Ole Vedel Villumsen
@olevv.bsky.social
Any pronouns (most use he/him).
Software developer (Java), father of two teenagers, amateur musician.
Concerned about the climate and man-made climate change.
Software developer (Java), father of two teenagers, amateur musician.
Concerned about the climate and man-made climate change.
I admit that before coming to #Jfokus2026 I thought virtual threads in #Java sounded like a good idea, but it was unclear what I wanted to use them for. After the talks and lab in the conference I have a very clear picture.
February 4, 2026 at 12:03 PM
I admit that before coming to #Jfokus2026 I thought virtual threads in #Java sounded like a good idea, but it was unclear what I wanted to use them for. After the talks and lab in the conference I have a very clear picture.
At #Jfokus @josepaumard.bsky.social gave the inspiring hands-on lab on structured concurrency and virtual threads. The learning material is good, so I am looking forward to digging still deeper after the conference. #Java
February 3, 2026 at 11:35 AM
At #Jfokus @josepaumard.bsky.social gave the inspiring hands-on lab on structured concurrency and virtual threads. The learning material is good, so I am looking forward to digging still deeper after the conference. #Java
The first day of #jfokus, the hands-on day, so where you learn and end up tired. @timtebeek.github.io and @rickossendrijver.bsky.social presented "Break your testing habits", advocating #AssertJ, but also a scary eye-opener how much many of us still stick to obsolete habits we learned with #JUnit 3.
February 3, 2026 at 11:30 AM
The first day of #jfokus, the hands-on day, so where you learn and end up tired. @timtebeek.github.io and @rickossendrijver.bsky.social presented "Break your testing habits", advocating #AssertJ, but also a scary eye-opener how much many of us still stick to obsolete habits we learned with #JUnit 3.
Reposted by Ole Vedel Villumsen
NEW RESEARCH: Climate change on track to slash global crop yields by 24% before 2100.
Like, within the lifespan of your kids.
Also: adaptation and new farmland can’t offset this loss. Sorry, AI can’t fix this.
agupdate.com/agriview/mar...
Like, within the lifespan of your kids.
Also: adaptation and new farmland can’t offset this loss. Sorry, AI can’t fix this.
agupdate.com/agriview/mar...
Climate change will devastate crop yields
A sweeping new analysis finds that warming global temperatures will dampen the world’s capacity to produce food from most staple crops, even after accounting for economic development and adaptation by
agupdate.com
January 27, 2026 at 11:05 PM
NEW RESEARCH: Climate change on track to slash global crop yields by 24% before 2100.
Like, within the lifespan of your kids.
Also: adaptation and new farmland can’t offset this loss. Sorry, AI can’t fix this.
agupdate.com/agriview/mar...
Like, within the lifespan of your kids.
Also: adaptation and new farmland can’t offset this loss. Sorry, AI can’t fix this.
agupdate.com/agriview/mar...
Of the people praising IntelliJ IDEA (for instance of the occasion of its 25th birthday), how many have been given a license they don’t pay for? How does this contribute to the amount of praise? And how many of them mention the gift along with the praise (I haven’t seen any yet)?
January 19, 2026 at 4:03 PM
Of the people praising IntelliJ IDEA (for instance of the occasion of its 25th birthday), how many have been given a license they don’t pay for? How does this contribute to the amount of praise? And how many of them mention the gift along with the praise (I haven’t seen any yet)?
Reposted by Ole Vedel Villumsen
These are the icy mountains of Pluto. It took 9 years to get these magnificent images… and 4.8 billion kilometers.
January 18, 2026 at 7:39 PM
These are the icy mountains of Pluto. It took 9 years to get these magnificent images… and 4.8 billion kilometers.
Reposted by Ole Vedel Villumsen
A thread 🧵 of _terrible_ design decisions for the internal APIs of the two Italian high speed train operators, Italo and Trenitalia.
Hardcoded passwords, terrible translations, spelling mistakes, xml in json (but utf8 encoded and transmitted as an array of numbers), it's all here. Enjoy!
Hardcoded passwords, terrible translations, spelling mistakes, xml in json (but utf8 encoded and transmitted as an array of numbers), it's all here. Enjoy!
December 28, 2025 at 10:08 PM
A thread 🧵 of _terrible_ design decisions for the internal APIs of the two Italian high speed train operators, Italo and Trenitalia.
Hardcoded passwords, terrible translations, spelling mistakes, xml in json (but utf8 encoded and transmitted as an array of numbers), it's all here. Enjoy!
Hardcoded passwords, terrible translations, spelling mistakes, xml in json (but utf8 encoded and transmitted as an array of numbers), it's all here. Enjoy!
Reposted by Ole Vedel Villumsen
If you need to get up to speed with null safety in #Java with #JSpecify and @manu.sridharan.net's #NullAway, watch @seb.deleuze.fr's excellent presentation from @springio.net 2025.
www.youtube.com/watch?v=5Lbx...
www.youtube.com/watch?v=5Lbx...
