AI & ML Practical Magic

Stop using Protocol Buffers; switching to a simple fixed-length format can boost your decoding speed by up to 1,600x.

April 14, 2026

Original Paper

Simplicity Scales

Andrew Sampson, Yuta Saito, Ronny Chan

arXiv · 2604.09591

The Takeaway

By using Bebop—a fixed-width serialization format—the system eliminates the data-dependent CPU branches that slow down variable-length encodings like Protobuf or JSON. It proves that modern hardware efficiency favors extreme simplicity and predictability over 'clever' variable-length compression.

From the abstract

The dominant data interchange formats encode integers using a variable number of bytes or represent floating-point numbers as variable-length UTF-8 strings. The decoder must inspect each byte for a continuation bit or parse each character individually, producing data-dependent branches that stall modern CPU pipelines. Protocol Buffers pays this cost on every integer, field tag, and length prefix. JSON pays it on every value.We present Bebop, a serialization format where every data type uses a fi