Senior Front-End Engineer

Position: Senior Front-End Engineer

Company: Abra

Location: Remote (Brazil – EST hours)

Type: Full-time

About Abra

Abra builds promotional tools that help Shopify merchants run better sales and increase conversions. We’re a team of Shopify alumni, designers, and developers obsessed with UX, product craftsmanship, and merchant success. Our app powers complex promotions on high-volume Shopify stores, across their storefronts, mobile apps, and checkout and we're scaling fast.

We’re looking for a senior front-end engineer to own everything that runs client-side at Abra: the components shoppers see on merchant storefronts and mobile apps, our embedded app admin, and the building blocks our partners use to create their own experiences on top of Abra. You’ll work closely with the founders, our lead engineer, and our designer to make our front end fast, clean, and easy to build on.

What You’ll Do

• Build new storefront components and improve their UX (promotional messaging, wallet and loyalty experiences, and more)
• Build and maintain the SDK, web components, and APIs that let partners and third-party developers build their own experiences on top of Abra
• Own client-side quality across our storefront code, mobile app blocks, and Shopify UI extensions. Making sure everything is fast, performant, and reliable on every merchant's store
• Improve the performance and readability of our storefront JavaScript​: less resource usage, faster code, better Core Web Vitals
• Keep our admin front end lean. Clean up and consolidate repeated patterns, and make it as efficient and regression-proof as possible.
• Establish and improve automated testing, monitoring, and regression prevention across our client-side systems
• Own front-end technical decisions, from architecture and technical planning to implementation, testing, and rollout
• Rapidly prototype and experiment with new front-end experiences, helping the team validate ideas before investing in full implementation

What You’ll Need

• Strong JavaScript and TypeScript fundamentals: data structures, browser APIs, and JavaScript performance
• Deep experience with React
• Experience shipping code that runs in environments you don’t control, like embedded widgets, SDKs, or scripts on third-party websites
• Experience designing and shipping SDKs or libraries that other developers build on (API design, versioning, documentation)
• Hands-on experience building and integrating web components (Custom Elements, Shadow DOM, events). The framework doesn't matter: Lit, Preact, or plain JavaScript are all great
• A strong UX sense: you can turn rough ideas into functional prototypes, explore different approaches, and refine the experience through iteration without needing pixel-perfect mockups
• Ownership from scoping through rollout: you break down ambiguous problems, address unknowns early, and test your work thoroughly
• Proficiency with AI-assisted development tools to accelerate prototyping, implementation, debugging, and everyday engineering workflows
• Strong async communication and documentation skills in a remote environment
• Strong product instincts: you can think beyond implementation, challenge assumptions, suggest improvements, and help shape solutions that deliver a better user experience

Nice to Have

• Experience with Shopify themes, app extensions, or Shopify app development (Liquid, Polaris, UI extensions)
• Experience with mobile commerce platforms like Tapcart
• A track record of improving Core Web Vitals or Lighthouse scores on high-traffic sites

Why Join Us

• Fast-growing startup with product-market fit
• Flexible remote work
• Real ownership: shape the architecture of our front end and the platform partners build on
• Small, senior team with high product and engineering standards
• Clear paths to grow into staff-level engineering or technical leadership roles