Senior Full Stack Web Developer

Praktika.ai; Greater London; On-site; GBP 90,000 - 120,000; Full time

Job summary

Praktika.ai seeks a Senior Full-Stack Engineer to own every web-facing surface — onboarding flows, landing pages, customer portals, web app and internal tools. This full-cycle role lets you shape product direction, run experiments, ship features end-to-end, and measure impact on conversion, retention, and learner experience.

You’ll collaborate with Product, Marketing, and Growth, influencing product decisions and driving architecture.

Qualifications

• Senior-level full-stack engineer responsible for web surfaces across marketing site, onboarding, portals, web app and internal tools.
• Proficiency with modern full-stack tooling (TypeScript, React, Next.js) and strong UI/UX sensibilities.
• Data-driven with experience in analytics, experimentation, and conversion-focused product decisions.

Responsibilities

• Own the entire web stack: marketing site, onboarding funnels, customer portals, web app, and internal tools.
• Lead architecture, development, experimentation, and operations across all web applications.
• Drive product decisions: design and run A/B tests, analyze results, and iterate based on data.
• Build adaptive, animated, mobile-first experiences that convert and delight users.

Skills

Full-stack

TypeScript

React

Next.js

RESTful APIs

A/B testing

Analytics

UI/UX

Mobile-first

Tools

Next.js

CSS-in-JS

Tailwind

LaunchDarkly

Flagsmith

Amplitude

PostHog

Firebase

Auth0

Stripe

PayPal

RevenueCat

Job description

• We’re hiring a Senior Full-Stack Engineer to own and evolve every web-facing surface at Praktika; onboarding flows, landing pages, customer portals, our web app, and internal tools. This is a full-cycle product engineering role: you’ll shape product direction, design and run experiments, ship features end-to-end, and measure their impact on conversion, retention, and learner experience
• You’ll partner closely with Product, Marketing, and Growth, and your work will directly influence how tens of millions of learners discover and engage with Praktika
• Own the entire web stack: marketing site, onboarding funnels, customer portals, web app, and internal tools
• Lead architecture, development, experimentation, and operations across all web applications
• Drive product decisions: contribute to the vision, design and run A/B tests, analyze results, and iterate quickly
• Build adaptive, animated, mobile-first experiences that convert and delight users
• Integrate with backend services (via Swagger docs), authentication providers (Google/Apple SSO), and payment gateways (Stripe, PayPal, RevenueCat)
• Set up and optimize analytics, tracking, and conversion funnels in collaboration with Growth and Marketing
• Ship production-ready code end-to-end; from idea through deployment to monitoring

We’re looking for outstanding engineers who thrive in a challenging environment, bring a growth mindset, and operate with a high degree of agency, devotion, and autonomyProduct-first mindset: you think in user problems and business outcomes, not just codeProficiency across modern full-stack tooling: Next.js (or equivalent), CSS-in-JS or TailwindStrong UI/UX sensibility; you care about animation, micro-interactions, and conversion detailsData-driven approach with proven experience in A/B testing, funnel optimization, and analyticsHands-on experience integrating auth providers (Firebase, Auth0), payment systems (Stripe, RevenueCat, PayPal), feature-flag platforms (LaunchDarkly, Flagsmith), and analytics tools (Amplitude, PostHog)Comfortable working with RESTful APIs and collaborating closely with backend teamsExtensive experience with TypeScript, React (hooks, context, state management), and Node.jsAbility to thrive in an async, distributed, written-first culturePrior experience at an early-stage or high-growth consumer product companyA portfolio of high-quality web projects and successful conversion experiments