---
title: 'Senior Mobile Engineer, iOS at Mozilla'
canonical: 'https://feeny.ai/job/senior-mobile-engineer-ios-mozilla-canada-r2792m6t40p0'
type: 'job'
last_seen: '2026-09-10'
---

# Senior Mobile Engineer, iOS at Mozilla

- **Company:** Mozilla
- **Location:** Canada
- **Work type:** remote
- **Posted:** 2026-08-06
- **Last confirmed live:** 2026-09-10
- **Apply:** https://job-boards.greenhouse.io/mozilla/jobs/8112219

## Job description

Why Thunderbird?

Thunderbird is one of the world’s most trusted open-source email applications, empowering more than 20 million people globally. At MZLA, the team behind Thunderbird, we build privacy-respecting communication and productivity tools that help people manage their digital lives while staying in control of their data.

We are open source by design. Our products are developed transparently and in collaboration with a global community of contributors, and that same spirit shapes how we work: collaboratively, inclusively, and with a shared commitment to putting users first.

We are a small but growing company of 60+ people distributed across seven countries. As Thunderbird evolves beyond a single desktop application, we are expanding across desktop, mobile, paid services, and new product experiences that help people and organizations work more effectively without giving up control to big tech ecosystems.

Our revenue model combines user donations, which help keep Thunderbird’s apps freely available, with paid services that cover the costs of hosted offerings while supporting long-term sustainability and continued innovation.

A note about MZLA and Mozilla: MZLA Technologies Corporation is the nonprofit-owned company behind Thunderbird and part of the Mozilla family. MZLA is separate from Mozilla Corporation and has its own compensation programs, benefits, and employment policies.

To learn more, visit [www.thunderbird.net](http://www.thunderbird.net)

The opportunity

The Senior Software Engineer, iOS is an experienced individual contributor who brings deep iOS expertise to the design, development, and evolution of Thunderbird’s iOS application. This role will continue to contribute to Thunderbirds effort to develop the iOS app and establish a strong technical foundation for the product.

You’ll work closely with mobile engineers, product management, UX, and other partners to deliver a high-quality iOS experience that meets high standards for performance, reliability, accessibility, security, and maintainability.

You’ll play an important role in delivering exceptional user experiences for Thunderbird’s global user base by translating product needs into thoughtful technical solutions and ensuring your work aligns with MZLA’s mission and the objectives of the Thunderbird Project. You’ll also collaborate with open-source contributors and mobile engineers across the broader Mozilla ecosystem.

## What you’ll do

- Build and refine Thunderbird’s mobile products and platform architecture.
- Improve scalability, performance, reliability, and user experience.
- Develop a deep understanding of the codebase and architecture to confidently make changes across the entire stack.
- Maintain strong debugging and testing practices across unit, integration, and automated testing.
- Review code and guide improvements to architecture, testing, and development best practices.
- Independently resolve complex issues involving performance, security, and cross-platform integration.
- Monitor application health and address issues before they escalate.
- Document technical decisions, system architecture, and team processes.
- Own assigned projects, collaborating cross-functionally, from investigation and planning through development, validation, and delivery.
- Ensure mobile development meets accessibility, security, and privacy standards.

## What you bring

- 7+ years of professional software development experience, including 2+ years in a Senior Software Engineer role.
- 3+ years of professional mobile application development experience.
- Strong experience with Swift, SwiftUI, and iOS frameworks.
- Deep knowledge of iOS architecture, design patterns, and performance optimization.
- Experience delivering and maintaining complex, scalable, and reliable software.
- Experience addressing technical debt and refactoring large or complex codebases.
- Strong knowledge of mobile security, including encryption, secure storage, app signing, and vulnerability remediation.
- Experience with communication and email protocols such as RSS, IMAP, POP, or Matrix, and familiarity with the IETF standards for CalDav or CardDav.
- Advanced proficiency with Git and collaborative development workflows.
- Strong debugging, testing, and problem-solving skills.
- Strong attention to detail, curiosity, and a product-focused mindset.
- The ability to work independently, take ownership, and collaborate across teams.
- Respect for diverse skills, experiences, and perspectives.
- Excellent async written communication skills; comfortable working with a geographically distributed team.
- Ability to learn, evaluate, and responsibly use emerging technologies, including AI-enabled tools, to improve work processes.

Bonus points for

- Familiarity with Apple App Store and Google Play Store compliance guidelines.
- Experience contributing to open-source projects or communities.
- Proficiency in French, German, Japanese, or another widely supported Thunderbird language.

