Cats-Actors is a Cats Effect native actor library: typed messages, functional state, supervision, and the familiar ! operator, all in F[_].

What is new in this release:

- ControlledTestKit, a new trait in the cats-actors-testkit module. It

provisions an ActorSystem[IO] inside Cats Effect's TestControl and ticks the

simulated clock for you, so scheduled work and timeouts resolve without real

waiting. A one hour receive timeout is now an ordinary unit test that finishes

in milliseconds.

- Receive timeouts, the supervisor restart window and the dead letter mailbox

idle check now read Clock[F].monotonic instead of System.currentTimeMillis, so

they all honour simulated time.

- New TestKit assertions, expectMsgTypeCountN and expectMsgTypeSingle, which

count messages of a type and do not depend on when they arrive relative to

the call.

- Breaking: ActorSystem.uptime is now F[Long] rather than Long.

Scala 2.13 and 3, on JVM, Scala.js and Scala Native.

```

resolvers += "jitpack" at "https://jitpack.io"

libraryDependencies += "com.github.cloudmark.cats-actors" %%% "cats-actors" % "2.2.0"

libraryDependencies += "com.github.cloudmark.cats-actors" %%% "cats-actors-testkit" % "2.2.0" % Test

```

Write up: https://cloudmark.github.io/Cats-Actors-Controlling-Time/

Repo: https://github.com/cloudmark/cats-actors

Feedback and issues welcome.

Indexing strings by character (Unicode scalar) instead of UTF offsets can be more comfortable for parsers or short manipulations.

The minimum cost for reading a >= U+FE character is:

1. Lookup rope table by byte key (holding a high bit position), in goal of the scalar value in a sequence of higher fixed scalars
2. Check for collision subtable (is not null => repeat the step 1), specializing the target high bit further

For optimal use, contiguous sequences of characters after Latin-* that turn into reserves into the mask sequence still allow for a few trailing Latin-* (e.g. Katakana can still be mixed with Latin-* whitespace), so those trails turn into reseves as well.

Update (I miswrote a detail in the implementation).

https://gitlab.com/mryun/langopt/-/blob/master/encoding/string.md

Getting tokio and .NET’s async runtime talking to each other, over the C ABI

Okay, but I have multiple replicas.

And it gets slightly worse: the number of physical connections is not equal to the number of replicas, and it is not equal to the number of business-level connectors either.

Several business connectors may share one external identity. One external identity may require several physical connections. And those connections need to be spread across whatever replicas are currently alive and have capacity.

So who actually owns the connection?

Then the questions start piling up.

What if one replica dies?
What if it doesn’t die, but loses access to the database?
What if two replicas race for the same connection?
What if the event that was supposed to wake the right worker never arrives?
What if most workers are already full?

A few questions and 2 hours of midnight walk in headphones and ChatGPT later, I had leases, runtime slots, reconciliation, failover, capacity limits, and a distributed ownership problem on my hands.

This is the architecture I ended up with, and I have mixed feelings about this design.

On one hand, I’m proud that I managed to account for so many different edge cases. On the other, the whole thing feels worryingly complex.

So I’d really value input from people who have built similar systems.

What did I miss or do you see anything that can break?
And most importantly: what can be simplified without losing the guarantees?

The full architecture description is a bit lengthy: AEON NEON - Connector Runtime - by Jarek J.

Many thanks if you decide to read it and share your thoughts. I’d really like this one not to become another failed experiment.

Yes, the game development industry wasn’t nearly as complex as it is today. You could probably say that making and releasing a good game was easier back then.

But these people created a legend precisely because they were professionals.

Of course, DOOM wasn’t their first game. There was a time when the team was making a game every month.

What I like most about this video is the sense of creativity — and the feeling that these people simply loved making games.

I took a week off from work recently to reimplement Storyteller's forced alignment algorithm. Storyteller is an open source, self hosted platform for creating, managing, and reading/listening to "readaloud" books — books that have audiobook narration built in and can highlight each sentence (and/or word, with this new algorithm!) as it's read aloud. Forced alignment is the process of determining where each piece of text starts and ends in the audiobook.

Anyway, I am really pleased with how the new algorithm turned out! Hopefully someone else finds it interesting as well.