Senior Android Engineer (Mobile Security)

Coltech; Manchester; On-site; GBP 92,000 - 148,000; Part time

Job summary

Coltech in Manchester seeks a Senior Android Engineer (Contract) to join its Mobile Security team, delivering security-focused Android applications at scale.

You will design and build modular, Kotlin/Java apps using modern architecture, collaborating with security and engineering teams, and driving best practices, testing, and CI/CD in a regulated banking environment.

This role offers exposure to security hardening, performance tuning, and scalable delivery within enterprise platforms.

Qualifications

• Strong experience designing and building Android apps with Kotlin/Java.
• Experience with modularised Android codebases and Jetpack components.
• Familiarity with Android security best practices.
• Experience with UI testing and CI/CD pipelines.
• Knowledge of SOLID principles and scalable architectures.

Responsibilities

• Design, develop, and maintain Android apps, libraries, and security components.
• Build scalable, modular mobile solutions using modern Android architecture patterns.
• Collaborate with stakeholders to architect secure mobile solutions.
• Drive best practices in development, testing, and code quality.
• Optimise performance, reliability, and scalability.
• Contribute to design discussions and influence engineering strategy.
• Support automated testing, CI/CD, and deployment initiatives.
• Champion clean code and continuous improvement.
• Work with Kotlin/Java, Git, and security-focused Android development.

Skills

Kotlin

Java

Android SDK

Jetpack Compose

Jetpack Libraries

SOLID Principles

Modularised Android codebase

UI tests

CI/CD

Agile

Android architecture patterns

Performance tuning

Security principles

Tools

Git

Job description

Senior Android Engineer (Mobile Security) - Contract

The Opportunity

We're seeking a Senior Android Engineer to join a leading Mobile Security team within a major banking environment. This team is responsible for delivering security capabilities across the mobile channel, providing a suite of security components and services that help protect Android applications at scale.

You'll be responsible for designing, developing, and maintaining security-focused mobile solutions while collaborating closely with engineering and strategy teams to architect and implement robust, scalable Android applications. This role is ideal for an engineer who enjoys building reusable mobile components, influencing technical direction, and working within a modern engineering culture.

Responsibilities

• Design, develop, and maintain high-quality Android applications, libraries, and security components.
• Build scalable, modular mobile solutions using modern Android architecture patterns.
• Collaborate with stakeholders and engineering teams to architect and deliver secure mobile solutions.
• Drive engineering best practices across development, testing, and code quality.
• Optimise application performance, reliability, and scalability.
• Work within a modularised codebase, promoting code reuse and maintainability.
• Contribute to technical design discussions and influence engineering strategy.
• Support automated testing, continuous integration, and delivery initiatives.
• Champion software craftsmanship, clean code principles, and continuous improvement.
• Strong commercial experience developing Android applications using Kotlin and Java.
• Excellent understanding of the Android SDK and Android development best practices.
• Strong knowledge of Android UI design principles, patterns, and guidelines.
• Experience with:
• Offline storage
• Threading and concurrency
• Performance tuning and optimisation
• Strong understanding of the Android open-source ecosystem and commonly used libraries.
• Experience using source control tools such as Git.
• Solid understanding and practical application of SOLID Principles.
• Experience with:
• Jetpack Libraries
• Strong commercial experience with Jetpack Compose.
• Experience working within a modularised Android codebase.
• Experience writing and maintaining UI tests.
• Ability to contribute across the full software development lifecycle.
• Knowledge of mobile security principles and Android security best practices.
• Exposure to mobile application hardening, obfuscation, or penetration testing practices.
• Experience with CI/CD pipelines and automated deployment processes.
• Familiarity with Agile delivery methodologies.
• Previous experience within Financial Services or other highly regulated environments.

Why Apply?

• Join a team responsible for securing mobile applications used by millions of customers.
• Work on enterprise-scale Android platforms with a strong engineering focus.
• Influence architecture and best practices within a highly collaborative environment.
• Gain exposure to mobile security, application hardening, and secure development practices.
• Competitive day rate and long-term contract potential.