Null Safety in Java with JSpecify and NullAway by Sébastien Deleuze @ Spring I/O 2025
YouTube video by Spring I/O
www.youtube.com
December 26, 2025 at 6:20 AM
If you need to get up to speed with null safety in #Java with #JSpecify and @manu.sridharan.net's #NullAway, watch @seb.deleuze.fr's excellent presentation from @springio.net 2025.
www.youtube.com/watch?v=5Lbx...
www.youtube.com/watch?v=5Lbx...
A colleague objected to using the assert keyword in production Java code. He thinks it will only ever be checked during running unit tests and prefers to have the assertion in the test. 1/2 #Java
November 17, 2025 at 10:42 AM
A colleague objected to using the assert keyword in production Java code. He thinks it will only ever be checked during running unit tests and prefers to have the assertion in the test. 1/2 #Java
My teenager and a friend asked who invented, owns and develops Java. I gave them the very short story from memory.
Java was developed by a group lead by James Gosling and was launched by a company named Sun Microsystems Inc. (1/4) #Java #techhistory
Java was developed by a group lead by James Gosling and was launched by a company named Sun Microsystems Inc. (1/4) #Java #techhistory
November 13, 2025 at 2:11 PM
My teenager and a friend asked who invented, owns and develops Java. I gave them the very short story from memory.
Java was developed by a group lead by James Gosling and was launched by a company named Sun Microsystems Inc. (1/4) #Java #techhistory
Java was developed by a group lead by James Gosling and was launched by a company named Sun Microsystems Inc. (1/4) #Java #techhistory
I have secured my ticket for Jfokus, Stockholm February 2–4. Looking forward like a little kid.
October 6, 2025 at 5:03 AM
I have secured my ticket for Jfokus, Stockholm February 2–4. Looking forward like a little kid.
Reposted by Ole Vedel Villumsen
#SaveSpeech
Opposition to Chat Control within Denmark is growing. If you are a Danish citizen, please sign this petition:
www.borgerforslag.dk/se-og-stoet-...
At 50k sigs, it is submitted to the parliament and undergoes the standard leg process, including potential debates, review, and vote.
Opposition to Chat Control within Denmark is growing. If you are a Danish citizen, please sign this petition:
www.borgerforslag.dk/se-og-stoet-...
At 50k sigs, it is submitted to the parliament and undergoes the standard leg process, including potential debates, review, and vote.
Nej til EU’s “Masseovervågning” beskyt vores privatliv, digitale sikkerhed og ytringsfrihed.
Vi beder Danmark om at stemme nej til EU’s “Chatkontrol” en lov, der pålægger masseovervågning af alle borgere ved at scanne private beskeder, e-mails
www.borgerforslag.dk
September 21, 2025 at 6:22 PM
#SaveSpeech
Opposition to Chat Control within Denmark is growing. If you are a Danish citizen, please sign this petition:
www.borgerforslag.dk/se-og-stoet-...
At 50k sigs, it is submitted to the parliament and undergoes the standard leg process, including potential debates, review, and vote.
Opposition to Chat Control within Denmark is growing. If you are a Danish citizen, please sign this petition:
www.borgerforslag.dk/se-og-stoet-...
At 50k sigs, it is submitted to the parliament and undergoes the standard leg process, including potential debates, review, and vote.
Reposted by Ole Vedel Villumsen
errorprone.info/docs/time for programmers, and people who like to know things. By @kevinb9n.bsky.social . Thorough, knowledgeable, a sound read for all programmers, entertaining, practical. Recommended.
How to Think About Time
errorprone.info
August 10, 2025 at 8:28 AM
errorprone.info/docs/time for programmers, and people who like to know things. By @kevinb9n.bsky.social . Thorough, knowledgeable, a sound read for all programmers, entertaining, practical. Recommended.
Reposted by Ole Vedel Villumsen
First JDK 25 Release Candidate: mail.openjdk.org/pipermail/jd...
Downloads: jdk.java.net/25/
#JDK25 #Java25 #OpenJDK #TestItNow
Downloads: jdk.java.net/25/
#JDK25 #Java25 #OpenJDK #TestItNow
August 9, 2025 at 12:12 AM
First JDK 25 Release Candidate: mail.openjdk.org/pipermail/jd...
Downloads: jdk.java.net/25/
#JDK25 #Java25 #OpenJDK #TestItNow
Downloads: jdk.java.net/25/
#JDK25 #Java25 #OpenJDK #TestItNow
Reposted by Ole Vedel Villumsen
When they don't have a case, they lie.
HOME OFFICE DISINFORMATION CAMPAIGN OVER PALESTINE ACTION BAN EXPOSED
@declassifiedUK has revealed that Home Office insinuations that Palestine Action supports violence and receives funding from Iran were refuted by its own internal assessments.
In full: www.declassifieduk.org/revealed-how...
@declassifiedUK has revealed that Home Office insinuations that Palestine Action supports violence and receives funding from Iran were refuted by its own internal assessments.
