Job Description

Senior Backend Engineer -- AWS Microservices & Integrations

Bristol, BS1, UK

Salary up to 80k dependent on experience

What We Do

Narwhal.AI is a communication and sales platform built as a bespoke, agentic AI solution that orchestrates end-to-end campaigns across phone, SMS, WhatsApp, and email. It automates outreach, follow-ups, and scheduling while personalising messages to each lead, then adapts in real time based on responses and engagement. The agent can qualify prospects, route hot leads to humans, and keeps conversations consistent. Teams get unified analytics- open/click rates, call outcomes, reply intent, and pipeline movement-with controls for A/B testing and compliance. Plug it into your CRM or workflows, and Narwhal.AI acts like an always-on SDR that scales targeted conversations without sacrificing the human touch.

Job Overview

You will own our microservices platform on AWS. Build reliable, multi?tenant services and a first?class integrations layer (messaging, outreach, CRM/billing, analytics, and payment systems) that powers a SaaS product at scale.

We are therefore looking for someone who has designed, built, and operated production systems at scale in AWS, ideally in a SaaS or integration?heavy environment. You should be comfortable owning a service end?to?end -- from infrastructure definition through deployment pipelines to live operations -- and confident integrating with external APIs, payment gateways, and event?driven workflows.

What you'll do

Design & build microservices behind API Gateway (REST/HTTP), running on Lambda and/or containerized workloads on EC2/Fargate. Model multi?tenant data across DynamoDB and RDS (PostgreSQL), using S3 for object storage and KMS for secrets/encryption. Integrations layer: OAuth/API?key onboarding, webhook ingestion (idempotency, retries, DLQs), rate?limit mediation, circuit breakers, and versioned connector contracts. Integrate with 3rd?party platforms and payment systems, ensuring secure, reliable, and scalable flows for transactions, billing, and data exchange. Event?driven architecture: Publish/consume domain events via SQS/SNS/EventBridge; use Step Functions where orchestration helps. Observability & reliability: Structured logging, metrics, and alerts with CloudWatch; trace propagation; error budgets and SLOs. Security by default: Least?privilege IAM, secret rotation, per?tenant isolation, audit logs. IaC & CI/CD: Define everything in AWS SAM, ship via GitHub Actions with automated tests, canary/blue?green where appropriate. Collaboration: Define crisp API contracts with Frontend & AI services; document runbooks and postmortems.

Must?haves

4+ years operating on AWS with meaningful DevOps ownership (you've shipped and run production systems). Hands?on with: Lambda, EC2/Fargate, API Gateway, S3, DynamoDB, RDS (Postgres), SQS/SNS/EventBridge, CloudWatch, KMS. Infrastructure as Code with AWS SAM (templates, pipelines, parameterized/staged stacks). CI/CD with GitHub Actions (workflows, artifacts, environment gates) and automated testing (unit/integration/contract; e.g., Jest/Vitest, Postman/Newman, Pact). Strong backend development in Node.js/TypeScript (Go or Python also welcome) and API design (REST; GraphQL a plus). Data modeling chops (NoSQL vs relational trade?offs, partitioning/indices, migration strategies). Proven experience building/consuming webhook?heavy 3rd?party integrations with idempotency and signature verification. Experience integrating with payment gateways (e.g., Stripe, Adyen, 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; cost/perf tuning for Lambda and RDS. Auth: Cognito/OIDC, RBAC/ABAC, multi?tenant isolation patterns. Experience with real?time delivery (WebSockets/SSE) and streaming responses. Background in building connector SDKs or marketplaces.

We offer

'Life leave' day to be taken when it suits you. Enhanced company pension contributions to match employee contributions (5%). 25 days of annual leave plus bank holidays (33 total). The option to join private medical cash plans for everyday health needs.
Job Type: Full-time

Pay: Up to 80,000.00 per year

Work Location: In person