Allan Clark

I’m a programmer in Edinburgh. I write here mostly about programming languages and their features; types, laziness, syntax design, and how little evidence we actually have for the things we believe about them. I think many of my posts do not take a strong position or if they do I end up arguing against it.

I am available for work, contract, consultancy, or potentially for the right place a full-time role.

I co-founded and built Pakk Software, an e-commerce platform for small and medium-sized businesses. Most of my recent work has been in Elm, on both the front end and the back end but I’ve worked in various other languages including Haskell, C, Java, Python and even Go. I also spent several years as a researcher in formal (largely performance) modelling.

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I run a Formula 1/E prediction game Pole Prediction.

Start here

Ladybird overtakes Servo: Why?
A C++ browser engine is outpacing a Rust one, this goes against my priors that stronger guarantees are generally good for programming so I listed other reasons why this might happen, but I wasn’t convinced by any of them.
Small functions and Elm
Function length is the wrong proxy for the thing we actually want.
Weak typing - What is it good for
Probably not absolutely nothing, but I think weakly typed languages are mostly useless, so I try to steelman the case for one
Dynamically/Statically typed language and meta-programming
Why you can write a generic admin panel in Python and not in Elm — explained down at the level of what’s actually in memory.
Laziness would be good for Time.Extra.posixToParts
A good example of what I think laziness is good for, allowing natural structuring code
Stacks and Laziness
The follow-up where I explain why laziness is not a silver bullet that always works.
Structural Custom Types
Extensible union types are often proposed. I think the important difference is between structural and nominal types, and that this should be uniform across records and custom types.
Scoring Orders
Our F1 prediction scoring let a randomly-generated guess beat a nearly-correct one. Here’s the system I built to fix it.
Legal standing analogy
Before proposing a feature, show standing. An under-rated analogy from Dillon Kearns.
Review: Mo Gawdat: Diary of a CEO
I go through a podcast episode I was asked to listen to, and find that there isn’t much substance to the arguments.

Recent

2026-08-10 Link: Danluu.pl: Programming language and token efficiency
2026-08-07 Video Link: Reliability lessons from SQLite at Software Should Work
2026-08-06 Link: Twenty years of Pandoc
2026-08-03 Internationalisation and automatic translation
2026-07-31 Video Link: Dependency Cultures: Software Should Work
2026-07-28 Link: Functional Programming from First Principles
2026-07-10 Fantasy Top Goalscorer
2026-07-06 Scoring Orders

All 168 posts →