pip install hydra-core --upgrade Happy composing! Let us know in the comments if you have found the 1.2 resolver syntax tricky—I will be writing a deep dive on that next week.
# Old (Hydra 1.1) @hydra.main(config_path="conf", config_name="config") def main(cfg): ... def main(): cfg = hydra.initialize_and_run(config_path="conf", config_name="config", task_function=my_task) hydra 1.2
Navigating the Labyrinth: What’s New in Hydra 1.2 pip install hydra-core --upgrade Happy composing
Version 1.2 introduces for certain resolver functions. Early benchmarks show a 40% reduction in instantiation time for large config suites. 5. Deprecation of hydra.main This is the breaking change you need to watch for. The decorator @hydra.main() has been a staple since day one. It now throws a DeprecationWarning . In Hydra 2.0 (planned for Q3 2026), it will be removed. def main(): cfg = hydra
This change allows for better type checking and allows you to run Hydra inside Jupyter Notebooks (finally!) without weird hacks. Yes, but carefully. If you are starting a new project today, use Hydra 1.2 . The new composition rules and Jupyter support are worth it.
If you are on a legacy pipeline of 10,000+ lines of configs, pin your version to hydra-core==1.1.2 for now, but plan the migration. The deprecation of hydra.main means you will need to refactor your entry point logic.