Full‑Stack Engineer II/Sr (React + Python)

Full‑Stack Engineer II/Sr Job Description

Why Nuclearn.ai

Nuclearn.ai builds AI-powered software for the nuclear and utility industries—tools that keep critical infrastructure reliable, efficient, and safe. Our software integrates AI-driven workflow, documentation, and research automation, and is already used at 60+ nuclear reactors across North America. You'll ship production code operators and engineers rely on every day.

We're growing quickly, expanding our team and our Phoenix HQ. The work is consequential: what you build helps real plants run safer and smarter.

Eligibility: U.S. citizenship or permanent residency (green card) is required due to DOE export compliance.

What You'll Do

• You'll own features end‑to‑end across a modern Python/React stack, with a heavy dose of reliability, data plumbing, and “meet the enterprise where it is” integration work.
• Ship production features across React (frontend) and FastAPI (backend) that power our products (e.g., CAP AI, AtomAssist).
• Design and evolve APIs and Postgres schemas for performance, correctness, and auditability (migrations, indexing/partitioning, background data corrections).
• Containerize and deploy services with Docker/Podman and Kubernetes; help tune queues/workers (Redis, RabbitMQ, Celery) for throughput, reliability and idempotency.
• Make data usable: build ingestion pipelines that prefer tabular sources (CSV/Excel/JSON) but gracefully handle the “we only have PDFs” reality - minimizing OCR, adding validation, and failing safely.
• Integrate with customer systems common in the industry (e.g., Maximo, DevonWay, Microsoft 365/Teams/OneNote).
• Own reliability: reduce noise and fix root causes identified across Sentry and Netdata; add observability, back‑pressure, retries, and circuit breakers so we never lose a record.
• Collaborate with customers: join (lightweight) customer calls with utilities to understand constraints, scope integrations, and demo new capabilities.
• Reality of the role: You'll bounce between product code, schema work, a gnarly data import, a Sentry investigation, and a customer demo environment - often in the same week.

Examples of problems you might own in your first 90 days

• Build a DevonWay → CAP AI connector that ingests event data in tabular form, validates against our schemas, and supports safe reprocessing.
• Add a “simulate, then apply” workflow for CAP automations (human‑in‑the‑loop gates, dry‑run diffs, full audit trails, easy rollbacks).
• Cut a noisy Sentry class of errors by 30% by hardening a Celery task (idempotent writes, retry policy, dead‑letter queue).
• Implement license entitlements & usage reporting for a fleet customer renewal (clean server‑side enforcement plus UI visibility).
• Deliver a small Teams/OneNote POC to integrate new data streams into AtomAssist.

What Makes You a Great Fit

• Degree in CS or related field—or equivalent practical experience.
• You've shipped production React + FastAPI and can contribute independently within ~6 weeks.
• You care about correctness and safety: typed APIs, schema migrations with backfills, idempotent jobs, and tests that catch the sharp edges.
• You're comfortable with customer‑facing engineering (a quick demo, a clarifying question, a pragmatic workaround).
• Clear, direct communicator; kind reviewer; steady under pressure.

Nice To Have (not Required)

• AI/ML or data‑pipeline experience (prompting, retrieval, feature stores, vector search).
• Prior startup experience.
• Exposure to nuclear/utility or other safety‑critical domains (aviation, med‑device, rail, etc.).

The stack you'll shepherd

• Frontend: React, JavaScript, HTML/CSS
• Backend: Python (FastAPI)
• Data/Infra: PostgreSQL, SQLite; Redis, RabbitMQ, Celery
• DevOps: Docker/Podman, Kubernetes; GitHub Actions
• Observability: Sentry, Netdata (and the dashboards you help us build)
• Quality: PyTest, Cypress
• Collab: Git/GitHub

Impact You'll Have (near-term roadmap)

• CAP AI “toward 100% automation” : design safe guardrails (review gates, audit, simulation modes).
• Data connectors : unstructured PDFs, structured feeds; resilient syncs with Maximo/DevonWay; M365 integrations.
• Performance & reliability : fewer flakes, faster jobs, clearer dashboards, calmer alerts.

Compensation & Benefits

• Base salary: $135k - $1172k (Engineer II), $165k - $201k (Engineer Sr)
• Equity: 0.03% - 0.15% (Engineer II), 0.04% - 0.20% (Engineer Sr), in the form of stock options
• Benefits: Unlimited PTO, health/dental/vision insurance

Work Model & Schedule

• Full-time, salaried
• Mon–Fri hybrid (Wed remote); expectation is ≥80% in-office (Phoenix HQ)

How We Hire (fast, respectful, practical)

1. 20-min intro with the founder/hiring manager to trade context and assess mutual fit
2. Practical work sample (60–90 min; a real task in our stack)
3. Team meet + peer programming (system design + collaboration)
   We aim to move from first chat to decision quickly.