Senior Full-Stack Engineer / Junior CTO gesucht für NotarNow

Senior Full-Stack Engineer (AI, Document Processing) — German-speaking

About NotarNow

NotarNow is building a digital notary platform that streamlines German document and notarization workflows. We combine a modern web product (Next.js/TypeScript) with a FastAPI backend deployed on AWS and ship AI-powered document understanding, search, and real-time collaboration.

We’re one of Europe’s fastest-growing bootstrapped legal-tech startups. We hit €1.5M ARR in under two years and are scaling fast. Our products run real high-stakes professional workflows, process real documents, and are used by 1,000+ legal professionals.

Now we’re adding a senior engineer to the core product team. This role is for an engineer who can ship end-to-end, own production outcomes, and move fast without lowering the bar. You’ll be part of a small, talented, highly driven dev-team all of whom bring the same level of ownership, curiosity, and ambition you value yourself. No passengers. No layers. High trust, high ownership, high standards.


You might be a great fit if you

Have 5+ years building and shipping production web systems and can independently deliver end-to-end features.
Are strong in TypeScript/React/Next.js and comfortable with complex client state (RTK Query caching/invalidation, auth/session flows, real-time updates).
Are strong in Python/FastAPI with async I/O, API design, and disciplined data modeling (Pydantic, enums, typed interfaces).
Have shipped systems on AWS and understand queues, retries, idempotency, and failure modes in distributed systems.
Can debug production issues quickly (logs, metrics, traces), write fixes safely, and communicate clearly.
Have a product mindset: you enjoy talking to users and see “product” as part of the job.
Speak German fluently (you can run user calls, write clear German messages, and work with German legal/administrative terminology). English is used in code and many docs.

Strong signals (nice to have)

Stripe subscription lifecycle experience (schedules, proration, consolidated subscriptions, webhooks).
OCR/document extraction pipelines and working with imperfect inputs (PDFs, scans, tables/forms).
Building agentic systems: tool design, guardrails, evals, prompt versioning, cost/perf tradeoffs.
Comfort owning a service: operational runbooks, alerts, and “never fail the same way twice” postmortems.
Experience with MongoDB Atlas Search and vector search in production.

How we work (and what we value)

High ownership: you ship outcomes, not tickets.
Type safety and correctness: Pydantic models, enums over strings, explicit error handling, tests on critical paths.
Move fast with discipline: small PRs, measurable changes, and production awareness.
Thoughtful use of AI tools: we use AI daily to accelerate; you must be able to verify, test, and own the final result.

• Frontend
• Backend
• Full stack
• Engineer

Du bist gut mit...

• Dinge vorantreiben und erledigen

Du hast bereits...

• Vollzeitbeschäftigte geführt

What you’ll do

Own end-to-end features across our Next.js frontend and FastAPI backend—design, build, test, ship, and monitor.
Harden and evolve our document processing pipeline: uploads → S3 → async processing (Azure Document Intelligence / Textract / multimodal) → DB persistence → semantic search (vector stores).
Improve reliability and correctness of event-driven processing (SQS → Lambda handlers), idempotency, retries, DLQs, and observability.
Build and maintain real-time UX (WebSocket events + SSE streaming) for long-running AI and document workflows.
Work in the billing system (Stripe subscriptions, consolidated subscriptions, plan switches, schedules, proration) and make changes safely via tests + rollout strategy.
Collaborate directly with users/stakeholders (often in German) to understand workflows and iterate quickly.
Raise engineering standards through crisp PRs, tests, refactors, and documentation.

Tech stack (what you’ll touch)

Frontend: Next.js 15, TypeScript, Redux Toolkit + RTK Query, MUI + Tailwind, NextAuth (Cognito), WebSockets, SSE.
Backend: FastAPI (async), MongoDB (Motor), Pydantic models, repository/service patterns.
AWS: ECS (containers), Lambda, S3, SQS (+ DLQ), API Gateway / NLB, Secrets Manager.
AI: multi-provider AI module, OpenAI Agents SDK (tool use, streaming, context management), extraction into typed Pydantic models, evaluation/quality workflows.
Testing: pytest (incl. integration/real-PDF suites), Jest/RTL, Playwright.

First 30 / 60 / 90 days (success looks like)

30 days: run the stack locally; ship a few small production changes; understand our critical flows (billing, document processing, SQS/Lambda tasks, real-time streaming).
60 days: own a medium-sized end-to-end feature; improve reliability or testing in a critical area (billing or document processing); be comfortable taking primary responsibility for a production incident in your area.
90 days: lead a high-impact project (e.g., quality improvements for a real PDF workflow, billing lifecycle hardening, or real-time reliability) and set a sustainable standard others can follow.

Remote (time zone overlap with Central Europe preferred).
German-speaking required.
Compensation, engagement model, and ESOP depend on seniority and scope; we hire for impact and long-term ownership.
Start: ASAP. Latest: 01.04.2026.
Apply by emailing: [email protected]

Unsere Vision ist es, das europaweit führende KI-Softwareunternehmen für Notariate zu werden – bootstrapped, produktgetrieben und nah an der Praxis.

KI-Software für Notariate: KI-gestützte Dokumentenverarbeitung, Agenten, strukturierte Datenerfassung, Workflow-Tools und Echtzeit-Kollaboration.