Senior Fullstack Software Engineer
Senior Fullstack Software Engineer

Senior Fullstack Software Engineer

Full-Time 36000 - 60000 ÂŁ / year (est.) No home office possible
Outsmart Insight

At a Glance

  • Tasks: Design, build, and maintain production systems that power Outsmart’s platform.
  • Company: Join a small, intellectually serious tech company focused on quality and reliability.
  • Benefits: Enjoy a hybrid working style with a supportive team and meaningful responsibilities.
  • Why this job: Make architectural decisions and improve mature systems with real impact.
  • Qualifications: 8-15 years of engineering experience, strong Python skills, and comfort with legacy code.
  • Other info: Collaborate directly with senior decision-makers in a dynamic environment.

The predicted salary is between 36000 - 60000 ÂŁ per year.

The pitch. It’s a serious engineering role with a great team – and meaningful responsibility. This is not a narrow “ticket-closing” developer job. You won’t be handed tightly scoped Jira tasks inside a heavily layered team structure. You won’t be maintaining a disposable MVP. And you won’t be managing people. Instead, you’ll be working on the core platform that underpins Outsmart’s crowdsourcing operations – a mature, revenue-generating system that has evolved over years and continues to scale. If you enjoy owning real systems, thinking architecturally, improving legacy code thoughtfully rather than rewriting it, and being trusted to deliver without heavy supervision, this role will feel unusually well-matched.

The role As Senior Fullstack Software Engineer, you will help design, build and maintain the production systems that power Outsmart’s platform. You’ll work closely with our CTO, operating as a high-agency individual contributor with genuine ownership across backend systems, infrastructure and platform evolution. This is a role for someone who wants to:

  • Work on real, live systems with meaningful operational responsibility
  • Make architectural decisions, not just implement them
  • Improve and extend an existing platform with care and judgement
  • Help shape the engineering foundations for the next stage of company growth

You will be trusted to take product and operational requirements and translate them into robust, production-ready solutions.

What you’ll be doing:

  • Designing and maintaining backend services primarily in Python
  • Developing and evolving well-structured RESTful APIs
  • Designing and improving data models across relational (e.g. PostgreSQL) and NoSQL databases
  • Working across the stack where needed, including JavaScript, modern HTML/CSS, and utility frameworks such as Tailwind
  • Contributing to cloud-based infrastructure (e.g. Google Cloud), deployment pipelines and DevOps practices
  • Debugging live production issues with a calm, root-cause mindset
  • Incrementally improving system architecture using sound design principles (including modular design, DDD-style thinking, and pragmatic architectural patterns)
  • Reviewing code, raising standards constructively, and contributing to a disciplined engineering culture
  • Leveraging modern tooling (including AI-assisted development) to improve quality and velocity

This is not greenfield experimentation. It is thoughtful, high-quality engineering on systems that matter.

The environment We are a small, intellectually serious company. That has advantages and responsibilities. You will:

  • Speak directly with senior decision-makers when needed
  • Operate without perfect documentation
  • Balance speed with long-term maintainability

This role suits someone comfortable with autonomy, accountability and cross-functional collaboration.

Who this role is for This role is designed for someone who is:

  • 8–15 years into their engineering career
  • Has worked in a small company (c. 5–30 people) or similarly lean environment without heavy process
  • Experienced in inheriting and improving mature systems
  • Comfortable reading and navigating complex legacy code
  • Strong in systems thinking (trade-offs, scalability, cost implications)
  • Backend-heavy, with strong Python expertise
  • Operationally mature – you’ve supported production systems, not just built features

You are likely:

  • Calm under pressure
  • Direct but not ego-driven
  • Curious and thoughtful rather than dogmatic
  • Comfortable challenging ideas constructively

If you primarily identify as a manager, a greenfield-only builder, or someone who prefers heavy structure and layered sign-off, this role is unlikely to be a good fit.

Practicalities Schedule: Monday to Friday Weekends: No Location: UK-based Working style: Hybrid (remote and London office)

Why Outsmart Insight? Outsmart Insight operates at the intersection of technology, intelligence and large-scale coordination. Our internal platform powers a global network and supports complex, high-trust client engagements. We are deliberately serious about quality, reliability and long-term thinking. As we grow, we are investing in strengthening our engineering foundations – building systems that are robust, scalable and thoughtfully designed. If you want to work somewhere where your engineering judgement genuinely matters, this is that opportunity.

