Worked on cross-repository performance and JSON formatting enhancements for the ruby/ruby and ruby/json projects, focusing on numeric-heavy workloads. Ported an optimized integer formatting algorithm from C++ to C, writing directly to buffers to reduce memory allocations and achieve a 32% speedup in benchmarks. Improved JSON serialization by ensuring integer-like floats consistently end with .0, enhancing interoperability and output stability. Updated documentation and licensing to reflect these changes, particularly for the fpconv integration. Utilized C, Ruby, and Markdown, applying skills in algorithm implementation, performance optimization, and Ruby C extensions to deliver measurable improvements in throughput and downstream system compatibility.