Jon Pretty (@propensive) / X

Jon Pretty

17.9K posts

Jon Pretty

@propensive

Scala 3 developer

Germany

Joined July 2010

@propensive

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Jon Pretty
@propensive
Sep 11, 2025
I am very happy to announce that will be speaking at Scala.io in Paris on 17 October! This will be my first conference talk since 2019, and I'm going to try to make it the best ever! I will introduce soundness.dev to the world: a tour de force of all the
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Jon Pretty
@propensive
Apr 26, 2024
A Statement I am a Scala developer and speaker who was cancelled three years ago. Yesterday I attended the High Court in London to hear an apology from several prominent members of the Scala community for making untrue claims about me on 27 April 2021. I sued them for libel, and
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Jon Pretty
@propensive
Sep 6, 2019
As a consequence of the revocation of @jdegoes's talk at @scalaexchange, I have decided to decline the offer to speak there, and will not involve myself with any @skillsmatter events until there's a change to the way decisions like this are made. /1
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Jon Pretty
@propensive
Oct 29, 2020
We're very pleased and excited to reveal scala.zone to the world today! ScalaZONE is a free online learning platform for Scala 3, with lessons, videos and exercises for everyone. We launch today with 20 beginner lessons, but with over 100 more scheduled weekly!
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Jon Pretty
@propensive
Aug 1, 2025
I was cancelled in 2021 for something I didn't do. The impact this had on my life was devastating, but I've never had the courage to talk about it before. This is my story of the misery that cancellation brought to my career, my social life and my health. ↓↓↓
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Jon Pretty
@propensive
Jan 29, 2020
Does anyone else seem to spend 50x more time deleting characters like ", } and ) which their IDE inserts automatically, than they save not having to type them on the fewer occasions they get inserted in the right place? Or is it just me?
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Jon Pretty
@propensive
Dec 1, 2018
If we will all need to refactor our code for Scala 3 once implicits are deprecated, I only hope we can do this automatically...with a Witness Relocation Program.
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Jon Pretty
@propensive
Feb 13, 2018
I have wanted this since I started writing Scala, and today I finally implemented it: compile-time-checked regular expressions. With capturing group extraction, directly from patterns. Ready to try right now! "com.propensive" %% "kaleidoscope" % "0.1.0" github.com/propensive/kal…
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Jon Pretty
@propensive
Oct 18, 2017
My closing remarks at Scala World discussed division, complexity and confidence in the Scala community. My new blog: pretty.direct
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Jon Pretty
@propensive
Mar 19, 2018
Programming should be accessible to all software developers, regardless of physical disability. Read about what the Scala Center and its sponsors are doing to help make the Scala compiler easier to use for blind and partially-sighted developers:
scala-lang.org
Accessibility of the Scala Compiler
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Jon Pretty
@propensive
Oct 1, 2020
We're proud to be part of ScalaZONE: a new initiative with @VirtusLab to support education for the whole Scala community; a brand new and comprehensive learning platform for Scala 3, completely open and free forever, launching in October. Watch our intro! youtube.com/watch?v=FvYS8r…
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Jon Pretty
@propensive
Sep 23, 2016
Congratulations, @tpolecat: you are now a fully-fledged meme.
GIF
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Jon Pretty
@propensive
Dec 5, 2017
For three years, Anna Modosiani has wonderfully painted each and every Scala World speaker from Aaron to Zainab (and some who didn't quite make it)! If you would like her to paint *you*, please DM me and I can share her contact details. Each portrait is $75.
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Jon Pretty
@propensive
Nov 16, 2018
I finally bit the bullet and open-sourced Fury. You probably won't have any luck building it yet, and it's undoubtedly riddled with bugs, but it's now yours. Please don't look.
GitHub - propensive/fury: A build tool for Scala
From github.com
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