I built binary serializer for Pydantic models that's up to 7× smaller than JSON

1 day ago 1

PyByntic extends Pydantic with binary-typed fields and automatic byte-level serialization. Define models using familiar Pydantic syntax and turn them into compact binary payloads with full control over layout and numeric precision.

Binary Serialization: Convert Pydantic models to compact binary format
Type Safety: Full type annotations with custom binary types
Nested Models: Support for nested models and lists
Custom Encoders: Support for compression and custom encoding
Size Efficiency: Significantly smaller than JSON serialization

# Install dev dependencies poetry install --with dev # Run tests poe test # Format code poe autoformat

from pybyntic import AnnotatedBaseModel from pybyntic.types import UInt32, String, Bool, Date from typing import Annotated import datetime class User(AnnotatedBaseModel): user_id: Annotated[int, UInt32] username: Annotated[str, String] is_active: Annotated[bool, Bool] join_date: Annotated[datetime.date, Date] # Create and serialize user = User( user_id=123, username='admin', is_active=True, join_date=datetime.date.today() ) # Serialize to bytes serialized = user.serialize() # Deserialize from bytes deserialized = User.deserialize(serialized)

See the examples/ directory for more comprehensive examples including:

Basic serialization
List handling
Nested models
Compression
Benchmarking

Type Name Format / Encoding Python Type Returned Notes

Skip	— (no-op)	None	Skips field
Bool	b (1 byte)	bool	Writes 1 or 0
Int8	b	int	Signed 8-bit integer
Int16	h	int	Signed 16-bit integer
Int32	i	int	Signed 32-bit integer
Int64	q	int	Signed 64-bit integer
UInt8	B	int	Unsigned 8-bit integer
UInt16	H	int	Unsigned 16-bit integer
UInt32	I	int	Unsigned 32-bit integer
UInt64	Q	int	Unsigned 64-bit integer
UInt128	2× Q (hi/lo)	int	128-bit unsigned integer, stored as 2×64-bit
Float32	f	float	IEEE754 single precision
Float64	d	float	IEEE754 double precision
String	varint + bytes	str	UTF-8 string, with varint length prefix
StringJson	varint + bytes	dict	UTF-8 JSON, decoded via json.loads
DateTime32	I	datetime (UTC)	Seconds since epoch
DateTime64[p]	Q	datetime (UTC)	Timestamp in 10^-p seconds precision (default p=3)
Date	H	date	Days since 1970-01-01

Implementing Custom Types

Example of a type implementation:

from pybyntic.buffer import Buffer class Bool: @classmethod def read(cls, buf: Buffer): return bool(buf.read_formated("b")) @classmethod def write(cls, buf: Buffer, value): buf.write_formated("b", 1 if value else 0)

Type classes must implement read and write class methods to handle serialization and deserialization. Read methods receive a Buffer instance for byte operations, and write methods receive a Buffer and the value to serialize.

The project includes comprehensive tests covering: