Senior Software Developer

Job Title: Senior Software Developer
Location: London or Cardiff- once a month in the office
Salary/Rate: £500-£600 daily rate
Start Date: 05/05/2026
Job Type: Contracted for 12 months

Company Introduction
We have an exciting opportunity now available with one of our data analytics clients! They are currently looking for a skilled Senior Software Developer to join their team for a twelve-month contract.

Job Responsibilities/Objectives

We are looking for a Senior Software Developer to design, build, and maintain microservices-based applications and data engineering pipelines. This role requires strong hands-on development experience across Java services,backend systems, and data processing platforms, with a focus on building scalable, reliable, and maintainable solutions. The role involves close collaboration with data engineers, QA, product, and platform teams to deliver high-quality services and data products across a complex enterprise environment.

• Strong hands-on experience developing Java-based applications in a microservices architecture.
• Solid experience building and maintaining backend services and APIs.
• Experience contributing to data engineering pipelines, including ETL/ELT workflows, batch processing, and scheduled data builds.
• Strong understanding of data modelling, transformations, and downstream data consumption.
• Experience with performance tuning for backend services or data pipelines.
• Proficient SQL skills for data analysis, validation, and troubleshooting.
• Experience working with data warehouses, data lakes, or big data platforms(e.g., Snowflake, Redshift, BigQuery, Spark).

Required Skills/Experience
The ideal candidate will have the following:

• Experience with CI/CD pipelines and automated build and deployment processes.
• Strong experience with version control systems(Git).
• Experience developing in cloud environments(Azure, AWS, or GCP).
• Understanding of distributed systems, service communication patterns, and fault tolerance.
• Familiarity with containerization and orchestration(e.g., Docker, Kubernetes) is desirable.

Key Responsibilities

• Design, develop, and maintain Java-based microservices and backend systems.
• Contribute to the development and enhancement of data pipelines and data builds, ensuring reliable and efficient data processing.
• Implement scalable and maintainable solutions aligned with architectural standards.
• Collaborate with data engineers to ensure data accuracy, consistency, and performance across pipelines and services.
• Participate in code reviews, design discussions, and architectural decision-making.
• Support CI/CD pipelines, deployments, and production releases.
• Troubleshoot and resolve application and data-related issues across environments.
• Work closely with QA and automation engineers to ensure testability and high-quality releases.
• Actively contribute to Agile ceremonies, including sprint planning, refinement, and retrospectives.
• Mentor junior developers and contribute to improving engineering standards and practices.

Desirable Skills/Experience

• Exposure to data quality, monitoring, or observability tools.
• Experience working in Agile/Scrum delivery environments.

Disclaimer
Notwithstanding any guidelines given to level of experience sought, we will consider candidates from outside this range if they can demonstrate the necessary competencies.
Square One is acting as both an employment agency and an employment business, and is an equal opportunities recruitment business. Square One embraces diversity and will treat everyone equally. Please see our website for our full diversity statement.