diff --git a/.github/workflows/cicd.yml b/.github/workflows/cicd.yml
index 9a50e28f..38172df8 100644
--- a/.github/workflows/cicd.yml
+++ b/.github/workflows/cicd.yml
@@ -70,11 +70,11 @@ jobs:
 
       - name: Install elasticsearch stac-fastapi
         run: |
-          pip install ./stac_fastapi/elasticsearch[dev,server]
+          pip install ./stac_api/elastic_search[dev,server]
 
       - name: Run test suite against Elasticsearch 7.x
         run: |
-          cd stac_fastapi/elasticsearch && pipenv run pytest -svvv
+          cd stac_api && pipenv run pytest -svvv
         env:
           ENVIRONMENT: testing
           ES_PORT: 9200
@@ -84,7 +84,7 @@ jobs:
 
       - name: Run test suite against Elasticsearch 8.x
         run: |
-          cd stac_fastapi/elasticsearch && pipenv run pytest -svvv
+          cd stac_api && pipenv run pytest -svvv
         env:
           ENVIRONMENT: testing
           ES_PORT: 9400
diff --git a/Dockerfile.dev b/Dockerfile.dev
deleted file mode 100644
index 4e2f0f4b..00000000
--- a/Dockerfile.dev
+++ /dev/null
@@ -1,18 +0,0 @@
-FROM python:3.10-slim
-
-
-# update apt pkgs, and install build-essential for ciso8601
-RUN apt-get update && \
-    apt-get -y upgrade && \
-    apt-get install -y build-essential && \
-    apt-get clean && \
-    rm -rf /var/lib/apt/lists/*
-
-# update certs used by Requests
-ENV CURL_CA_BUNDLE=/etc/ssl/certs/ca-certificates.crt
-
-WORKDIR /app
-
-COPY . /app
-
-RUN pip install --no-cache-dir -e ./stac_fastapi/elasticsearch[dev,server]
diff --git a/Dockerfile.dev.es b/Dockerfile.dev.es
new file mode 100644
index 00000000..f1194d1d
--- /dev/null
+++ b/Dockerfile.dev.es
@@ -0,0 +1,21 @@
+FROM python:3.10-slim
+
+# update apt pkgs, and install build-essential for ciso8601
+RUN apt-get update && \
+    apt-get -y upgrade && \
+    apt-get install -y build-essential && \
+    apt-get clean && \
+    rm -rf /var/lib/apt/lists/*
+
+# update certs used by Requests
+ENV CURL_CA BUNDLE=/etc/ssl/certs/ca-certificates.crt
+
+WORKDIR /app
+
+# Copy the contents of common and elastic_search directories directly into /app
+COPY ./stac_api/common /app/stac_api/common
+COPY ./stac_api/elastic_search /app/stac_api/elastic_search
+COPY ./stac_api/tests /app/stac_api/tests
+
+# Install dependencies
+RUN pip install --no-cache-dir -e ./stac_api/elastic_search[dev,server]
diff --git a/docker-compose.yml b/docker-compose.yml
index db3352fb..6cfe18ec 100644
--- a/docker-compose.yml
+++ b/docker-compose.yml
@@ -3,11 +3,11 @@ version: '3.9'
 services:
   app-elasticsearch:
     container_name: stac-fastapi-es
-    image: stac-utils/stac-fastapi
+    image: stac-utils/stac-fastapi-es
     restart: always
     build:
       context: .
-      dockerfile: Dockerfile.dev
+      dockerfile: Dockerfile.dev.es
     environment:
       - APP_HOST=0.0.0.0
       - APP_PORT=8080
@@ -18,16 +18,48 @@ services:
       - ES_PORT=9200
       - ES_USE_SSL=false
       - ES_VERIFY_CERTS=false
+      - DB_TYPE=elasticsearch
     ports:
       - "8080:8080"
     volumes:
-      - ./stac_fastapi:/app/stac_fastapi
+      - ./stac_api/elastic_search:/app/stac_api/elastic_search
+      - ./stac_api/common:/app/stac_api/common
+      - ./stac_api/tests:/app/stac_api/tests
       - ./scripts:/app/scripts
       - ./esdata:/usr/share/elasticsearch/data
     depends_on:
       - elasticsearch
     command:
-      bash -c "./scripts/wait-for-it-es.sh es-container:9200 && python -m stac_fastapi.elasticsearch.app"
+      bash -c "./scripts/wait-for-it-es.sh es-container:9200 && python -m stac_api.elastic_search.app"
+
+  app-opensearch:
+    container_name: stac-fastapi-os
+    image: stac-utils/stac-fastapi-os
+    restart: always
+    build:
+      context: .
+      dockerfile: Dockerfile.dev
+    environment:
+      - APP_HOST=0.0.0.0
+      - APP_PORT=8080
+      - RELOAD=true
+      - ENVIRONMENT=local
+      - WEB_CONCURRENCY=10
+      - ES_HOST=172.17.0.1
+      - ES_PORT=9200
+      - ES_USE_SSL=false
+      - ES_VERIFY_CERTS=false
+      - DB_TYPE=opensearch
+    ports:
+      - "8082:8080"
+    volumes:
+      - ./stac_fastapi:/app/stac_fastapi
+      - ./scripts:/app/scripts
+      - ./osdata:/usr/share/opensearch/data
+    depends_on:
+      - opensearch
+    command:
+      bash -c "./scripts/wait-for-it-es.sh os-container:9200 && python -m stac_fastapi.elastic_search.app"
 
