# The 3rd Programming for the Planet 2026 videos are available

*2026-08-28 — note*


The recordings from the 3rd ACM [Programming for the Planet](https://pldi26.sigplan.org/home/propl-2026) (PROPL)
workshop have gone live on PLDI's [YouTube playlist](https://www.youtube.com/playlist?list=PLXeET4GjfkHs).
As usual I've mirrored them onto our self-hosted [Watch EEG instance](https://watch.eeg.cl.cam.ac.uk).
I [attended remotely](https://anil.recoil.org/notes/2026w25) this year as I couldn't make it across the ocean, and enjoyed rewatching the
talks.

This was the third outing of PROPL after [London in 2024](https://anil.recoil.org/projects/plancomp) and
[Singapore last year](https://anil.recoil.org/notes/icfp25-propl). We decided to split the workshop into two
halves this year: a morning of position talks followed by an afternoon of working groups aimed
at action items for the community.

The morning talks are what's recorded below, and [Cyrus Omar](https://web.eecs.umich.edu/~comar/), [Dominic Orchard](https://dorchard.github.io), [KC Sivaramakrishnan](https://kcsrk.info) and I will be working on
summarising the
[living document](https://docs.google.com/document/d/1ZPUsfBinY1bKiXg-nuKDoEcIEqpL9d2BdOI5FuBfusk/edit),
(which covers a wide gamut of user experience, interoperability, scaling, AI and sociotechnical
challenges) over the coming months. I'm also delighted that [Cyrus Omar](https://web.eecs.umich.edu/~comar/), who chaired this year's workshop, will be
spending his sabbatical year in Cambridge from October 2026 as an Associate Scholar at
[Pembroke College](https://www.pem.cam.ac.uk/) as well as a visiting academic at the
[Computer Lab](https://www.cst.cam.ac.uk/), hosted by me\!

<a href="https://pldi26.sigplan.org/home/propl-2026"> <figure class="image-center"><img src="/images/propl-comar-1.webp" alt="" title="" loading="lazy" srcset="/images/propl-comar-1.768.webp 768w, /images/propl-comar-1.640.webp 640w, /images/propl-comar-1.480.webp 480w, /images/propl-comar-1.320.webp 320w, /images/propl-comar-1.1920.webp 1920w, /images/propl-comar-1.1600.webp 1600w, /images/propl-comar-1.1440.webp 1440w, /images/propl-comar-1.1280.webp 1280w, /images/propl-comar-1.1024.webp 1024w"><figcaption></figcaption></figure> </a>

For those curious, the [entire talk series](https://watch.eeg.cl.cam.ac.uk/c/propl24/videos) from all three PROPLs
is an interesting watch. I'm very much looking forward to distilling them into something actionable
among the PL community (especially given enthusiastic [followups](https://anil.recoil.org/notes/2026w15) from bright sparks like
Manuel Rigger and [Aadi Seth](https://www.cse.iitd.ac.in/~aseth/) who I _really_ want to [do more projects with](https://anil.recoil.org/notes/first-tessera-hackathon)!).
Ideas for the next PROPL are very welcome from anyone else who fancies joining in and/or
contributing to organisation ideas.

## Onto the PROPL talks

[Cyrus Omar](https://web.eecs.umich.edu/~comar/) opens by arguing that a [future digital commons for science](https://anil.recoil.org/notes/nas-rs-biodiversity-papers) must not merely
*store* data under FAIR principles, but also [compute](https://anil.recoil.org/papers/2025-fairground) over it, with
provenance and reproducibility as first-class concerns rather than things we bolt on
afterwards.

<div class="video-center"><iframe title="Cyrus Omar sets the scene for the third PROPL" width="100%" height="315px" src="https://watch.eeg.cl.cam.ac.uk/videos/embed/cf84d09f-1ce0-4212-b3a3-2ccee3fa5622" frameborder="0" allowfullscreen sandbox="allow-same-origin allow-scripts allow-popups allow-forms"></iframe></div>

## Marrying engineering rigor and scientific rigor for the planet

Deepak Cherian of [Earthmover](https://www.earthmover.io/) discusses what Earth science could
usefully steal from the database community, by way of
[Icechunk](https://www.earthmover.io/blog/icechunk/). This is a cloud-native chunked array store
with version control, isolated transactions and snapshots. As Deepak notes, "the pile-of-files
model severely lacks rigor", which anyone reading mine or [Mark Elvers](https://www.tunbury.org/) [weeknotes](https://anil.recoil.org/notes/2026w31) about managing [TESSERA](https://anil.recoil.org/projects/tessera) embeddings between machines will no doubt agree with.

<div class="video-center"><iframe title="Deepak Cherian on rigor at the storage, compute and science layers" width="100%" height="315px" src="https://watch.eeg.cl.cam.ac.uk/videos/embed/1b31ad4c-51ba-4be5-8af4-6c0732e34fdd" frameborder="0" allowfullscreen sandbox="allow-same-origin allow-scripts allow-popups allow-forms"></iframe></div>

## A compiler-first planetary compute engine

[Billy Moses](https://wsmoses.com/academic) and a big cast had the most ambitious project I've seen in a while. They're working on making Earth system models end-to-end differentiable
and hardware-portable at the *compiler* level, rather than by asking scientists to rewrite
a million lines of Fortran.

[Enzyme](https://enzyme.mit.edu/) is a project that does the automatic differentiation down at the LLVM IR,
and a Reactant frontend lowers to [StableHLO](https://openxla.org/stablehlo). This means that the same ocean and atmosphere models run on
AMD, NVIDIA and TPU hardware. Differentiable models make calibration, sensitivity analysis
and [uncertainty quantification](https://anil.recoil.org/papers/2024-uncertainty-cs) tractable.

