Senior Software Engineer (Full Stack)

About the role

Senior Software Engineer (Full Stack) Full-time (40 hours per week), Remote

About the Company You will be joining an early-stage, AI-native German start-up building the digital infrastructure for grant funding. Its platform combines AI-supported research, matching and application drafting with expert review, so that non-profits and public organisations can spend their energy on their projects instead of on funding logic, forms and admin. The engineering team is small and the product already has real customer demand, so this hire will shape how both the product and the engineering function are built from here.

The Role As a Senior Software Engineer (Full Stack), you will own product and technical problems end-to-end, from the first conversation with the grant team through to production, across the frontend, backend, infrastructure and the AI pipeline at the core of the platform. This is one of the company’s first engineering hires: not everything is defined yet, and that is intentional. When you see a better solution, you are expected to build it, not wait for a ticket.

You will work directly with the founders and closely with the grant-writing team, with no designers or product managers in between. This role suits a senior engineer who has done this before in a start-up or scale-up: someone who can take an unclear business problem, turn it into a plan, ship a first version quickly, and explain the trade-offs clearly to non-technical colleagues.

Key Responsibilities

- Own features end-to-end, including the user interface, from discovery with the grant team through to production

- Turn ambiguous business problems into clear technical plans, ship a first version quickly, then iterate

- Advance the AI pipeline through prompt engineering, context management, cost control and a multi-provider setup (AWS Bedrock, Anthropic, OpenAI)

- Build and own the AI evaluation practice: prompt quality, model selection and regression detection

- Operate, monitor and debug the live production environment (Sentry, CloudWatch, Postgres performance)

- Make architecture decisions and shape code quality, engineering standards and the technical roadmap

- Build interfaces with a usability-first mindset so the product genuinely works for grant writers

- Shorten the time from starting a new project to a finished, submitted application through features, reliability and automation

Ideal Candidate

- 2+ years working in a senior engineering role (not only total experience), with a track record of owning products or major features end-to-end

- Start-up or scale-up experience: you have taken an unclear business problem with no real spec and shipped a working solution quickly

- Several years of professional experience with TypeScript and Node.js, plus solid Postgres depth (JSONB, query performance, migrations)

- Confident across the full stack: Next.js / React Query on the frontend, Express and BullMQ on the backend, AWS (ECS, RDS) for infrastructure