | None) -> list[bytes] | None:
 
 
 def create_mcp_server(
-    db_path: Path, config: AppConfig = Config, read_only: bool = False
+    db_path: Path, config: AppConfig | None = None, read_only: bool = False
 ) -> FastMCP:
     """Create an MCP server with the specified database path.
 
@@ -31,6 +31,7 @@ def create_mcp_server(
         config: Configuration to use.
         read_only: If True, write tools (add_document_*, delete_document) are not registered.
     """
+    config = config if config is not None else get_config()
     client: HaikuRAG | None = None
     stack = AsyncExitStack()
     client_lock = asyncio.Lock()
diff --git a/haiku_rag_slim/haiku/rag/reranking/__init__.py b/haiku_rag_slim/haiku/rag/reranking/__init__.py
index e02e64db..eca838cc 100644
--- a/haiku_rag_slim/haiku/rag/reranking/__init__.py
+++ b/haiku_rag_slim/haiku/rag/reranking/__init__.py
@@ -1,10 +1,11 @@
-from haiku.rag.config import AppConfig, Config
+from haiku.rag.config import AppConfig, get_config
 from haiku.rag.reranking.base import RerankerBase
 
 
-def get_reranker(config: AppConfig = Config) -> RerankerBase | None:
+def get_reranker(config: AppConfig | None = None) -> RerankerBase | None:
     """Build the configured reranker, or None if reranking is disabled or its
     optional dependency is not installed."""
+    config = config if config is not None else get_config()
     model = config.reranking.model
     if model is None:
         return None
@@ -16,7 +17,7 @@ def get_reranker(config: AppConfig = Config) -> RerankerBase | None:
         if model.provider == "cohere":
             from haiku.rag.reranking.cohere import CohereReranker
 
-            return CohereReranker()
+            return CohereReranker(model.name)
 
         if model.provider == "vllm":
             if not model.base_url:
diff --git a/haiku_rag_slim/haiku/rag/reranking/base.py b/haiku_rag_slim/haiku/rag/reranking/base.py
index 703ed912..61aa092f 100644
--- a/haiku_rag_slim/haiku/rag/reranking/base.py
+++ b/haiku_rag_slim/haiku/rag/reranking/base.py
@@ -1,9 +1,8 @@
-from haiku.rag.config import Config
 from haiku.rag.store.models.chunk import Chunk
 
 
 class RerankerBase:
-    _model: str | None = Config.reranking.model.name if Config.reranking.model else None
+    _model: str | None = None
 
     async def rerank(
         self, query: str, chunks: list[Chunk], top_n: int = 10
diff --git a/haiku_rag_slim/haiku/rag/reranking/cohere.py b/haiku_rag_slim/haiku/rag/reranking/cohere.py
index 25571bd7..29442052 100644
--- a/haiku_rag_slim/haiku/rag/reranking/cohere.py
+++ b/haiku_rag_slim/haiku/rag/reranking/cohere.py
@@ -10,7 +10,8 @@ except ImportError as e:  # pragma: no cover
 
 
 class CohereReranker(RerankerBase):  # pragma: no cover
-    def __init__(self):
+    def __init__(self, model: str | None = None):
+        self._model = model
         # Cohere SDK reads CO_API_KEY from environment by default
         self._client = cohere.AsyncClientV2()
 
diff --git a/haiku_rag_slim/haiku/rag/store/engine.py b/haiku_rag_slim/haiku/rag/store/engine.py
index c40dbbdd..240cfe13 100644
--- a/haiku_rag_slim/haiku/rag/store/engine.py
+++ b/haiku_rag_slim/haiku/rag/store/engine.py
@@ -18,7 +18,7 @@ from lancedb.pydantic import LanceModel, Vector
 from packaging.version import parse
 from pydantic import BaseModel, Field
 
-from haiku.rag.config import AppConfig, Config
+from haiku.rag.config import AppConfig, get_config
 from haiku.rag.embeddings import get_embedder
 from haiku.rag.store.exceptions import MigrationRequiredError, ReadOnlyError
 
@@ -497,14 +497,14 @@ class Store:
     def __init__(
         self,
         db_path: Path,
-        config: AppConfig = Config,
+        config: AppConfig | None = None,
         skip_validation: bool = False,
         create: bool = False,
         read_only: bool = False,
         skip_migration_check: bool = False,
     ):
         self.db_path: Path = db_path
-        self._config = config
+        self._config = config if config is not None else get_config()
         self._read_only = read_only
         self._create = create
         self._skip_validation = skip_validation
diff --git a/haiku_rag_slim/haiku/rag/utils.py b/haiku_rag_slim/haiku/rag/utils.py
index 98812deb..cac1896a 100644
--- a/haiku_rag_slim/haiku/rag/utils.py
+++ b/haiku_rag_slim/haiku/rag/utils.py
@@ -119,7 +119,7 @@ def get_model(
 
     Args:
         model_config: ModelConfig with provider, model, and settings
-        app_config: AppConfig for provider base URLs (defaults to global Config)
+        app_config: AppConfig for provider base URLs (defaults to the current global config)
 
     Returns:
         A configured model instance
@@ -129,9 +129,9 @@ def get_model(
     from pydantic_ai.providers.openai import OpenAIProvider
 
     if app_config is None:
-        from haiku.rag.config import Config
+        from haiku.rag.config import get_config
 
-        app_config = Config
+        app_config = get_config()
 
     provider = model_config.provider
     model = model_config.name
diff --git a/tests/test_chunk.py b/tests/test_chunk.py
index d052299f..aa5f503a 100644
--- a/tests/test_chunk.py
+++ b/tests/test_chunk.py
@@ -1,7 +1,7 @@
 import pytest
 
 from haiku.rag.client import HaikuRAG
-from haiku.rag.config import Config
+from haiku.rag.config import get_config
 from haiku.rag.store.models.chunk import Chunk, ChunkMetadata, SearchResult
 from tests.conftest import capture_logs
 
@@ -11,7 +11,9 @@ async def test_chunk_repository_operations(
     qa_corpus: list[dict[str, str]], temp_db_path
 ):
     """Test ChunkRepository operations."""
-    async with HaikuRAG(db_path=temp_db_path, config=Config, create=True) as client:
+    async with HaikuRAG(
+        db_path=temp_db_path, config=get_config(), create=True
+    ) as client:
         # Get the first document from the corpus
         first_doc = qa_corpus[0]
         document_text = first_doc["document_extracted"]
@@ -52,7 +54,9 @@ async def test_chunk_repository_pagination(
     qa_corpus: list[dict[str, str]], temp_db_path
 ):
     """Test ChunkRepository pagination with get_by_document_id and count_by_document_id."""
-    async with HaikuRAG(db_path=temp_db_path, config=Config, create=True) as client:
+    async with HaikuRAG(
+        db_path=temp_db_path, config=get_config(), create=True
+    ) as client:
         # Get the first document from the corpus (should produce multiple chunks)
         first_doc = qa_corpus[0]
         document_text = first_doc["document_extracted"]
@@ -443,7 +447,9 @@ async def test_chunk_content_fts(temp_db_path, metadata, content, expected_conte
     """content_fts holds the contextualized content while content stays raw."""
     from haiku.rag.embeddings import get_embedder
 
