Senior Full Stack Engineer

Jobtailor; Seattle (WA); On-site; USD 140,000 - 210,000; Full time

Job summary

Jobtailor in Seattle seeks a senior full-stack engineer to own features end-to-end across API design, database migrations, and a React UI with data visualizations. You will build reliable integrations with ad platforms and modernize a Flask + React application used by hundreds of customers.

You will work closely with scientists and data engineers to translate statistical outputs into actionable product experiences. Expect collaboration, AI-assisted development, and on-call responsibilities.

Qualifications

• 5–10+ years of experience building and shipping production web applications and APIs.
• Proficiency in Python and React; Flask/SQLAlchemy a plus.
• Experience with large legacy codebases and pragmatic refactoring decisions.
• Comfort with cloud-native environments (GCP preferred).
• Experience with MySQL or PostgreSQL and data-heavy apps.
• Track record of using AI tools (Claude, Cursor, Copilot).
• Strong product sense and excellent communication.

Responsibilities

• Own features end-to-end from API design to React UI and monitoring.
• Integrate with third-party ad platforms (Meta, Google, TikTok).
• Modernize a Flask + React app serving hundreds of customers.
• Design data-rich UIs: charts and dashboards for marketing insights.
• Collaborate with scientists and data engineers to translate outputs into product experiences.
• Leverage AI tools to accelerate delivery and exploration.
• Participate in on-call rotation and maintain system health.
• Review code and uphold quality, clarity, and maintainability.

Skills

Full stack

Python

React

API design

SQLAlchemy

Flask

Cloud (GCP)

MySQL/PostgreSQL

AI tools

Communication

Product sense

Tools

Flask

SQLAlchemy

Copilot

Claude

Cursor

Git

Job description

Responsibilities

• Own features end-to-end: from API design and database migrations through React UI and data visualization, all the way to monitoring and on-call support
• Build and harden integrations with third-party ad platforms (Meta, Google, TikTok) — design for reliability across APIs you don’t control
• Evolve and modernize a production Flask + React application that serves hundreds of customers — improve architecture incrementally while shipping continuously
• Design and build data-rich UIs: charts, dashboards, and interactive tools that help marketers understand complex experimental results
• Collaborate closely with scientists and data engineers to translate statistical outputs into product experiences customers can act on
• Use AI development tools as part of your daily workflow to accelerate delivery, explore solutions, and raise the ceiling on what you can ship
• Participate in on-call rotation and own the operational health of the systems you build
• Review code across the team and help set the bar for quality, clarity, and maintainability

Requirements

• 5–10+ years of experience building and shipping production web applications and APIs
• Strong across the full stack: you can build a well-structured API endpoint, write a database migration, and implement the frontend that consumes it
• Proficiency in Python and React (or strong equivalents with willingness to ramp); experience with Flask, SQLAlchemy, or similar frameworks is a plus
• Experience working in and improving large, established codebases — you’ve navigated legacy systems, made pragmatic tradeoffs between refactoring and shipping, and left things better than you found them
• Comfort with cloud-native environments (GCP preferred): you understand how to deploy, monitor, and operate services in production
• Experience with relational databases (MySQL/PostgreSQL) and data-heavy applications
• Track record of working effectively with AI development tools (Claude, Cursor, Copilot, or similar) — you’ve integrated them into your workflow and can articulate how they change the way you build software
• Strong product sense: you think about what customers need, not just what the ticket says
• Excellent communication skills — you can explain technical tradeoffs clearly and work effectively with scientists, product managers, and other engineers.