Freelance Backend Engineer

Freelance Senior Backend Engineer – TypeScript / AWS Serverless

Location: Amsterdam, Netherlands (Hybrid – 1 day onsite per week)

Contract: 12 months

Hours: 35 billable hours per week

Rate: Competitive, dependent on experience

Start: ASAP

The Opportunity

We're working directly with an established, bank-backed Dutch fintech that's transforming how businesses access finance.

They're looking for experienced Freelance Senior Backend Engineers to join their engineering team, taking ownership of the design and development of scalable, cloud-native backend systems.

This is a genuinely hands-on engineering opportunity, where you'll have input into architectural decisions and work directly with the people building the products.

The focus is approximately 90% backend and 10% frontend.

What You'll Be Doing

• Designing, developing and maintaining scalable backend services using TypeScript and Node.js.
• Building serverless, event-driven applications on AWS.
• Designing APIs, integrations and complex business workflows.
• Working with DynamoDB, including data modelling and access patterns.
• Making architectural decisions around scalability, reliability, performance and maintainability.
• Taking ownership of solutions from initial design through to production.
• Collaborating directly with engineers and business stakeholders.

What We're Looking For

Essential experience:

• Strong commercial experience with TypeScript and Node.js .
• Hands-on production experience with AWS Serverless , particularly Lambda.
• Practical experience with SNS, SQS and EventBridge .
• Strong knowledge of DynamoDB , including single-table design and modelling relationships between entities.
• Experience designing and developing REST APIs, integrations and event-driven systems.
• Strong understanding of system design, asynchronous processing, caching and distributed architectures.
• Ability to explain technical decisions, trade-offs and personal contributions to previous projects.

Beneficial experience:

• React
• Terraform / AWS CDK
• Python
• Financial services or fintech environments

The Type of Engineer We're Looking For

We're particularly interested in engineers who have personally designed AND built meaningful backend systems at scale .

Someone who can take a business problem, understand the requirements, propose an appropriate architecture and implement the solution independently.

This isn't a purely architectural position, nor is it simply a ticket-driven development role. You'll need to be equally comfortable discussing system design and writing production-quality code.

Why Consider This Opportunity?

• 12-month freelance assignment with an established fintech.
• Work directly within the end client's engineering team.
• Genuine ownership of architecture and implementation.
• Modern TypeScript and AWS Serverless environment.
• Hybrid working with approximately one day per week in Amsterdam.
• Competitive freelance rates reflecting technical expertise.
• Potential for multiple freelance engineers to join.

Interested?

If you're a senior backend engineer with strong TypeScript and AWS Serverless experience who enjoys taking ownership of complex technical challenges, we'd be interested in hearing from you.

Apply within.