-    async with HaikuRAG(db_path=temp_db_path, config=Config, create=True) as client:
+    async with HaikuRAG(
+        db_path=temp_db_path, config=get_config(), create=True
+    ) as client:
         chunk = Chunk(
             document_id="test-doc",
             content=content,
@@ -451,7 +457,7 @@ async def test_chunk_content_fts(temp_db_path, metadata, content, expected_conte
             order=0,
         )
 
-        embedder = get_embedder(Config)
+        embedder = get_embedder(get_config())
         embedding = (await embedder.embed_documents([chunk.content]))[0]
         chunk.embedding = embedding
 
@@ -477,7 +483,9 @@ async def test_ensure_fts_index_warns_on_failure(temp_db_path):
 
     from haiku.rag.store.repositories import chunk as chunk_module
 
-    async with HaikuRAG(db_path=temp_db_path, config=Config, create=True) as client:
+    async with HaikuRAG(
+        db_path=temp_db_path, config=get_config(), create=True
+    ) as client:
         repo = client.chunk_repository
 
         async def _boom(*_args, **_kwargs):
@@ -497,7 +505,9 @@ async def test_chunk_repository_get_by_id_and_list_all_pagination(
     qa_corpus: list[dict[str, str]], temp_db_path
 ):
     """get_by_id resolves a stored chunk; list_all honours limit and offset."""
-    async with HaikuRAG(db_path=temp_db_path, config=Config, create=True) as client:
+    async with HaikuRAG(
+        db_path=temp_db_path, config=get_config(), create=True
+    ) as client:
         # A corpus document is long enough to chunk more than once, which is
         # what makes the offset assertion below meaningful.
         doc = await client.create_document(content=qa_corpus[0]["document_extracted"])
@@ -531,7 +541,9 @@ async def test_chunk_repository_get_by_id_and_list_all_pagination(
 @pytest.mark.vcr()
 async def test_chunk_search_returns_empty_for_blank_query(temp_db_path):
     """A blank query with no precomputed vector short-circuits before searching."""
-    async with HaikuRAG(db_path=temp_db_path, config=Config, create=True) as client:
+    async with HaikuRAG(
+        db_path=temp_db_path, config=get_config(), create=True
+    ) as client:
         await client.create_document(content="Searchable body about elections.")
 
         # Positive control: the corpus is non-empty, so [] is a real decision
@@ -543,7 +555,9 @@ async def test_chunk_search_returns_empty_for_blank_query(temp_db_path):
 @pytest.mark.vcr()
 async def test_chunk_search_with_precomputed_vector_skips_text_query(temp_db_path):
     """The image-as-query path searches vector-only using a stored embedding."""
-    async with HaikuRAG(db_path=temp_db_path, config=Config, create=True) as client:
+    async with HaikuRAG(
+        db_path=temp_db_path, config=get_config(), create=True
+    ) as client:
         doc = await client.create_document(content="Vector-only search target.")
         assert doc.id is not None
 
@@ -557,7 +571,9 @@ async def test_chunk_search_with_precomputed_vector_skips_text_query(temp_db_pat
 
 
 async def test_get_chunk_ids_by_self_ref_grouped_without_documents(temp_db_path):
-    async with HaikuRAG(db_path=temp_db_path, config=Config, create=True) as client:
+    async with HaikuRAG(
+        db_path=temp_db_path, config=get_config(), create=True
+    ) as client:
         assert await client.chunk_repository.get_chunk_ids_by_self_ref_grouped([]) == {}
 
 
@@ -565,7 +581,9 @@ async def test_process_search_results_rejects_unknown_score_column(temp_db_path)
     """A result frame with no recognised score column is a programming error."""
     import pandas as pd
 
-    async with HaikuRAG(db_path=temp_db_path, config=Config, create=True) as client:
+    async with HaikuRAG(
+        db_path=temp_db_path, config=get_config(), create=True
+    ) as client:
 
         class _Frame:
             async def to_pandas(self):
diff --git a/tests/test_chunker.py b/tests/test_chunker.py
index c39f5831..b7dfa9fa 100644
--- a/tests/test_chunker.py
+++ b/tests/test_chunker.py
@@ -7,7 +7,7 @@ from transformers import AutoTokenizer
 from haiku.rag.chunkers import get_chunker
 from haiku.rag.chunkers.docling_local import DoclingLocalChunker
 from haiku.rag.chunkers.docling_serve import DoclingServeChunker
-from haiku.rag.config import AppConfig, Config
+from haiku.rag.config import AppConfig, get_config
 from haiku.rag.converters import get_converter
 
 
@@ -23,7 +23,7 @@ async def test_local_chunker(qa_corpus: list[dict[str, str]]):
     doc_text = qa_corpus[0]["document_extracted"]
 
     # Convert text to DoclingDocument
-    converter = get_converter(Config)
+    converter = get_converter(get_config())
     doc = await converter.convert_text(doc_text, name="test.md")
 
     chunks = await chunker.chunk(doc)
@@ -79,7 +79,7 @@ async def test_local_chunker_runs_off_event_loop_thread():
         called_from.append(threading.current_thread())
         return original(document)
 
-    converter = get_converter(Config)
+    converter = get_converter(get_config())
     doc = await converter.convert_text("# Hello\n\nWorld", name="test.md")
 
     with patch.object(DoclingLocalChunker, "_chunk_sync", recording_chunk_sync):
@@ -149,7 +149,7 @@ async def test_local_chunker_hierarchical(qa_corpus: list[dict[str, str]]):
     chunker = DoclingLocalChunker(config)
 
     doc_text = qa_corpus[0]["document_extracted"]
-    converter = get_converter(Config)
+    converter = get_converter(get_config())
     doc = await converter.convert_text(doc_text, name="test.md")
 
     chunks = await chunker.chunk(doc)
@@ -180,7 +180,7 @@ async def test_local_chunker_markdown_tables():
 | Value D  | Value E  |
 """
 
-    converter = get_converter(Config)
+    converter = get_converter(get_config())
     doc = await converter.convert_text(markdown_with_table, name="test.md")
 
     # Test with markdown tables enabled
@@ -222,7 +222,7 @@ Second paragraph.
 
 Third paragraph.
 """
-    converter = get_converter(Config)
+    converter = get_converter(get_config())
     doc = await converter.convert_text(sample_md, name="test.md")
 
     chunker = DoclingLocalChunker()
@@ -249,7 +249,7 @@ Here is some background information.
 |----------|----------|
 | Value 1  | Value 2  |
 """
-    converter = get_converter(Config)
+    converter = get_converter(get_config())
     doc = await converter.convert_text(sample_md, name="test.md")
 
     chunker = DoclingLocalChunker()
@@ -347,7 +347,7 @@ class TestDoclingServeChunker:
         mock_client_class.return_value.__aenter__.return_value = mock_client
 
