Full Stack Engineer

Location: North West UK (remote/flexible considered)

Type: Full-time or part-time (flexible)

Formisimo is an award winning SaaS technology company based in Manchester. Using our market leading technology platform Zuko, we help online brands understand their website visitors and how they engage with online forms. We give them the insight they need to improve their online user experience, and help transform their businesses as a result.

We’re also building a new generation of AI-powered analytics and diagnostic tools, incorporating technologies like OpenAI and modern frontend infrastructure.

We’re looking for a pragmatic, product-minded Full Stack Engineer to help evolve and maintain the Zuko platform.

This is a high-impact role where you’ll take ownership of meaningful parts of the system (not just implement tickets). You’ll work closely with a fractional senior technical lead and senior management of the company, but day-to-day you’ll be expected to drive work forward independently.

This role is ideal for someone who:

• Enjoys solving real-world problems end-to-end
• Is comfortable navigating existing systems and improving them
• Doesn’t wait to be told what to do
  

Our platform includes:

• React frontend
• Ruby on Rails API layer
• Event ingestion pipeline (Node.js + AWS ECS)
• Real-time data processing using Kinesis, Lambda, Redis, and OpenSearch
• AWS-based infrastructure (CloudFront, S3, Aurora, etc.)

You’ll contribute across the stack - from UI improvements to backend performance and data pipeline reliability.

We’re also building new products using:

• Vercel
• OpenAI integrations
• Automation tooling (e.g. Skyvern, trigger.dev)

You’ll have the opportunity to work on these from an early stage and help shape how they evolve.

• Take ownership of features and systems from idea to production
• Improve and maintain our core platform and data pipeline
• Build new product features across frontend and backend
• Identify and fix issues proactively (performance, reliability, UX)
• Work with our fractional senior lead on architecture and technical direction
• Contribute to simplifying and strengthening the platform over time

• Solid experience as a full stack engineer (mid-level or above)
• Strong JavaScript/TypeScript experience (React ideally)
• Backend experience (Ruby, Node.js, or similar)
• Comfortable working with APIs, databases, and cloud infrastructure
• Experience with AWS or similar cloud platforms

• Ownership mentality - you take responsibility for outcomes, not just tasks
• Self-directed - you can figure things out without heavy guidance
• Pragmatic - you balance speed and quality effectively
• Curious - you ask “why” and look to improve things
• Comfortable working in a small, evolving team

• Experience with data pipelines or event-driven systems
• Familiarity with Redis, OpenSearch/Elasticsearch, or Kinesis
• Experience with AI/LLM integrations (e.g. OpenAI)
• Experience working with early-stage or scaling SaaS products

• Flexible working (full-time or part-time considered)
• Predominantly working from home with occasional-face to-face days
• Remote-friendly (UK-based preferred; North West ideal but not required)
• Small, collaborative team

As well as the opportunity to work for an exciting tech company we offer:

• Flexible working hours.
• Competitive salary dependent on experience.
• Monthly wellbeing stipend to spend on something that benefits your mental or bodily health.
• Autonomy, ownership and a flat management structure mean your opinions will be listened to and you’ll have a big impact from the start.
• Your ideas to be taken seriously and valued, and have your input directly affect the future of our company.
• To have the space and autonomy to manage your own workload and priorities, and be able to enact your ideas and improve on our current way of doing things.
• A high level of company transparency - company profit and loss, budgets and more are all shared in our open and honest working environment.
• A close-knit, focussed and productive team.
• Working with household name brands like Experian and Capital One as well as clients based across the world.
• All the incredible experiences of working at an agile technology company - dizzying highs, and buckle-down-lows, but never boring.

If this sounds like you then please send us your CV to jobs@formisimo.com, ideally with a few sentences about how you fit the role.

Sorry, no recruiters please.