Backend Software Engineer (Senior/Staff/Senior Staff)

Pittsburgh, PA 

Our mission at Duolingo is to develop the best education in the world and make it universally available. It’s a big mission, and that’s where you come in!

At Duolingo, you’ll join a team that cares about finding innovative solutions to complex technical problems, running countless experiments (300+ at a time!) with our massive user base to make data-driven decisions, and educating our users and employees alike. You’ll have limitless learning opportunities, mentorship and collaboration with world-class minds, and a variety of projects with large scopes — while doing work that’s both fun and meaningful. 

Join our life-changing mission to develop education for our half a billion (and growing!) learners around the world.

About the role

As a Backend Engineer, you will work on building the APIs that power our products and give our learners a best-in-class experience.

Our microservices infrastructure is composed of hundreds of endpoints serving hundreds of millions of requests per day. You will partner with your team members on identifying requirements and designing services that are fast, resilient, and cost-effective. You will have ownership over the entire lifecycle of your services and associated infrastructure, and ensure they are always operating well.

Below you can find more information about the teams we're hiring for:

Architecture Team: 

• The Architecture team’s mission is to ensure that Duolingo’s software continues to scale as we grow. We work on some of the largest and most critical infrastructure run by Duolingo and provide tools and best practice guidance to teams as they look to create new features and services. In this role, you will lay the groundwork for the future success of Duolingo’s software platforms.

DET Test Scoring Team:

• As an engineer on the Scoring team for the Duolingo English Test, you will help advance the state of the art in language testing. You will work closely with AI researchers and assessment scientists to pioneer innovative and AI-driven ways to assess language ability while maintaining critical infrastructure and strengthening the test’s reliability. You will advance the team’s mission to lower barriers and increase opportunities for English language learners everywhere.

DET Proctoring Operations Team:

• The Proctoring Operations team’s mission is to ensure that we provide high-quality and efficient human proctoring for all Duolingo English Test tests. In this role, you will take on full-stack web development work. You will primarily work on the ‘proctor portal’ an in-house tool used by contractors for proctoring the test. You will also work closely with the anti-cheating team to take new signals developed by them and put them in the hands of proctors.

Learning Scaling Area:

• The Learning Scaling Area’s mission is to ensure that all of Duolingo’s learners have access to high-quality educational content. We leverage pedagogical experts and AI to create content for over 100 courses. You will be responsible for building and improving the infrastructure and tooling that drives content creation.

Learning R&D Area:

• The Learning R&D Area works on improving the learning experience of our users with new bets, technologies, and features, that fill the learning gaps in our product. Our goal is to make Duolingo the best way to level up your language skills, regardless of your proficiency level.

Data Infrastructure Team: 

• As a Backend Engineer on the Data Infrastructure team, you will build tooling and infrastructure at scale to support Duolingo’s key data workflows from data visualization to A/B testing and AI.

Enterprise Applications Team:

• The enterprise application tooling team's mission is to provide tooling and engineering support for areas without traditional engineering support and for tools the entire organization leverages! We are responsible for the 2025 OKR “Pivot to tooling- and automation-first approach for People teamwork”. In this role, you will be utilizing generative ai, automation tools, and building DIY solutions to help improve the lives of employees across the organization!

 You will...

• Collaborate on software projects with product design and backend aspects
• Develop, release, and maintain backend services and/or infrastructure
• Lead individual project priorities, milestones, and ensure we're always shipping

 You have...

• A Bachelor’s degree in Computer Science or related technical field
• Strong competencies in data structures, algorithms, and software design
• Experience programming in Java, Python, or Kotlin
• Solid understanding of one or more database technologies

 Exceptional candidates will have...

• Industry experience building high-traffic APIs using public cloud providers

Take a peek at how we care for our employees' holistic well-being with our benefits here.

We will do everything we can within reason to make sure that your interview takes place in an environment that fairly and accurately assesses your skills. If you need assistance or accommodation, please contact your recruiter.

Duolingo is proud to be an Equal Employment Opportunity employer. We do not discriminate based upon race, religion, color, national origin, gender (including pregnancy, childbirth, or related medical conditions), sexual orientation, gender identity, gender expression, age, status as a protected veteran, status as an individual with a disability, or other applicable legally protected characteristics.

By applying for this position your data will be processed as per the Duolingo Applicant Privacy Notice.

We post a multi-level salary range for all of our roles.

This is not inclusive of the rest of our awesome portfolio that includes equity compensation and world-class benefits. Our salary ranges are the same for all US locations. Your recruiter can share more details about the range for a specific level during the hiring process. The actual salary within the range is determined by many factors including but not limited to, skills, experience, education, and internal equity.

Salary Range:

$148,800—$274,600 USD