Back end developer job description.

What does a back end developer do?

 

A back end developer builds the server-side logic that powers websites and apps. They focus on databases, APIs, authentication, and system architecture to ensure everything runs securely and efficiently behind the scenes.

 

Core responsibilities include writing scalable code in languages like Python, Java, or Node.js, optimising server performance, integrating external services, and collaborating with front end developers.

 

In smaller teams, they may manage infrastructure too. In larger organisations, they specialise in backend systems and often work alongside DevOps, QA, and security teams to ensure application stability and scalability.

 

Key responsibilities of a back end developer.

 

Back end developers are responsible for building and maintaining server-side systems. Their core duties usually include:

• Writing code for server-side applications using Node.js, Python, PHP, or similar

• Designing and managing databases, queries, and schema optimisation

• Developing RESTful APIs to support front-end functionality

• Ensuring data security, authentication, and authorisation protocols

• Optimising performance for scalability and reliability

• Collaborating with front-end developers and DevOps teams

• Managing deployments, environment configurations, and CI/CD pipelines

• Debugging issues and resolving bugs in live environments

• Maintaining server logs, documentation, and monitoring tools

• Supporting migrations, system upgrades, or refactoring initiatives

The role focuses on functionality, data, and stability behind the scenes of digital products.

 

Skills and requirements for a back end developer.

 

Back end developers build logic, databases, and systems powering web applications. Employers typically look for:

• 2–5 years of experience in server-side development

• Strong programming skills in Node.js, Python, Java, or PHP

• Experience working with relational and NoSQL databases

• Understanding of REST APIs, authentication, and integration workflows

• Familiarity with CI/CD pipelines and version control tools

• Knowledge of server architecture, cloud hosting, and scaling

• Ability to troubleshoot, debug, and optimise backend logic

• Confidence working with front-end teams to align architecture

• Understanding of data structures, caching, and performance

Most back end developers work across web platforms, SaaS products, or enterprise tools.

 

Average salary for a back end developer.

 

In the UK, the average salary for a back end developer typically ranges from £45,000 to £65,000, based on architecture design, API development, and security knowledge.

• Mid-level back end developers tend to earn between £45,000 and £55,000

• Senior back end specialists with cloud integration or microservices experience may earn between £56,000 and £65,000

• High-load systems and fintech environments tend to offer the most competitive pay packages

London and high-tech regions are hotspots for Python, Node.js, and .NET-focused roles.

 

Career progression for a back end developer.

 

A back end developer is responsible for server-side logic, APIs, and data integration. This technical role can evolve into architecture, DevOps, or engineering leadership. A typical path includes:

 

Junior back end developer

 

Supports database management, simple API creation, and infrastructure maintenance.

 

Back end developer

 

Builds scalable services and integrations. Works with tools like Node.js, Python, PHP, or Java.

 

Senior back end developer

 

Designs database schemas, manages API security, and handles infrastructure scaling.

 

Technical architect / DevOps lead

 

Shapes system infrastructure and cloud deployment strategies.

 

Head of engineering / CTO

 

Leads platform design, technical vision, and product development across teams.