Full-Stack Staff Product Engineer

MZLA Technologies Corporation (MZLA) is a wholly owned, for-profit subsidiary of the Mozilla Foundation and home to Thunderbird, our flagship open-source email and productivity platform empowering more than 20 million people around the world. While part of the Mozilla portfolio of companies, MZLA operates independently in both identity and organizational structure from the Mozilla Foundation and Mozilla Corporation.

Everything we build at MZLA is open source, developed transparently and in collaboration with a global community of contributors. This open approach shapes not only our products but also how we work: collaboratively, inclusively, and with a shared commitment to building technology that puts users first. We believe privacy and productivity should coexist, and that people deserve powerful digital tools without surrendering control of their data.

MZLA is a small but growing team of 50+ people distributed across seven countries. As we evolve Thunderbird from a single application into a suite of privacy-respecting productivity tools, we?re introducing new products and services that remain independent of big tech ecosystems. Our unique revenue model combines community donations that keep Thunderbird freely available with subscriptions for new cloud-based services, allowing us to grow and innovate while remaining independent and true to our values.

To learn more, visit www.thunderbird.net

The Opportunity:

MZLA is developing a new privacy-centric AI assistant that empowers users to build their own experience through an extension marketplace. The product is cross-platform (web, mobile, desktop) and built on a modern stack : TypeScript, React, Tauri, Rust, and the Vercel AI SDK. Our local-first architecture ensures that all data stays on-device, encrypted at rest, with optional sync. We?re tackling complex problems at the intersection of AI, context engineering, and desktop app development.

We?re looking for a generalist Full-Stack Staff Product Engineer who thrives on ownership and versatility. This is not a ?stay in your lane? role ? you?ll work across the entire stack, from frontend and backend to desktop shell and AI integrations, helping shape the foundation of a new product.

What You?ll Do:

• Design and implement end-to-end features across the stack.

• Make architectural decisions that influence the entire product.

• Build responsive UIs in React using modern patterns (hooks, server components, streaming).

• Develop local-first data sync and storage strategies.

• Integrate AI/LLM capabilities (streaming, embeddings, agentic workflows).

• Create cross-platform desktop experiences with Tauri.

• Implement email parsing, IMAP sync, and message intelligence.

• Build real-time features using WebSockets and server-sent events.

• Optimize performance for on-device ML inference.

• Own the full product development cycle ? from concept to release.

What You?ll Bring:

• 10+ years of professional software development experience

• 5+ years focused on frontend development

• 3+ years of experience with React

• 3+ years of experience with TypeScript

• Experience delivering vertically integrated features across the stack (monorepo environments a plus)

• Strong system design skills ? data flow, state management, caching, and API design

• Strong product sense ? attention to UX, reducing friction, and thinking beyond specs

• Experience with AI product development (at least 1 year preferred)

• Fast learner with a growth mindset ? comfortable working with emerging tools and technologies

• Excellent written and verbal communication skills

• Proven ability to collaborate with developers, designers, and product managers

• Commitment to open-source development and open standards

Bonus Points For:

• Experience with local-first architectures (CRDTs, SQLite, IndexedDB)

• Building cross-platform apps (Electron, Tauri, React Native, etc.)

• Working with AI/LLM APIs (OpenAI, Anthropic, local models)

• Previous contributions to open-source projects or communities

• Experience leading open-source project initiatives

Work Environment:

You?ll join a small, ambitious team shaping the future of privacy-first AI experiences, collaborating with staff and community members worldwide to create exceptional user experiences and advance MZLA?s mission.

This is a remote full-time position, open to candidates in Canada and the US. Strong communication and documentation skills are essential for effective collaboration across time zones and disciplines.

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: 

• US: $150,000 - $175,000 USD 

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

• Latest Laptop 

• Remote Work Stipend

• Professional Development Stipend

• Access to Udemy Learning Platform

• Industry Conferences

• Company All Hands

Rest & Play

• 24 days PTO per year (prorated) 

• Your Birthday

• Year-end Company Shutdown

• Wellbeing Days

• Public Holidays

• Other Paid Leave

• Wellbeing Stipend for Personal / Family Activities

Health & Family

• 401(k) 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. We carefully review every cover letter and screening question, so take the time to answer each fully. We also value authenticity. We want to hear your perspective, not a bot?s. It's fine to use AI to polish your writing, but not to write your answers. Candidates who submit unoriginal AI generated answers will be disqualified from further screening. 

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. 

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 [email protected] to request accommodation.