Python 3.15 is now available with a new lazy keyword for deferred module imports, reducing startup costs. Ruff v0.17 introduces rules to manage lazy imports, while uv adds a preview feature for lazy build backend imports that can speed up wheel builds by up to 18%.
Python 3.15 introduces lazy imports, allowing modules to load only when actually used rather than at startup. A benchmark showed the version command startup time dropped from 295ms to 20ms (35-fold reduction in import costs), though errors now occur at runtime rather than startup.
OCaml's module system with separate interface (.mli) and implementation (.ml) files is well-suited for agentic programming. By defining module interfaces first, coding agents can fill in implementations for well-specified holes rather than processing massive codebases, and interfaces can be validated through test clients before implementation begins.
Python 3.15 introduces lazy imports, which defer module loading until first use rather than at startup. Testing shows dramatic speedups: version printing improved 15x (295ms to 20ms) and a mean calculation 12x faster, though errors now occur at runtime rather than startup.