Backend Engineer

About Mem0 We're building the memory layer for AI agents: long-term memory that lets AI remember conversations, learn from interactions, and build real context over time, the difference between a chatbot and something that actually knows you. We're already powering millions of AI interactions for enterprise customers and a fast-growing open-source community (160k+ developers and counting). We're backed by top-tier investors through a $24M Series A & Seed, early enough that the systems you build now become the foundation everything else is built on. This role owns the backend behind that platform. You'll design clean REST APIs, model data across relational and graph stores, and operate services in production. When customers hit issues, you'll chase them down to root cause, ship fixes, and harden the system, working closely with frontend and research to deliver fast, reliable features. You'll design the core systems, decide how they're built, and stay with them through production. Our users are developers integrating us into their own agents, which means the APIs you design are the product as far as they're concerned. This role reports directly to Deshraj Yadav, our Co-founder and CTO, and works closely with the engineering team in San Francisco. What you'll do Design & ship REST APIs: Define contracts, versioning, auth, rate limits; write migrations and docs. Model data & schemas: Relational (Postgres) and graph (e.g. Neo4j); enforce integrity and performance. Debug customer issues end to end: Trace with logs, metrics and traces, reproduce, fix, and write preventative guardrails. Optimize performance: Tune slow SQL with EXPLAIN/ANALYZE, indexes, partitioning, pagination, and caching (e.g. Redis). Build services in Python: Async where it helps (FastAPI, Django/DRF, Flask), background jobs, queues, schedulers. Operate in the cloud: Containerize with Docker, deploy on Kubernetes (EKS), and use AWS primitives (EC2, RDS/Aurora, S3, IAM). Instrument everything: Custom metrics, structured logging, tracing; set SLOs and alerts (CloudWatch/Prometheus/OpenTelemetry). Collaborate & ship: Work with frontend and research to scope APIs and deliver features to production. Minimum qualifications 5+ years building backend systems and shipping REST APIs to production. Strong Python fundamentals; experience with async programming and a major web framework (FastAPI/Django/Flask). Solid data modeling and SQL skills; hands-on with query tuning and performance debugging in Postgres/MySQL. Experience with graph databases (e.g. Neo4j or Amazon Neptune) and the data modeling trade-offs that come with them. Comfortable running services on AWS with Docker and Kubernetes. Demonstrated root-cause analysis and ownership from incident to prevention. Clear communicator and effective collaborator with frontend, research, and customers. Nice to have GraphQL/gRPC; event-driven systems (SNS/SQS/Kafka) and background workers (Celery/RQ). Caching, rate limiting, multi-tenancy, and feature-flag strategies. Security & privacy best practices (PII handling, secrets management). Deep observability experience (OpenTelemetry, SLO-based alerting). Prior work with search/retrieval or memory systems. On-call experience and running blameless postmortems. Prior time at an early-stage startup. Series A, YC, or founding engineer experience tells us a lot. Our culture Velocity with craftsmanship: We build for the long term, not just shipping features. We move fast but never sacrifice reliability or thoughtful design. Every system needs to be fast, reliable, and elegant. Extreme ownership: Everyone at Mem0 is a builder-owner. If you spot a problem or opportunity, you have the agency to fix it. Titles are light; impact is heavy. High bar, high trust: We hire for talent and potential, then give people room to run. Code is reviewed, ideas are challenged, and wins are celebrated, always with respect and curiosity. Data-driven, not ego-driven: The best solution wins, whether it comes from a founder or an engineer who joined yesterday. We let results and metrics guide our decisions.