David Allsopp
@dra27.uk
Cambridge-based singer and computer scientist. @dra27 in many places, including GitHub; OCaml maintainer; opam maintainer; Windows {apolog,evangel}ist
Being British, I’m of course able to read this both negatively and positively 🫢 news.ycombinator.com/item?id=4585...
Opam on Windows is a masterpiece of engineering | Hacker News
news.ycombinator.com
November 8, 2025 at 11:03 AM
Being British, I’m of course able to read this both negatively and positively 🫢 news.ycombinator.com/item?id=4585...
Unsure whether to be more shocked by the discovery that there will be 10 current/former lay clerks singing at this morning’s mass at Westminster Cathedral (first time for a decade?) or that they’ve completely renovated the 100 year old song school toilets!
October 5, 2025 at 9:44 AM
Unsure whether to be more shocked by the discovery that there will be 10 current/former lay clerks singing at this morning’s mass at Westminster Cathedral (first time for a decade?) or that they’ve completely renovated the 100 year old song school toilets!
Quite an extreme case of rewrite-it-in-Rust… www.nature.com/articles/d41...
The Moon is rusting — thanks to ‘wind’ blown all the way from Earth
Lunar minerals generate the rust mineral hematite when bombarded with high-energy oxygen particles, experiments show.
www.nature.com
September 23, 2025 at 7:06 AM
Quite an extreme case of rewrite-it-in-Rust… www.nature.com/articles/d41...
3 years since I finalised the demo of it for the OCaml Workshop in Ljubljana, Relocatable OCaml is finally submitted for review! 🥳🍾🎊
September 15, 2025 at 11:45 AM
3 years since I finalised the demo of it for the OCaml Workshop in Ljubljana, Relocatable OCaml is finally submitted for review! 🥳🍾🎊
Currently dotting ‘i’s and crossing ‘t’s and therefore wishing I’d used fewer ‘i’s and ‘t’s in my code (also, when I did I start handwriting code?? 🤔) #relocatable #ocaml
August 29, 2025 at 9:53 AM
Currently dotting ‘i’s and crossing ‘t’s and therefore wishing I’d used fewer ‘i’s and ‘t’s in my code (also, when I did I start handwriting code?? 🤔) #relocatable #ocaml
Reeling in shock and awe at just how simple and fast live-moving VM storage is in Hyper-V #scarred-by-esxi
August 27, 2025 at 6:59 AM
Reeling in shock and awe at just how simple and fast live-moving VM storage is in Hyper-V #scarred-by-esxi
Wonders how much water Apple could save each year by having Apple Mail offer to reduce the size of photos being emailed from an iPad in the same way as it does on an iPhone? 🤔🧐🤫
August 17, 2025 at 9:22 AM
Wonders how much water Apple could save each year by having Apple Mail offer to reduce the size of photos being emailed from an iPad in the same way as it does on an iPhone? 🤔🧐🤫
“I do not know whether there is anything peculiarly exciting in the air of this particular part of Hertfordshire, but the number of engagements that go on seems to me considerably above the proper average that statistics have laid down for our guidance.”
Good old Oscar 🤣
Good old Oscar 🤣
August 12, 2025 at 10:25 PM
“I do not know whether there is anything peculiarly exciting in the air of this particular part of Hertfordshire, but the number of engagements that go on seems to me considerably above the proper average that statistics have laid down for our guidance.”
Good old Oscar 🤣
Good old Oscar 🤣
Congratulations to Apple for anticlimax of the month with Apple “Intelligence”. In a metaphor for the age, seems all the time has been spent on the animations and hype and not a lot on it actually doing anything 🤷🏻♂️ #unabletosummarisethismessage
August 4, 2025 at 7:46 AM
Congratulations to Apple for anticlimax of the month with Apple “Intelligence”. In a metaphor for the age, seems all the time has been spent on the animations and hype and not a lot on it actually doing anything 🤷🏻♂️ #unabletosummarisethismessage
Reposted by David Allsopp
Yet another small OCaml/OxCaml diff has been squished! Polymorphic parameters has just gotten merged upstream:
github.com/ocaml/ocaml/...
There's more to go (include functor, for example: github.com/ocaml/RFCs/p...), but it's nice to see more progress in this space.
github.com/ocaml/ocaml/...
There's more to go (include functor, for example: github.com/ocaml/RFCs/p...), but it's nice to see more progress in this space.
Polymorphic Parameters by voodoos · Pull Request #13806 · ocaml/ocaml
This upstreaming PR adds the possibility to have function parameters with polymorphic types in the language.
This work was originally done by @lpw25 in Jane Street's fork of the compiler with e...
github.com
July 21, 2025 at 5:23 PM
Yet another small OCaml/OxCaml diff has been squished! Polymorphic parameters has just gotten merged upstream:
github.com/ocaml/ocaml/...
There's more to go (include functor, for example: github.com/ocaml/RFCs/p...), but it's nice to see more progress in this space.
github.com/ocaml/ocaml/...
There's more to go (include functor, for example: github.com/ocaml/RFCs/p...), but it's nice to see more progress in this space.
Testing opam packages for Relocatable OCaml which actually take advantage of it. Creating a new switch using the same version as one you've already built in another switch now takes 5 seconds, rather than 2 minutes (cloning the compiler itself takes just 100ms of that 5 seconds!)
