Optics in Funx: same thing, different representations. That’s an Iso. Includes a Livebook www.joekoski.com/blog/2026/01... #elixirlang #livebook #funx

My book is #1 on Amazon! Proving once again that you can be #1 in anything, as long as you control the denominator. a.co/d/dPiWKRE

New speakers: Lorena Miles, @hayleigh.dev & @jkwa.bsky.social join Code BEAM Lite Vancouver! More announcements coming. Join waiting list for exclusive pricing. codebeamvancouver.com#speakers

More optics in Funx: when you need multiple foci, use a traversal. Includes a Livebook www.joekoski.com/blog/2026/01... #elixirlang #livebook #funx

Insight: Top Ten 2025 Titles at pragprog.com #6 Advanced Functional Programming with Elixir by Joseph Koski @jkwa.bsky.social pragprog.com/titles/... Use code INSIGHT to save 40% off this title (and almost everything else) at pragprog.com

Funx: Reorganizing Eq and Ord www.joekoski.com/blog/2025/12... #elixirlang

Funx Optics: Declare your order. www.joekoski.com/blog/2025/12... #elixirlang

My book up on Amazon 🎉 About 900 people have already purchased it directly from the Pragmatic Bookshelf. If you’re one of them, I’d really appreciate a review. Even a quick sentence or two makes a huge difference. a.co/d/bWoZwVc

More optics in Funx: name your shareable boundaries with prisms. Includes a Livebook. www.joekoski.com/blog/2025/12... #elixirlang

Couldn't fit optics in my book, but I can build them into Funx. Here's why lawful lenses matter (even in Elixir): www.joekoski.com/blog/2025/12... #elixirlang

New blog post: After building out the Either DSL, I realized Funx needed a context-aware tap. www.joekoski.com/blog/2025/12... #elixirlang

New post in my Ash Framework series. This time I’m lifting a few of Ash’s DSL ideas (or stealing them outright) to build an Either DSL in Funx. www.joekoski.com/blog/2025/12... #elixirlang @pragprog.com

A new post in my series on the Ash Framework. This one looks at calculations and includes functional programming strategies for managing uncertainty. www.joekoski.com/blog/2025/11... #elixirlang @pragprog.com

When the work of our authors intersects, it's amazing. Such a privilege to provide a platform for all these talented, passionate humans. And, their books are included in our Black Friday, 50% off sale!

A new post in my series on the Ash Framework. This one explores the underlying mechanics of Ash validation and where Funx can help when checks need more structure or concurrency. www.joekoski.com/blog/2025/11... #elixirlang @pragprog.com

Another in my series on the Ash Framework. Understanding actions from a functional programming perspective. www.joekoski.com/blog/2025/11... #elixirlang

Yet another in my series on the Ash Framework. I wanted to explore what it’s like to bring Ash into an existing project. www.joekoski.com/blog/2025/11... #elixirlang

Adding to my series on the Ash Framework book. Exploring how Ash works with Ecto and taking the opportunity to try a promising new library called Electric. www.joekoski.com/blog/2025/10... #elixirlang @pragprog.com

Beta Update Advanced Functional Programming with Elixir by @jkwa.bsky.social Model Behavior, Manage Complexity, and Maximize Maintainability pragprog.com/titles/... B5.0 Release Notes: * Production complete. On to layout & print. (Already purchased? Check your email for a download link.)

Adding to my series on the Ash Framework book. Taking a closer look at messy authorization. www.joekoski.com/blog/2025/10... #elixirlang @pragprog.com

Back from vacation and I thought I'd add to my series on the Ash Framework book. Why does authorization logic get messy? www.joekoski.com/blog/2025/10... #elixirlang @pragprog.com

Alongside the book, you’ll find a production-ready library that implements these abstractions—fully tested, well documented, and ready to use. Advanced Functional Programming in Elixir by @jkwa.bsky.social pragprog.com/titles/... 40% off through the weekend with code Pragpicks

Next in my series on the Ash Framework book. What makes Ash different? www.joekoski.com/blog/2025/10... #elixirlang @pragprog.com

