THE ROLE (BACKEND / AI SYSTEMS ENGINEER)You'll build the backend systems that power Spellbook's product experiences, including both traditional software services and AI-driven workflows. This is a hands-on, high-ownership role for an engineer who cares about product outcomes and understands what requires scale vs what does not, and can turn ambiguity into robust systems that lawyers trust.
THE TECH STACKNode.js, TypeScript, Express, tRPC, MongoDB, Docker, AWS, CDK, LLM providers (OpenAI, Anthropic, and others)
RESPONSIBILITIES- Build and scale backend systems that support core product functionality across Spellbook (Reviews, Chat, Library, and more).
- Design low-latency, high-reliability search, inference, and orchestration layers for AI features
- Build and operate RAG retrieval at scale with production-grade performance optimization and permissions-correct data isolation.
- Own core platform concerns for AI: rate limiting, retries, consistency, fallbacks, safe degradation
- Partner closely with Product and Design to make good tradeoffs between latency, accuracy, UX, and reliability.
- Use modern development workflows, including agent-assisted coding, to accelerate delivery while maintaining rigorous review, testing, and security standards.
- Participate in on-call and incident response as needed, and improve feature reliability in the process
QUALIFICATIONS- You have 5+ years of experience building backend systems in production.
- You have strong fundamentals in backend engineering and distributed systems: APIs, data modeling, concurrency, queues, AI inference
- You have strong NoSQL (ideally MongoDB) data modeling and performance tuning: schema design/denormalization tradeoffs, indexing strategy, query optimization, and profiling/diagnosing bottlenecks in production.
- You can take an ambiguous, high-impact problem from "we should do something here" to a clear plan and shipped outcome.
- You have strong communication skills. You can write and explain technical decisions clearly to engineers and non-engineers.
- You are a self-starter and problem-solver motivated by curiosity and a desire to help others succeed, encouraged by continuous improvement.
- You are pragmatic and understand that not everything we ship needs to scale, but know where to draw the line
- You are a team player who is motivated to help Spellbook succeed. When things break you are eager and able to help fix them. You think of and implement ways to help and improve the work of the team as a whole.
NICE TO HAVES- Experience building LLM-powered systems in production, including prompt iteration, tool/function calling, retrieval patterns, and agent orchestration.
- Experience operating high-scale retrieval systems (vector + lexical search) and measuring/tuning retrieval quality and latency in production.
- Experience building evaluation frameworks (quality metrics, dataset curation, regression testing).
- Experience with AWS CDK and operating production services in AWS.
WHY JOIN SPELLBOOK?- Embrace autonomy and accountability in a flexible, remote work environment; we focus on outcomes and empower you to determine how to get the job done
- Access our company-paid group benefits for you and your family, with $1,000 towards mental health support
- Disconnect during our holiday closure and take advantage of our generous time off policies throughout the year
- Enjoy monthly paid meals, an annual wellness allowance to support your well-being and parental leave top-ups as your family grows
- Secure your stake in our success; you'll receive competitive stock option grants as a pivotal early employee
WHY JOIN SPELLBOOK?- Embrace autonomy and accountability in a flexible work environment; we focus on outcomes and empower you to determine how to get the job done
- Access our company-paid group benefits for you and your family, with $1,000 towards mental health support
- Disconnect during our holiday closure and take advantage of our generous time off policies throughout the year
- Enjoy monthly paid meals, an annual wellness allowance to support your well-being and parental leave top-ups as your family grows
- Secure your stake in our success; you'll receive competitive stock option grants as a pivotal early employee