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docs/archive/fast-engine-next-optimizations.md

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+# Fast Engine Follow-up Optimizations
+
+The current fast engine exposes Python wrappers for testing and debugging, but
+serious traversal code should use the Cython `fast.pxd` API directly.
+
+Deferred work:
+
+1. Consider direct NumPy or feature-buffer output for RL pipelines instead of
+   building Python lists and converting later.
+2. Consider a single contiguous allocation for state arrays after profiling the
+   simpler separate-allocation layout.