   elasticsearch:
     container_name: es-container
@@ -39,3 +71,15 @@ services:
       - ./elasticsearch/snapshots:/usr/share/elasticsearch/snapshots
     ports:
       - "9200:9200"
+
+  opensearch:
+    container_name: os-container
+    image: opensearchproject/opensearch:latest
+    environment:
+      - "discovery.type=single-node"
+      - "plugins.security.disabled=true"
+    volumes:
+      - ./opensearch/config/opensearch.yml:/usr/share/opensearch/config/opensearch.yml
+      - ./opensearch/snapshots:/usr/share/opensearch/snapshots
+    ports:
+      - "9202:9200"
diff --git a/examples/pip_docker/docker-compose.yml b/examples/pip_docker/docker-compose.yml
index 2c2d289e..8c76967d 100644
--- a/examples/pip_docker/docker-compose.yml
+++ b/examples/pip_docker/docker-compose.yml
@@ -27,7 +27,7 @@ services:
     depends_on:
       - elasticsearch
     command:
-      bash -c "./scripts/wait-for-it-es.sh es-container:9200 && python -m stac_fastapi.elasticsearch.app"
+      bash -c "./scripts/wait-for-it-es.sh es-container:9200 && python -m stac_fastapi.elastic_search.app"
 
   elasticsearch:
     container_name: es-container
diff --git a/opensearch/config/opensearch.yml b/opensearch/config/opensearch.yml
new file mode 100644
index 00000000..dc69776a
--- /dev/null
+++ b/opensearch/config/opensearch.yml
@@ -0,0 +1,35 @@
+## Cluster Settings
+cluster.name: stac-cluster
+node.name: es01
+network.host: 0.0.0.0
+transport.host: 0.0.0.0
+discovery.type: single-node
+http.port: 9200
+
+path:
+  repo:
+    - /usr/share/opensearch/snapshots
+
+######## Start OpenSearch Security Demo Configuration ########
+# WARNING: revise all the lines below before you go into production
+plugins.security.ssl.transport.pemcert_filepath: esnode.pem
+plugins.security.ssl.transport.pemkey_filepath: esnode-key.pem
+plugins.security.ssl.transport.pemtrustedcas_filepath: root-ca.pem
+plugins.security.ssl.transport.enforce_hostname_verification: false
+plugins.security.ssl.http.enabled: true
+plugins.security.ssl.http.pemcert_filepath: esnode.pem
+plugins.security.ssl.http.pemkey_filepath: esnode-key.pem
+plugins.security.ssl.http.pemtrustedcas_filepath: root-ca.pem
+plugins.security.allow_unsafe_democertificates: true
+plugins.security.allow_default_init_securityindex: true
+plugins.security.authcz.admin_dn:
+  - CN=kirk,OU=client,O=client,L=test, C=de
+
+plugins.security.audit.type: internal_opensearch
+plugins.security.enable_snapshot_restore_privilege: true
+plugins.security.check_snapshot_restore_write_privileges: true
+plugins.security.restapi.roles_enabled: ["all_access", "security_rest_api_access"]
+plugins.security.system_indices.enabled: true
+plugins.security.system_indices.indices: [".plugins-ml-config", ".plugins-ml-connector", ".plugins-ml-model-group", ".plugins-ml-model", ".plugins-ml-task", ".plugins-ml-conversation-meta", ".plugins-ml-conversation-interactions", ".opendistro-alerting-config", ".opendistro-alerting-alert*", ".opendistro-anomaly-results*", ".opendistro-anomaly-detector*", ".opendistro-anomaly-checkpoints", ".opendistro-anomaly-detection-state", ".opendistro-reports-*", ".opensearch-notifications-*", ".opensearch-notebooks", ".opensearch-observability", ".ql-datasources", ".opendistro-asynchronous-search-response*", ".replication-metadata-store", ".opensearch-knn-models", ".geospatial-ip2geo-data*"]
+node.max_local_storage_nodes: 3
+######## End OpenSearch Security Demo Configuration ########
diff --git a/stac_api/__init__.py b/stac_api/__init__.py
new file mode 100644
index 00000000..11a01537
--- /dev/null
+++ b/stac_api/__init__.py
@@ -0,0 +1 @@
+"""stac api."""
diff --git a/stac_api/common/__init__.py b/stac_api/common/__init__.py
new file mode 100644
index 00000000..69f055ab
--- /dev/null
+++ b/stac_api/common/__init__.py
@@ -0,0 +1 @@
+"""elasticsearch/ opensearch shared code."""
diff --git a/stac_api/common/base_database_logic.py b/stac_api/common/base_database_logic.py
new file mode 100644
index 00000000..09bb01a6
--- /dev/null
+++ b/stac_api/common/base_database_logic.py
@@ -0,0 +1,47 @@
+"""base class for database logic."""
+
+# from abc import ABC, abstractmethod
+# from typing import Any, Dict, List, Optional, Tuple, Union
+
+# from stac_fastapi.types.stac import Collection, Item
+
+
+# class BaseDatabaseLogic(ABC):
+#     """
+#     Abstract base class for database logic.
+#     This class defines the interface for database operations.
+#     """
+
+#     @abstractmethod
+#     async def get_all_collections(self, token: Optional[str], limit: int) -> Any:
+#         pass
+
+#     @abstractmethod
+#     async def get_one_item(self, collection_id: str, item_id: str) -> Dict:
+#         pass
+
+#     @abstractmethod
+#     async def create_item(self, item: Item, refresh: bool = False) -> None:
+#         pass
+
+#     @abstractmethod
+#     async def delete_item(
+#         self, item_id: str, collection_id: str, refresh: bool = False
+#     ) -> None:
+#         pass
+
+#     @abstractmethod
+#     async def create_collection(
+#         self, collection: Collection, refresh: bool = False
+#     ) -> None:
+#         pass
+
+#     @abstractmethod
+#     async def find_collection(self, collection_id: str) -> Collection:
+#         pass
+
+#     @abstractmethod
+#     async def delete_collection(
+#         self, collection_id: str, refresh: bool = False
+#     ) -> None:
+#         pass
diff --git a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/core.py b/stac_api/common/core.py
similarity index 89%
rename from stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/core.py
rename to stac_api/common/core.py
index 12cc6b2c..918b5ce0 100644
--- a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/core.py
+++ b/stac_api/common/core.py
@@ -1,4 +1,5 @@
 """Item crud client."""
+import importlib
 import logging
 import re
 from base64 import urlsafe_b64encode
@@ -18,12 +19,11 @@
 from stac_pydantic.links import Relations
 from stac_pydantic.shared import MimeTypes
 