         # Create a simple document
-        converter = get_converter(Config)
+        converter = get_converter(get_config())
         doc = await converter.convert_text("# Test\n\nContent", name="test.md")
 
         chunks = await chunker.chunk(doc)
@@ -371,7 +371,7 @@ class TestDoclingServeChunker:
         mock_client.get = AsyncMock(side_effect=[poll_resp, result_resp])
         mock_client_class.return_value.__aenter__.return_value = mock_client
 
-        converter = get_converter(Config)
+        converter = get_converter(get_config())
         doc = await converter.convert_text("# Test", name="test.md")
         await chunker.chunk(doc)
 
@@ -394,7 +394,7 @@ class TestDoclingServeChunker:
         mock_client.get = AsyncMock(side_effect=[poll_resp, result_resp])
         mock_client_class.return_value.__aenter__.return_value = mock_client
 
-        converter = get_converter(Config)
+        converter = get_converter(get_config())
         doc = await converter.convert_text("# Test", name="test.md")
         await chunker.chunk(doc)
 
@@ -422,7 +422,7 @@ class TestDoclingServeChunker:
         mock_client.get = AsyncMock(side_effect=[poll_resp, result_resp])
         mock_client_class.return_value.__aenter__.return_value = mock_client
 
-        converter = get_converter(Config)
+        converter = get_converter(get_config())
         doc = await converter.convert_text("# Test", name="test.md")
         await chunker.chunk(doc)
 
@@ -453,7 +453,7 @@ class TestDoclingServeChunker:
         mock_client.get = AsyncMock(side_effect=[poll_resp, result_resp])
         mock_client_class.return_value.__aenter__.return_value = mock_client
 
-        converter = get_converter(Config)
+        converter = get_converter(get_config())
         doc = await converter.convert_text("# Test", name="test.md")
         await chunker.chunk(doc)
 
@@ -476,7 +476,7 @@ class TestDoclingServeChunker:
         mock_client.post.side_effect = httpx.ConnectError("Connection failed")
         mock_client_class.return_value.__aenter__.return_value = mock_client
 
-        converter = get_converter(Config)
+        converter = get_converter(get_config())
         doc = await converter.convert_text("# Test", name="test.md")
 
         with pytest.raises(httpx.ConnectError):
@@ -492,7 +492,7 @@ class TestDoclingServeChunker:
         mock_client.post.side_effect = httpx.TimeoutException("Timeout")
         mock_client_class.return_value.__aenter__.return_value = mock_client
 
-        converter = get_converter(Config)
+        converter = get_converter(get_config())
         doc = await converter.convert_text("# Test", name="test.md")
 
         with pytest.raises(httpx.TimeoutException):
@@ -517,7 +517,7 @@ class TestDoclingServeChunker:
         mock_client.post.return_value = mock_response
         mock_client_class.return_value.__aenter__.return_value = mock_client
 
-        converter = get_converter(Config)
+        converter = get_converter(get_config())
         doc = await converter.convert_text("# Test", name="test.md")
 
         with pytest.raises(httpx.HTTPStatusError) as exc_info:
@@ -545,7 +545,7 @@ class TestDoclingServeChunker:
         mock_client.get = AsyncMock(side_effect=[poll_resp, result_resp])
         mock_client_class.return_value.__aenter__.return_value = mock_client
 
-        converter = get_converter(Config)
+        converter = get_converter(get_config())
         doc = await converter.convert_text("# Test", name="test.md")
 
         with pytest.raises(ValueError, match="Chunking failed"):
@@ -574,7 +574,7 @@ class TestDoclingServeChunker:
         mock_client.get = AsyncMock(side_effect=[poll_resp, result_resp])
         mock_client_class.return_value.__aenter__.return_value = mock_client
 
-        converter = get_converter(Config)
+        converter = get_converter(get_config())
         doc = await converter.convert_text("# Test", name="test.md")
 
         chunks = await chunker.chunk(doc)
@@ -612,7 +612,7 @@ class TestDoclingServeChunker:
         mock_client_class.return_value.__aenter__.return_value = mock_client
 
         # Create a document with texts and tables that match the mocked refs
-        converter = get_converter(Config)
+        converter = get_converter(get_config())
         doc = await converter.convert_text(
             """# Chapter 1
 
@@ -700,7 +700,7 @@ async def test_local_and_serve_chunkers_produce_same_output(doclaynet_first_page
     from haiku.rag.converters.docling_serve import DoclingServeConverter
 
     # Use docling-serve to convert the PDF (ensures same conversion for both chunkers)
-    converter = DoclingServeConverter(Config)
+    converter = DoclingServeConverter(get_config())
     pdf_path = doclaynet_first_page_pdf
     doc = await converter.convert_file(pdf_path)
 
diff --git a/tests/test_client.py b/tests/test_client.py
index 2b29a146..75164823 100644
--- a/tests/test_client.py
+++ b/tests/test_client.py
@@ -17,7 +17,7 @@ from haiku.rag.client.documents import (
     _write_fetch_body,
     check_source_accessible,
 )
-from haiku.rag.config import Config
+from haiku.rag.config import get_config
 from haiku.rag.embeddings import EmbedderWrapper
 from haiku.rag.ingester.sources.base import FetchResult
 from haiku.rag.store.compression import decompress_json
@@ -813,7 +813,7 @@ async def test_client_import_document_with_custom_chunks(temp_db_path):
             Chunk(
                 content="This is the second chunk",
                 metadata={"custom": "metadata2"},
-                embedding=[0.1] * Config.embeddings.model.vector_dim,
+                embedding=[0.1] * get_config().embeddings.model.vector_dim,
                 order=1,
             ),  # With embedding
             Chunk(
@@ -856,7 +856,7 @@ def _docling_doc(name: str, text: str):
 
 def _import(name: str, text: str, **overrides) -> "DocumentImport":
     """Build a DocumentImport with one pre-embedded chunk (no embedder call)."""
-    dim = Config.embeddings.model.vector_dim
+    dim = get_config().embeddings.model.vector_dim
     chunk = Chunk(content=text, embedding=[0.1] * dim, order=0)
     return DocumentImport(
         docling_document=_docling_doc(name, text),
@@ -868,7 +868,7 @@ def _import(name: str, text: str, **overrides) -> "DocumentImport":
 async def test_client_import_documents_single_version_per_table(temp_db_path):
     """import_documents writes documents/chunks/document_items once for the
     whole batch (issue #287)."""
-    config = Config.model_copy(deep=True)
+    config = get_config().model_copy(deep=True)
     config.storage.auto_vacuum = False
 
     async with HaikuRAG(temp_db_path, config=config, create=True) as client:
@@ -902,7 +902,7 @@ async def test_client_import_documents_single_version_per_table(temp_db_path):
 
 async def test_client_import_documents_rolls_back_on_failure(temp_db_path):
     """A failure mid-batch restores all tables: nothing is persisted."""
-    dim = Config.embeddings.model.vector_dim
+    dim = get_config().embeddings.model.vector_dim
 
