Your mission As a Senior Freelance Backend Engineer at mula, you will play a key role in strengthening our backend infrastructure while working flexibly on a part-time basis. Our mission is to become the most digitally integrated B2B Merchandise Platform globally. You’ll focus on impactful backend topics — from shop solutions to integrations — and help us implement advanced technological concepts that scale. Your role Collaborate with our Tech Unit, responsible for all digital and technical touchpoints. Contribute to shaping our backend infrastructure and integration portfolio. Act as an expert in APIs, plugins, automations, and integrations. Provide your senior expertise to guide architectural and strategic decisions while enjoying the flexibility of a freelance setup. Your tasks Shape our backend architecture and introduce new components where needed. Maintain and extend backend services built in Python (Django). Improve existing integrations and implement new automations (HR, CRM, and beyond). Lead the development of client-facing APIs and keep documentation up to date. Work on diverse challenges: shop solutions, payment (Stripe), integrations, automations, plugins, SSO, Adobe automations, and both internal & public APIs. Collaborate closely with product, design, and support teams to solve real-world business problems. Accelerate us on our path toward a clean, fast, and reliable platform experience. Share your knowledge with our team, mentoring where relevant, and contributing with a pragmatic, senior mindset. Your profile Based in Europe (CET) or able to work during European business hours Senior-level experience (4 years) with Python and Django. Comfortable with lean and agile product development in fast-moving environments. Solid knowledge of REST and SOAP API design. Nice to have: exposure to serverless architectures, AWS services (Lambda, SQS, SNS, DynamoDB), or infrastructure-as-code (Terraform, CloudFormation). Bonus if you’ve worked with: PostgreSQL, Redis, RabbitMQ, Kubernetes, AWS, EKS, Node.js, Next.js, JavaScript, React, Docker. Strong communicator who documents well and shares knowledge openly. Independent, reliable, and able to manage your own workload within part-time availability. Fluent in English, both spoken and written. Nice to have Broader experience with Django and other Python frameworks. Knowledge of frontend technologies (React, ES6, JavaScript). AWS certifications. Cybersecurity awareness. Why us? Flexible part-time engagement tailored to your availability. Contribute meaningfully without a full-time commitment. Work remotely with a collaborative, international team. Focus on impactful backend and integration projects where your expertise makes the difference. About us mula. is a fast-growing HR- and Tech Startup integrating and streamlining the design, purchase, storage and distribution of promotional goods in the most efficient way possible. We are building a powerful digital platform with unique capabilities to revolutionise and emphasise the importance of employer branding.