-from stac_fastapi.elasticsearch import serializers
-from stac_fastapi.elasticsearch.config import ElasticsearchSettings
-from stac_fastapi.elasticsearch.database_logic import DatabaseLogic
-from stac_fastapi.elasticsearch.models.links import PagingLinks
-from stac_fastapi.elasticsearch.serializers import CollectionSerializer, ItemSerializer
-from stac_fastapi.elasticsearch.session import Session
+# from common.base_database_logic import BaseDatabaseLogic
+from stac_api.common.models.links import PagingLinks
+from stac_api.elastic_search import serializers
+from stac_api.elastic_search.serializers import CollectionSerializer, ItemSerializer
+from stac_api.elastic_search.session import Session
 from stac_fastapi.extensions.third_party.bulk_transactions import (
     BaseBulkTransactionsClient,
     BulkTransactionMethod,
@@ -66,12 +66,36 @@ class CoreClient(AsyncBaseCoreClient):
 
     session: Session = attr.ib(default=attr.Factory(Session.create_from_env))
     item_serializer: Type[serializers.ItemSerializer] = attr.ib(
-        default=serializers.ItemSerializer
+        default=serializers.ItemSerializer  # type: ignore
     )
     collection_serializer: Type[serializers.CollectionSerializer] = attr.ib(
-        default=serializers.CollectionSerializer
+        default=serializers.CollectionSerializer  # type: ignore
     )
-    database = DatabaseLogic()
+    post_request_model = attr.ib(default=BaseSearchPostRequest)
+
+    def __attrs_post_init__(self):
+        """
+        Post-initialization method for CoreClient.
+
+        This method is automatically called after CoreClient's instance is initialized.
+        It's responsible for setting up the database logic dynamically based on the
+        environment or configuration, ensuring that the appropriate database logic
+        (Elasticsearch or OpenSearch) is used.
+        """
+        try:
+            # Dynamically import the database logic based on installed package
+            database_module = importlib.import_module(
+                "stac_api.elastic_search.database_logic"
+            )
+            DatabaseLogicClass = getattr(database_module, "DatabaseLogic")
+        except ImportError:
+            # Fall back to OpenSearch if Elasticsearch is not available
+            database_module = importlib.import_module(
+                "stac_api.open_search.database_logic"
+            )
+            DatabaseLogicClass = getattr(database_module, "DatabaseLogic")
+
+        self.database = DatabaseLogicClass()
 
     @overrides
     async def all_collections(self, **kwargs) -> Collections:
@@ -542,7 +566,31 @@ class TransactionsClient(AsyncBaseTransactionsClient):
     """Transactions extension specific CRUD operations."""
 
     session: Session = attr.ib(default=attr.Factory(Session.create_from_env))
-    database = DatabaseLogic()
+    # database: BaseDatabaseLogic = attr.ib(init=False)
+
+    def __attrs_post_init__(self):
+        """
+        Post-initialization method for TransactionsClient.
+
+        This method is automatically called after the instance is initialized.
+        It's responsible for setting up the database logic dynamically based on the
+        environment or configuration, ensuring that the appropriate database logic
+        (Elasticsearch or OpenSearch) is used.
+        """
+        try:
+            # Dynamically import the database logic based on installed package
+            database_module = importlib.import_module(
+                "stac_api.elastic_search.database_logic"
+            )
+            DatabaseLogicClass = getattr(database_module, "DatabaseLogic")
+        except ImportError:
+            # Fall back to OpenSearch if Elasticsearch is not available
+            database_module = importlib.import_module(
+                "stac_api.opensearch.database_logic"
+            )
+            DatabaseLogicClass = getattr(database_module, "DatabaseLogic")
+
+        self.database = DatabaseLogicClass()
 
