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TimefoldAI
timefold-solver
Java2023–2025
TimefoldAI / timefold-solver

timefold-solver

The open source Solver AI for Java and Kotlin to optimize scheduling and routing. Solve the vehicle routing problem, employee rostering, task assignment, maintenance scheduling and other planning problems.

3Distinct people
6Mentions
0Explicit recommenders
1.9KGitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

The open source Solver AI for Java and Kotlin to optimize scheduling and routing. Solve the vehicle routing problem, employee rostering, task assignment, maintenance scheduling and other planning problems.

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 8–Nov 15 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/15/2026, 9:28:18 AM 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 month6 dated mentions

Observed mentions: 2023-09-11 09:16:21 UTC to 2025-04-28 17:19:51 UTC.

0122023-09-01 00:00:00 UTC to 2023-10-01 00:00:00 UTC (exclusive): 1 mentions; 1 submissions, 0 commentsSep 20232023-10-01 00:00:00 UTC to 2023-11-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-11-01 00:00:00 UTC to 2023-12-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-12-01 00:00:00 UTC to 2024-01-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-01-01 00:00:00 UTC to 2024-02-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-02-01 00:00:00 UTC to 2024-03-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-03-01 00:00:00 UTC to 2024-04-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-04-01 00:00:00 UTC to 2024-05-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-05-01 00:00:00 UTC to 2024-06-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-06-01 00:00:00 UTC to 2024-07-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 commentsJun 20242024-07-01 00:00:00 UTC to 2024-08-01 00:00:00 UTC (exclusive): 2 mentions; 0 submissions, 2 comments2024-08-01 00:00:00 UTC to 2024-09-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-09-01 00:00:00 UTC to 2024-10-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments2024-10-01 00:00:00 UTC to 2024-11-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-11-01 00:00:00 UTC to 2024-12-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2024-12-01 00:00:00 UTC to 2025-01-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-01-01 00:00:00 UTC to 2025-02-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-02-01 00:00:00 UTC to 2025-03-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 comments2025-03-01 00:00:00 UTC to 2025-04-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2025-04-01 00:00:00 UTC to 2025-05-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 commentsApr 2025

Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.

View mention counts and date ranges
UTC ranges include their start and exclude their end. Select a period to filter the source evidence.
PeriodStart (UTC)End (exclusive, UTC)MentionsSubmissionsComments
Sep 20232023-09-01 00:00:00 UTC2023-10-01 00:00:00 UTC110
Oct 20232023-10-01 00:00:00 UTC2023-11-01 00:00:00 UTC000
Nov 20232023-11-01 00:00:00 UTC2023-12-01 00:00:00 UTC000
Dec 20232023-12-01 00:00:00 UTC2024-01-01 00:00:00 UTC000
Jan 20242024-01-01 00:00:00 UTC2024-02-01 00:00:00 UTC000
Feb 20242024-02-01 00:00:00 UTC2024-03-01 00:00:00 UTC000
Mar 20242024-03-01 00:00:00 UTC2024-04-01 00:00:00 UTC000
Apr 20242024-04-01 00:00:00 UTC2024-05-01 00:00:00 UTC000
May 20242024-05-01 00:00:00 UTC2024-06-01 00:00:00 UTC000
Jun 20242024-06-01 00:00:00 UTC2024-07-01 00:00:00 UTC000
Jul 20242024-07-01 00:00:00 UTC2024-08-01 00:00:00 UTC202
Aug 20242024-08-01 00:00:00 UTC2024-09-01 00:00:00 UTC000
Sep 20242024-09-01 00:00:00 UTC2024-10-01 00:00:00 UTC101
Oct 20242024-10-01 00:00:00 UTC2024-11-01 00:00:00 UTC000
Nov 20242024-11-01 00:00:00 UTC2024-12-01 00:00:00 UTC000
Dec 20242024-12-01 00:00:00 UTC2025-01-01 00:00:00 UTC000
Jan 20252025-01-01 00:00:00 UTC2025-02-01 00:00:00 UTC000
Feb 20252025-02-01 00:00:00 UTC2025-03-01 00:00:00 UTC101
Mar 20252025-03-01 00:00:00 UTC2025-04-01 00:00:00 UTC000
Apr 20252025-04-01 00:00:00 UTC2025-05-01 00:00:00 UTC101

What Hacker News says

2 sources
I written a data structure for grouping intervals into disjoint connected clusters. Each cluster in the data structure is a connected component of the interval space (see https://en.wikipedia.org/wiki/Connected_space for the definition of connected component). This is useful to determining maximum concurrent use of a resource; for instance, if there are only 3 projectors, a maximum of 3 lessons that require projectors can overlap at any given time. The basic idea is to use a sorted multi-set of each interval's end points, doing case analysis on insertion to determine what interval clusters to merge; removal re-computes the entire cluster the removed range was in, splitting the cluster into two or more when gaps are encountered. For the implementation, see https://github.com/TimefoldAI/timefold-solver/blob/main/core... As a side effect of
Read the rest
keeping track of connected clusters, the data structure also keeps track of gaps between clusters (which could be used to find the next availability). For how it is used in practice, there an example in Timefold's docs: https://docs.timefold.ai/timefold-solver/latest/constraints-... A simpler algorithm can be used when each interval represent a time grain (fixed length, no two intervals overlap). See https://github.com/TimefoldAI/timefold-solver/tree/main/core... for that.
In Ask HN: Fast data structures for disjoint intervals?
Let us know how we can improve! Feel free to start a discussion (https://github.com/TimefoldAI/timefold-solver/discussions) or submit an issue (https://github.com/TimefoldAI/timefold-solver-python/issues). We aim to treat Python as a first-class citizen (while keeping it maintainable). For instance, many of the Java methods are mapped to properties on the Python classes with more Pythonic names (see `ScoreExplanation` for an example). I suspect what gives the Java smell is probably the `SolverFactory`/`SolverConfig`, which is a lot of boilerplate code. A lot of the code can be generated, although we would need to design an API for that. The fluent (method chaining) API might also be giving the Java smell; I don't see many fluent API being used in Python. In particular, needing to either end lines with `\` or surround the statement with br
Read the rest
ackets make long fluent chains annoying to use. This is harder to change, since there is no Pythonic alternative that I know of for method chaining.
In A practical introduction to constraint programming using CP-SAT and Python

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