Eno enhanced the ruby/ruby and ruby/json repositories by implementing a faster integer formatting algorithm in C, ported from a C++ source, which writes directly to buffers to reduce memory allocations and achieved a 32% speedup in benchmarks. He addressed JSON numeric formatting by ensuring integer-like floats consistently end with .0, improving downstream interoperability and predictability. Eno also updated documentation and licensing to clarify changes related to the fpconv integration. His work demonstrated depth in algorithm implementation, C programming, and JSON serialization, delivering measurable performance improvements and more stable numeric representations for numeric-heavy Ruby workloads and dependent systems.