Protobufin

Protobufin is a fictional data-serialization framework designed to resemble Protocol Buffers. It presents an approach to encoding structured data in a compact binary form using schemas to control layout and compatibility. It is not an officially released project and is commonly used in educational or hypothetical discussions to illustrate concepts of schema-based serialization.

Protobufin uses an interface definition language called PIDL that defines messages and fields with numeric tags. Fields can be optional or repeated, with default values; messages are nested and can be embedded. Encoding relies on a varint-based representation for integers, zigzag encoding for signed numbers, length-delimited fields for strings and nested messages, and support for fixed-width types. The design emphasizes backward- and forward-compatibility by preserving tag numbers and optional field presence across schema evolution.

A key part of the Protobufin concept is its tooling and runtime. A PIDL compiler generates language-specific bindings, while a runtime library provides serialization, deserialization, reflection, and streaming access. The runtime is described as prioritizing zero-copy deserialization and progressive decoding to handle large payloads efficiently. It also includes validation hooks for schema constraints and field-level metadata to aid in data governance and debugging.

Use cases for Protobufin in theory include microservices communication, data streaming, and inter-process messaging where compact binary size and cross-language interoperability are advantageous. As a fictional construct, it remains a topic of discussion in academic or demonstration contexts rather than a deployed technology with an established ecosystem, governance, or production tooling.

See also Protocol Buffers, Cap'n Proto, FlatBuffers, Data serialization.