Protocol Engineer (Convos)

XMTP Labs

40d•$225 - $265•Remote

About The Position

Build the messaging app you’ve always wanted — and shape the future of communication. We’re building Convos. It’s not your average chat app. We’re a small, experienced team with a big, meaningful mission. We are not going to talk you into joining a startup. To apply, simply share a link to a project you’re proud of. Can’t wait to meet you. Convos is secured by XMTP, an open-source, decentralized messaging protocol — the same messaging infrastructure securing World App, Base by Coinbase, Zora and thousands more projects. Because of Convos' unique product perspective, we have unique needs that vanilla, out-of-the-box XMTP does not yet meet. That’s your cue. In this role, you’ll develop and shape XMTP in ways that enable Convos to move forward quickly — and contribute to the network’s capabilities overall. The Convos protocol is a unique application of XMTP — you’re a cryptographically “new you” in every convo.

Requirements

10+ years of professional experience as a staff-level software engineer.
Expertise in mobile development with one or more of Kotlin, Swift, React Native, or C++, including delivering production-ready SDKs or apps.
Solid experience with Rust, or a strong interest in learning Rust and building Rust-to-mobile bindings.
Experience building and maintaining communication protocols, SDKs, or developer-facing APIs with an emphasis on performance, scalability, and security. A well-rounded, "T-shaped" expertise profile is preferred.
A proven aptitude for adversarial systems design, including identifying and mitigating potential security risks.
Prior involvement in open source SDK projects and public communications.
You’ve worked on a world-class consumer app team before
Taken products from concept to launch to scale
Experience leading technical projects and driving architectural decisions
Familiarity with API design, unit testing, and building maintainable codebases
Experience in open-source projects and collaborating with external developers
You reduce ambiguity. You unblock yourself.
You’re an excellent communicator, a team player, and “good in the room.”
You love a challenge. You aim to make an impact. You’re here to win.
You are always learning, embracing change, and open to new ideas and feedback.
You’re online 9–11AM PST (15:00–17:00 GMT)

Nice To Haves

Bonus points if you have prior experience with Messaging Layer Security.
Experience with large-scale distributed database systems.
Experience in implementing and adhering to security compliance requirements.
Interest in or prior experience with privacy-preserving cryptographic technologies, or with zero-knowledge cryptography.
Experience with smart contract development, web3 technologies, and/or protocol mechanism design.
Experience contributing to a Layer 1 blockchain.
Experience with messaging apps or protocols
Prior involvement in open-source projects

Responsibilities

Advance the encrypted XMTP messaging protocol (built on Rust and OpenMLS) to accelerate Convos product development and capabilities.
Collaborate with Convos and XMTP Labs teammates to design systems, evaluate trade-offs, and deliver improvements, balancing security, scalability, and efficiency.
Engage as an open source contributor, making intuitive changes that serve Convos and — by extension — empower the next generation of privacy-preserving apps.
Plan, design, build, test and maintain Convos app(s)
Execute consumer-grade product experiences — from performance to polish
Collaborate with experienced product, design and engineering teammates to efficiently produce effective products
Hold yourself and others to a high bar for quality and teamwork
Own communication, alignment and progress for your projects