     async with HaikuRAG(temp_db_path, create=True) as client:
         good = _import("good", "Good document body", uri="mem://good")
@@ -943,7 +943,7 @@ async def test_client_import_documents_batches_embeddings(temp_db_path):
     """Chunks missing embeddings are embedded in one pass across the whole
     batch, not one embedder call per document. Duplicate chunk texts across
     documents keep their per-document embeddings."""
-    dim = Config.embeddings.model.vector_dim
+    dim = get_config().embeddings.model.vector_dim
     embedder = _CountingEmbedder(dim)
 
     async with HaikuRAG(temp_db_path, create=True) as client:
@@ -977,7 +977,7 @@ async def test_client_import_documents_batches_embeddings(temp_db_path):
 async def test_client_import_documents_mixed_embeddings(temp_db_path):
     """Pre-embedded chunks keep their vectors; only the unembedded ones go
     through the embedder, in one batch."""
-    dim = Config.embeddings.model.vector_dim
+    dim = get_config().embeddings.model.vector_dim
     embedder = _CountingEmbedder(dim)
 
     async with HaikuRAG(temp_db_path, create=True) as client:
@@ -1024,8 +1024,8 @@ async def test_client_update_document_replaces_rows_with_bounded_versions(
 
     auto_vacuum is off: its writes would land inside the measured window.
     """
-    dim = Config.embeddings.model.vector_dim
-    config = Config.model_copy(deep=True)
+    dim = get_config().embeddings.model.vector_dim
+    config = get_config().model_copy(deep=True)
     config.storage.auto_vacuum = False
 
     async with HaikuRAG(temp_db_path, config=config, create=True) as client:
@@ -1076,8 +1076,8 @@ async def test_metadata_only_update_does_not_advance_documents_table(temp_db_pat
     live in document_meta, so the documents table version must stay frozen while
     only metadata/title change — and reads must still hydrate the full Document.
     """
-    dim = Config.embeddings.model.vector_dim
-    config = Config.model_copy(deep=True)
+    dim = get_config().embeddings.model.vector_dim
+    config = get_config().model_copy(deep=True)
     config.storage.auto_vacuum = False
 
     async with HaikuRAG(temp_db_path, config=config, create=True) as client:
@@ -1121,7 +1121,7 @@ async def test_metadata_only_update_does_not_advance_documents_table(temp_db_pat
 async def test_delete_marks_vacuum_dirty(temp_db_path):
     """A delete adds tombstone/table versions, so it must enter the auto-vacuum
     lifecycle — otherwise a delete-only run closes without a final vacuum."""
-    dim = Config.embeddings.model.vector_dim
+    dim = get_config().embeddings.model.vector_dim
     async with HaikuRAG(temp_db_path, create=True) as client:
         doc = await client.import_document(
             _docling_doc("d", "body"),
@@ -1138,8 +1138,8 @@ async def test_delete_marks_vacuum_dirty(temp_db_path):
 async def test_delete_rolls_back_on_partial_failure(temp_db_path, monkeypatch):
     """A multi-table delete is atomic: if a later table delete fails, the write
     lock + version restore bring every table back, leaving no orphaned rows."""
-    dim = Config.embeddings.model.vector_dim
-    config = Config.model_copy(deep=True)
+    dim = get_config().embeddings.model.vector_dim
+    config = get_config().model_copy(deep=True)
     config.storage.auto_vacuum = False
 
     async with HaikuRAG(temp_db_path, config=config, create=True) as client:
@@ -1175,8 +1175,8 @@ async def test_cascade_delete_is_atomic(temp_db_path, monkeypatch):
     """Deleting a parent cascades to children under one lock + snapshot. If any
     delete in the subtree fails, the whole subtree is restored — a child isn't
     left deleted while its parent survives."""
-    dim = Config.embeddings.model.vector_dim
-    config = Config.model_copy(deep=True)
+    dim = get_config().embeddings.model.vector_dim
+    config = get_config().model_copy(deep=True)
     config.storage.auto_vacuum = False
 
     async with HaikuRAG(temp_db_path, config=config, create=True) as client:
@@ -2390,7 +2390,7 @@ async def test_metadata_only_update_waits_for_write_lock(temp_db_path):
     create_tag's version snapshot and its per-table tag creation)."""
     import asyncio
 
-    dim = Config.embeddings.model.vector_dim
+    dim = get_config().embeddings.model.vector_dim
     docling_doc = DoclingDocument(name="d")
     docling_doc.add_text(label=DocItemLabel.TEXT, text="body")
 
diff --git a/tests/test_config.py b/tests/test_config.py
index 19383411..fc431bc2 100644
--- a/tests/test_config.py
+++ b/tests/test_config.py
@@ -3,7 +3,7 @@ from pathlib import Path
 import pytest
 import yaml
 
-from haiku.rag.config import AppConfig
+from haiku.rag.config import AppConfig, set_config
 from haiku.rag.config.loader import (
     find_config_file,
     generate_default_config,
@@ -577,3 +577,48 @@ def test_example_configs_are_present():
 )
 def test_example_config_validates(path: Path):
     AppConfig.model_validate(yaml.safe_load(path.read_text()) or {})
+
+
+def _use_config(monkeypatch, cfg):
+    """Install cfg as the global config, restored by monkeypatch teardown."""
+    import haiku.rag.config as config_module
+
+    monkeypatch.setattr(config_module, "_config", None)
+    set_config(cfg)
+
+
+def test_set_config_reaches_the_factories(monkeypatch, tmp_path):
+    """A config installed after import must reach every factory and
+    constructor that resolves the global config itself."""
+    from haiku.rag.chunkers import get_chunker
+    from haiku.rag.chunkers.docling_serve import DoclingServeChunker
+    from haiku.rag.client import HaikuRAG
+    from haiku.rag.config.models import ModelConfig, RerankingConfig
+    from haiku.rag.converters import get_converter
+    from haiku.rag.converters.docling_serve import DoclingServeConverter
+    from haiku.rag.embeddings import get_embedder
+    from haiku.rag.reranking import get_reranker
+    from haiku.rag.reranking.vllm import VLLMReranker
+    from haiku.rag.store.engine import Store
+
+    cfg = AppConfig()
+    cfg.processing.converter = "docling-serve"
+    cfg.processing.chunker = "docling-serve"
+    cfg.embeddings.model.vector_dim = 7
+    cfg.reranking.model = ModelConfig(
+        provider="vllm", name="reranker-x", base_url="http://localhost:9/v1"
+    )
+    assert isinstance(cfg.reranking, RerankingConfig)
+
+    _use_config(monkeypatch, cfg)
+
+    assert isinstance(get_converter(), DoclingServeConverter)
+    assert isinstance(get_chunker(), DoclingServeChunker)
+    assert get_embedder().vector_dim == 7
+
+    reranker = get_reranker()
+    assert isinstance(reranker, VLLMReranker)
+    assert reranker._model == "reranker-x"
+
+    assert HaikuRAG(tmp_path / "db")._config is cfg
+    assert Store(tmp_path / "db", create=True)._config is cfg
diff --git a/tests/test_context_enhancement.py b/tests/test_context_enhancement.py
index 9fa11e72..2d68a481 100644
--- a/tests/test_context_enhancement.py
+++ b/tests/test_context_enhancement.py
@@ -69,7 +69,7 @@ def create_code_document() -> DoclingDocument:
     # Multiple adjacent code blocks - type-aware expansion should group them
     doc.add_text(label=DocItemLabel.CODE, text="# Part 1: Setup\nimport os\nimport sys")
     doc.add_text(
-        label=DocItemLabel.CODE, text='# Part 2: Config\nCONFIG = {"debug": True}'
+        label=DocItemLabel.CODE, text='# Part 2: get_config()\nCONFIG = {"debug": True}'
     )
     doc.add_text(
         label=DocItemLabel.CODE, text="# Part 3: Main\ndef main():\n    print(CONFIG)"
@@ -81,7 +81,7 @@ def create_code_document() -> DoclingDocument:
 
