Front-end web developer, Hackworth Ltd, London (POSITION FILLED)

Update: this position has now been filled and is no longer available. Thanks for your interest!

Hi all. Hackworth Ltd are hiring a full time front-end web developer in London. This is an on-site role. However, due to the COVID-19 pandemic, we’re all working from home somewhere in the UK until it’s safe to return to a shared office space.

Salary range: £50,000—£60,000 per year

In this role, you’ll help us prototype and build the user interface for our first product: a novel, interactive learning environment for programming, rooted in functional programming principles, with a particular focus on structure editing and the visualization of program execution. You’ll join our existing team of 3 Haskell developers and (soon) a UX designer.

We’re currently in the prototyping phase, so over the next 6 months, you’ll have the opportunity to invent novel user interfaces and interactions for helping kids learn to program. In the spring of 2021, we’ll begin production work, with the goal of beginning beta testing with schools and learning organizations by the end of 2021.

This role does not include any on-call, devops, or customer support requirements. You’ll be focused exclusively on creating a great programming environment for kids and teachers.

For more information, please see the full job posting on our web site.


Our software stack to date is Haskell and Nix. We use macOS and NixOS on the desktop, and NixOS and AWS services everywhere else.

We’ve yet to decide on a front-end web-native language and framework, but given the Haskell backgrounds of the current developer team, we’re hoping to find someone who’s proficient in PureScript, hence the job posting here.

About us

Hackworth Ltd is a well-financed, bootstrapped, private limited company based in London. Our purpose is to make programming relevant to the interests of children of all backgrounds.

We’re committed to building a sustainable, ethical, socially responsible business. We serve children and schools; therefore, we’ll never fund our business by selling ad placements or exploiting compulsion loops via loot boxes or micro-transactions. See our about page for more.


To apply for this role, you should meet the following requirements:

  • At least 2 years’ experience developing production-quality web-based user interfaces.
  • You can be on-site at our London office at least 4 days per week, once it’s safe to return to a shared office space.
  • You’re eligible to work in the United Kingdom. (Sorry, we cannot sponsor visas!)

If you’re familiar with any of the following topics, that’s a definite plus, and you should mention it in your application, but please note that these are not required for the role:

  • Assistive technologies (screen readers, ARIA, etc.)
  • D3.js, WebGL, or other HTML5 canvas-based graphics APIs
  • Structure editing a la Hazel
  • Block-based programming a la Scratch or Blockly


We offer 25 paid holidays per year (in addition to public holidays), a generous parental leave policy, pension contribution-matching, and the option of a 4-day work week, plus other perks. For more about working at Hackworth, please visit our jobs page.

To apply

To apply for this role, please submit a CV to Even if you’re unsure about your fit, or if you have any additional questions about the role, or about working at Hackworth in general, please get in touch! And please feel free to ask questions here in the comments, as well.

Hackworth are committed to diversity. We are an equal opportunities employer and do not discriminate on the grounds of gender, sexual orientation, marital or civil partner status, pregnancy or maternity, gender reassignment, race, colour, nationality, ethnic or national origin, religion or belief, disability or age.


Edit: we’ve increased the salary range to £50,000-£60,000 per year for this role.


Hi @dhess I am from India and I am interested in this opportunity, I am not eligible to work in UK, let me know your thoughts

Hi @Abinaya, thanks for your interest in the role! Unfortunately, as stated in the description, this is a UK-only role and we can’t sponsor visas at this time, I’m afraid. Sorry!

I’m just curious, as a proponent of code world, how your product would compare? Feel free to direct me elsewhere, and good luck!

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Thanks for the good wishes!

CodeWorld is very inspiring, and I admire and respect all the work Chris Smith has done to create it. We want to try a different approach, but our long-term goals are the same as Chris’s, and I don’t see Chris or CodeWorld as “the competition.” The more kids who learn to program, the better, and I don’t particularly care what system they use, so long as it’s effective.

Anyway, the crucial difference is that CodeWorld actually exists! :blush: We’re still working on our project and probably won’t have anything to demonstrate until late next year.

All joking aside, one important difference between CodeWorld and what we’re attempting to do is that we’re not proposing to teach Haskell to beginners. Our language is similar to Haskell, but designed from first principles to be an effective language for learning functional programming.

Aside from any pedagogical advantages our language may theoretically have over Haskell – and let me be clear that I’m not claiming that yet, as it will require lots of testing and user feedback to assess whether we’ve succeeded – another, more concrete advantage of writing our own language is that we can design it together with the environment that kids will use to write programs. With the exceptions of Scratch and the Smalltalk family, nearly ever other language that kids use to learn programming was designed to parse a text file and then either execute it directly, or spit out an object file, splatting out error messages to the console along the way.

Scratch & Smalltalk, on the other hand, were designed with the principle that the language and the programming environment should be designed hand-in-hand. We’re taking the Scratch & Smalltalk approach, but applying it to functional programming.


I’m very glad to see more products like CodeWorld being worked on!

@dhess Just to put this idea out there - Have you considered Concur’s model for animations and user-interface programming?

With other approaches, the leap from static diagrams to user interfaces which take user input is huge. Concur’s model on the other hand is very gentle and lends itself very well to teaching FP to newbies.
Here’s an example of what I mean -

It also helps that it also scales to real world programs and lets you use your full set of FP idioms. More information at


@ajnsit Sorry, I’m not sure whether you’re suggesting we use Concur to build our application, or use Concur’s model for teaching UI programming to beginners.

@dhess I was suggesting the latter.

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