Senior UX Design Specialist

Why Thunderbird?
MZLA Technologies Corporation (MZLA) is a wholly-owned, for-profit subsidiary of the Mozilla Foundation and the home of Thunderbird. Thunderbird is a global, free, and open-source email and productivity app, which has experienced significant growth in revenue, staff, and aspirations since its launch 20 years ago. Our revenue comes from our dedicated users around the world who generously fund our work. As we continue to expand our team and enhance our products and services, we remain dedicated to providing best-in-class productivity solutions independent of big tech. Operating as a small but dynamic team of 40 + staff across seven countries and time zones, we are part of the larger Mozilla family but maintain our distinct and independent identity from both the Mozilla Foundation and Mozilla Corporation.

Our organizational culture is driven by our mission. We are committed to fostering openness and transparency as a member of the open-source community. We lean into collaboration, creativity, and diversity. We bring a hearty dose of scrappy grit and resilience to our lively and spirited team. Our operating principles leverage data informed decisions, ownership, speed and efficiencies to elevate our work and deliver innovative and impactful solutions to our users.
The Opportunity:
As a Senior UX Design Specialist on the Design Team, you’ll collaborate across desktop, iOS, Android, and web platforms to craft user experiences that embody Thunderbird’s values of openness, accessibility, and user empowerment, driving growth and meaningful engagement. The Design Team is essential to creating a strong visual identity that reinforces MZLA’s brand and presence across all platforms and products.

Working in a small and collaborative team, the Senior UX Design Specialist will mentor growing designers, partner with engineers to optimize development, and elevate products with research-driven UX strategies. They will ensure accessibility and user-centered design across all touch points while delivering impactful solutions. We are looking for an experienced designer with a strong focus on interactive design and UX research, specializing in crafting user-centric experiences that meet high design standards and align design decisions with business goals, accessibility standards and long-term strategies.

The Senior UX Design Specialist is an individual contributor and will report directly to the Manager, Design Studio.

We’re committed to creating an amazing experience for our users, and you’ll play a key part in this effort. 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.

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.
What you’ll do:

• Emphasize user experience, interaction design, and UX research to create exceptional outputs that meet high design standards.
• Lead planning sessions, design jams, design reviews, and production of UX artefacts (diagrams, wireframes, prototypes, and documentation).
• Conduct and lead usability research, apply analytics insights, and refine designs through exceptional research and testing skills.
• Drive projects independently, contribute to design standards, and maintain a high level of initiative and accountability.
• Align design decisions with business goals, user needs, and long-term product strategy.
• Support and mentor team members, fostering skill development and encouraging professional growth.
• Champion user-centric design practices, promoting the value of design across the organization.
• Apply advanced accessibility standards (e.g., WCAG) to create inclusive, user-friendly experiences.

What you’ll bring:

• Bachelor’s degree or equivalent experience in design, human-computer interaction, or a related field. A master’s degree is a plus.
• Advanced certifications or professional training in UX design, interaction design, or usability testing.
• 7+ years of professional experience in UX/UI design, demonstrating expertise and leadership in complex projects.
• Proven ability to design and execute user research, usability testing, and analytics-driven improvements.
• Experience leading the development and maintenance of scalable design systems for multi-platform products.
• A strong portfolio showcasing successful projects, problem-solving skills, and measurable impact on user experience.
• Strong communication skills in technical writing for thorough documentation and guidelines.
• Demonstrated experience mentoring junior and intermediate designers, and leading design initiatives within cross-functional teams.
• Excellent communication skills (both written and verbal), documentation skills, and the ability to work with a multi-disciplinary, geographically distributed team.
• Deep respect for the different skills and perspectives that people of varied technical and non-technical backgrounds bring to a team.
• Proven track record of scoping and finishing projects.

Bonus points for:

• Enthusiasm for user research to guide and support design choices.
• Familiarity with CSS coding for smooth collaboration between design and development.
• Experience with UX writing to craft clear, engaging and accessible interfaces.
• Knowledge of UI/Visual design to craft beautiful and inclusive user interfaces.
• Contributions to open-source projects, thought leadership in the design community, or involvement in industry events or publications.

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: $120,00-$140,000 USD

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

• 401k 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 the country location(s) specified. 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.