{"id":28125,"library":"quacc","title":"quacc","description":"A platform for high-throughput, database-driven quantum chemistry and computational materials science. Current version: 1.2.6. Release cadence: monthly.","status":"active","version":"1.2.6","language":"python","source_language":"en","source_url":"https://github.com/QuantumChemistryAI/quacc","tags":["quantum-chemistry","materials-science","high-throughput","workflow","ASE","pymatgen"],"install":[{"cmd":"pip install quacc","lang":"bash","label":"Install from PyPI"}],"dependencies":[{"reason":"Required for Atoms objects and calculators","package":"ase","optional":false},{"reason":"Required for structure manipulation and file parsing","package":"pymatgen","optional":false},{"reason":"Required for graph-based workflows","package":"networkx","optional":false}],"imports":[{"note":"Flow is re-exported from the top-level package since v1.0","wrong":"from quacc.flow import Flow","symbol":"Flow","correct":"from quacc import Flow"},{"note":"get is available at top level to simplify usage","wrong":"from quacc.database import get","symbol":"get","correct":"from quacc import get"},{"note":"Common but not necessary; top-level API is designed to be small","wrong":"import quacc as qc","symbol":"quacc","correct":"import quacc"}],"quickstart":{"code":"import os\nos.environ['QUACC_DB_FILE'] = os.environ.get('QUACC_DB_FILE', 'quacc.db')\nfrom quacc import Flow, get, recipe\n\n# Define a simple relaxation workflow\n@recipe\ndef relax(atoms, calculator):\n    atoms.calc = calculator\n    atoms.get_potential_energy()\n    return atoms\n\n# Run the flow\nflow = Flow()\nflow.add(relax, atoms=...)\nflow.run()","lang":"python","description":"Basic usage: define a recipe and run it in a Flow."},"warnings":[{"fix":"Export your old data using quacc<1.0 and re-import with quacc>=1.0.","message":"In v1.0, the database backend was changed from SQLite to a custom JSON-based store. Existing databases are not compatible.","severity":"breaking","affected_versions":"<1.0"},{"fix":"Set os.environ['QUACC_DB_FILE'] = 'my_db.json' before importing quacc.","message":"The QUACC_DB_FILE environment variable must be set before importing quacc, otherwise a temporary file is used.","severity":"gotcha","affected_versions":"all"},{"fix":"Use from quacc import get, put instead of from quacc.database import get, put.","message":"The quacc.database module is deprecated in favor of top-level functions.","severity":"deprecated","affected_versions":">=1.0,<2.0"}],"env_vars":null,"last_verified":"2026-05-09T00:00:00.000Z","next_check":"2026-08-07T00:00:00.000Z","problems":[{"fix":"Upgrade Python to 3.11 or higher, then pip install quacc","cause":"quacc requires Python >=3.11","error":"ModuleNotFoundError: No module named 'quacc'"},{"fix":"Use `from quacc import Flow` (not `from quacc.flow import Flow`). Upgrade to >=1.0.","cause":"Importing from the wrong location or using an older version","error":"AttributeError: module 'quacc' has no attribute 'Flow'"},{"fix":"Upgrade quacc to >=1.2.0: pip install --upgrade quacc","cause":"The @recipe decorator was introduced in v1.2.0","error":"ValueError: Unknown recipe decorator"}],"ecosystem":"pypi","meta_description":null,"install_score":null,"install_tag":null,"quickstart_score":null,"quickstart_tag":null}