THthesz·Oct 27, 2026
How does it compare to bzip3 [1]?
[1] https://github.com/iczelia/bzip3
Did this Claude-written free compressor take anything from bzip3?
In Free Compressor Written by Claude Out-Squeezes the Giants: ZSTD, Gzip and, Bsciczelia
bzip3
C2022–2026
iczelia / bzip3
bzip3
A better and stronger spiritual successor to bzip2.
10Distinct people
12Mentions
0Explicit recommenders
1.5KGitHub stars
What to know before exploring
What it is
A better and stronger spiritual successor to bzip2.
GitHub
Where it is used
No documented product use has been verified yet.
What people are saying
No recommendation phrase was found in the indexed comments.
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Also in these discussions
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This week on Hacker News
Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 3:56:07 PM UTC.
No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.
Mentions over time
HN mentions by year12 dated mentions
Observed mentions: 2022-05-10 07:19:12 UTC to 2026-10-27 17:29:06 UTC.
* An incomplete calendar period is marked with an outlined bar. Its count is not directly comparable with a full period.
Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.
View mention counts and date ranges
| Period | Start (UTC) | End (exclusive, UTC) | Mentions | Submissions | Comments |
|---|---|---|---|---|---|
| 2022 | 2022-01-01 00:00:00 UTC | 2023-01-01 00:00:00 UTC | 4 | 1 | 3 |
| 2023 | 2023-01-01 00:00:00 UTC | 2024-01-01 00:00:00 UTC | 0 | 0 | 0 |
| 2024 | 2024-01-01 00:00:00 UTC | 2025-01-01 00:00:00 UTC | 1 | 0 | 1 |
| 2025 | 2025-01-01 00:00:00 UTC | 2026-01-01 00:00:00 UTC | 1 | 1 | 0 |
| 2026 (partial) | 2026-01-01 00:00:00 UTC | 2027-01-01 00:00:00 UTC | 6 | 1 | 5 |
What Hacker News says
12 sourcesTool author here. Sure, out of all bait in this thread I will bite this one. Curiously, it seems like Konstantinos has opened this ticket, i.e. https://github.com/iczelia/bzip3/issues/177, and open-sourced his algorithm here -- https://codeberg.org/kagiannis/gdcc-2021. As the allegation is very serious, I will also copy the edited version of this response to my website.
I have not seen his tool before, or even was aware of it. However, once you take a closer look, you notice that these two tools could not be more dissimilar. Agiannis' compressor uses a compact context representation to group bytes, followed by RLE and prefix coding. Bzip3 combines repetition removal (here via a run-length code -- prior to the BWT -- and LZP of Charles Bloom), a full Burrows–Wheeler transform, and a richer (thus slower) statistical arithmetic coder.
Read the rest
The use of RLE for post-coding the BWT output dates as far back to Julian Seward, perhaps even further. The RLE and LZP are applied before the Burrows-Wheeler transform (as opposed to the implementation in `text', which makes a big difference). Bzip3 uses a proper SAIS library for the forward and backward transforms. Konstantinos' entropy coder seems to use FPC (bytewise prefix codes over adaptively selected subblocks), bzip3 uses an idea similar to this of bcm, which itself descends from Mahoney and ancient work of JS Vitter on arihtmetic coding, where a bitwise arihtmetic coder is input mixed probability estimates from exponential-moving averages with probability refinement.
You are welcome to conduct your own analysis, but this is the gist of it -- perhaps Konstantinos has convinced himself that he had invented run-length coding?
An interesting unintentional benchmark is to go to https://github.com/iczelia/bzip3/releases and see to what degree bzip3 compresses its own release archives; and go to https://github.com/iczelia/bzip3/blob/master/.github/workflo... to see what options have been chosen for the other compressors here.
In bzip3I wonder why people think there is only 1 bzip (which seems to be bzip2), when the original bzip exists: https://unix.stackexchange.com/a/125803 and also bzip3: https://github.com/iczelia/bzip3
In An ode to bzipBzip3: A spiritual successor to BZip2
355 points · Open discussionKamila Szewczyk is working on a bzip3 to improve the state-of-the-art in the domain of compressors based on Burrows-Wheeler:
https://github.com/kspalaiologos/bzip3
I’m keeping fingers crossed for the project. Especially given that the author is 19 and her best work is yet to come.
In Bzip2 Format Specification (2016) [pdf]Regarding zstd: I've just discovered bzip3.
https://github.com/kspalaiologos/bzip3
In Sapling: A new source control system with Git-compatible clientThe code has, at https://github.com/kspalaiologos/bzip3/blob/bf2f0e02fd59f4c4... :
} else if (argv[i][1] == 'j') {
workers = atoi(argv[i + 1]);
i++;
If the last argument is "-j6" then this will read past the end of the allocated argv strings and try to do atoi(NULL):
% ./bzip3 -j3 < README.md
Segmentation fault
"-j6" is standard getopt() behavior, and the default expected behavior from Unix/POSIX systems.
In Bzip3 – A better and stronger spiritual successor to bzip2Good work!
I was also confused with faster speed claims than bzip2, and then saw the discussion in the issue: https://github.com/kspalaiologos/bzip3/issues/2
In Bzip3 – A better and stronger spiritual successor to bzip2Bzip3 – A better and stronger spiritual successor to bzip2
158 points · Open discussion