Pulumi recently improved the performance of its Python programs by addressing a bug related to the Python default future executor, which was limiting the concurrency of resource provisioning. After implementing a custom ThreadExecutor to respect user-defined parallelism settings, Pulumi Python programs experienced a significant speedup, achieving performance parity with Pulumi Node.js. Experimental tests showed that after the patch, Pulumi Python ran over three times faster than before, and slightly outperformed Pulumi TypeScript in similar benchmarks. The fix was introduced in Pulumi v3.44.3, ensuring that Python users automatically benefit from enhanced parallel execution without any additional configuration.