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kaitaistruct

0.117.2M downloads/mokaitai-io/kaitai_struct_python_runtime ↗New releases in your daily digest, changelog included.

Kaitai Struct declarative parser generator for binary data: runtime library for Python

Last release 1 years ago
08 Sep 2025
Release timing varies
gaps range from 2 months to 3.2 years
Some releases are documented
notes for 4 of 9 stable releases
Nothing withdrawn
no release was ever pulled
10 years old
9 releases · first in 2016

Release timeline

9 releases since 2016

20162018202020222024

Releases

0.118 Sept 2025
This project publishes no release notes. Between 0.10 and v0.11 there were 49 commits, 44 of them substantive:
This project publishes no release notes. Between 0.10 and v0.11 there were 49 commits, 44 of them substantive:

Remove redundant wheel dep

setup.cfg: add metadata.project_urls (#71)

Convert section title comments to code-folding regions

Add write methods and classes (bit ints not implemented yet)

Add write_bits_int_{be,le}() and write_align_to_byte()

Invoke {,write_}align_to_byte() in all byte-aligned operations

Emulate fixed-length stream when writing

close(): flush unwritten bits before closing

Update pos() and is_eof() for {read,write}bits_int*() parity

LICENSE: bump copyright year

Bump package version and API version to 0.11

Bump package version to 0.11.dev1

Add Python 3.11 tag to setup.cfg (#74)

size(): fix returning None in Python 2 for 'file' objects

Support writing to 'file' objects in Python 2

is_eof(): fix for write-only streams

write_bits_int_{be,le}(): raise EOF errors proactively

write_align_to_byte(): clear bit buffer even if the write fails

_write_bytes_not_aligned(): use self._io.tell() in EOF check

Validation*Error: only include "at pos X: " if io is not None

…and 24 more.
0.109 Jul 2022
For small reads, the new code that tries to avoid unnecessary reads is noticeably slower than the previous code that reads unconditionally. In the wor

For small reads, the new code that tries to avoid unnecessary reads is
noticeably slower than the previous code that reads unconditionally. In
the worst case (1-byte reads), the new code is 13 times as slow as the
previous implementation. The potential memory/IO savings only become
worth it for larger reads, where the performance difference disappears.

Co-authored-by: Petr Pucil petr.pucil@seznam.cz

Open source →

Additional notes

This project publishes no release notes. Between 0.9 and 0.10 there were 30 commits, 28 of them substantive:

Simplify bytes_strip_right and bytes_terminate implementations
Fix pycodestyle violation
Extend user-defined exception from Exception instead of BaseException to follow Python oficial docummentation and make it possible to catch it using a generic Exception
Convert README markup to Markdown
Rename README.{rst => md}
Add PyPI package version badge
Add more PyPI badges
Delete badges "format", "wheel" and "implementation"
README: cancel link of the "Python versions" badge
Readme: remove "downloads", "python versions" link
Minor improvements of int_from_byte() and byte_from_int()
Rewrite read_bits_int_{be,le}()
Fix "pycodestyle" violations from previous commit 427ea191
Add Python 3.8 through 3.10 classifiers to metadata
Deleted MANIFEST.in (#66)
read_bytes(): check if the request is satisfiable, change error msg
Add API_VERSION constant storing the runtime version as a tuple of ints (#49)
Fix read_bytes() in Python 2 on 'file' objects
read_bytes(): suppress PyCharm "Unbound local variable" inspection
Fixed pylint warnings (#56)

…and 8 more.

0.915 Oct 2020

See kaitai-io/kaitai_struct#435

Open source →

Additional notes

This project publishes no release notes. Between 0.8 and 0.9 there were 36 commits, 24 of them substantive:

pypi manifesto, adds Construct to keywords for mutual promotion
replaced struct.unpack with struct.Struct().unpack
Added .editorconfig
Fix whitespace
Now we store the metadata in setup.cfg.
Remove unused import (struct.unpack)
relative seek(-1,CUR) instead of seek(tell()-1)
Added resolve_enum, akin to Ruby implementation
Fix EOF check to ensure that we have no bits left in temporary storage too; bumped version and copyright year
Added system of exception
Add LICENSE file
Added ValidationLessThanError/ValidationGreaterThanError
Use io.open() instead of open() for consistency
Fix byte array operations
Added pycodestyle check using GH Actions
Fix style violations
Installation and usage instructions now live only in Python notes
Restrict compatible Python versions, as per https://github.com/kaitai-io/kaitai_struct/issues/695
Add ValidationNotAnyOfError
Add method read_bits_int_le

…and 4 more.

0.87 Feb 2018

Reverting change that broken ~13 tests

Open source →

Additional notes

This project publishes no release notes. Between 0.7 and 0.8 there were 16 commits, 10 of them substantive:

Note explicit support for Python 3.6
Fix blatant out-of-range iteration
More helper methods - from_bytes and from_io
cStringIO is ancient, modern python hides it
raising errors cleanup
read_bytes min amount is 0
KaitaiStream code cleanup (#18)
README converted into reST and updated
Bump copyright year
Reverting change that broken ~13 tests

0.722 Mar 2017

Refreshed links to point to actual resources

Open source →

Additional notes

This project publishes no release notes. Between 0.6 and 0.7 there were 8 commits, 8 of them substantive:

Removed string handling methods, added readBytesTerm
Implemented bytes_strip_right and bytes_terminate
Stop redefining built-in "bytes" thing
Added PEP-0396-style version
Fix code style: extra blank line required here
Pumped year
Derive version programmatically from kaitaistruct.py using version const
Refreshed links to point to actual resources

0.64 Feb 2017

This project publishes no release notes. Between 0.5 and 0.6 there were 9 commits, 7 of them substantive:

This project publishes no release notes. Between 0.5 and 0.6 there were 9 commits, 7 of them substantive:

ensure_fixed_contents: removed unnecessary len, we would use expected length now
Explicitly inherit object (Py2 compat)
Fixed string formatting in exception messages
Added simple implementation of read_bits_int
Style fix: use isinstance() instead of type() for type check
Implemented align_to_byte
Pumped version