Our values:

  • Smart minds, working together
  • Quality delivered every time
  • Strong client relationships built on trust
  • Hard work, rewarded
  • A happy, healthy team

Apply Send a short cover letter and a two-page CV to careers@outsmartinsight.com, outlining why this role, and this type of engineering work, appeals to you. Please note: only applications sent directly to this email address will be considered.

Senior Fullstack Software Engineer employer: Outsmart Insight

Outsmart Insight is an exceptional employer for Senior Fullstack Software Engineers, offering a unique opportunity to work on meaningful, mature systems that are integral to the company's operations. With a strong emphasis on quality and reliability, employees enjoy a collaborative work culture that values autonomy and accountability, alongside opportunities for professional growth in a hybrid working environment based in the UK. The company fosters a disciplined engineering culture where your contributions directly impact the platform's evolution, making it an ideal place for those seeking to make a real difference in their work.
Outsmart Insight

Contact Detail:

Outsmart Insight Recruiting Team

StudySmarter Expert Advice 🤫

We think this is how you could land Senior Fullstack Software Engineer

✨Tip Number 1

Network like a pro! Reach out to your connections in the industry, attend meetups, and engage in online communities. You never know who might have the inside scoop on job openings or can put in a good word for you.

✨Tip Number 2

Show off your skills! Create a portfolio showcasing your projects, especially those that demonstrate your ability to improve legacy systems and design robust solutions. This will give potential employers a taste of what you can bring to the table.

✨Tip Number 3

Prepare for interviews by brushing up on your technical knowledge and problem-solving skills. Be ready to discuss your experience with backend services, RESTful APIs, and cloud-based infrastructure. We want to see how you think and approach challenges!

✨Tip Number 4

Apply through our website! It’s the best way to ensure your application gets seen. Tailor your cover letter to highlight why you’re a great fit for the role and how your experience aligns with our values at Outsmart Insight.

We think you need these skills to ace Senior Fullstack Software Engineer

Python
RESTful APIs
PostgreSQL
NoSQL databases
JavaScript
HTML/CSS
Tailwind
Google Cloud
DevOps practices
Debugging
System Architecture
Modular Design
Domain-Driven Design (DDD)
Code Review
AI-assisted Development

Some tips for your application 🫡

Craft a Compelling Cover Letter: Your cover letter is your chance to shine! Make sure to express why this role excites you and how your experience aligns with our needs. Be genuine and let your personality come through – we want to see the real you!

Tailor Your CV: Don’t just send a generic CV! Highlight your relevant experience, especially in backend systems and Python. We’re looking for someone who’s comfortable with legacy code and can demonstrate their architectural thinking, so make sure that shines through.

Showcase Your Problem-Solving Skills: In your application, share examples of how you've tackled complex issues in production systems. We love candidates who can think critically and calmly under pressure, so don’t hold back on those stories!

Apply Through Our Website: Remember, we only consider applications sent directly to careers@outsmartinsight.com. So, make sure you follow this step! It shows us you’re detail-oriented and serious about joining our team.

How to prepare for a job interview at Outsmart Insight

✨Know Your Systems

Before the interview, brush up on your understanding of mature systems and legacy code. Be ready to discuss how you've improved existing platforms in the past, as this role is all about thoughtful engineering rather than starting from scratch.

✨Showcase Your Architectural Thinking

Prepare to talk about architectural decisions you've made in previous roles. Think about specific examples where you balanced speed with long-term maintainability, as this will resonate well with the team looking for someone who can think critically about system design.

✨Demonstrate Calm Under Pressure

Since debugging live production issues is part of the job, be ready to share experiences where you handled high-pressure situations. Highlight your calm, root-cause mindset and how it helped you resolve issues effectively.

✨Engage in Constructive Dialogue

This role values direct communication without ego. Prepare to discuss how you've constructively challenged ideas in the past and contributed to a disciplined engineering culture. This will show that you're not just a team player but also someone who can elevate the team's standards.

Senior Fullstack Software Engineer
Outsmart Insight

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