 @pytest.fixture
 def small_chunk_config() -> AppConfig:
-    """Config with small chunk size to force splitting."""
+    """get_config() with small chunk size to force splitting."""
     config = AppConfig()
     config.processing.chunk_size = 32
     config.search.max_context_chars = 10000
diff --git a/tests/test_download_models.py b/tests/test_download_models.py
index 41e571c5..1b01f8c3 100644
--- a/tests/test_download_models.py
+++ b/tests/test_download_models.py
@@ -5,7 +5,7 @@ import httpx
 import pytest
 
 from haiku.rag.client.downloads import download_models
-from haiku.rag.config import Config
+from haiku.rag.config import get_config
 from haiku.rag.config.models import ModelConfig
 
 
@@ -39,7 +39,7 @@ async def test_download_models_ollama_connect_error(mock_to_thread):
         with pytest.raises(
             ConnectionError, match="Cannot connect to Ollama"
         ) as exc_info:
-            async for _ in download_models(Config):
+            async for _ in download_models(get_config()):
                 pass
 
         assert "ollama serve" in str(exc_info.value)
@@ -74,7 +74,7 @@ async def test_download_models_ollama_pulls_models(mock_to_thread):
         return_value=_mock_httpx_client(mock_stream),
     ):
         events = []
-        async for progress in download_models(Config):
+        async for progress in download_models(get_config()):
             events.append(progress)
 
     # Default config has embeddings=qwen3-embedding:4b, qa=gpt-oss
diff --git a/tests/test_embedder.py b/tests/test_embedder.py
index bcb82da1..4c96b311 100644
--- a/tests/test_embedder.py
+++ b/tests/test_embedder.py
@@ -5,9 +5,9 @@ import pytest
 
 from haiku.rag.config import (
     AppConfig,
-    Config,
     EmbeddingModelConfig,
     EmbeddingsConfig,
+    get_config,
 )
 from haiku.rag.embeddings import (
     EmbedderWrapper,
@@ -197,7 +197,7 @@ async def test_embed_chunks_basic(allow_model_requests):
         ),
     ]
 
-    embedded_chunks = await embed_chunks(chunks, get_embedder(Config))
+    embedded_chunks = await embed_chunks(chunks, get_embedder(get_config()))
 
     assert len(embedded_chunks) == 2
     # Check that all original fields are preserved
@@ -216,7 +216,7 @@ async def test_embed_chunks_basic(allow_model_requests):
 async def test_embed_chunks_returns_new_objects(allow_model_requests):
     """Test that embed_chunks returns new Chunk objects (immutable pattern)."""
     original = Chunk(id="orig", content="Test content.")
-    embedded = await embed_chunks([original], get_embedder(Config))
+    embedded = await embed_chunks([original], get_embedder(get_config()))
 
     # Original should be unchanged
     assert original.embedding is None
@@ -302,7 +302,7 @@ async def test_embed_chunks_preserves_all_fields(allow_model_requests):
         document_meta={"author": "Test"},
     )
 
-    embedded = await embed_chunks([chunk], get_embedder(Config))
+    embedded = await embed_chunks([chunk], get_embedder(get_config()))
 
     assert embedded[0].id == "test-id"
     assert embedded[0].document_id == "doc-id"
diff --git a/tests/test_lancedb_connection.py b/tests/test_lancedb_connection.py
index ed65a5f9..2bdc5040 100644
--- a/tests/test_lancedb_connection.py
+++ b/tests/test_lancedb_connection.py
@@ -4,7 +4,7 @@ from unittest.mock import AsyncMock, patch
 import pytest
 from pydantic import ValidationError
 
-from haiku.rag.config import Config
+from haiku.rag.config import get_config
 from haiku.rag.config.models import AppConfig, LanceDBConfig
 from haiku.rag.store.engine import ConnectionMode, Store, connect_lancedb
 
@@ -139,16 +139,16 @@ class TestStoreConnectionMode:
     async def test_store_connection_mode_cloud(self, temp_db_path):
         async with Store(temp_db_path, create=True) as store:
             with (
-                patch.object(Config.lancedb, "uri", "db://test-database"),
-                patch.object(Config.lancedb, "api_key", "test-api-key"),
-                patch.object(Config.lancedb, "region", "us-east-1"),
+                patch.object(get_config().lancedb, "uri", "db://test-database"),
+                patch.object(get_config().lancedb, "api_key", "test-api-key"),
+                patch.object(get_config().lancedb, "region", "us-east-1"),
             ):
                 assert store._connection_mode == ConnectionMode.CLOUD
 
     @pytest.mark.asyncio
     async def test_store_connection_mode_object_storage(self, temp_db_path):
         async with Store(temp_db_path, create=True) as store:
-            with patch.object(Config.lancedb, "uri", "s3://bucket/path"):
+            with patch.object(get_config().lancedb, "uri", "s3://bucket/path"):
                 assert store._connection_mode == ConnectionMode.OBJECT_STORAGE
 
