About the job
About Us
Our mission is to revolutionize language learning.
Learning a new language can transform lives by providing access to diverse cultures, career opportunities, and communities. With two billion people globally striving to learn languages, the most effective method—one-on-one tutoring—remains difficult to access at scale and has not evolved significantly over the years. Speak is developing an AI-powered, human-like tutor that fits in your pocket, offering a conversation-first approach that allows learners to practice speaking, receive immediate feedback, and progress through thoughtfully designed lessons. This results in a comprehensive journey from novice to confident speaker across multiple languages.
Since our launch in South Korea in 2019, Speak has emerged as the leading language learning app, now available to learners in various markets and over 15 languages. As one of the foremost AI companies globally, we have secured over $150 million in venture capital from notable investors such as OpenAI, Accel, Founders Fund, and Khosla Ventures, with a diverse team spread across San Francisco, Seoul, Tokyo, Taipei, and Ljubljana.
About This Role
We are seeking a Senior Backend Engineer, with full-stack capabilities, to help create innovative AI-driven product experiences. The ideal candidate should have experience collaborating closely with product, design, and machine learning teams, alongside a proven track record in developing polished consumer applications. This role is pivotal in shaping our latest products focused on programmatic, conversational language learning and will significantly impact the future direction of our company.
Your Responsibilities
- Crafting innovative AI-driven product experiences and user interfaces for the web.
- Full-stack engineering with a primary focus on designing scalable backend systems.
- Troubleshooting complex streaming challenges.
- Taking ownership of the complete development cycle of features from ideation to production.
- Writing code efficiently, shipping frequently, and making a substantial impact on our business by facilitating the scaling of our content.
Your Profile
- 5+ years of industry experience as a Backend Engineer, ideally within a fast-paced startup environment.
- Bonus: Experience on an app that has reached over 1 million users.
- Exceptional problem-solving and communication skills, along with the ability to work effectively in a collaborative environment.