     @overrides
     async def create_item(
@@ -712,12 +760,31 @@ class BulkTransactionsClient(BaseBulkTransactionsClient):
     """
 
     session: Session = attr.ib(default=attr.Factory(Session.create_from_env))
-    database = DatabaseLogic()
+    # database: BaseDatabaseLogic = attr.ib(init=False)
 
     def __attrs_post_init__(self):
-        """Create es engine."""
-        settings = ElasticsearchSettings()
-        self.client = settings.create_client
+        """
+        Post-initialization method for BulkTransactionsClient.
+
+        This method is automatically called after the instance is initialized.
+        It's responsible for setting up the database logic dynamically based on the
+        environment or configuration, ensuring that the appropriate database logic
+        (Elasticsearch or OpenSearch) is used.
+        """
+        try:
+            # Dynamically import the database logic based on installed package
+            database_module = importlib.import_module(
+                "stac_api.elastic_search.database_logic"
+            )
+            DatabaseLogicClass = getattr(database_module, "DatabaseLogic")
+        except ImportError:
+            # Fall back to OpenSearch if Elasticsearch is not available
+            database_module = importlib.import_module(
+                "stac_api.opensearch.database_logic"
+            )
+            DatabaseLogicClass = getattr(database_module, "DatabaseLogic")
+
+        self.database = DatabaseLogicClass()
 
     def preprocess_item(
         self, item: stac_types.Item, base_url, method: BulkTransactionMethod
diff --git a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/datetime_utils.py b/stac_api/common/datetime_utils.py
similarity index 100%
rename from stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/datetime_utils.py
rename to stac_api/common/datetime_utils.py
diff --git a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/extensions/__init__.py b/stac_api/common/extensions/__init__.py
similarity index 100%
rename from stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/extensions/__init__.py
rename to stac_api/common/extensions/__init__.py
diff --git a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/extensions/filter.py b/stac_api/common/extensions/filter.py
similarity index 100%
rename from stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/extensions/filter.py
rename to stac_api/common/extensions/filter.py
diff --git a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/extensions/query.py b/stac_api/common/extensions/query.py
similarity index 100%
rename from stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/extensions/query.py
rename to stac_api/common/extensions/query.py
diff --git a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/models/__init__.py b/stac_api/common/models/__init__.py
similarity index 100%
rename from stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/models/__init__.py
rename to stac_api/common/models/__init__.py
diff --git a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/models/links.py b/stac_api/common/models/links.py
similarity index 100%
rename from stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/models/links.py
rename to stac_api/common/models/links.py
diff --git a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/models/search.py b/stac_api/common/models/search.py
similarity index 100%
rename from stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/models/search.py
rename to stac_api/common/models/search.py
diff --git a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/types/search.py b/stac_api/common/types/search.py
similarity index 97%
rename from stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/types/search.py
rename to stac_api/common/types/search.py
index 26a2dbb6..b2536021 100644
--- a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/types/search.py
+++ b/stac_api/common/types/search.py
@@ -8,7 +8,7 @@
 
 from stac_pydantic.api.extensions.fields import FieldsExtension as FieldsBase
 
-from stac_fastapi.types.config import Settings
+from stac_api.types.config import Settings
 
 logger = logging.getLogger("uvicorn")
 logger.setLevel(logging.INFO)
diff --git a/stac_fastapi/elasticsearch/README.md b/stac_api/elastic_search/README.md
similarity index 100%
rename from stac_fastapi/elasticsearch/README.md
rename to stac_api/elastic_search/README.md
diff --git a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/__init__.py b/stac_api/elastic_search/__init__.py
similarity index 100%
rename from stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/__init__.py
rename to stac_api/elastic_search/__init__.py
diff --git a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/app.py b/stac_api/elastic_search/app.py
similarity index 85%
rename from stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/app.py
rename to stac_api/elastic_search/app.py
index 8adcece4..b0fbc709 100644
--- a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/app.py
+++ b/stac_api/elastic_search/app.py
@@ -1,16 +1,18 @@
 """FastAPI application."""
-from stac_fastapi.api.app import StacApi
-from stac_fastapi.api.models import create_get_request_model, create_post_request_model
-from stac_fastapi.elasticsearch.config import ElasticsearchSettings
-from stac_fastapi.elasticsearch.core import (
+import sys
+
+from stac_api.common.core import (
     BulkTransactionsClient,
     CoreClient,
     EsAsyncBaseFiltersClient,
     TransactionsClient,
 )
-from stac_fastapi.elasticsearch.database_logic import create_collection_index
-from stac_fastapi.elasticsearch.extensions import QueryExtension
-from stac_fastapi.elasticsearch.session import Session
+from stac_api.common.extensions import QueryExtension
+from stac_api.elastic_search.config import ElasticsearchSettings
+from stac_api.elastic_search.database_logic import create_collection_index
+from stac_api.elastic_search.session import Session
+from stac_fastapi.api.app import StacApi
+from stac_fastapi.api.models import create_get_request_model, create_post_request_model
 from stac_fastapi.extensions.core import (
     ContextExtension,
     FieldsExtension,
@@ -21,6 +23,8 @@
 )
 from stac_fastapi.extensions.third_party import BulkTransactionExtension
 
+print("API sys.path:", sys.path)
+
 settings = ElasticsearchSettings()
 session = Session.create_from_settings(settings)
 
