Senior Fullstack Engineer (m/f/d)

Freshflow

Freshflow

Posted on May 5, 2026

Senior Fullstack Engineer (m/f/d)

Freshflow — Senior Fullstack Engineer (m/f/d) | Berlin

About Freshflow

Freshflow is a B2B SaaS product that helps grocery stores optimize fresh-food ordering. We use machine learning to predict demand and generate order recommendations, reducing food waste and stock-outs. Our customers are some of the biggest retail chains across Germany and France.

The Role

You'll work primarily on the Python backend and secondarily on the Flutter mobile app. We are a small team and you will get exposure to every part of our product. This includes ingesting data from customers, processing it, integrating our AI services, and serving it to our customers via our app or into their external systems.

What You'll Work On

Backend
APIs: Building and maintaining the REST APIs that serve order recommendations to the mobile app and white-label partners, handle order submissions, and those that we use internally.
Partner integrations: Receiving data and routing finalized orders to supplier systems via different means. Building new integrations as we onboard retail chains.
Data delivery: Bridging the analytical layer and the mobile app — reading computed recommendations from the warehouse, denormalizing them, and writing them to an operational store the app can sync from.
Infrastructure: Provisioning and managing the cloud resources these services run on (compute, databases, messaging, secrets).
Mobile App
The primary focus for this role is our backend, but we need you to be able to also contribute to our Flutter mobile app when required. Topics here could include:
Working on the on-device recommendation adjustment engine and the sync protocol client-side.
Client-specific adjustments to the order flow.
Adjusting our app to make it ready for other device types (especially Android Mobile and/or MDE devices used by retail stores).

What We're Looking For

Strong Python experience. You'll write FastAPI services, Pydantic models, async code, and background workers.
Experience with PostgreSQL and at least one document database (Firestore, MongoDB, DynamoDB). You'll work with both daily.
Experience with REST API design. You'll build APIs that both internal UIs and external partners consume (versioning, auth, rate limiting, documentation).
Understanding of authentication and authorization patterns (OAuth 2.0, JWTs, role-based access control).
Understanding of multi-tenant data isolation (row-level security, path-based isolation, scoped tokens).
Experience with Flutter or strong willingness to work in Dart/Flutter. You don't need to be a Flutter expert, but you should be comfortable reading and contributing to a mobile codebase.
Experience building sync protocols or offline-first mobile apps.
Comfort moving between layers — backend one week, mobile the next, based on what needs doing.
Experience with GCP or equivalent cloud platform.
Nice to have
Experience with BigQuery or similar columnar warehouses.
Terraform or equivalent IaC experience.
Familiarity with async messaging patterns (queues, pub/sub, dead-letter handling, idempotency).
Exposure to B2B SaaS or the grocery/retail domain.

How We Work

Small team, high ownership, minimal process overhead.
Python backend, dbt for analytical data transformation, Flutter for mobile, Airflow for orchestration.
Everything on GCP: Cloud Run for compute, BigQuery for analytics, Firestore for operational data.
We are a small company and you need to be comfortable in an unstructured environment.

How to Apply

Applications for this role are handled exclusively through our Notion application form — please do not send applications by email.
Freshflow is proud to be an equal opportunity employer. We don't discriminate based on race or ethnic origin, color, language, national origin, disability, age, gender, gender identity, sex, sexual orientation, religion, beliefs, or political opinions.