Software Engineer

Addition; Warmley; Hybrid; GBP 65,000 - 90,000; Full time

Job summary

Addition is seeking a Software Engineer to design, develop and deliver secure digital solutions for Defence and National Security contexts. You will work with Kotlin/Jetpack Compose on Android and with Rust/Python/Go on backend APIs, in a hybrid Cheltenham setting with 3 days in the office weekly.

The role emphasizes PoC development, secured environments, CI/CD pipelines and collaboration within cross-functional teams to deliver high-assurance software.

Qualifications

• Bachelor’s degree in Computer Science, Engineering or related field.
• Strong proficiency with Git.
• Strong experience in Android/Kotlin development, including Jetpack Compose.
• Experience developing PoC applications in environments where requirements can change quickly.
• Familiarity with backend development using Rust, Python or Go.
• Understanding of software development principles including MVVM and UDF.
• Understanding of Web APIs, OpenAPI standards and data structures.
• Experience with Docker and containerised deployments.
• Knowledge of DevOps processes, including CI/CD pipelines and automated testing.
• Strong communication and collaboration skills.
• Ability to work in a fast-paced and evolving technical environment.

Responsibilities

• Collaborate with the development team to design, develop and maintain software solutions.
• Develop reliable applications using Kotlin and Jetpack Compose for Android.
• Use Git for version control and collaborative development.
• Design and implement backend solutions using Rust, Python or Go, including web APIs.
• Use Docker for containerisation and deployment.
• Implement and maintain CI/CD pipelines to automate software delivery and deployment.
• Write clean, efficient and well-documented code following industry best practices.
• Participate in code reviews and provide constructive feedback to team members.
• Develop PoC applications where requirements may change rapidly and rework is expected.
• Stay up to date with emerging technologies, development practices and industry trends.
• Work effectively within secure development environments, including remote developer environments and virtual machines.

Skills

Android/Kotlin

Jetpack Compose

Git

PoC development

Secure environments

Education

Bachelor’s degree in Computer Science or related field

Tools

Kotlin

Jetpack Compose

Git

Rust

Python

Go

Docker

OpenAPI

CI/CD

Job description

Software Engineer

• Location: Cheltenham
• Salary: DOE
• Working Pattern: Monday–Friday, hybrid
• Office Requirement: 3 days per week in the Cheltenham office
• Additional Travel: Occasional visits to Herefordshire
• Security Requirement: Must be eligible for UK SC Clearance

We are working with a specialist technology organisation delivering secure, mission-critical digital solutions to Defence and National Security organisations.

They are looking for a Software Engineer who enjoys solving complex technical challenges and wants to work on technology with genuine operational impact.

Due to the nature of the work, you must be eligible to obtain UK Security Clearance (SC).

The role is based in Cheltenham, with a hybrid working pattern of 3 days per week in the office, Monday to Friday. There may also be occasional travel to Herefordshire.

The Role

As a Software Engineer, you will help design, develop and deliver secure digital solutions within highly secure environments. You will work alongside engineers, architects and delivery specialists to develop technology that enables faster and safer decision-making for critical operations.

Key Responsibilities

• Collaborate with the development team to design, develop and maintain software solutions.
• Develop reliable applications using Kotlin and Jetpack Compose for Android.
• Use Git for version control and collaborative development.
• Design and implement backend solutions using Rust, Python or Go, including web APIs.
• Use Docker for containerisation and deployment.
• Implement and maintain CI/CD pipelines to automate software delivery and deployment.
• Write clean, efficient and well-documented code following industry best practices.
• Participate in code reviews and provide constructive feedback to team members.
• Develop Proof of Concept (PoC) applications where requirements may change rapidly and rework is expected.
• Stay up to date with emerging technologies, development practices and industry trends.
• Work effectively within secure development environments, including remote developer environments and virtual machines.

What We’re Looking For

We are looking for someone who takes ownership, thinks critically and enjoys working collaboratively on challenging technical problems.

You don’t need to meet every requirement, but experience with the following would be highly beneficial:

• Bachelor’s degree in Computer Science, Engineering or a related field.
• Strong proficiency with Git.
• Strong experience in Android/Kotlin development, including Jetpack Compose.
• Experience developing PoC applications in environments where requirements can change quickly.
• Familiarity with backend development using Rust, Python or Go.
• Understanding of software development principles including MVVM and UDF.
• Understanding of Web APIs, OpenAPI standards and data structures.
• Experience with Docker and containerised deployments.
• Knowledge of DevOps processes, including CI/CD pipelines and automated testing.
• Strong communication and collaboration skills.
• Ability to work in a fast-paced and constantly evolving technical environment.
• Comfortable developing within secure environments, including remote development environments and VMs.
• Strong problem-solving skills, curiosity and a willingness to learn new technologies.

Security Clearance

Due to the secure nature of the role and working environment, candidates must be eligible to obtain UK Security Clearance (SC).

Why Join?

You will join an organisation working on complex, technically challenging projects across Defence and National Security, with the opportunity to make a genuine impact through secure and innovative technology.

You will be part of a collaborative and inclusive environment focused on agility, security, innovation, quality, collaboration and inclusivity.