 
@@ -157,9 +157,9 @@ class TestVacuumByConnectionMode:
     async def test_cloud_skips_vacuum(self, temp_db_path):
         async with Store(temp_db_path, create=True) as store:
             with (
-                patch.object(Config.lancedb, "uri", "db://test-database"),
-                patch.object(Config.lancedb, "api_key", "test-api-key"),
-                patch.object(Config.lancedb, "region", "us-east-1"),
+                patch.object(get_config().lancedb, "uri", "db://test-database"),
+                patch.object(get_config().lancedb, "api_key", "test-api-key"),
+                patch.object(get_config().lancedb, "region", "us-east-1"),
             ):
                 with patch.object(
                     store.chunks_table, "optimize", new_callable=AsyncMock
@@ -170,7 +170,7 @@ class TestVacuumByConnectionMode:
     @pytest.mark.asyncio
     async def test_object_storage_runs_vacuum(self, temp_db_path):
         async with Store(temp_db_path, create=True) as store:
-            with patch.object(Config.lancedb, "uri", "s3://bucket/path"):
+            with patch.object(get_config().lancedb, "uri", "s3://bucket/path"):
                 with patch.object(
                     store.chunks_table, "optimize", new_callable=AsyncMock
                 ) as mock_optimize:
@@ -180,7 +180,7 @@ class TestVacuumByConnectionMode:
     @pytest.mark.asyncio
     async def test_local_runs_vacuum(self, temp_db_path):
         async with Store(temp_db_path, create=True) as store:
-            with patch.object(Config.lancedb, "uri", ""):
+            with patch.object(get_config().lancedb, "uri", ""):
                 with patch.object(
                     store.chunks_table, "optimize", new_callable=AsyncMock
                 ) as mock_optimize:
@@ -193,9 +193,9 @@ class TestVectorIndexByConnectionMode:
     async def test_cloud_skips_index_creation(self, temp_db_path):
         async with Store(temp_db_path, create=True) as store:
             with (
-                patch.object(Config.lancedb, "uri", "db://test-database"),
-                patch.object(Config.lancedb, "api_key", "test-api-key"),
-                patch.object(Config.lancedb, "region", "us-east-1"),
+                patch.object(get_config().lancedb, "uri", "db://test-database"),
+                patch.object(get_config().lancedb, "api_key", "test-api-key"),
+                patch.object(get_config().lancedb, "region", "us-east-1"),
             ):
                 with patch.object(
                     store.chunks_table, "count_rows", new_callable=AsyncMock
@@ -206,7 +206,7 @@ class TestVectorIndexByConnectionMode:
     @pytest.mark.asyncio
     async def test_object_storage_runs_index_creation(self, temp_db_path):
         async with Store(temp_db_path, create=True) as store:
-            with patch.object(Config.lancedb, "uri", "s3://bucket/path"):
+            with patch.object(get_config().lancedb, "uri", "s3://bucket/path"):
                 with patch.object(
                     store.chunks_table,
                     "count_rows",
diff --git a/tests/test_mcp.py b/tests/test_mcp.py
index 044c5779..860bf2a7 100644
--- a/tests/test_mcp.py
+++ b/tests/test_mcp.py
@@ -644,10 +644,10 @@ class TestMCPClientLifetime:
         """Validation is unchanged: same-dimension identity drift warns in
         read-only mode and raises in writable mode. The MCP server no longer
         opts out of it for deletion."""
-        from haiku.rag.config import Config
+        from haiku.rag.config import get_config
         from haiku.rag.store.repositories.settings import ConfigMismatchError
 
-        drifted = Config.model_copy(deep=True)
+        drifted = get_config().model_copy(deep=True)
         drifted.embeddings.model.name = "a-different-model"
 
         async with create_mcp_server(
diff --git a/tests/test_picture_in_context.py b/tests/test_picture_in_context.py
index c2c4c497..3ef84811 100644
--- a/tests/test_picture_in_context.py
+++ b/tests/test_picture_in_context.py
@@ -15,7 +15,7 @@ from pydantic_ai.usage import RunUsage
 from haiku.rag.capabilities.rag import RAGState, create_capability
 from haiku.rag.client import HaikuRAG
 from haiku.rag.client.search import _populate_image_data
-from haiku.rag.config import AppConfig, Config
+from haiku.rag.config import AppConfig, get_config
 from haiku.rag.store.models.chunk import Chunk, SearchResult
 from haiku.rag.store.models.document_item import DocumentItem
 from haiku.rag.tools.search import create_search_toolset
@@ -980,7 +980,7 @@ async def test_search_tool_returns_plain_string_when_no_pictures():
     fake_client.search = AsyncMock(return_value=[text_result])
     fake_client.expand_context = AsyncMock(return_value=[text_result])
 
-    toolset = create_search_toolset(Config, expand_context=False)
+    toolset = create_search_toolset(get_config(), expand_context=False)
     func = toolset.tools["search"].function
 
     ctx = RunContext(
diff --git a/tests/test_reader.py b/tests/test_reader.py
index 34d0637c..1f9b8f44 100644
--- a/tests/test_reader.py
+++ b/tests/test_reader.py
@@ -3,7 +3,7 @@ from pathlib import Path
 
 import pytest
 
-from haiku.rag.config import Config
+from haiku.rag.config import get_config
 from haiku.rag.converters import get_converter
 
 
@@ -19,7 +19,7 @@ async def test_code_file_wrapped_in_code_block():
         f.flush()
         temp_path = Path(f.name)
 
-        converter = get_converter(Config)
+        converter = get_converter(get_config())
         document = await converter.convert_file(temp_path)
         result = document.export_to_markdown()
 
diff --git a/tests/test_rebuild.py b/tests/test_rebuild.py
index 01c29a55..278065d0 100644
--- a/tests/test_rebuild.py
+++ b/tests/test_rebuild.py
@@ -6,7 +6,7 @@ from typing import TypedDict
 import pytest
 
 from haiku.rag.client import HaikuRAG, RebuildMode
-from haiku.rag.config import Config
+from haiku.rag.config import get_config
 from tests.conftest import capture_logs
 
 
@@ -194,7 +194,7 @@ async def test_rebuild_resumes_phase2_from_staging_after_crash(
     # crash, where no background vacuum would be in flight. Leaving it on lets
     # create_document's scheduled optimize race the raw drop_table ("Directory
     # not empty").
-    config = Config.model_copy(deep=True)
+    config = get_config().model_copy(deep=True)
     config.storage.auto_vacuum = False
 
     async with HaikuRAG(temp_db_path, config=config, create=True) as client:
@@ -1093,7 +1093,7 @@ async def test_rebuild_blocks_tag_operations(temp_db_path, monkeypatch):
 
     monkeypatch.setattr(EmbedderWrapper, "embed_documents", fake_embed_documents)
 
-    dim = Config.embeddings.model.vector_dim
+    dim = get_config().embeddings.model.vector_dim
     docling_doc = DoclingDocument(name="d")
     docling_doc.add_text(label=DocItemLabel.TEXT, text="body")
 
diff --git a/tests/test_reranker.py b/tests/test_reranker.py
index 1dea945f..eb4046eb 100644
--- a/tests/test_reranker.py
+++ b/tests/test_reranker.py
@@ -38,11 +38,9 @@ chunks = [
 
 @pytest.mark.asyncio
 async def test_reranker_base():
-    from haiku.rag.config import Config
-
     reranker = RerankerBase()
-    expected_model = Config.reranking.model.name if Config.reranking.model else None
-    assert reranker._model == expected_model
+    # The base carries no model: each reranker takes its own from the factory.
+    assert reranker._model is None
 
