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Joseph Koski @jkwa.bsky.social · 2d

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

#elixirlang @pragprog.com

Ash Framework: The Coordination Problem

Not organization but coordination.

www.joekoski.com

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Joseph Koski @jkwa.bsky.social · 6d

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

Ash Framework: My Misconceptions

It’s all about the domain.

www.joekoski.com

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Joseph Koski @jkwa.bsky.social · 12d

Hmm... I like the Ash thing, but perhaps it could be more like Haskell?

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Joseph Koski @jkwa.bsky.social · 13d

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

Ash Framework

Explore the power of Ash Framework by modeling and building the domain for a real-world web application.

pragprog.com

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Joseph Koski @jkwa.bsky.social · 14d

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

What’s an Effect?

How do we handle side effects in a pure functional system?

www.joekoski.com

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Reposted by Joseph Koski

Jonatan Männchen @maennchen.dev · 15d

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

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Joseph Koski @jkwa.bsky.social · 16d

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

#afpelixir #elixirlang

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Joseph Koski @jkwa.bsky.social · 21d

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

Can an LLM Tutor?

“I’m not even sure what’s real anymore.” —The Matrix (1999)

www.joekoski.com

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Joseph Koski @jkwa.bsky.social · 21d

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

Pragmatic Bookshelf: By Developers, For Developers

We improve the lives of professional developers. We create timely, practical books on classic and cutting-edge topics to help you learn and practice your craft, and accelerate your career. Come learn ...

pragprog.com

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Reposted by Joseph Koski

Elixir Radar @elixir-radar.com · 22d

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

Elixir Radar 484

buff.ly

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Joseph Koski @jkwa.bsky.social · 22d

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

Polymorphism and Behavior Injection

When are two things the same?

www.joekoski.com

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Reposted by Joseph Koski

Nicholas Henry @nicholasjhenry.github.io · 23d

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

Advanced Functional Programming with Elixir

Use advanced functional programming principles, practical domain-driven design techniques, and production-ready Elixir code to build scalable, complex systems from simple, reusable components.

pragprog.com

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Joseph Koski @jkwa.bsky.social · 24d

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

Generate Livebooks with an LLM

So many loops…

www.joekoski.com

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Joseph Koski @jkwa.bsky.social · 27d

...or get a friend who badgers you to post things on social media. That works as well.

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Joseph Koski @jkwa.bsky.social · 27d

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

#elixirlang

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Joseph Koski @jkwa.bsky.social · 29d

Thanks! I reposted with he right one

Joseph Koski @jkwa.bsky.social · 29d

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

Livebook Examples from Advanced Functional Programming with Elixir

It feels a bit impolite to ask readers to download code and type mix commands just to run the examples. We have better tools now.

www.joekoski.com

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Joseph Koski @jkwa.bsky.social · 29d

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

What is going on?

“They found me. I don’t know how, but they found me.” — Dr. Emmett Brown

www.joekoski.com

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Joseph Koski @jkwa.bsky.social · Sep 9

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

What’s the point of a polymorphic eq?

Why not keep equality inside the module where it belongs?

www.joekoski.com

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Joseph Koski @jkwa.bsky.social · Sep 9

Just got The BEAM Book by Erik Stenman in the mail.
Time to go spelunking in the BEAM!

#elixirlang #erlang #beam #AFPElixir

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Joseph Koski @jkwa.bsky.social · Sep 7

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

Polymorphism and Structs in Elixir

Polymorphism has always relied on tags. Elixir’s structs make them safer.

www.joekoski.com

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Joseph Koski @jkwa.bsky.social · Sep 4

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

Polymorphism in Elixir

This post walks through the basics of protocols in Elixir. It’s the information I wish I knew five years ago.

www.joekoski.com

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Joseph Koski @jkwa.bsky.social · Sep 2

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

Why Is This So Hard?

A blog about software development, data science, and other things I find interesting.

www.joekoski.com

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Reposted by Joseph Koski

{:ok, Noah} @nezteb.net · Sep 1

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

Advanced Functional Programming with Elixir

Use advanced functional programming principles, practical domain-driven design techniques, and production-ready Elixir code to build scalable, complex systems from simple, reusable components.

pragprog.com

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Reposted by Joseph Koski

Margaret Eldridge @margeditor.bsky.social · Aug 20

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

Book cover for Advanced Functional Programming with Elixir by Joseph Koski, showing a world map with glowing blue paths, arrows, and markers

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