Senior Frontend Engineer

Salary: £52,000 - 92,000 per year

Requirements

• At least five (5) years as a software engineer, including three (3) at senior level, building front end for content-driven or marketing platforms.
• Real ownership of a content model in Sanity, including experience with schemas, references versus embedded objects, and section library design.
• Deep front-end expertise with expert HTML, CSS and TypeScript, plus strong component API design and shared library developer experience.
• Comfortable owning the server side as well as the front end, including SSR, serverless and edge runtimes, API routes, a SQL database, secrets and CI.
• Solid understanding of responsive design, cross-browser compatibility and web performance, and comfortable building to WCAG 2.2 AA.
• Strong understanding of marketing site measurement, including performance, SEO, analytics events and conversion.
• Strong craft, attention to detail, and the judgement to balance design intent against engineering constraints.
• Strong communication and collaboration skills, with a willingness to explain reasoning, review generously and help others grow.
• Nice-to-have experience with large SaaS marketing websites at scale.
• Nice-to-have experience with Astro or another islands/static-site framework.
• Nice-to-have experience with Cloudflare Workers, AWS Lambda, Tailwind CSS v4, token-based design systems, localisation and internationalisation at scale, analytics and tag management implementation, and AI-agent-friendly component libraries and content models.

Responsibilities

• Build, scale and evolve our section library, including Astro components, Sanity schemas and design tokens for consistent and accessible marketing pages.
• Own the content model and design schemas that resist misuse so pages are correct by construction.
• Take Figma component specs through to production, ensuring responsiveness, accessibility and fidelity to design intent.
• Extend the platform for AI-assisted development so coding agents can generate on-brand, on-spec sections reliably.
• Own SEO integrity as a first-class engineering concern, including canonicals, sitemaps, structured data, redirects and launch safety.
• Raise engineering standards across our website surface through code review, reusable patterns and targeted testing.
• Maintain and extend localisation across nine locales and our translation pipeline.
• Shape the technical direction of the website platform over the next 6 to 12 months and champion adoption with the people who publish on it.

Technologies

• AI
• API
• AWS
• Lambda
• CSS
• Datadog
• Embedded
• Figma
• Frontend
• Marketing
• SQL
• Serverless
• TypeScript
• Web
• Webflow
• Cloud
• AI Agents
• ARM
• Mobile

More

We are Synthesia, the worlds leading AI video platform for business, used by over 90% of the Fortune 100. Founded in 2017 and headquartered in London, we have teams across Europe and the US and continue to grow following our recent Series E funding round, which raised $200 million and brought our valuation to $4 billion. Our total funding now exceeds $530 million from premier investors including Accel, NVentures, Kleiner Perkins, GV and Evantic Capital, alongside the founders and operators of Stripe, Datadog, Miro and Webflow. For this Senior Frontend Engineer role on our Website team, we are looking for someone to help shape the platform behind synthesia.io, with a focus on composability, quality, performance and SEO. The role is based in London or remotely elsewhere in Europe subject to compliance and right to work checks, and it is full-time employment only, usually through OysterHR. Our hiring process includes a technical recruiter call, a discussion with our Head of Website, a collaborative practical exercise using a real Figma section spec, and a leadership conversation focused on collaboration and growth. We are passionate about building, not talking, planning or politicising, and we aim to hire smart, kind and unrelenting people who can do their best work without distractions.

last updated 35 week of 2026