Hi Effecters!

Welcome back to This Week In Effect (TWIE) – your weekly update of the latest developments in the Effect community and ecosystem.

Effect is a powerful TypeScript library that helps developers create complex, synchronous, and asynchronous programs. One key feature that sets Effect apart is how it leverages structured concurrency to provide features such as async cancellation and safe resource management, making it easier to build robust, scalable, and efficient programs.

Get started with Effect with our quick-start guide and documentation below:

• Effect quick-start guide
• Effect docs

Recent major updates:

• Effect is API stable with the Effect 3.0 release.
• Effect 3.9 has been released.
• The Effect community on Discord reached 3680+ members!

#Technology

Here are all the technical changes from this week.

#Effect Core

• Add option to .releaseLock a ReadableStream on finalization (Feature, next-minor)
• Merge Schema into Effect (Feature, next-minor)
• Schema.equivalence: fix discriminated tuples (Bug Fix, next-minor)
• Porting of #3792 (Feature, next-minor)

#Effect Platform

• Remove Scope requirement from NodeHttpServer.makeHandler (Improvement)
• Ensure cors middleware also affects error responses (Bug Fix)
• Fix HttpMiddleware circular import (Bug Fix)

#Effect Schema

• Equivalence: Fixed a bug related to discriminated tuples (Bug Fix)
• Resolve parse error when using pick with union of class schemas (Bug Fix)

#Effect Vitest

• Vitest README: add Logging section (Documentation Update)

#General Chores

• Dx: add watch task to expose all compile errors to vscode, including not open files.

#Community highlights

• The San Francisco Effect Meetup is approaching fast on Oct 21st, and we announced our final speaker: Dillon Mulroy, Software Engineer at Vercel.

• Also, we have a sneak peek of the upcoming Elliot Dauber speech: Lessons Learning Effect.

• The 3rd Effect Paris Meetup is now scheduled on November 5th and will be hosted by Spiko. There's still time to submit a proposal if you'd like to give a talk. As a reminder, the meetup will be in French.

• Congrats to Aiden Bai and the Million team for rewriting their installer with Effect.

• Sandro Maglione published a quick guide on how to use effect/rpc to create a server and derive a client from it.

• Dillon Mulroy live-streamed five new episodes about Building with EffectTS, Svelte 5, and Postgres on his Twitch channel.

• You don't want to miss Lucas Barake's latest video explaining how Effect helps developers simplify their codebase.

• Marcelo Bairros, dives deep into Effect in the following video emphasizing its value for TypeScript developers looking to optimize their workflows, handle errors more effectively, and more.

• Effect is mentioned in a recent video on the Web Dev Simplified YouTube channel, as an advanced library that offers built-in error handling, highlighting its potential for complex applications.

#Effect content updates

• Tim Smart went live on Thursday with a new episode of Reimagining Contentlayer with Effect, where he worked on both HttpApi & ContentLayer.

• The second episode of Mattia Manzati's series on Building a small warehouse app with Effect aired on Thursday.

• The fifth and the sixth parts of Reimagining Contentlayer with Effect have already been published on the Effect YouTube Channel.

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#Closing notes

That's all for this week. Thank you for being a vital part of our community. Your feedback is highly valued as we fine-tune this format. Feel free to share your thoughts, and we'll do our best to tailor it to the needs of our community.

Effect Community Team