Senior Full Stack Engineer (AWS Microservices & Integrations)

Location: Bristol, UK — predominantly in-house

Employment: Full-Time, Permanent

Salary: £65,000 – £80,000+

Experience: 4+ years operating on AWS with meaningful DevOps ownership

If you think you are the right match for the following opportunity, apply after reading the complete description.

About Us

Narwhal Labs is a fast-growing tech start-up based in Bristol. We are building an AI communications platform at scale, and our engineering team is central to everything we do.

We are looking for a Senior Fullstack Engineer who thrives on ownership, enjoys building reliable systems and wants to help shape the architecture of a product used by real customers in production.

The Role:

We are looking for a Senior Fullstack Engineer to own our microservices platform on AWS. You will build reliable, multi-tenant services and a first-class integration layer spanning messaging, outreach, CRM, billing, analytics and payment systems that powers a SaaS product at scale.

This is an office-based role and candidates must be located in or within commutable distance of Bristol.

Responsibilities:

• Design and build microservices behind API Gateway (REST/HTTP), running on Lambda and containerised workloads on EC2/Fargate
• Model multi-tenant data across DynamoDB and RDS (PostgreSQL), using S3 for object storage and KMS for secrets and encryption
• Build and maintain an integrations layer including OAuth/API-key onboarding, webhook ingestion with idempotency, retries and DLQs, rate-limit mediation, circuit breakers and versioned connector contracts
• Integrate with third-party platforms and payment systems, ensuring secure, reliable and scalable flows for transactions, billing and data exchange
• Design and implement event-driven architecture by publishing and consuming domain events via SQS, SNS and EventBridge, using Step Functions where orchestration is needed
• Maintain observability and reliability through structured logging, metrics and alerts with CloudWatch, trace propagation and error budgets
• Apply security best practices including least-privilege IAM, secret rotation, per-tenant isolation and audit logs
• Define infrastructure as code using AWS SAM and ship via GitHub Actions with automated tests and canary/blue-green deployments
• Define clear API contracts with frontend and AI services, and document runbooks and postmortems

Requirements:

• 4+ years operating on AWS with meaningful DevOps ownership — you have shipped and run production systems
• Hands-on experience with Lambda, EC2/Fargate, API Gateway, S3, DynamoDB, RDS (PostgreSQL), SQS/SNS/EventBridge, CloudWatch and KMS
• Infrastructure as code experience with AWS SAM including templates, pipelines and parameterised stacks
• CI/CD experience with GitHub Actions and automated testing using tools such as Jest/Vitest, Postman/Newman or Pact
• Strong xwzovoh backend development in Node.js/TypeScript (Go or Python also welcome) and solid API design skills across REST, with GraphQL a plus
• Strong data modelling skills including NoSQL vs relational trade-offs, partitioning, indexing and migration strategies
• Proven experience building and consuming webhook-heavy third-party integrations with idempotency and signature verification
• Experience integrating with payment gateways such as Stripe, Adyen or Braintree and handling PCI/DSS-compliant transaction flows

Nice to have:

• Event choreography with Step Functions, schema registries and outbox patterns
• OpenTelemetry/X-Ray tracing and cost and performance tuning for Lambda and RDS
• Experience with Cognito/OIDC, RBAC/ABAC and multi-tenant isolation patterns
• Familiarity with real-time delivery via WebSockets or SSE and streaming responses
• Background in building connector SDKs or integration marketplaces