At Ephemera, we're building the future of private, decentralized messaging.

We're helping grow the XMTP ecosystem through infrastructure R&D, and we’re developing a secure, encrypted, crypto-native messaging app.

We believe in building with XMTP because:

• Privacy is essential to protecting our communication

• Interoperability breaks us free from the closed silos of today

• Decentralization enables innovation without gatekeepers

• Data ownership means your messages belong to you — not big tech

• Permissionless access ensures control and opportunity for everyone

This is why we’re building XMTP and our messaging app.

Our mission is ambitious: to create foundational technology for the next layer of the internet — a secure, decentralized messaging protocol that’s built to last, and an encrypted app that makes using crypto as easy as sending a message.

Everything we do is open source, because trust starts with transparency. We’re building XMTP and the tools around it in the open, to support a global developer ecosystem.

We are Ephemera — and we’re building the messaging layer of the future.

We're looking for a Staff Software Engineer (React Native Application) who will play a critical role in designing, building, and optimizing our React Native iOS and Android mobile applications.

You’ll bring a deep passion for building seamless, high-quality mobile experiences and thrive on tackling complex technical challenges in collaboration with a small, high-impact team. This role offers the opportunity to contribute to open-source projects and shape the future of onchain messaging.

What You’ll Be Working On

• Building and maintaining high-quality, production-grade consumer mobile applications with React Native with a very high bar for quality, performance, and a focus on impact.

• Collaborate with staff engineers and partners across the organization to ensure technical agreement to other systems, products and vision.

• Use your technical expertise to constantly improve and ensure your team achieves extraordinary results at the high technical level we set.

• Advise the leadership team on essential technical considerations related to ensuring engineering excellence and successful high impact key initiatives.

• Stress-testing our React Native SDKs by developing and benchmarking production-grade applications.

Your Experience

• Minimum of 7-10 years of professional experience building production-grade mobile applications at scale.

• Ability to technically lead a team of high quality engineers and communicate progress clearly to leadership.

• Advanced proficiency in React Native app development is a must.

• Knowledge of Swift and Kotlin for effective iOS and Android development.

• Has built an app frame scratch to scale.

• Experience working in open-source projects and collaborating with external developers.

• Familiarity with web3 development or messaging technologies is highly desirable.

Nice-to-Haves

• Experience with peer-to-peer or instant messaging systems and protocols.

• Prior involvement in open-source projects and public communication.

• An eye for design, ensuring pixel-perfect alignment and excellent user experiences.

About You

• You are passionate about decentralized technology and believe in an onchain future.

• You love to win and are fueled by solving hard problems.

• You are self-directed, see opportunities, and are inspired by challenges and helping solve them.

• You can reduce ambiguity and take action to unblock yourself independently.

• You thrive in a small team environment and focus on where you can have the greatest impact.

• You love to learn, embrace change, and are open to new ideas and feedback.