Past Meetup

Comonads all the way down (by Tom Harding)

This Meetup is past

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The Cooperage, 5 Copper Row, London, SE1 2LH · London

How to find us

Use Copper Row pedonal path, enter the little square with the mermaid fountain and search the stairs with the ZPG sign.

Location image of event venue


Tom Harding ( , presents a talk on " Comonads all the way down" inspired by the paper "Declarative UIs are the Future — And the Future is Comonadic!" by Phil Freeman.

Download the paper at:


Anyone who has been involved with front-end development over the last
few years will have seen drastic changes in the way we approach UIs.
As we move from jQuery to React, the trend has been clear: we want our
UIs to be declarative functions from our state to our HTML. So...
what's next?

Phil's conference paper introduces comonads as the abstraction to
represent the properties we want in our UIs, and explores the powerful
ways in which they compose. In this talk, we'll follow along with the
beloved language of JavaScript, and see how we can use these examples
in our work today.

The Speaker

Tom is a lead engineer at Habito, the digital mortgage broker built
entirely in Haskell and PureScript. He works on a project derived from
this paper, purescript-panda: a UI library built around the idea of
incremental rendering.


We meet at ZPG ( offices near Tower Bridge ( with the following schedule:

• 6.30pm: networking, pizza and drinks.
• 7:00pm: presentation starts

Meetup are captured on video and uploaded at