Kotlin Jobs in Web3

Who We Are

Solana is a high-performance blockchain that can deliver a fast and friendly user experience, without sacrificing security.

Solana Labs, Inc. ("Solana Labs") is a technology company that builds products, tools, and reference implementations that can be used on the Solana blockchain.

Senior Backend Engineer - Solana Mobile

Location: Remote (US or EMEA time zones) Type: Full-time Level: Senior IC

About Solana Mobile

Solana Mobile is building the mobile platform for digital assets on Solana. We recently launched Seeker, a digital asset–first phone featuring Seed Vault, a hardware-backed security system for wallets, along with our own wallet and the dApp Store, a mobile distribution platform for apps built by the ecosystem of Solana developers, and the Solana Mobile Stack (SMS), which enables phone manufacturers to deliver these products on their own devices.

We don't just provide infrastructure. We build the full stack across hardware, software, and platform services to deliver seamless, secure, and performant digital asset experiences on mobile.

Our backend systems power the dApp Store, wallet services, event tracking, both on-chain and within apps, on-chain transaction systems such as staking, and the APIs that developers and users rely on every day.

The Role

We're a lean, high-agency team. Engineers here own real scope: there's no large org to absorb the slack, and the decisions you make show up directly in the product. That also means we move fast and expect people to operate with a high degree of autonomy.

We actively lean into AI-assisted development as a way to keep overhead low and give every engineer more leverage. That's not specific to any one role, it's how we work. We expect engineers to experiment with AI tools, integrate them into their own workflows, and share what works. A lot of what makes us effective is how we work, and there's meaningful room to improve.

If you write solid backend systems, take ownership seriously, and want to work in an environment where your contributions have a real impact, this is it.

What You'll Own

• Design and own backend architecture for core Solana Mobile services: dApp Store APIs, wallet services backend, device registry, event tracking, and on-chain activity systems (staking and related infrastructure)

• Build and maintain REST and WebSocket APIs consumed by Android, Flutter, and Web clients, as well as third-party developers integrating the Solana Mobile Stack

• Own your services in production: participate in on-call rotation, author runbooks, contribute to post-mortems, and close the loop on action items

• Look for friction in your own work and in the team's processes: automate what makes sense, build small tools that save repeated effort, and share what you build

• Contribute to CI/CD reliability and build infrastructure (GitHub Actions, WarpBuild) with a sharp eye on pipeline speed, cost, and reproducibility

• Conduct thorough code reviews, contribute to technical discussions, initiate RFC discussions for significant changes, and help the team get better over time

• Drive infrastructure decisions on AWS (ECS, RDS, Lambda, SQS, CloudFront) — from architecture through to cost-conscious production operation

• Own the observability stack: structured logging (Loki), metrics and alerting (Prometheus, Grafana Unified Alerting), distributed tracing, and incident response runbooks

• Contribute to backend architecture for device attestation and the Seed Vault integration layer, including on-chain verification flows (Squads Protocol multisig, SPL token operations)

• Collaborate with mobile engineers (Android/Kotlin, Flutter/Dart) to design mobile-first API patterns — offline resilience, background sync, efficient payloads for constrained networks

• Work closely with Protocol Engineers, building Solana programs to design off-chain services that compose cleanly with on-chain logic

What We're Looking For

• 5+ years of professional backend engineering, with a track record of owning and operating production services

• High ownership: you take problems end-to-end and drive them to resolution without waiting for direction

• Proactive by default: you identify issues early, propose solutions, and move quickly

• You already use AI coding tools (Claude Code, Cursor, Copilot) as part of how you work: not as a novelty, but because they make you faster and you've figured out when to trust them

• Strong proficiency in TypeScript/Node.js and/or Rust — idiomatic, well-tested, production-grade code

• Solid command of PostgreSQL: schema design, query optimization, indexing, migration discipline

• Good working knowledge of Redis: caching patterns, pub/sub, TTL strategies

• Hands-on AWS experience: ECS, RDS, SQS, S3, Lambda — comfortable deploying and operating services in a cloud environment

• Sound understanding of distributed systems: idempotency, eventual consistency, fault tolerance, graceful degradation

• Security-aware: secrets management (AWS Secrets Manager / SSM), API auth patterns (JWT, OAuth2), OWASP hygiene

• Comfortable with Docker and containerized deployments

Bonus points:

• Familiarity with the Solana ecosystem: RPC node interaction, on-chain program invocation, SPL tokens, wallet adapter patterns, or indexer design

• Experience working closely with external developers or ecosystem partners: debugging integrations, reviewing SDK usage, or shaping APIs based on real developer feedback

• You've built small automation scripts, internal tooling, or LLM-integrated workflows that saved real time, for yourself or your team

• Experience building backends for mobile-native products (push notifications, storefront APIs, device attestation, background job orchestration)

• Contributions to open-source backend libraries, developer tooling, or the Solana ecosystem

• Prior experience in a senior or tech lead capacity: driving cross-team alignment, writing technical specs, owning a domain end-to-end

Our Stack

TypeScript · Rust · Node.js · PostgreSQL · Redis · AWS (ECS, RDS, Lambda, SQS, S3) · Docker · GitHub Actions · WarpBuild · Grafana · Prometheus · Loki · Solana Web3.js · Squads Protocol · SPL · AWS Secrets Manager · Android/Kotlin · Flutter/Dart