What success looks like

You’ll be successful in this role if you look beyond shipping features and improve the architecture, reliability, security, and long-term health of the product. You’re comfortable solving ambiguous problems, flagging risks early, documenting decisions, and collaborating across engineering, product, UX, users, and the open-source community.

Over time, your work will help Thunderbird’s iOS experience become more resilient, scalable, and easier for both staff and community contributors to build on.

Work environment

This is a full-time, fully remote position. You’ll join a distributed team of Thunderbird staff, open-source community members, and contributors from around the world.

We rely on clear communication, thoughtful documentation, and collaborative decision-making to work effectively across time zones and disciplines.

## Compensation & benefits

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

- Canada: $108,000 - $125,000 CAD

We may consider candidates with strong skills but less than the required experience. Title, level and compensation will be determined based on qualifications and experience.

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

Work & career

- Fully remote work & schedule flexibility
- Company-provided laptop
- Annual bonus program
- Monthly remote work stipend
- Annual professional development stipend
- Access to Coursera learning platform
- Industry conferences
- Company all-hands and team gatherings

Rest & play

- 24 days PTO per year (prorated)
- Your birthday
- Year-end company shutdown
- 9 wellbeing days
- Public holidays
- Other paid leave
- Quarterly wellbeing stipend for personal / family activities

Health & family

- RRSP contributions
- Health, dental, & vision insurance
- Disability insurance
- Life insurance
- Employee assistance program
- Paid parental leave
- Paid sick days

Work eligibility

Applicants must reside in and have permanent work authorization for the country location(s) specified in the posting. We are unable to consider applicants outside of these markets at this time. And, we do not provide visa sponsorship.

How to apply

Please apply directly through our [career page](https://www.mozilla.org/en-US/careers/listings/?team=MZLA/Thunderbird). We carefully review every cover letter and screening question, so take the time to answer each fully. We value authentic, thoughtful responses that reflect your own experience and perspective. It is fine to use AI tools to polish your writing, but your answers should be your own. Candidates who submit generic or unoriginal AI-generated responses may be disqualified from further consideration.

Our 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. MZLA will not tolerate discrimination or harassment based on any of these characteristics or any other unlawful behavior, conduct, or purpose.

We will ensure that qualified individuals with disabilities are provided reasonable accommodations to participate in the job application or interview process, to perform essential job functions, and to receive other benefits and privileges of employment, as appropriate. Please contact us at hiringaccommodations@thunderbird.net to request accommodation.

## About Mozilla

## Company Overview
- **One-liner**: Mozilla is a global nonprofit-backed technology organization that builds privacy-first browsers, AI tools, and internet health initiatives to keep the internet open and accessible to all.
- **Entity Type**: Private (nonprofit foundation with a for-profit subsidiary — Mozilla Corporation)
- **Headquarters**: San Francisco, California, USA (remote-first globally)
- **Founded**: 1998 (Mozilla Project); 2005 (Mozilla Corporation)
- **Founders**: Originally founded by Netscape staff and the open-source community; key early leaders include Mitchell Baker (current CEO of Mozilla Corporation) and Brendan Eich (creator of JavaScript)

## Core Business
- **Primary industries**: Internet software & services, browser technology, digital privacy, artificial intelligence, online advertising technology
- **Target customers**: B2C (individual users — Firefox browser, Pocket, VPN, Relay); B2B (advertisers and publishers via Anonym); developers (open-source tools, MDN Web Docs, AI developer tools)
- **Mission statement**: "To ensure the internet is a global public resource, open and accessible to all." — Mozilla Manifesto

## Products & Services
- **[Firefox Browser](https://www.mozilla.org/en-US/firefox/)**: Privacy-focused web browser with tracking protection, available on desktop and mobile. Core product.
- **[Mozilla VPN](https://www.mozilla.org/en-US/products/vpn/)**: Virtual private network service for online privacy.
- **[Firefox Relay](https://relay.firefox.com/)**: Email masking service to protect user identities.
- **[Mozilla Pocket](https://getpocket.com/)**: Content discovery and read-later service.
- **[Mozilla Monitor](https://monitor.mozilla.org/)**: Data breach alert and personal data removal service.
- **[Mozilla.ai](https://mozilla.ai/)**: Open-source AI developer tools and trustworthy AI initiatives.
- **[Anonym](https://anonym.co/)**: Privacy-preserving digital advertising measurement platform (acquired by Mozilla in 2022).
- **[Fakespot](https://www.fakespot.com/)**: AI-powered tool to detect fake reviews and counterfeit products (acquired by Mozilla).
- **[MDN Web Docs](https://developer.mozilla.org/)**: Industry-standard web development documentation and learning platform.
- **[Mozilla Ventures](https://mozilla.vc/)**: Venture capital arm investing in responsible tech startups.

