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TomasMikula
libretto
Scala2023–2025
TomasMikula / libretto

libretto

Declarative concurrency and stream processing library for Scala

2Distinct people
2Mentions
0Explicit recommenders
215GitHub stars
REPOSITORY AT A GLANCE

What to know before exploring

What it is

Declarative concurrency and stream processing library for Scala

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, 1:49:46 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 month2 dated mentions

Observed mentions: 2023-07-16 05:24:33 UTC to 2025-02-20 18:09:02 UTC.

012023-07-01 00:00:00 UTC to 2023-08-01 00:00:00 UTC (exclusive): 1 mentions; 0 submissions, 1 commentsJul 20232023-08-01 00:00:00 UTC to 2023-09-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-09-01 00:00:00 UTC to 2023-10-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 comments2023-10-01 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 commentsApr 20242024-05-01 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 comments2024-07-01 00:00:00 UTC to 2024-08-01 00:00:00 UTC (exclusive): 0 mentions; 0 submissions, 0 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): 0 mentions; 0 submissions, 0 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; 1 submissions, 0 commentsFeb 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
Jul 20232023-07-01 00:00:00 UTC2023-08-01 00:00:00 UTC101
Aug 20232023-08-01 00:00:00 UTC2023-09-01 00:00:00 UTC000
Sep 20232023-09-01 00:00:00 UTC2023-10-01 00:00:00 UTC000
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 UTC000
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 UTC000
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 UTC110

What Hacker News says

2 sources
This thing looks interesting. But I don't get it. What's exactly novel about all this? I see an untyped(!) DSL to model actor supervisor hierarchies, including a protocol which allows the actors to access some shared mutable state. But else? (Maybe besides some NIH and "rewrite the world" allures?) From a systems architecture point of view this looks actually very good, but all the details are more or less standard stuff found in industry products since quite some time. Don't get me wrong, the engineering behind this systems architecture is quite impressive! But it's engineering, not research to me. The other thing is, all hard problems, there where the "fun" starts, seem actually unsolved. Form the end of the dissertation defense slides: Future Work Enhancements to the formal models - types; names; grouping & relaying; formal
Read the rest
properties System model - performance; tool support; generic protocols; process management; stdio; contracts; security; persistence; polyglot Distributed systems - unpredictable latency & scheduling; message loss; subnets I'm not sure this is actually easy to solve. The basic idea here seems to be that actors coordinate with the help of shared mutable state (the "dataspace"). At this point you're actually back to square one as synchronizing shared state is the core problem with distributed, concurrent systems… Given that, and the fact that this whole thingy is untyped makes me skeptical. Not even the std. ingredients like type-state, session types, behavioral types, or the like seem to get used. I also don't see linear types here, which go very well with session types / behavioral types, and can help making typing message passing easier. Also that this approach would be completely network transparent, as I see it, seems like a design flaw. One needs control over the various effects that can occur! Otherwise the points form "distributed systems future work" can't be solved, imho. And form the practical point of view: There is no Akka / Pekko based Scala implementation? I'm quite surprised, to be honest. Akka / Pekko is the actor runtime, and Scala is famous for it's eDSL features; besides of course its type-system, which makes things like Libretto possible, which seems related here: https://github.com/TomasMikula/libretto Syndicate-lang looks OTOH more like the usual callback-hell. But like I've said, I don't get this whole thingy really. I've just clicked through some parts of the web-sites. Most likely I'm just overlooking the elephant in the room. So would be glad to learn more! (BTW: Very nice web-site design on all the projects. Especially nice typography. Really enjoyed this part while clicking through this stuff.)
In Synit – A Reactive Operating System

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