<div class="video-center"><iframe title="Billy Moses on differentiability and portability as compiler infrastructure" width="100%" height="315px" src="https://watch.eeg.cl.cam.ac.uk/videos/embed/87536e7a-9a4c-422f-9f20-446193621cce" frameborder="0" allowfullscreen sandbox="allow-same-origin allow-scripts allow-popups allow-forms"></iframe></div>

As a followup, Yossi Frenkel then [noticed](https://eeg.zulipchat.com/#narrow/channel/528403-Coding/topic/Autodiff.20in.20Rust.20standard.20library/near/619160831) that Rust is [proposing](https://github.com/rust-lang/compiler-team/issues/611) integrating an auto-differentiation module into the standard library as `std::autodiff`. So it looks like Enzyme is being adopted more widely.

## Mind the (semantic) gap

[Dominic Orchard](https://dorchard.github.io) then spoke about the semantic chasm between the equations in a paper and the code that
attempts to implement them. He makes the case for languages whose types carry "domain meaning":
units, physical structure, and other invariants scientific computing code needs to enforce statically and avoid
misuse. This tracks his [Camfort](https://camfort.github.io/) units-of-measure line of thinking, but far more
baked into a fresh type system rather than retrofitted.

<div class="video-center"><iframe title="Dominic Orchard on minding the gap between equations and code" width="100%" height="315px" src="https://watch.eeg.cl.cam.ac.uk/videos/embed/606a7f50-a534-4361-a864-75198b60a7a4" frameborder="0" allowfullscreen sandbox="allow-same-origin allow-scripts allow-popups allow-forms"></iframe></div>

## The Basic Model Interface

Mark Piper then talked about the [BMI](https://bmi.csdms.io/), a (deliberately) minimal language-agnostic
spec of about thirty functions for coupling numerical models. It has been crowdsourced over years
through the [CSDMS](https://csdms.colorado.edu/) community. I found this talk to be a useful counterweight to the
grander architectural proposals, as it covered essential nitty gritty data management tasks (which is about 90% of
the work involved in most of this research!). It's also a useful reminder that simplicity in interfaces makes them
much more likely to survive and be implemented in a community that's distributed around different toolchains and languages.

<div class="video-center"><iframe title="Mark Piper on the Basic Model Interface" width="100%" height="315px" src="https://watch.eeg.cl.cam.ac.uk/videos/embed/872a2fe6-a73d-43da-a1ff-a11db3b9fb69" frameborder="0" allowfullscreen sandbox="allow-same-origin allow-scripts allow-popups allow-forms"></iframe></div>

Stay tuned for further updates, and thank to Yossi Frenkel for alerting to me to the PLDI videos being published\!
Synopsis: Videos from the third Programming for the Planet (PROPL) workshop at PLDI 2026, and Cyrus Omar is visiting Cambridge on sabbatical for a year to drive followups!
Words: 732
DOI: 10.59350/tdd9c-wmx92

## Related

- [Marrying engineering rigor and scientific rigor for the planet (PROPL 2026)](https://anil.recoil.org/videos/1b31ad4c-51ba-4be5-8af4-6c0732e34fdd) (video, 2026-08-26)
- [Mind the Gap: General-Purpose Programming Languages Impede Scientific Model Development and Communication (PROPL 2026)](https://anil.recoil.org/videos/606a7f50-a534-4361-a864-75198b60a7a4) (video, 2026-08-26)
- [The Basic Model Interface (BMI) (PROPL 2026)](https://anil.recoil.org/videos/872a2fe6-a73d-43da-a1ff-a11db3b9fb69) (video, 2026-08-26)
- [A Compiler-First Planetary Compute Engine: Automatic differentiable and performance portable Earth System Modeling (PROPL 2026)](https://anil.recoil.org/videos/87536e7a-9a4c-422f-9f20-446193621cce) (video, 2026-08-26)
- [Introduction (PROPL 2026)](https://anil.recoil.org/videos/cf84d09f-1ce0-4212-b3a3-2ccee3fa5622) (video, 2026-08-26)
- [.plan-26-31: Sorting out Tessera and Evidence TAP infrastructure](https://anil.recoil.org/notes/2026w31) (note, 2026-08-02)
- [.plan-26-25: Planetary scale plans, Windows file-descriptor scale problems](https://anil.recoil.org/notes/2026w25) (note, 2026-06-21)
- [.plan-26-15: Banyan trees, (anti)botnets and Bose-Einstein bases](https://anil.recoil.org/notes/2026w15) (note, 2026-04-12)
- [Connecting the dots for biodiversity action from the NAS/Royal Society Forum](https://anil.recoil.org/notes/nas-rs-biodiversity-papers) (note, 2026-03-07)
- [1st TESSERA/CoRE hackathon at the Indian AI Summit](https://anil.recoil.org/notes/first-tessera-hackathon) (note, 2026-02-19)
- [Programming for the Planet at ICFP/SPLASH 2025](https://anil.recoil.org/notes/icfp25-propl) (note, 2025-10-05)
- [A FAIR Case for a Live Computational Commons](https://anil.recoil.org/papers/2025-fairground) (paper, 2025-10-01)
- [TESSERA, a pixelwise geospatial foundation model](https://anil.recoil.org/projects/tessera) (project, 2025-01-01)
- [Uncertainty at scale: how CS hinders climate research](https://anil.recoil.org/papers/2024-uncertainty-cs) (paper, 2024-02-01)
- [Planetary Computing](https://anil.recoil.org/projects/plancomp) (project, 2022-01-01)

---
Canonical: https://anil.recoil.org/notes/pldi26-propl
Type: note
Tags: programming, climate, conference, academia, functional