     # Empty input short-circuits in the base class without dispatching to _rerank.
     assert await reranker.rerank("query", []) == []
@@ -156,12 +154,12 @@ class TestGetReranker:
         [
             (
                 "cohere",
-                "rerank-v3.5",
+                "rerank-english-v3.0",
                 "haiku.rag.reranking.cohere",
                 "CohereReranker",
                 {},
-                {},
-                {},
+                {"_model": "rerank-english-v3.0"},
+                {"CO_API_KEY": "test-api-key"},
             ),
             (
                 "vllm",
diff --git a/tests/test_search.py b/tests/test_search.py
index 6a6e429f..26f883f2 100644
--- a/tests/test_search.py
+++ b/tests/test_search.py
@@ -1,14 +1,16 @@
 import pytest
 
 from haiku.rag.client import HaikuRAG
-from haiku.rag.config import Config
+from haiku.rag.config import get_config
 from haiku.rag.store.models import SearchResult
 
 
 @pytest.mark.vcr()
 async def test_search_qa_corpus(qa_corpus: list[dict[str, str]], temp_db_path):
     """Test that documents can be found by searching with their associated questions."""
-    async with HaikuRAG(db_path=temp_db_path, config=Config, create=True) as client:
+    async with HaikuRAG(
+        db_path=temp_db_path, config=get_config(), create=True
+    ) as client:
         # Load unique documents (limited to 10)
         seen_documents = set()
         documents = []
@@ -57,7 +59,9 @@ async def test_search_qa_corpus(qa_corpus: list[dict[str, str]], temp_db_path):
 @pytest.mark.vcr()
 async def test_search_chunk_includes_document_provenance(temp_db_path):
     """Test that raw chunk search results include document URI, metadata, and ID."""
-    async with HaikuRAG(db_path=temp_db_path, config=Config, create=True) as client:
+    async with HaikuRAG(
+        db_path=temp_db_path, config=get_config(), create=True
+    ) as client:
         # Create a document with URI and metadata but no title
         created_document = await client.create_document(
             content="This is a test document with some content for searching.",
@@ -92,7 +96,9 @@ async def test_search_chunk_includes_document_provenance(temp_db_path):
 @pytest.mark.vcr()
 async def test_search_score_types(temp_db_path):
     """Test that different search types return appropriate score ranges."""
-    async with HaikuRAG(db_path=temp_db_path, config=Config, create=True) as client:
+    async with HaikuRAG(
+        db_path=temp_db_path, config=get_config(), create=True
+    ) as client:
         # Create multiple documents with different content
         documents_content = [
             "Machine learning algorithms are powerful tools for data analysis and pattern recognition.",
@@ -159,7 +165,9 @@ async def test_search_score_types(temp_db_path):
 @pytest.mark.vcr()
 async def test_search_returns_search_result(temp_db_path):
     """Test that client.search() returns SearchResult with provenance info."""
-    async with HaikuRAG(db_path=temp_db_path, config=Config, create=True) as client:
+    async with HaikuRAG(
+        db_path=temp_db_path, config=get_config(), create=True
+    ) as client:
         await client.create_document(
             content="Machine learning models can classify images with high accuracy.",
             uri="https://example.com/ml.html",
@@ -188,7 +196,9 @@ async def test_search_graceful_degradation(temp_db_path):
     """Test search works when docling data is unavailable."""
     from haiku.rag.store.models import Chunk
 
-    async with HaikuRAG(db_path=temp_db_path, config=Config, create=True) as client:
+    async with HaikuRAG(
+        db_path=temp_db_path, config=get_config(), create=True
+    ) as client:
         # Import document with custom chunks (no docling document)
         custom_chunks = [
             Chunk(content="Custom chunk without docling metadata", metadata={}),
diff --git a/tests/test_settings.py b/tests/test_settings.py
index f30e2756..704b9eda 100644
--- a/tests/test_settings.py
+++ b/tests/test_settings.py
@@ -2,7 +2,7 @@ import logging
 
 import pytest
 
-from haiku.rag.config import AppConfig, Config
+from haiku.rag.config import AppConfig, get_config
 from haiku.rag.store.repositories.settings import ConfigMismatchError
 
 
@@ -16,7 +16,7 @@ async def test_settings_table_populated_on_store_init(temp_db_path):
         settings_repo = SettingsRepository(store)
 
         db_settings = await settings_repo.get_current_settings()
-        config_dict = Config.model_dump(mode="json")
+        config_dict = get_config().model_dump(mode="json")
 
         # Remove version from db_settings since it's added automatically
         db_settings_without_version = {
@@ -34,14 +34,14 @@ async def test_settings_save_and_retrieve(temp_db_path):
     async with Store(temp_db_path, create=True) as store:
         settings_repo = SettingsRepository(store)
 
-        original_chunk_size = Config.processing.chunk_size
-        Config.processing.chunk_size = 2 * original_chunk_size
+        original_chunk_size = get_config().processing.chunk_size
+        get_config().processing.chunk_size = 2 * original_chunk_size
 
         await settings_repo.save_current_settings()
         retrieved_settings = await settings_repo.get_current_settings()
         assert retrieved_settings["processing"]["chunk_size"] == 2 * original_chunk_size
 
-        Config.processing.chunk_size = original_chunk_size
+        get_config().processing.chunk_size = original_chunk_size
 
 
 @pytest.mark.asyncio
@@ -52,7 +52,7 @@ async def test_set_haiku_version_recreates_row_from_store_config(temp_db_path):
     from haiku.rag.store.repositories.settings import SettingsRepository
 
     config = AppConfig()
-    config.processing.chunk_size = Config.processing.chunk_size + 512
+    config.processing.chunk_size = get_config().processing.chunk_size + 512
 
     async with Store(temp_db_path, config=config, create=True) as store:
         settings_repo = SettingsRepository(store)
diff --git a/tests/test_utils.py b/tests/test_utils.py
index ad3c78b1..f8e71049 100644
--- a/tests/test_utils.py
+++ b/tests/test_utils.py
@@ -3,7 +3,7 @@ import importlib.util
 import pytest
 from pydantic_ai.models.openai import OpenAIChatModel
 
-from haiku.rag.config import Config
+from haiku.rag.config import get_config
 from haiku.rag.config.models import ModelConfig
 from haiku.rag.converters import get_converter
 from haiku.rag.utils import get_model
@@ -20,7 +20,7 @@ async def test_text_to_docling_document():
     """Test text to DoclingDocument conversion."""
     # Test basic text conversion
     simple_text = "This is a simple text document."
-    converter = get_converter(Config)
+    converter = get_converter(get_config())
     doc = await converter.convert_text(simple_text)
 