July 20, 2025 at 3:11 PM
Testing opam packages for Relocatable OCaml which actually take advantage of it. Creating a new switch using the same version as one you've already built in another switch now takes 5 seconds, rather than 2 minutes (cloning the compiler itself takes just 100ms of that 5 seconds!)
Some very strong resonances for me (with thanks to @chshersh.com for drawing into my view over on X…)
Keynote: Rethinking our Adoption Strategy - Evan Czaplicki | Lambda Days 2025
YouTube video by Code Sync
youtube.com
July 2, 2025 at 3:38 PM
Some very strong resonances for me (with thanks to @chshersh.com for drawing into my view over on X…)
Childishly amused that the journey from Cambridge to Newcastle begins with a train to Liverpool #weregoingthewrongway
July 1, 2025 at 7:47 AM
Childishly amused that the journey from Cambridge to Newcastle begins with a train to Liverpool #weregoingthewrongway
Reposted by David Allsopp
I'm pleased to announce OxCaml!
OxCaml is Jane Street's branch of OCaml. We've given it a new name and a snazzy logo, and done a bunch of work to make it easy for people to try.
OxCaml is Jane Street's branch of OCaml. We've given it a new name and a snazzy logo, and done a bunch of work to make it easy for people to try.
June 13, 2025 at 2:14 PM
I'm pleased to announce OxCaml!
OxCaml is Jane Street's branch of OCaml. We've given it a new name and a snazzy logo, and done a bunch of work to make it easy for people to try.
OxCaml is Jane Street's branch of OCaml. We've given it a new name and a snazzy logo, and done a bunch of work to make it easy for people to try.
1994 (and earlier): select text in one “app”, copy, paste to another “app”
2025: select text in one app, copy, switch to other app and discover they’ve disabled paste on the input fields. Return to other app. Write information on piece of paper. Type into other app.
#progress #modern
2025: select text in one app, copy, switch to other app and discover they’ve disabled paste on the input fields. Return to other app. Write information on piece of paper. Type into other app.
#progress #modern
June 1, 2025 at 1:10 PM
Fell through a wormhole and sang the Solemn Passion + traditional Tallis Lamentations at Westminster Cathedral today. Realised the last time I did that was 17 years ago 🥺😳👴🏻
April 18, 2025 at 5:04 PM
Fell through a wormhole and sang the Solemn Passion + traditional Tallis Lamentations at Westminster Cathedral today. Realised the last time I did that was 17 years ago 🥺😳👴🏻
Reposted by David Allsopp
Uncle Sam abruptly turns off funding for CVE program. Yes, that CVE program
Uncle Sam abruptly turns off funding for CVE program. Yes, that CVE program
Because vulnerability management has nothing to do with national security, right?
US government funding for the world's CVE program – the centralized Common Vulnerabilities and Exposures database of product security flaws – ends Wednesday.…
dlvr.it
April 16, 2025 at 12:06 AM
Uncle Sam abruptly turns off funding for CVE program. Yes, that CVE program
Wondering if this is a judging stare about the delays getting Relocatable OCaml’s first pull request opened, or possibly something else… 🐈⬛ #catcaml
April 16, 2025 at 7:03 AM
Wondering if this is a judging stare about the delays getting Relocatable OCaml’s first pull request opened, or possibly something else… 🐈⬛ #catcaml
Possibly using them gratuitously, but I’m liking OCaml 5.4’s labelled tuples for logic setting up predicates. Nice to avoid stuff like
let p1, p2, (* … *) =
if (* something *) then
(true, false, false, true, true)
else if (* … *)
but without the weight of having to declare a record #ocaml
let p1, p2, (* … *) =
if (* something *) then
(true, false, false, true, true)
else if (* … *)
but without the weight of having to declare a record #ocaml
April 7, 2025 at 8:35 PM
Possibly using them gratuitously, but I’m liking OCaml 5.4’s labelled tuples for logic setting up predicates. Nice to avoid stuff like
let p1, p2, (* … *) =
if (* something *) then
(true, false, false, true, true)
else if (* … *)
but without the weight of having to declare a record #ocaml
let p1, p2, (* … *) =
if (* something *) then
(true, false, false, true, true)
else if (* … *)
but without the weight of having to declare a record #ocaml
Reposted by David Allsopp
uh oh AI safety meets OCaml and the seatbelts have come off real fast
March 29, 2025 at 1:44 PM
uh oh AI safety meets OCaml and the seatbelts have come off real fast
Initial idea - July 2019
Design proposal (before any code! 😇) - November 2019
Initial prototype - September 2021
Working prototype - September 2022
Candidate implementation - April 2025 #RAD 🫣
Design proposal (before any code! 😇) - November 2019
Initial prototype - September 2021
Working prototype - September 2022
Candidate implementation - April 2025 #RAD 🫣
Relocatable OCaml by dra27 · Pull Request #53 · ocaml/RFCs
Rendered version. The first proof-of-concept of this work was presented at OCaml Workshop 2022.
The OCaml compiler distribution requires the Standard Library to be stored in a fixed location, speci...
github.com
March 27, 2025 at 8:41 AM
Initial idea - July 2019
Design proposal (before any code! 😇) - November 2019
Initial prototype - September 2021
Working prototype - September 2022
Candidate implementation - April 2025 #RAD 🫣
Design proposal (before any code! 😇) - November 2019
Initial prototype - September 2021
Working prototype - September 2022
Candidate implementation - April 2025 #RAD 🫣