In full: www.declassifieduk.org/revealed-how...
Revealed: How Palestine Action was banned
Exclusive: Documents seen by Declassified reveal serious concerns within the UK government and MI5 about proscribing Palestine Action.
www.declassifieduk.org
July 29, 2025 at 6:30 AM
When they don't have a case, they lie.
My friend @arvind-avinash.bsky.social invited me and my girl friend to his house when we were in London last week. We had a good and inspiring time together. (I originally know Arvind from Stack Overflow.)
July 17, 2025 at 9:14 PM
My friend @arvind-avinash.bsky.social invited me and my girl friend to his house when we were in London last week. We had a good and inspiring time together. (I originally know Arvind from Stack Overflow.)
Reposted by Ole Vedel Villumsen
Thanks to Matthias van de Meent, I've deleted my toot on #PostgreSQL 18 since after verification, it claimed "unverified" capabilities.
Matthias van de Meent (@mmeent_pg@fosstodon.org)
@frankel@mastodon.top Hey, I just want to warn you - the first headline of the article, just above the cutoff for paid accounts "1. Parallel COPY from file to table" sounds like someone looking for cl...
fosstodon.org
June 27, 2025 at 5:08 AM
Thanks to Matthias van de Meent, I've deleted my toot on #PostgreSQL 18 since after verification, it claimed "unverified" capabilities.
Not sure exactly how it fits, but I’ll take it. #Java30WithIntelliJIDEA plugins.jetbrains.com/plugin/27445...
May 31, 2025 at 5:12 AM
Not sure exactly how it fits, but I’ll take it. #Java30WithIntelliJIDEA plugins.jetbrains.com/plugin/27445...
They say my official age of retirement will be in 8 months. I couldn’t care less. I have an interesting and lovely software development job, and i am not letting go of it.
May 26, 2025 at 5:02 PM
They say my official age of retirement will be in 8 months. I couldn’t care less. I have an interesting and lovely software development job, and i am not letting go of it.
Find your national ID number (for example your passport number) and sign this petition to free 11 Peruvian environmentalists fighting for clean air and indigenous people.
docs.google.com/forms/d/e/1F...
docs.google.com/forms/d/e/1F...
Alto a la criminalización de las personas defensoras en Cotabambas
Español:
Las personas y organizaciones firmantes denunciamos la injusta criminalización de 11 defensores ambientales y de derechos humanos provenientes de comunidades ubicadas en la provincia de Cota...
docs.google.com
March 27, 2025 at 12:20 PM
Find your national ID number (for example your passport number) and sign this petition to free 11 Peruvian environmentalists fighting for clean air and indigenous people.
docs.google.com/forms/d/e/1F...
docs.google.com/forms/d/e/1F...
“Dad, I want to run a Minecraft server for my sibling and a friend. Have I got Java on my computer? (My home field.) How do I configure port forwarding in the router? (Not my home field, also not hard.) Why don’t the Minecraft mods I got work? (Fortunately a friend helped with that.)”
March 25, 2025 at 8:24 AM
“Dad, I want to run a Minecraft server for my sibling and a friend. Have I got Java on my computer? (My home field.) How do I configure port forwarding in the router? (Not my home field, also not hard.) Why don’t the Minecraft mods I got work? (Fortunately a friend helped with that.)”
On March 31 the Danish Broadcasting Corporation archive at Royal Danish Library will open to the public. As software developer I am preserving broadcast radio and TV and in this way will contribute to the archive. (Press release in Danish: kum.dk/aktuelt/nyhe...)
Millioner af DR-udsendelser på vej til danskerne
Kulturministeriets væsentligste opgaver består i ministerrådgivning og lovgivningsmæssige initiativer. Kulturministeriet består af Kulturministeriets departement, en styrelse og ca. 20 statsinstitutio...
kum.dk
March 21, 2025 at 9:01 AM
On March 31 the Danish Broadcasting Corporation archive at Royal Danish Library will open to the public. As software developer I am preserving broadcast radio and TV and in this way will contribute to the archive. (Press release in Danish: kum.dk/aktuelt/nyhe...)
Crazy: playing the piano during work hours. The Århus branch of Royal Danish Library invites users, employees, everyone interested, to join us singing two songs every Thursday at 9:30 AM Danish time. We’re three employees taking turns accompanying. How I enjoy it.
February 25, 2025 at 1:00 PM
Crazy: playing the piano during work hours. The Århus branch of Royal Danish Library invites users, employees, everyone interested, to join us singing two songs every Thursday at 9:30 AM Danish time. We’re three employees taking turns accompanying. How I enjoy it.
My teenager draws …
@spearmintdoesart27.bsky.social oc Barbage
hes a cutie and i wanted to draw him for ages but never got around to it and so i got carried away
i just wanted to make a doodle....
hes a cutie and i wanted to draw him for ages but never got around to it and so i got carried away
i just wanted to make a doodle....
February 22, 2025 at 3:55 PM
My teenager draws …