Senior Backend Engineer

Speak
San Francisco, CA

About us

Our mission is to reinvent the way people learn, starting with language. We begin by teaching the next billion people English, Spanish, and French.

English is the global language of business, culture, and communication, and over 1.5 billion people around the world are actively trying to learn right now. Others dream of communicating with the half-billion native Spanish speakers across the globe. The problem is that it's nearly impossible to learn to speak a language without constant access to a speaking partner. Grammar and vocab apps don't really help – you need to actually converse with someone.

Speak is on a journey to fix this. We're creating an AI-powered experience that replicates the flow of a conversation, without needing a human on the other end. The goal is to make it radically more accessible to be able to have conversations in a foreign language and eventually help hundreds of millions of people gain fluency who otherwise wouldn't be able to.

We started on this journey over five years ago and we've still got a long ways to go. We're thoughtfully adding new team members only when we think they can truly play a big role in our mission.

Speak launched first in South Korea where we have quickly grown to become the top grossing education app in the country. We have now delivered this winning product to more than 40 countries globally and are continuing to expand to more markets in the coming months. The company is well funded, and as of December 2024, we've reached a $1B valuation with our Series C round, through key partners like Accel, OpenAI, Founders Fund, Y Combinator, Khosla Ventures, Lachy Groom, Josh Buckley, and more. We’re a team of more than 90 based throughout San Francisco, Seoul, Tokyo, Taipei, and Ljubljana.

About this role

We are looking for a senior backend focused but full-stack capable engineer to work on building novel AI-powered product experiences. The ideal candidate will have experience working in close coordination with product, design, and machine learning teams, as well as have a background in building polished consumer applications. This role sits at the center of developing our newest products focused on programmatic, conversationally-driven language learning and will be an instrumental contributor to the future of our company.

What you'll be doing

  • Building novel AI-driven product experiences and user interfaces on the web

  • Full-stack engineering, but focused on creating scalable backend systems.

  • Debugging complex streaming issues.

  • Owning the entire development cycle of features, from conception to production

  • You'll be able to write code very quickly, ship frequently, and make a huge impact on our business by helping us scale our content

What we're looking for

  • 5+ years of industry experience working as a Backend Engineer, preferably in a fast-paced startup environment

    • bonus: worked on an app that has been used by 1M users

  • Excellent problem-solving and communication skills, and the ability to work independently or as part of a team

  • Coach and mentor other engineers

  • Strong product sense: ability to think broadly/cross-functionally about product experiences

Why work at Speak

  1. Join a fantastic, tight-knit team at the right time: we're growing very quickly, we've most recently raised our Series C from some of the top investors in the valley, and we've achieved product-market fit in our initial markets. You'd join at a magical time when a single person could significantly change the course of the company.

  2. Do your life's work with people you’ll love working with: we care strongly about our craft and want every person at Speak to feel like they're growing every day. We believe in the idea that working with people you both enjoy and have respect for makes everything better. We hire thoughtfully and only work with people we admire deeply.

  3. Global in nature: We're live in over 40 countries and launching in a number of new markets soon. We have dedicated offices in San Francisco, Ljubljana, Seoul, and Tokyo, and you’ll have the opportunity to talk to users in each of these regions on a regular basis as well as travel.

  4. Impact people's lives in a major way: Learning a language is one of the single most life-changing skills one can learn, and right now 99% of people never achieve their goal because the process is broken. We’re helping millions of people achieve their goals and improve their lives.

Speak does 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.

Posted 2025-11-25

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