{"library":"localstack-core","title":"LocalStack Core","description":"LocalStack Core is the foundational Python library and runtime for LocalStack, a robust cloud service emulator that allows developers to run AWS applications and Lambdas entirely on their local machine or in CI environments without connecting to a remote cloud provider. The library underpins the LocalStack CLI and Docker container, providing the core emulation capabilities. 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Ensure LocalStack CLI is installed: pip install localstack\n# 2. Start LocalStack (requires Docker): localstack start\n# 3. Install the extension using its entry point configuration (e.g., in setup.py/cfg)\n#    or directly from a file/git repo using `localstack extensions install`.\n#    For demonstration, if packaged:\n#    localstack extensions install my-ready-announcer\n#    (This example shows the Python code for an extension, not how to run a standalone script with localstack-core)\n\n# A more direct, though less common, 'quickstart' for *using* LocalStack from Python\n# would involve the AWS SDK (boto3) configured to talk to LocalStack endpoints.\n# This is typically done with `awslocal` or direct endpoint configuration.\n# Example for boto3 (requires LocalStack running):\n# import boto3\n# import os\n#\n# os.environ['AWS_ACCESS_KEY_ID'] = 'test'\n# os.environ['AWS_SECRET_ACCESS_KEY'] = 'test'\n# os.environ['AWS_DEFAULT_REGION'] = 'us-east-1'\n#\n# s3_client = boto3.client('s3', endpoint_url='http://localhost:4566')\n# try:\n#     response = s3_client.list_buckets()\n#     print(f\"S3 Buckets (LocalStack): {response['Buckets']}\")\n# except Exception as e:\n#     print(f\"Error connecting to LocalStack S3: {e}\")","lang":"python","description":"This quickstart demonstrates how to define a simple LocalStack extension using the `localstack-core` library's extension API. LocalStack extensions are Python classes that implement specific lifecycle hooks. For general interaction with LocalStack-emulated AWS services from Python, `boto3` is used and configured to point to LocalStack's local endpoints, typically at `http://localhost:4566`. Ensure Docker is running and LocalStack is started (e.g., via `localstack start`) before attempting to interact with emulated AWS services.","tag":null,"tag_description":null,"last_tested":null,"results":[]},"compatibility":{"tag":null,"tag_description":null,"last_tested":"2026-05-14","installed_version":"4.9.2","pypi_latest":"2026.3.0","is_stale":true,"summary":{"python_range":"3.10–3.9","success_rate":75,"avg_install_s":7.6,"avg_import_s":null,"wheel_type":"wheel"},"results":[{"runtime":"python:3.10-alpine","python_version":"3.10","os_libc":"alpine (musl)","variant":"localstack","exit_code":0,"wheel_type":null,"failure_reason":null,"import_side_effects":null,"install_time_s":null,"import_time_s":null,"mem_mb":null,"disk_size":null},{"runtime":"python:3.10-alpine","python_version":"3.10","os_libc":"alpine 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