Compatibility and migration

Supported compatibility contract (0.2.0 staging)

  • Scripts written against 0.1.x that construct Hotpants / HotpantsConfig without new keyword arguments continue to work.

  • Default backend remains the C extension (use_c_extension=True).

  • Default stamp selection remains classic stamp_mode="grid".

  • Public exports from 0.1.2 (KernelModel, convolve_template) remain available.

  • Return products from run_pipeline() / get_final_outputs() keep the established keys (difference image, convolved image, background, noise, mask, stats, kernel solution, convolution direction).

What is new in 0.2.0 (staging on development)

  • Pure Python backend via use_c_extension=False

  • Oversampled templates via oversample > 1

  • Connected-region stamps via stamp_mode="connected_regions"

  • Expanded documentation for backends, parity, and connected stamps

Migration tips

  1. Keep production pipelines on the C default until you have validated pure Python on your data (see C vs pure Python parity policy).

  2. Opt into new modes explicitly; do not rely on changed defaults.

  3. When comparing C vs pure, pin the same HotpantsConfig and inputs.