Senior Android Engineer

As a Senior Software Engineer for Android at MZLA, you will play a key role in shaping Thunderbird’s mobile platform. With a successful launch of Thunderbird for Android in 2024, we’ve set a baseline for you to expand on.  You will be delivering improvements to hundreds of thousands of email users worldwide, and building exciting features that support productivity. You have the opportunity to evolve the application architecture, create best practices, and implement new Android features as the platform changes.

The ideal candidate is a seasoned engineer who will have deep expertise in mobile application development for Android, with experience using languages and frameworks such as Kotlin and Jetpack Compose. You have a proven ability to work with mature codebases, identifying opportunities to modernize, optimize, and enhance long-term sustainability within open-source environments.

This is a leading role with the opportunity to shape technical direction and ensure exceptional performance. This role focuses on evolving the mobile platform to meet the needs of Thunderbird’s global user base.

We’re committed to creating an amazing experience for our users, and you’ll play a key part in this effort. As part of the MZLA Mobile team you will be working with our existing staff and community members from all over the globe to support the mission and objectives of MZLA Technologies Corp and the Thunderbird Project. Additionally, you’ll have the opportunity to engage with other mobile engineers across the broader Mozilla ecosystem.

The Sr Software Engineer, Android is an individual contributor and will report directly to the Senior Manager, Mobile Engineering.

This is a remote, full time position. We require strong written communication skills to facilitate effective work coordination across various virtual communication platforms such as email and video conferencing.

This role works closely with staff across Europe, US and Canada. Consequently, applicants in the Eastern Standard or Western/Central European Standard time zones are strongly preferred.

What you’ll do: 

• Build and refine Thunderbird’s mobile products and platform architecture, ensuring scalability, performance, reliability, and user-centered design.
• Develop a deep understanding of the codebase and architecture to confidently make changes across the entire stack.
• Develop and maintain strong debugging and testing practices, utilizing unit, integration, and automated testing frameworks to ensure software quality and reliability.
• Conduct thorough code reviews and provide guidance on architectural improvements, test integration and development best practices.
• Independently resolve technical challenges, including performance bottlenecks, security vulnerabilities and cross-platform integration.
• Monitor application vitals and identify potential issues before they escalate.
• Document technical decisions, systems architecture, and team processes to ensure transparency, maintainability, and knowledge transfer.
• Own assigned projects, collaborating cross-functionally to investigate, plan, develop, validate, and deliver within established project timelines.
• Work directly with users and contributors to gather information to reliably reproduce bugs and then fix them.
• Ensure compliance with accessibility, security, and privacy standards in mobile development.
• Leverage analytics and user feedback to inform and improve mobile user experiences.
• Mentor and guide community contributors, enabling their active participation and long-term involvement in our efforts.

What you’ll bring: 

• 7+ years of professional development experience with at least 2+ years in a Senior Software Engineer role.
• 3+ years of mobile development experience with native languages such as Kotlin and frameworks such as Jetpack Compose, and a deep understanding of mobile app architectures and patterns.
• Proven ability to deliver and maintain complex software projects, ensuring quality, scalability, and reliability throughout the software development lifecycle.
• Demonstrated interest in building software that runs on multiple platforms, with an understanding of the associated challenges and trade-offs.
• Strong understanding of security practices, including data encryption, secure storage, app signing, and addressing vulnerabilities in mobile platforms.
• Advanced proficiency with version control systems (e.g., Git) and experience working in a collaborative environment.
• Strong attention to detail, with excellent learning and exploration skills and a product-focused mindset that looks beyond the code to consider user needs and business goals.
• Deep respect for diverse skills and perspectives, with an ability to collaborate effectively across technical and non-technical teams.
• Excellent English written and verbal communication skills, with the ability to clearly and concisely engage with an international, geographically distributed team.

Bonus points for:

• Familiarity with app store guidelines (Google Play Store, Apple App Store) for ensuring compliance when preparing apps for release.
• Hands-on experience developing cross-platform applications using Kotlin Multiplatform, Rust, or similar frameworks.
• Proficiency in iOS application architecture and differences between iOS and Android development.
• Experience contributing to open-source projects or engaging with open-source communities.
• Proficiency in one of the top languages Thunderbird is translated to, such as French, German, or Japanese.

What you’ll get:

We benchmark our base salaries to local markets and target the 60th percentile of the peer market. The salary ranges for this role are:

• UK: 60,000-73,000 GBP

In addition to competitive salaries, we offer a comprehensive benefits package designed to support your whole self.

Work & Career

• Fully remote work & schedule flexibility
• Latest Laptop and accessories
• Annual Remote Work Stipend
• Monthly Internet Stipend
• Professional Development Stipend
• Industry Conferences

Rest & Play

• 24 days PTO per year (prorated)
• Your Birthday
• Year-end Company Shutdown
• Wellbeing Days
• Public Holidays
• Other Paid Leave
• Wellbeing Allowance for Personal / Family Activities

Health & Family

• Pension Contributions
• Health, Dental, & Vision Insurance
• Disability/Income Protection Insurance
• Life Insurance
• Employee Assistance Program
• Paid Parental Leave
• Paid Sick Days

*Applicants must reside in and have work authorization for one of the country locations specified above. We are unable to consider applicants outside of these markets at this time. And we are unable to provide visa sponsorship

MZLA Technologies Corporation (MZLA) Commitment to diversity, equity and inclusion

MZLA believes in the value of diverse creative practices and forms of knowledge, and knows diversity, equity and inclusion are crucial to and enrich the company’s core mission. We encourage applications from everyone, including members of all equity-seeking communities, such as (but not limited to) women, racialized and Indigenous persons, persons with disabilities, persons of all sexual orientations, gender identities and expressions.

We are an equal opportunity employer. We do not discriminate on the basis of race (including hairstyle and texture), religion (including religious grooming and dress practices), gender, gender identity, gender expression, color, national origin, pregnancy, ancestry, domestic partner status, disability, sexual orientation, age, genetic predisposition, medical condition, marital status, citizenship status, military or veteran status, or any other basis covered by applicable laws. Mozilla will not tolerate discrimination or harassment based on any of these characteristics or any other unlawful behavior, conduct, or purpose.

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