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StackAI

Senior Frontend Engineer

full-time•Madrid

Summary

Location

Madrid

Type

full-time

Experience

5-10 years

Company links

Website

About this role

About Stack AI

Stack AI is democratizing access to Large Language Models through a user-friendly no-code platform integrating the best AI models (OpenAI, Anthropic, Google), data sources (OneDrive, Google Drive, Notion), and SaaS tools. We're backed by Y Combinator and Gradient Ventures, with thousands of users and hundreds of paying customers including public companies and unicorns.

The Role

We're looking for a senior frontend engineer who is incredible at execution. This is not about building flashy new features from scratch—it's about optimizing, refining, and incrementally improving what we've already built. You'll work closely with our Product Design pod to turn detailed visual specs into clean, production-ready code.

Main Mission: Remove the bottleneck in our Product Design pod by taking ownership of incremental UX/UI improvements to existing features and code.

What You'll Do

  • Optimize and refine existing frontend code and features

  • Implement incremental UX/UI improvements from detailed design specs (no design skills required)

  • Work autonomously with minimal code review needed—your code should be clean enough that our other Front Enders can trust it blindfolded

  • Collaborate with Product Designers, Design Engineers, and Front End Engineers on execution

  • Focus on high-impact improvements that elevate our product quality and user experience

  • Clean up and improve legacy code

What We're Looking For

Must-haves:

  • Exceptional code quality: Clean, maintainable, trustworthy code that requires minimal review

  • Strong execution: You ship fast and ship well

  • Senior-level experience: 5+ years with React, TypeScript, Next.js, and modern frontend stack

  • Accountability: You own your decisions and respond when needed

  • Autonomy: You can own features end-to-end without hand-holding

  • Pragmatism: You are willing to engage with detail-oriented and iterative work that is essential to the product's success

  • Technical excellence: Someone who can teach us, not someone we have to teach

Nice-to-haves:

  • Experience with Tailwind CSS

  • Understanding of UI fundamentals (but design skills are NOT required)

  • Experience cleaning up and optimizing existing codebases

  • Comfort working across the stack when needed

Our Tech Stack

React, Next.js, TypeScript, Tailwind CSS, TanstackQuery

What We Value

  • High bar: We only hire people who wow us technically—someone better than us

  • Trust: We've learned that even "boring tasks" require exceptional engineers, because poor execution takes more time to review than to do right the first time

  • Execution over excitement: You're motivated by doing excellent work, not just working on the newest, shiniest features

Why This Role Matters

The Product Design pod has ambitious plans in the roadmap, and we need a frontend engineer who can execute flawlessly to keep pace. You'll be critical to ensuring our product quality and velocity.

This role description captures the team's emphasis on exceptional technical quality, execution, and pragmatism over design skills or working on only the most exciting features.

What you'll do

  • The Senior Frontend Engineer will optimize and refine existing frontend code and features, focusing on incremental UX/UI improvements. They will collaborate with the Product Design pod to enhance product quality and user experience.

About StackAI

About StackAIStack AI is a no-code drag-and-drop tool to quickly design, test, and deploy AI workflows that leverage Large Language Models (LLMs), such as ChatGPT, to automate any business process. Our core value is to make it extremely easy to build arbitrarily complex AI pipelines using a visual interface that allows you to connect different data sources with different AI models.Our customers use Stack AI to build applications such as:Chatbots and Assistants : AI agents that interact with users, answer questions, and complete tasks, using your internal data and APIs.Document Processing : apps to answer questions, summarize, and extract insights from any document, no matter how long.Answer Questions on Databases : connect GPT-like models to databases (such as Notion, Airtable, or Postgres) and ask questions about them.Content Creation : generate tags, summaries, and transfer styles or formats between documents and data sources.

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Frequently Asked Questions

What does a Senior Frontend Engineer do at StackAI?

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As a Senior Frontend Engineer at StackAI, you will: the Senior Frontend Engineer will optimize and refine existing frontend code and features, focusing on incremental UX/UI improvements. They will collaborate with the Product Design pod to enhance product quality and user experience..

Is the Senior Frontend Engineer position at StackAI remote?

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The Senior Frontend Engineer position at StackAI is based in Madrid, Community of Madrid, Spain. Contact the company through Clera for specific work arrangement details.

How do I apply for the Senior Frontend Engineer position at StackAI?

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You can apply for the Senior Frontend Engineer position at StackAI directly through Clera. Click the "Apply Now" button above to start your application. Clera's AI-powered platform will help match your profile with this opportunity and guide you through the application process.
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