     # Verify it returns a DoclingDocument
@@ -44,7 +44,7 @@ def hello():
     return True
 ```"""
 
-    converter = get_converter(Config)
+    converter = get_converter(get_config())
     doc = await converter.convert_text(code_text, name="hello.md")
 
     # Verify it's a valid DoclingDocument
@@ -77,7 +77,7 @@ def test():
 
 **Bold text** and *italic text*."""
 
-    converter = get_converter(Config)
+    converter = get_converter(get_config())
     doc = await converter.convert_text(markdown_text, name="test.md")
 
     # Verify it's a DoclingDocument
@@ -95,7 +95,7 @@ def test():
 @pytest.mark.asyncio
 async def test_text_to_docling_document_empty_content():
     """Test text to DoclingDocument conversion with empty content."""
-    converter = get_converter(Config)
+    converter = get_converter(get_config())
     doc = await converter.convert_text("")
 
     # Should still create a valid DoclingDocument
@@ -124,7 +124,7 @@ function saludar() {
 
 Emoji test: 🚀 ✅ 📝"""
 
-    converter = get_converter(Config)
+    converter = get_converter(get_config())
     doc = await converter.convert_text(unicode_text, name="unicode.md")
 
     # Verify it's a DoclingDocument
diff --git a/tests/test_vacuum_debounce.py b/tests/test_vacuum_debounce.py
index 83a96dbc..6e6de526 100644
--- a/tests/test_vacuum_debounce.py
+++ b/tests/test_vacuum_debounce.py
@@ -5,7 +5,7 @@ import pytest
 import haiku.rag.client as client_mod
 from haiku.rag.client import HaikuRAG
 from haiku.rag.client.documents import _refresh_doc_metadata
-from haiku.rag.config import Config
+from haiku.rag.config import get_config
 from haiku.rag.store.models.chunk import Chunk
 
 
@@ -73,7 +73,7 @@ async def test_metadata_refresh_sweep_schedules_vacuum(temp_db_path):
     """A source re-sweep that only rolls source_revision (MD5/revision
     short-circuit) writes document_meta and must still schedule the (debounced)
     vacuum, so that tiny churn gets reclaimed instead of accumulating."""
-    dim = Config.embeddings.model.vector_dim
+    dim = get_config().embeddings.model.vector_dim
     async with HaikuRAG(temp_db_path, create=True) as client:
         doc = await client.import_document(
             _docling_doc("d", "body"),
@@ -99,7 +99,7 @@ async def test_metadata_refresh_waits_for_write_lock(temp_db_path):
     """The revision/MD5 short-circuit write serializes with other writers so
     it cannot land inside another writer's critical section (e.g. between
     create_tag's version snapshot and its per-table tag creation)."""
-    dim = Config.embeddings.model.vector_dim
+    dim = get_config().embeddings.model.vector_dim
     async with HaikuRAG(temp_db_path, create=True) as client:
         doc = await client.import_document(
             _docling_doc("d", "body"),
diff --git a/tests/test_versioning.py b/tests/test_versioning.py
index 2be4c855..9e8e7953 100644
--- a/tests/test_versioning.py
+++ b/tests/test_versioning.py
@@ -271,10 +271,10 @@ async def test_vacuum_with_retention_threshold(temp_db_path):
 @pytest.mark.vcr()
 async def test_vacuum_completes_before_context_exit(temp_db_path, monkeypatch):
     """Test that background vacuum completes when context manager exits."""
-    from haiku.rag.config import Config
+    from haiku.rag.config import get_config
 
     # Set aggressive vacuum retention for this test
-    monkeypatch.setattr(Config.storage, "vacuum_retention_seconds", 0)
+    monkeypatch.setattr(get_config().storage, "vacuum_retention_seconds", 0)
 
     async with HaikuRAG(db_path=temp_db_path, create=True) as client:
         # Create multiple documents - each creation triggers automatic vacuum with retention=0
@@ -302,9 +302,9 @@ async def test_aexit_awaits_background_vacuum(temp_db_path, monkeypatch):
     it yet when __aexit__ runs. Simply acquiring the vacuum lock (which is free until
     the task actually starts) would let close() proceed before vacuum runs.
     """
-    from haiku.rag.config import Config
+    from haiku.rag.config import get_config
 
-    monkeypatch.setattr(Config.storage, "auto_vacuum", True)
+    monkeypatch.setattr(get_config().storage, "auto_vacuum", True)
 
     vacuum_started = asyncio.Event()
     vacuum_completed = asyncio.Event()
@@ -339,9 +339,9 @@ async def test_aexit_awaits_all_background_vacuums(temp_db_path, monkeypatch):
     __aexit__ awaits the fast no-op B and closes the connection while Task A
     is still running.
     """
-    from haiku.rag.config import Config
+    from haiku.rag.config import get_config
 
-    monkeypatch.setattr(Config.storage, "auto_vacuum", True)
+    monkeypatch.setattr(get_config().storage, "auto_vacuum", True)
 
     first_vacuum_completed = asyncio.Event()
 
@@ -378,10 +378,10 @@ async def test_aexit_awaits_all_background_vacuums(temp_db_path, monkeypatch):
 @pytest.mark.vcr()
 async def test_auto_vacuum_disabled_skips_vacuum(temp_db_path, monkeypatch):
     """Test that auto_vacuum=False prevents automatic vacuum after operations."""
-    from haiku.rag.config import Config
+    from haiku.rag.config import get_config
 
     # Disable auto-vacuum
-    monkeypatch.setattr(Config.storage, "auto_vacuum", False)
+    monkeypatch.setattr(get_config().storage, "auto_vacuum", False)
 
     async with HaikuRAG(db_path=temp_db_path, create=True) as client:
         # Create multiple documents
@@ -404,11 +404,11 @@ async def test_auto_vacuum_disabled_skips_vacuum(temp_db_path, monkeypatch):
 @pytest.mark.vcr()
 async def test_auto_vacuum_enabled_triggers_vacuum(temp_db_path, monkeypatch):
     """Test that auto_vacuum=True (default) triggers vacuum after operations."""
-    from haiku.rag.config import Config
+    from haiku.rag.config import get_config
 
     # Enable auto-vacuum with aggressive retention
-    monkeypatch.setattr(Config.storage, "auto_vacuum", True)
-    monkeypatch.setattr(Config.storage, "vacuum_retention_seconds", 0)
+    monkeypatch.setattr(get_config().storage, "auto_vacuum", True)
+    monkeypatch.setattr(get_config().storage, "vacuum_retention_seconds", 0)
 
     async with HaikuRAG(db_path=temp_db_path, create=True) as client:
         # Create multiple documents
diff --git a/tests/tools/test_document.py b/tests/tools/test_document.py
index 967a1bf8..fc0ede4f 100644
--- a/tests/tools/test_document.py
+++ b/tests/tools/test_document.py
@@ -238,6 +238,6 @@ async def doc_client(temp_db_path):
 @pytest.fixture
 def doc_config():
     """Default AppConfig for document tests."""
-    from haiku.rag.config import Config
+    from haiku.rag.config import get_config
 
-    return Config
+    return get_config()
diff --git a/tests/tools/test_search.py b/tests/tools/test_search.py
index 8f09ad04..eb3efa99 100644
--- a/tests/tools/test_search.py
+++ b/tests/tools/test_search.py
@@ -205,9 +205,9 @@ async def search_client(temp_db_path):
 @pytest.fixture
 def search_config():
     """Default AppConfig for search tests."""
-    from haiku.rag.config import Config
+    from haiku.rag.config import get_config
 
-    return Config
+    return get_config()
 
 
 def _png_b64():