@@ -63,7 +67,7 @@ def run() -> None:
         import uvicorn
 
         uvicorn.run(
-            "stac_fastapi.elasticsearch.app:app",
+            "stac_api.elastic_search.app:app",
             host=settings.app_host,
             port=settings.app_port,
             log_level="info",
diff --git a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/config.py b/stac_api/elastic_search/config.py
similarity index 100%
rename from stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/config.py
rename to stac_api/elastic_search/config.py
diff --git a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/database_logic.py b/stac_api/elastic_search/database_logic.py
similarity index 96%
rename from stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/database_logic.py
rename to stac_api/elastic_search/database_logic.py
index 336c8d07..3693158c 100644
--- a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/database_logic.py
+++ b/stac_api/elastic_search/database_logic.py
@@ -9,12 +9,13 @@
 from elasticsearch_dsl import Q, Search
 
 from elasticsearch import exceptions, helpers  # type: ignore
-from stac_fastapi.elasticsearch import serializers
-from stac_fastapi.elasticsearch.config import AsyncElasticsearchSettings
-from stac_fastapi.elasticsearch.config import (
+from stac_api.common.extensions import filter
+from stac_api.elastic_search import serializers
+from stac_api.elastic_search.config import AsyncElasticsearchSettings
+from stac_api.elastic_search.config import (
     ElasticsearchSettings as SyncElasticsearchSettings,
 )
-from stac_fastapi.elasticsearch.extensions import filter
+from stac_api.elastic_search.utilities import bbox2polygon
 from stac_fastapi.types.errors import ConflictError, NotFoundError
 from stac_fastapi.types.stac import Collection, Item
 
@@ -229,21 +230,6 @@ async def delete_item_index(collection_id: str):
     await client.close()
 
 
-def bbox2polygon(b0: float, b1: float, b2: float, b3: float) -> List[List[List[float]]]:
-    """Transform a bounding box represented by its four coordinates `b0`, `b1`, `b2`, and `b3` into a polygon.
-
-    Args:
-        b0 (float): The x-coordinate of the lower-left corner of the bounding box.
-        b1 (float): The y-coordinate of the lower-left corner of the bounding box.
-        b2 (float): The x-coordinate of the upper-right corner of the bounding box.
-        b3 (float): The y-coordinate of the upper-right corner of the bounding box.
-
-    Returns:
-        List[List[List[float]]]: A polygon represented as a list of lists of coordinates.
-    """
-    return [[[b0, b1], [b2, b1], [b2, b3], [b0, b3], [b0, b1]]]
-
-
 def mk_item_id(item_id: str, collection_id: str):
     """Create the document id for an Item in Elasticsearch.
 
@@ -297,10 +283,10 @@ class DatabaseLogic:
     sync_client = SyncElasticsearchSettings().create_client
 
     item_serializer: Type[serializers.ItemSerializer] = attr.ib(
-        default=serializers.ItemSerializer
+        default=serializers.ItemSerializer  # type: ignore
     )
     collection_serializer: Type[serializers.CollectionSerializer] = attr.ib(
-        default=serializers.CollectionSerializer
+        default=serializers.CollectionSerializer  # type: ignore
     )
 
     """CORE LOGIC"""
diff --git a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/serializers.py b/stac_api/elastic_search/serializers.py
similarity index 98%
rename from stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/serializers.py
rename to stac_api/elastic_search/serializers.py
index 725e8f65..58b9f458 100644
--- a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/serializers.py
+++ b/stac_api/elastic_search/serializers.py
@@ -4,7 +4,7 @@
 
 import attr
 
-from stac_fastapi.elasticsearch.datetime_utils import now_to_rfc3339_str
+from stac_api.common.datetime_utils import now_to_rfc3339_str
 from stac_fastapi.types import stac as stac_types
 from stac_fastapi.types.links import CollectionLinks, ItemLinks, resolve_links
 