I learn best by writing, so I wrote up some higher-level notes on Ash from the Ash Framework book. I thought others might find it useful: www.joekoski.com/blog/2025/10... #elixirlang @pragprog.com

I walked away from ElixirConf thinking it was time to take a serious look at Ash. I don’t have time to wander around, so I picked up the Ash Framework book. Halfway through, I get it. pragprog.com/titles/ldash... #elixirlang @pragprog.com

An early reader had a suggestion. Connect functional programming patterns to the libraries Elixir devs already use. It’s a good idea, but I didn’t have space in the book. www.joekoski.com/blog/2025/09... #elixirlang #funx #PragProg

One package. One update. A worm crawling through the BEAM ecosystem. A dark “what if” — and how we can stop it before it’s real. erlef.org/blog/securit... #erlang #elixirlang

Advanced Functional Programming with Elixir just climbed back to #1 on the @PragProg best seller list! pragprog.com/best_sellers/ #afpelixir #elixirlang

Want to tinker? Sharing to see what folks think. www.joekoski.com/blog/2025/09...

PragProg is running a 48-hour flash sale — 45% off all books with code flashsale That includes my book Advanced Functional Programming with Elixir Sale runs Sept 18–20, 9am CT Grab it here: pragprog.com #pragprog

Elixir Radar issue 484is out! 📣 You can read it here: buff.ly/vWcu6fa This issue comes with content from @peerstr.bsky.social @jkwa.bsky.social @mikezornek.com @josevalim.bsky.social , Mike Hostetler and Sven Van Caekenberghe .Thank you! #ElixirLang

Another deleted scene from my book: There are many ways to solve equality: duck typing, injection, protocol dispatch. Here's why Funx uses the one it does: www.joekoski.com/blog/2025/09... #elixirlang #funx #AFPElixir

I 💜 this passage from @jkwa.bsky.social buff.ly/xIVq6gW "... understanding doesn’t parallelize, and complexity doesn’t distribute. Each new contributor must climb the same tangled mess... even more time is spent coordinating, clarifying, and patching over mismatches in mental models." #elixirlang

Funx now has Livebooks. I considered a plugin, but thought this might be a good job for an LLM. This short post covers my strategy: www.joekoski.com/blog/2025/09... #elixirlang #funx

Most personal blogs are in the low hundreds of unique visitors per month. Mine was too. This month I passed a milestone. #elixirlang

I just finished putting together interactive Livebook notebooks for every chapter of Advanced Functional Programming with Elixir. You can now run all the examples in your browser. Or like me, spin them up locally with Docker: www.joekoski.com/blog/2025/09... #elixirlang hashtag#AFPElixir

Just checked in to see if Funx had hit 80 downloads. Any ideas on what happened? www.joekoski.com/blog/2025/09... #elixirlang #funx #AFPElixir

Some comments on an earlier post had me thinking about polymorphic equality in Elixir, and how == can fall short. www.joekoski.com/blog/2025/08... #elixirlang #AFPElixir

Just got The BEAM Book by Erik Stenman in the mail. Time to go spelunking in the BEAM! #elixirlang #erlang #beam #AFPElixir

Follow-up post on polymorphism in Elixir. This one looks at how structs help avoid pitfalls from other languages. www.joekoski.com/blog/2025/08... #elixirlang #AFPElixir

I wrote this post about polymorphism in Elixir. Details I wish I had known five years ago. www.joekoski.com/blog/2025/08... #elixirlang #AFPElixir

Why is learning FP so hard? I wrote a short post on my blog about this a couple of weeks back. www.joekoski.com/blog/2025/08... #Elixir #LearnFP

I can already tell I'm going to be spending most of my labor day reading through the beta edition of @jkwa.bsky.social's @pragprog.com book: pragprog.com/titles/jkeli... #ElixirLang #FunctionalProgramming

Celebrating Advanced Functional Programming with Elixir by Joseph Koski now in beta! 🔗 Read more: bit.ly/3V5AQBZ 📘 ebook: pragprog.com/titles/... #Elixir #functionalprogramming #MyElixirStatus #WeBEAMTogether #programming #pragprog