Customer Success Engineer (CXE)

Job Description

CS Engineer
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Flint is building AI that gives every K-12 student a truly personalized learning path while giving teachers superpowers. As CS Engineer you will own the core systems that turn our models into classroom-ready experiences used by thousands of students every day. Your code will directly decide whether a struggling reader gets the right next problem or a teacher gets the insight that changes a lesson.

Performance Objectives
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* Ship production-grade AI inference and personalization services that serve 10k+ concurrent student sessions with \<200ms p95 latency within your first 90 days.
* Design and implement the data pipelines that ingest student interactions, generate embeddings, and feed our recommendation engine so teachers see real-time mastery maps.
* Reduce model-serving cost per student by 40% through quantization, caching, and efficient batching while maintaining pedagogical quality.
* Own end-to-end delivery of at least two high-impact features (adaptive practice, automated feedback, or teacher copilot) from prototype to 95%+ uptime in production.
* Establish observability, evaluation harnesses, and A/B infrastructure so we can measure learning-outcome lift, not just click-through.
* Mentor one junior engineer and document architecture decisions so the team can scale without you becoming a bottleneck.

Environment \& Resources
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You report directly to the CTO and work with a tight 8-person product-engineering team (ML, full-stack, design). Stack: Python, FastAPI, PyTorch, Postgres, Redis, AWS. You will have cloud budget, GPU access, and autonomy to choose tools that actually move student outcomes. Early-stage means you will sit in every product conversation and see your work in classrooms within weeks.

Essential Qualifications
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* Shipped production ML or high-scale backend systems that handled real user traffic and measurable business/learning metrics.
* Deep Python + systems skills (concurrency, caching, data modeling) and comfort owning services from laptop to production.
* Experience building or integrating recommendation, NLP, or generative systems with evaluation loops, not just notebooks.
* Track record of making pragmatic trade-offs under resource constraints typical of a seed-stage company.
* Genuine curiosity about how kids learn and willingness to sit in classrooms or talk to teachers to validate assumptions.

Role Selling Points
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* Direct line of sight from your commit to a student who finally "gets it."
* Green-field architecture decisions that will define the next decade of the product.
* Tiny team, huge ownership---your work is 10--20% of the entire platform.
* Mission that compounds: every improvement multiplies across thousands of classrooms.
* Compensation: $100-140k salary, Equity in the company, Health Benefits

If you want to write the code that actually changes how kids learn, send us a short note on the hardest system you've shipped and why it mattered. We read every application.