Cloud-native software consultancy

Precision-built software
for ambitious businesses.

We design, build, and deploy scalable SaaS products, intelligent AI integrations, and robust cloud infrastructure — so your team can focus on what matters most.

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About

Built on expertise. Driven by precision.

Kestrel Stack is a specialist software consultancy. We work with UK startups, growing SMEs, and forward-thinking enterprise teams to deliver software that is genuinely fit for purpose — engineered to scale, designed to last, and shipped on time.

Our name reflects our approach: the kestrel is renowned for its ability to hold perfectly still while scanning for opportunity, then strike with total precision. That is exactly how we build software — thoughtful planning, decisive execution, no wasted motion.

Every engagement is led directly by a senior engineer. No hand-offs, no account managers, no diluted delivery. Just clear communication and high-quality code.

Services

What we build

From prototype to production, we cover the full stack — application code, cloud infrastructure, AI integrations, and the automation that ties it all together.

SaaS Development

Cloud-native SaaS applications built with Python and FastAPI. Designed for reliability, built for growth — from MVP to multi-tenant production platform.

  • Python
  • FastAPI
  • PostgreSQL
  • AWS Lambda

Cloud Infrastructure

Infrastructure as code with Terraform on AWS. Repeatable, auditable environments — from zero to production without configuration drift.

  • AWS
  • Terraform
  • IaC
  • eu-west-2

AI Applications

Practical AI integrations using Claude, OpenAI, and open-source LLMs. Intelligent agents, RAG pipelines, and workflow automation that deliver measurable business value.

  • Claude
  • OpenAI
  • LLM Agents
  • RAG

DevOps & CI/CD

Automated pipelines, containerised workloads, and production-grade deployments. GitHub Actions, Docker, and Kubernetes — built to ship fast and recover instantly.

  • GitHub Actions
  • Docker
  • Kubernetes
  • ECR
Projects

Recent work

A selection of projects across SaaS, infrastructure, and intelligent automation. Case studies published with client approval.

Multi-tenant analytics SaaS

End-to-end build of a cloud-native analytics platform for a UK fintech startup. FastAPI backend, React frontend, deployed to AWS Lambda and CloudFront.

FastAPIAWSTerraform

Intelligent document processing

LLM-powered pipeline for automated extraction and classification of unstructured contract data, reducing manual review time by over 80%.

ClaudePythonRAG

Zero-downtime AWS migration

Full infrastructure re-architecture from EC2 monolith to ECS-based microservices, with blue/green deployments and automated rollback via GitHub Actions.

AWS ECSTerraformGitHub Actions
Contact

Let's build something great

Have a project in mind? Tell us what you're working on and we'll respond within one business day.