Is this event free to attend?

Yes. Leeds JS events are free. No ticket price is listed on the Meetup page.

Where exactly is the venue?

CGI Leeds, 1 Whitehall Quay, Leeds, LS1 4HR. It is a short walk from Leeds railway station, on the south bank of the Aire.

Do I need to register in advance?

Yes. RSVP via the Leeds JS Meetup page at meetup.com/leeds-js. Places are limited so register early.

What time does the event start and finish?

Doors and welcome from 6:00 pm BST. The programme runs until approximately 8:00 pm, with networking and drinks afterwards.

Is this suitable if I am not a JavaScript specialist?

The organisers describe it as open to frontend engineers, full-stack developers and anyone curious about web performance. WebAssembly knowledge is not required.

talk · Monthly · dates vary

Web Performance Special with Harry Roberts & Leaning Technologies

Name: Web Performance Special with Harry Roberts & Leaning Technologies
Start: 2026-05-26T17:00:00.000Z
Location: CGI Leeds

Web performance deep-dive with Harry Roberts and Leaning Technologies

When

Tuesday 26 May

Time

17:00

Venue

CGI Leeds

City Centre

Price

Free

Reserve a spot →

Leeds JS is dedicating its May 2026 meetup entirely to web performance. Harry Roberts — consultant at csswizardry.com, international speaker, and someone who has worked with Google, the BBC and the Financial Times on real-world performance problems — will headline the evening with a talk titled Thinking Like a Performance Engineer. Expect practical material on diagnosing bottlenecks and making performance a genuine part of engineering culture, not an afterthought.

Also on the bill is Ana Gabriela Reyna Flores, a Developer Relations engineer at Leaning Technologies, covering high-performance web apps and WebAssembly. The format is two talks followed by a Q&A and community discussion, then networking with drinks. It runs 6–8 pm at CGI Leeds on 1 Whitehall Quay. The audience skews frontend and full-stack, but the organisers describe it as open to anyone who cares about how fast their code actually runs in a browser.

Leeds JS has been running free monthly meetups in Leeds city centre for years, bringing in local and national speakers across the JavaScript and web development spectrum. Events typically draw a mix of junior developers, senior engineers and the occasional hiring manager. This one is a step up in profile — Harry Roberts is one of the more recognisable names on the international conference circuit when it comes to web performance specifically, and getting him to a free Tuesday-evening meetup in Leeds is worth noting.

Why attend

Harry Roberts has a track record of fixing performance problems at organisations with serious scale — Google, the BBC, the Financial Times. His talk is billed as practical and diagnostic rather than theoretical, so you should leave with techniques you can apply to your own codebase.

Ana Gabriela Reyna Flores brings a WebAssembly angle that does not often appear at Leeds meetups. If you work on anything performance-sensitive in the browser, that perspective is worth an hour of your evening. Networking and drinks follow the talks, and entry is free.

Agenda

Welcome & intros
Talk: Ana Gabriela Reyna Flores — Leaning Technologies DevRel (WebAssembly and high-performance web apps)
Talk: Harry Roberts — Thinking Like a Performance Engineer
Q&A + community discussion
Networking & drinks

Speakers

Harry Roberts — web performance consultant (csswizardry.com); has worked with Google, the BBC and the Financial Times; international conference speaker
Ana Gabriela Reyna Flores — Developer Relations at Leaning Technologies; focus on WebAssembly and high-performance browser applications

Organiser

Leeds JS

Leeds JS runs free monthly meetups for the JavaScript and web development community in Leeds. Events are hosted at venues across the city centre and cover everything from framework deep-dives to tooling and performance. The group is co-organised by Colin W., Rich M. and others.

Venue

CGI Leeds, City Centre

CGI Leeds occupies 1 Whitehall Quay on the south bank of the River Aire, a short walk from Leeds station. The building hosts several tech-sector tenants and is a regular venue for Leeds JS and other community meetups.

FAQs

Is this event free to attend?: Yes. Leeds JS events are free. No ticket price is listed on the Meetup page.
Where exactly is the venue?: CGI Leeds, 1 Whitehall Quay, Leeds, LS1 4HR. It is a short walk from Leeds railway station, on the south bank of the Aire.
Do I need to register in advance?: Yes. RSVP via the Leeds JS Meetup page at meetup.com/leeds-js. Places are limited so register early.
What time does the event start and finish?: Doors and welcome from 6:00 pm BST. The programme runs until approximately 8:00 pm, with networking and drinks afterwards.
Is this suitable if I am not a JavaScript specialist?: The organisers describe it as open to frontend engineers, full-stack developers and anyone curious about web performance. WebAssembly knowledge is not required.