diff --git a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/session.py b/stac_api/elastic_search/session.py
similarity index 100%
rename from stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/session.py
rename to stac_api/elastic_search/session.py
diff --git a/stac_api/elastic_search/setup.cfg b/stac_api/elastic_search/setup.cfg
new file mode 100644
index 00000000..f1023827
--- /dev/null
+++ b/stac_api/elastic_search/setup.cfg
@@ -0,0 +1,2 @@
+[metadata]
+version = attr: version.__version__
diff --git a/stac_fastapi/elasticsearch/setup.py b/stac_api/elastic_search/setup.py
similarity index 88%
rename from stac_fastapi/elasticsearch/setup.py
rename to stac_api/elastic_search/setup.py
index 3106c512..d8420886 100644
--- a/stac_fastapi/elasticsearch/setup.py
+++ b/stac_api/elastic_search/setup.py
@@ -8,13 +8,13 @@
 install_requires = [
     "fastapi",
     "attrs",
+    "elasticsearch[async]==8.11.0",
+    "elasticsearch-dsl==8.11.0",
     "pydantic[dotenv]<2",
     "stac_pydantic==2.0.*",
     "stac-fastapi.types==2.4.9",
     "stac-fastapi.api==2.4.9",
     "stac-fastapi.extensions==2.4.9",
-    "elasticsearch[async]==8.11.0",
-    "elasticsearch-dsl==8.11.0",
     "pystac[validation]",
     "uvicorn",
     "orjson",
@@ -56,14 +56,17 @@
     ],
     url="https://github.com/stac-utils/stac-fastapi-elasticsearch",
     license="MIT",
-    packages=find_namespace_packages(exclude=["alembic", "tests", "scripts"]),
+    packages=find_namespace_packages(
+        include=["elastic_search", "elastic_search.*", "common", "common.*"],
+        exclude=["tests", "scripts"],
+    ),
     zip_safe=False,
     install_requires=install_requires,
     tests_require=extra_reqs["dev"],
     extras_require=extra_reqs,
     entry_points={
         "console_scripts": [
-            "stac-fastapi-elasticsearch=stac_fastapi.elasticsearch.app:run"
+            "stac-fastapi-elasticsearch=stac_api.elastic_search.app:run"
         ]
     },
 )
diff --git a/stac_api/elastic_search/utilities.py b/stac_api/elastic_search/utilities.py
new file mode 100644
index 00000000..4646cfe0
--- /dev/null
+++ b/stac_api/elastic_search/utilities.py
@@ -0,0 +1,22 @@
+"""Module for geospatial processing functions.
+
+This module contains functions for transforming geospatial coordinates,
+such as converting bounding boxes to polygon representations.
+"""
+
+from typing import List
+
+
+def bbox2polygon(b0: float, b1: float, b2: float, b3: float) -> List[List[List[float]]]:
+    """Transform a bounding box represented by its four coordinates `b0`, `b1`, `b2`, and `b3` into a polygon.
+
+    Args:
+        b0 (float): The x-coordinate of the lower-left corner of the bounding box.
+        b1 (float): The y-coordinate of the lower-left corner of the bounding box.
+        b2 (float): The x-coordinate of the upper-right corner of the bounding box.
+        b3 (float): The y-coordinate of the upper-right corner of the bounding box.
+
+    Returns:
+        List[List[List[float]]]: A polygon represented as a list of lists of coordinates.
+    """
+    return [[[b0, b1], [b2, b1], [b2, b3], [b0, b3], [b0, b1]]]
diff --git a/stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/version.py b/stac_api/elastic_search/version.py
similarity index 100%
rename from stac_fastapi/elasticsearch/stac_fastapi/elasticsearch/version.py
rename to stac_api/elastic_search/version.py
diff --git a/stac_api/open_search/setup.cfg b/stac_api/open_search/setup.cfg
new file mode 100644
index 00000000..f1023827
--- /dev/null
+++ b/stac_api/open_search/setup.cfg
@@ -0,0 +1,2 @@
+[metadata]
+version = attr: version.__version__
diff --git a/stac_api/open_search/setup.py b/stac_api/open_search/setup.py
new file mode 100644
index 00000000..2c0607fc
--- /dev/null
+++ b/stac_api/open_search/setup.py
@@ -0,0 +1,68 @@
+"""stac_fastapi: elasticsearch module."""
+
+from setuptools import find_namespace_packages, setup
+
+with open("README.md") as f:
+    desc = f.read()
+
+install_requires = [
+    "fastapi",
+    "attrs",
+    "elasticsearch[async]==8.11.0",
