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Handshake is a career platform powering 25 million job seekers, 1 million+ employers, and 1,600 educational institutions. In 2025, the company launched Handshake AI, a rapidly growing data business supporting frontier AI labs with human data for model training and evaluation. The business has scaled from $0 to ~$1B run rate in under a year.
You will join the Forward Deployed Engineering (FDE) team in Sofia as a senior engineer. FDEs are software engineers who work much closer to customers than typical product engineers—you find problems, decide if they are engineering problems, scope solutions, and either build them yourself or guide product teams through implementation.
As a senior member, your judgment will shape how the team approaches critical partnerships and set standards for forward-deployed work from Sofia. Due to timezone differences, this role leans more toward traditional software engineering than on-site customer work; most real-time customer contact is handled by the San Francisco team, with engagement primarily over Zoom and async communication.
Key responsibilities:
- Own design, architecture, and delivery of tailored, production-grade solutions for complex, high-impact customer needs with no existing playbook
- Identify problems early—fragile pipelines, missing quality checks, systems that won't scale—and make the case for solutions
- Build tools and internal systems the wider team needs but hasn't had time to create
- Own tradeoff conversations: weigh engineering effort against business outcomes weekly
- Turn one-off fixes into reusable infrastructure and repeatable deployment patterns
- Make key architectural decisions around reliability, scalability, and security; create playbooks for efficient scaling
- Mentor and uplevel other engineers through code reviews, architectural guidance, and best practices
The pace is demanding. FDEs own deliverables customers are waiting on and projects with meaningful revenue. You will touch more systems, more customers, and make more decisions than a typical product role. You will work alongside staff-level engineers and, on some projects, directly with founders. You will participate in spending and build-vs-buy decisions.
Requirements:
- 6+ years of professional software engineering experience
- Strong proficiency with ReactJS and TypeScript, with high standards for code quality, usability, and accessibility
- Deep understanding of relational databases (e.g., PostgreSQL), data modeling, and system design
- Experience with cloud infrastructure (AWS, GCP), deployment pipelines, and production operations at scale
- Demonstrated ability to lead technical projects end-to-end in ambiguous environments with shifting requirements
- Track record of mentoring engineers and raising engineering practice standards within a team
- Excellent communication and stakeholder management; you communicate progress, complications, and timelines so course corrections happen early
- Innate curiosity and willingness to ask hard questions until you have the context needed
- Heavy, critical use of AI as a tool you understand and can verify, not a substitute for your own problem understanding
- Self-directed: you create work rather than wait for it
- Judgment to recognize when a problem is not an engineering problem
Desired (extra credit):
- Experience architecting and delivering production systems for LLMs or other AI-powered products in real-world, customer-facing environments
- Background building or contributing to component libraries, design systems, or reusable deployment frameworks
- Proven experience with performance optimization and scaling of full-stack applications under real-world constraints and high-traffic conditions