## Market Standing
- **Valuation/Market Cap**: Not publicly disclosed (private, nonprofit-backed organization)
- **Key Revenue**: Approximately $593 million in total revenue (2022, latest publicly available — Mozilla Foundation annual report). The majority comes from search partnerships (primarily Google).
- **Notable Partners**: Google (search partnership, revenue driver), Meta (via Anonym), Amazon, eBay, and major ad-tech platforms.
- **Growth Signals**: Mozilla has aggressively expanded through acquisitions (Anonym, Fakespot, Pulse, Active Replica); launched Mozilla.ai to bet on open-source AI; growing headcount across engineering, AI, and privacy product teams. As of 2024, the organization employs roughly 800–900+ people globally.

## Competitive Advantages
- **Brand trust and mission**: Uniquely positioned as a "not-for-profit" tech company — no shareholder pressure to maximize profit at user expense. Consistently ranked among most trusted tech brands.
- **Privacy-first product DNA**: All products are built with privacy and security as core features, not afterthoughts — a strong differentiator vs. Big Tech competitors.
- **Open-source foundation**: Transparent codebase, community-driven development, and strong developer credibility (MDN Web Docs is the gold standard for web dev learning).
- **Diverse revenue streams**: Beyond browser search deals, Mozilla is building a portfolio of subscription products (VPN, Relay, Monitor Plus) and ad-tech (Anonym) to reduce single-partner dependency.
- **Talent and culture**: Decades of experience in remote-first, asynchronous, globally distributed work. Strong engineering culture with deep expertise in privacy, security, and web standards.

## Strategic Focus
- **AI with trust**: Building open-source AI tools and models through Mozilla.ai, emphasizing transparency, privacy, and user agency — contrasting with closed, extractive AI from Big Tech.
- **Product diversification**: Reducing reliance on search revenue by scaling subscription products (VPN, Monitor, Relay) and ad-tech platform (Anonym).
- **Internet health advocacy**: Continuing policy work on data privacy, antitrust, and digital rights through the Mozilla Foundation.
- **Firefox revitalization**: Modernizing the browser with new features (vertical tabs, AI-powered tools, improved performance) to regain market share.
- **Acquisition integration**: Absorbing and scaling recent acquisitions (Fakespot for e-commerce trust, Anonym for privacy-first advertising).

## Why Work Here
- **Culture**: "Remote-first" company with a strong emphasis on asynchronous work, work-life balance, and global collaboration. The culture is mission-driven, collaborative, and values "responsible participation" — generosity and kindness in communication. [mozilla.org](https://www.mozilla.org/en-US/careers/)
- **Benefits (US employees)**:
    - **Health**: 100% premium coverage for medical, dental, and vision for employees and dependents.
    - **Mental health**: Free therapy and coaching sessions.
    - **Time off**: 12+ paid holidays, generous vacation and sick leave (accrued from day one), quarterly company-wide wellness days, and your birthday off.
    - **Parental leave**: 26 weeks paid for childbearing parents, 12 weeks paid for non-childbearing parents.
    - **Remote-first**: Work from anywhere with a strong stipend for home office setup. [mozilla.org](https://www.mozilla.org/en-US/careers/)
- **Engineering culture**: Engineers work on "some of the most interesting challenges facing the internet today — privacy, security, decentralization, access, convenience, compatibility." The Data Organization is at the forefront of using data to guide product decisions while respecting user privacy. [mozilla.org](https://www.mozilla.org/en-US/careers/)
- **Diversity & Inclusion**: Mozilla explicitly states it wants to be "a place where everyone can do their best work" and that "diverse perspectives and experiences result in better solutions." They publish transparency data on their progress.
- **Open roles**: As of mid-2025, Mozilla has ~90 open positions across engineering (Front-End, Machine Learning, Fullstack), product management, data analytics, marketing, and infrastructure. Key teams hiring include Firefox, Anonym, Fakespot, and Mozilla.ai. [greenhouse.io](https://job-boards.greenhouse.io/mozilla?gh_src=e5ad1d6b1us)

## Sources
1. [Mozilla Careers Page](https://www.mozilla.org/en-US/careers/)
2. [Mozilla About Page](https://www.mozilla.org/en-US/about/)
3. [Mozilla Job Board (Greenhouse)](https://job-boards.greenhouse.io/mozilla?gh_src=e5ad1d6b1us)
4. [Mozilla.org Homepage](https://www.mozilla.org/en-US/)
5. [Mozilla Open Positions List](https://www.mozilla.org/en-US/careers/listings/)

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