+    "elasticsearch-dsl==8.11.0",
+    "pydantic[dotenv]<2",
+    "stac_pydantic==2.0.*",
+    "stac-fastapi.types==2.4.9",
+    "stac-fastapi.api==2.4.9",
+    "stac-fastapi.extensions==2.4.9",
+    "pystac[validation]",
+    "uvicorn",
+    "orjson",
+    "overrides",
+    "starlette",
+    "geojson-pydantic",
+    "pygeofilter==0.2.1",
+]
+
+extra_reqs = {
+    "dev": [
+        "pytest",
+        "pytest-cov",
+        "pytest-asyncio",
+        "pre-commit",
+        "requests",
+        "ciso8601",
+        "httpx",
+    ],
+    "docs": ["mkdocs", "mkdocs-material", "pdocs"],
+    "server": ["uvicorn[standard]==0.19.0"],
+}
+
+setup(
+    name="stac-fastapi.elasticsearch",
+    description="An implementation of STAC API based on the FastAPI framework with Elasticsearch.",
+    long_description=desc,
+    long_description_content_type="text/markdown",
+    python_requires=">=3.8",
+    classifiers=[
+        "Intended Audience :: Developers",
+        "Intended Audience :: Information Technology",
+        "Intended Audience :: Science/Research",
+        "Programming Language :: Python :: 3.8",
+        "Programming Language :: Python :: 3.9",
+        "Programming Language :: Python :: 3.10",
+        "Programming Language :: Python :: 3.11",
+        "License :: OSI Approved :: MIT License",
+    ],
+    url="https://github.com/stac-utils/stac-fastapi-elasticsearch",
+    license="MIT",
+    packages=find_namespace_packages(
+        include=["elasticsearch", "elasticsearch.*", "common", "common.*"],
+        exclude=["tests", "scripts"],
+    ),
+    zip_safe=False,
+    install_requires=install_requires,
+    tests_require=extra_reqs["dev"],
+    extras_require=extra_reqs,
+    entry_points={"console_scripts": ["stac-fastapi-elasticsearch=app:run"]},
+)
diff --git a/stac_api/open_search/version.py b/stac_api/open_search/version.py
new file mode 100644
index 00000000..1eeef171
--- /dev/null
+++ b/stac_api/open_search/version.py
@@ -0,0 +1,2 @@
+"""library version."""
+__version__ = "1.0.0"
diff --git a/stac_fastapi/elasticsearch/pytest.ini b/stac_api/pytest.ini
similarity index 56%
rename from stac_fastapi/elasticsearch/pytest.ini
rename to stac_api/pytest.ini
index db0353ef..f770b9c9 100644
--- a/stac_fastapi/elasticsearch/pytest.ini
+++ b/stac_api/pytest.ini
@@ -1,4 +1,4 @@
 [pytest]
-testpaths = tests
+testpaths = elastic_search/tests
 addopts = -sv
 asyncio_mode = auto
\ No newline at end of file
diff --git a/stac_fastapi/elasticsearch/tests/__init__.py b/stac_api/tests/__init__.py
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/__init__.py
rename to stac_api/tests/__init__.py
diff --git a/stac_fastapi/elasticsearch/tests/api/__init__.py b/stac_api/tests/api/__init__.py
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/api/__init__.py
rename to stac_api/tests/api/__init__.py
diff --git a/stac_fastapi/elasticsearch/tests/api/test_api.py b/stac_api/tests/api/test_api.py
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/api/test_api.py
rename to stac_api/tests/api/test_api.py
diff --git a/stac_fastapi/elasticsearch/tests/clients/__init__.py b/stac_api/tests/clients/__init__.py
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/clients/__init__.py
rename to stac_api/tests/clients/__init__.py
diff --git a/stac_fastapi/elasticsearch/tests/clients/test_elasticsearch.py b/stac_api/tests/clients/test_elasticsearch.py
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/clients/test_elasticsearch.py
rename to stac_api/tests/clients/test_elasticsearch.py
diff --git a/stac_fastapi/elasticsearch/tests/conftest.py b/stac_api/tests/conftest.py
similarity index 90%
rename from stac_fastapi/elasticsearch/tests/conftest.py
rename to stac_api/tests/conftest.py
index fa093af2..157cabce 100644
--- a/stac_fastapi/elasticsearch/tests/conftest.py
+++ b/stac_api/tests/conftest.py
@@ -1,3 +1,7 @@
+# import sys
+
+# sys.path.insert(0, "/app")
+
 import asyncio
 import copy
 import json
@@ -8,16 +12,12 @@
 import pytest_asyncio
 from httpx import AsyncClient
 
