What does a software engineer do?
A software engineer designs, develops, and maintains software applications used by businesses or consumers. They write code, test systems, and solve technical challenges across a product’s lifecycle.
Their role involves working with cross-functional teams to define requirements, write scalable code, implement testing strategies, and deploy features into production. Languages and frameworks vary by company, but often include Java, C#, Python, or JavaScript.
In product-led companies, Software engineers work closely with product managers and designers. In service-based or enterprise organisations, they may specialise in modules, integrations, or legacy systems.
Key responsibilities of a software engineer.
Software engineers are typically involved in building scalable, high-quality software solutions. Responsibilities often include:
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Designing and developing applications based on user or business requirements
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Writing clean, maintainable code in languages such as Python, Java, or C#
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Collaborating with product managers and designers to define features
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Testing and debugging code across environments
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Participating in code reviews and sprint planning sessions
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Creating system documentation and technical specs
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Integrating APIs and third-party services
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Following development best practices, including version control and CI/CD
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Supporting system upgrades and refactoring initiatives
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Contributing to technical decision-making and architecture discussions
The role combines engineering precision with collaboration and continuous delivery.
Skills and requirements for a software engineer.
Software engineers design and build scalable applications, tools, and platforms. Employers typically look for:
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2–6 years of experience in software engineering or application development
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Strong programming skills in Python, Java, JavaScript, or C#
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Experience with system architecture, APIs, and integration workflows
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Understanding of Agile methodologies and version control tools
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Experience writing clean, testable, and maintainable code
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Familiarity with CI/CD pipelines and unit testing
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Ability to solve complex technical challenges
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Knowledge of database structures and data modelling
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Confidence in debugging, performance tuning, and code reviews
Most software engineers have a degree in computer science or relevant training, focusing on systems thinking and reliability.
Average salary for a software engineer.
In the UK, the average salary for a software engineer typically ranges from £40,000 to £60,000, depending on coding language, system design experience, and industry.
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Mid-level software engineers tend to earn between £40,000 and £50,000
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Senior engineers working with complex architectures or DevOps processes often earn between £51,000 and £60,000
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Financial services, AI, and cloud-native environments usually offer above-average packages
Pay tends to be higher in London, and remote-first tech product companies.
Career progression for a software engineer.
A software engineer designs and develops scalable systems, apps, or platforms. It’s a versatile technical role with potential to progress into architecture, leadership, or specialist domains. Common progression includes:
Junior software engineer
Supports bug fixes, builds new features, and learns the system architecture.
Software engineer
Owns modules, contributes to architecture, and participates in code reviews and Agile workflows.
Senior software engineer
Leads projects, mentors others, and makes key architectural decisions.
Engineering manager / principal engineer
Manages team performance or owns high-level technical direction.
Head of software / CTO
Takes full responsibility for development strategy, systems performance, and team leadership.
System Developer
Electrician
Data Cabling
Electrical Improver
salary guide
Our UK tech salary guide.
Software engineers develop scalable systems and solve complex technical problems. Whether you're hiring or progressing your career, compensation should match impact and expertise.
Use our 2025 UK tech salary guide to explore salary benchmarks, changes from 2024, hiring insights, and 2026 salary projections.
FAQS
Software engineer FAQs.
Software engineers are essential across sectors including SaaS, fintech, healthtech, logistics, gaming, and e-commerce. Roles also exist in media, energy, and government, especially where software powers operations, customer platforms, or automation.
“Developer” is often used for those focused on implementation, while “software engineer” usually suggests deeper involvement in architecture, system design, and scalability. Engineers often think beyond code — focusing on design patterns, infrastructure, and long-term maintainability.
Strong candidates bring both clean code and architectural thinking. Look for experience with version control, code review processes, and problem-solving within cross-functional teams. Curiosity, communication, and testing knowledge are also key differentiators.
Sometimes. Many engineers specialise in back end or infrastructure, while others work full stack. The core requirement is the ability to build stable, scalable systems and collaborate effectively with frontend, QA, and DevOps teams.
Engineers often move into senior software engineering, then into either technical lead or principal engineer roles. Some shift into engineering management or transition toward architecture, DevOps, or product-adjacent roles depending on strengths and interests.
