BUburntsushi·May 28, 2026
You win the naming contest. The project has been renamed: https://github.com/BurntSushi/bttf/pull/14
In Bttf is a command line datetime Swiss army knifeBurntSushi
bttf
Rust2025–2026
BurntSushi / bttf
bttf
A command line tool for datetime arithmetic, parsing, formatting and more.
2Distinct people
9Mentions
0Explicit recommenders
767GitHub stars
What to know before exploring
What it is
A command line tool for datetime arithmetic, parsing, formatting and more.
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.
No classified warning is attached to this page. Read the discussions before treating silence as approval.
Also in these discussions
No other repository is repeatedly linked in the same discussions.
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 month9 dated mentions
Observed mentions: 2025-05-12 14:07:44 UTC to 2026-05-28 15:17:27 UTC.
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 |
|---|---|---|---|---|---|
| May 2025 | 2025-05-01 00:00:00 UTC | 2025-06-01 00:00:00 UTC | 2 | 1 | 1 |
| Jun 2025 | 2025-06-01 00:00:00 UTC | 2025-07-01 00:00:00 UTC | 0 | 0 | 0 |
| Jul 2025 | 2025-07-01 00:00:00 UTC | 2025-08-01 00:00:00 UTC | 0 | 0 | 0 |
| Aug 2025 | 2025-08-01 00:00:00 UTC | 2025-09-01 00:00:00 UTC | 0 | 0 | 0 |
| Sep 2025 | 2025-09-01 00:00:00 UTC | 2025-10-01 00:00:00 UTC | 0 | 0 | 0 |
| Oct 2025 | 2025-10-01 00:00:00 UTC | 2025-11-01 00:00:00 UTC | 1 | 1 | 0 |
| Nov 2025 | 2025-11-01 00:00:00 UTC | 2025-12-01 00:00:00 UTC | 0 | 0 | 0 |
| Dec 2025 | 2025-12-01 00:00:00 UTC | 2026-01-01 00:00:00 UTC | 1 | 0 | 1 |
| Jan 2026 | 2026-01-01 00:00:00 UTC | 2026-02-01 00:00:00 UTC | 0 | 0 | 0 |
| Feb 2026 | 2026-02-01 00:00:00 UTC | 2026-03-01 00:00:00 UTC | 0 | 0 | 0 |
| Mar 2026 | 2026-03-01 00:00:00 UTC | 2026-04-01 00:00:00 UTC | 0 | 0 | 0 |
| Apr 2026 | 2026-04-01 00:00:00 UTC | 2026-05-01 00:00:00 UTC | 0 | 0 | 0 |
| May 2026 | 2026-05-01 00:00:00 UTC | 2026-06-01 00:00:00 UTC | 5 | 1 | 4 |
What Hacker News says
9 sourcesYeah this was before my time. I never did email from a terminal. Which probably explains why I was okay with naming it Biff.
In any case, I've renamed the project to bttf: https://github.com/BurntSushi/bttf/pull/14
In Bttf is a command line datetime Swiss army knifeYes!!! To spell it out (with the new biff -> bttf name):
$ bttf time seq monthly -w 2-tue -u 1y | bttf time fmt -f '%c'
Tue, Jun 9, 2026, 11:15:11 AM EDT
Tue, Jul 14, 2026, 11:15:11 AM EDT
Tue, Aug 11, 2026, 11:15:11 AM EDT
Tue, Sep 8, 2026, 11:15:11 AM EDT
Tue, Oct 13, 2026, 11:15:11 AM EDT
Tue, Nov 10, 2026, 11:15:11 AM EST
Tue, Dec 8, 2026, 11:15:11 AM EST
Tue, Jan 12, 2027, 11:15:11 AM EST
Tue, Feb 9, 2027, 11:15:11 AM EST
Tue, Mar 9, 2027, 11:15:11 AM EST
Tue, Apr 13, 2027, 11:15:11 AM EDT
Tue, May 11, 2027, 11:15:11 AM EDT
More examples here: https://github.com/BurntSushi/biff/blob/master/GUIDE.md#date...
Implementing the RFC 5545 recurrence rules was quite a lot of fun: https://github.com/BurntSushi/biff/blob/4c75d5cf6e09310e74ca...
I'm quite proud of it, because if you look at t
Read the rest
he implementation, it's almost entirely about dealing with the specification rules. All of the datetime bullshit (including handling time zones) is all deferred to Jiff.
Plus, the tests are nearly 4,000 lines. While the implementation is 2,000 lines.
Yes! dateutils is great! I have a comparison about it here: https://github.com/BurntSushi/biff/blob/master/COMPARISON.md...
The comparison with GNU date is also likely informative.
In Bttf is a command line datetime Swiss army knifeBttf is a command line datetime Swiss army knife
183 points · Open discussionHave you seen Biff? It can do this and it will use your system's tzdb, unlike chrono. https://github.com/BurntSushi/biff
In Show HN: Nanji – A minimal Rust CLI for timezone conversionBiff is a command line datetime Swiss army knife
5 points · Open discussionBiff is CLI for datetime arithmetic, parsing, formatting, rounding and more
8 points · Open discussion