+from stac_api.common.core import BulkTransactionsClient, CoreClient, TransactionsClient
+from stac_api.common.extensions import QueryExtension
+from stac_api.elastic_search.config import AsyncElasticsearchSettings
+from stac_api.elastic_search.database_logic import create_collection_index
 from stac_fastapi.api.app import StacApi
 from stac_fastapi.api.models import create_get_request_model, create_post_request_model
-from stac_fastapi.elasticsearch.config import AsyncElasticsearchSettings
-from stac_fastapi.elasticsearch.core import (
-    BulkTransactionsClient,
-    CoreClient,
-    TransactionsClient,
-)
-from stac_fastapi.elasticsearch.database_logic import create_collection_index
-from stac_fastapi.elasticsearch.extensions import QueryExtension
 from stac_fastapi.extensions.core import (  # FieldsExtension,
     ContextExtension,
     FieldsExtension,
@@ -28,6 +28,9 @@
 )
 from stac_fastapi.types.config import Settings
 
+# # Assuming your tests are in the 'tests' directory at the same level as 'stac_fastapi'
+# sys.path.append(str(Path(__file__).parent.parent))
+
 DATA_DIR = os.path.join(os.path.dirname(__file__), "data")
 
 
diff --git a/stac_fastapi/elasticsearch/tests/data/test_collection.json b/stac_api/tests/data/test_collection.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/data/test_collection.json
rename to stac_api/tests/data/test_collection.json
diff --git a/stac_fastapi/elasticsearch/tests/data/test_item.json b/stac_api/tests/data/test_item.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/data/test_item.json
rename to stac_api/tests/data/test_item.json
diff --git a/stac_fastapi/elasticsearch/tests/extensions/cql2/example01.json b/stac_api/tests/extensions/cql2/example01.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/extensions/cql2/example01.json
rename to stac_api/tests/extensions/cql2/example01.json
diff --git a/stac_fastapi/elasticsearch/tests/extensions/cql2/example04.json b/stac_api/tests/extensions/cql2/example04.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/extensions/cql2/example04.json
rename to stac_api/tests/extensions/cql2/example04.json
diff --git a/stac_fastapi/elasticsearch/tests/extensions/cql2/example05a.json b/stac_api/tests/extensions/cql2/example05a.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/extensions/cql2/example05a.json
rename to stac_api/tests/extensions/cql2/example05a.json
diff --git a/stac_fastapi/elasticsearch/tests/extensions/cql2/example06b.json b/stac_api/tests/extensions/cql2/example06b.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/extensions/cql2/example06b.json
rename to stac_api/tests/extensions/cql2/example06b.json
diff --git a/stac_fastapi/elasticsearch/tests/extensions/cql2/example08.json b/stac_api/tests/extensions/cql2/example08.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/extensions/cql2/example08.json
rename to stac_api/tests/extensions/cql2/example08.json
diff --git a/stac_fastapi/elasticsearch/tests/extensions/cql2/example09.json b/stac_api/tests/extensions/cql2/example09.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/extensions/cql2/example09.json
rename to stac_api/tests/extensions/cql2/example09.json
diff --git a/stac_fastapi/elasticsearch/tests/extensions/cql2/example1.json b/stac_api/tests/extensions/cql2/example1.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/extensions/cql2/example1.json
rename to stac_api/tests/extensions/cql2/example1.json
diff --git a/stac_fastapi/elasticsearch/tests/extensions/cql2/example10.json b/stac_api/tests/extensions/cql2/example10.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/extensions/cql2/example10.json
rename to stac_api/tests/extensions/cql2/example10.json
diff --git a/stac_fastapi/elasticsearch/tests/extensions/cql2/example14.json b/stac_api/tests/extensions/cql2/example14.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/extensions/cql2/example14.json
rename to stac_api/tests/extensions/cql2/example14.json
diff --git a/stac_fastapi/elasticsearch/tests/extensions/cql2/example15.json b/stac_api/tests/extensions/cql2/example15.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/extensions/cql2/example15.json
rename to stac_api/tests/extensions/cql2/example15.json
diff --git a/stac_fastapi/elasticsearch/tests/extensions/cql2/example17.json b/stac_api/tests/extensions/cql2/example17.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/extensions/cql2/example17.json
rename to stac_api/tests/extensions/cql2/example17.json
diff --git a/stac_fastapi/elasticsearch/tests/extensions/cql2/example18.json b/stac_api/tests/extensions/cql2/example18.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/extensions/cql2/example18.json
rename to stac_api/tests/extensions/cql2/example18.json
diff --git a/stac_fastapi/elasticsearch/tests/extensions/cql2/example19.json b/stac_api/tests/extensions/cql2/example19.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/extensions/cql2/example19.json
rename to stac_api/tests/extensions/cql2/example19.json
diff --git a/stac_fastapi/elasticsearch/tests/extensions/cql2/example20.json b/stac_api/tests/extensions/cql2/example20.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/extensions/cql2/example20.json
rename to stac_api/tests/extensions/cql2/example20.json
diff --git a/stac_fastapi/elasticsearch/tests/extensions/cql2/example21.json b/stac_api/tests/extensions/cql2/example21.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/extensions/cql2/example21.json
rename to stac_api/tests/extensions/cql2/example21.json
diff --git a/stac_fastapi/elasticsearch/tests/extensions/cql2/example22.json b/stac_api/tests/extensions/cql2/example22.json
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/extensions/cql2/example22.json
rename to stac_api/tests/extensions/cql2/example22.json
diff --git a/stac_fastapi/elasticsearch/tests/extensions/test_filter.py b/stac_api/tests/extensions/test_filter.py
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/extensions/test_filter.py
rename to stac_api/tests/extensions/test_filter.py
diff --git a/stac_fastapi/elasticsearch/tests/resources/__init__.py b/stac_api/tests/resources/__init__.py
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/resources/__init__.py
rename to stac_api/tests/resources/__init__.py
diff --git a/stac_fastapi/elasticsearch/tests/resources/test_collection.py b/stac_api/tests/resources/test_collection.py
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/resources/test_collection.py
rename to stac_api/tests/resources/test_collection.py
diff --git a/stac_fastapi/elasticsearch/tests/resources/test_conformance.py b/stac_api/tests/resources/test_conformance.py
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/resources/test_conformance.py
rename to stac_api/tests/resources/test_conformance.py
diff --git a/stac_fastapi/elasticsearch/tests/resources/test_item.py b/stac_api/tests/resources/test_item.py
similarity index 99%
rename from stac_fastapi/elasticsearch/tests/resources/test_item.py
rename to stac_api/tests/resources/test_item.py
index 5b382873..88f23402 100644
--- a/stac_fastapi/elasticsearch/tests/resources/test_item.py
+++ b/stac_api/tests/resources/test_item.py
@@ -9,11 +9,11 @@
 import ciso8601
 import pystac
 import pytest
+from common.core import CoreClient
+from common.datetime_utils import now_to_rfc3339_str
 from geojson_pydantic.geometries import Polygon
 from pystac.utils import datetime_to_str
 
-from stac_fastapi.elasticsearch.core import CoreClient
-from stac_fastapi.elasticsearch.datetime_utils import now_to_rfc3339_str
 from stac_fastapi.types.core import LandingPageMixin
 
 from ..conftest import create_item, refresh_indices
diff --git a/stac_fastapi/elasticsearch/tests/resources/test_mgmt.py b/stac_api/tests/resources/test_mgmt.py
similarity index 100%
rename from stac_fastapi/elasticsearch/tests/resources/test_mgmt.py
rename to stac_api/tests/resources/test_mgmt.py
diff --git a/stac_fastapi/elasticsearch/setup.cfg b/stac_fastapi/elasticsearch/setup.cfg
deleted file mode 100644
index 7a42432c..00000000
--- a/stac_fastapi/elasticsearch/setup.cfg
+++ /dev/null
@@ -1,2 +0,0 @@
-[metadata]
-version = attr: stac_fastapi.elasticsearch.version.__version__