Source Job

• Design, build, and maintain scalable distributed backend systems powering platform and product capabilities.
• Own backend services end-to-end, from architecture to monitoring, while collaborating with product and engineering peers.
• Build and evolve Web3 platform backend components, including protocol integrations and blockchain network support.

Zerion builds backend systems for Web3 infrastructure, powering API and wallet products trusted by 50+ top crypto brands. They have a fully remote team with strong ownership and high code quality, processing over 3.1B requests and supporting 1.7M+ active funded wallets.

• Design and implement low-latency backend systems and APIs for quoting, hedging, and executing across on-chain and traditional trading venues.
• Collaborate with the trading team to define interfaces and workflows between pricing, execution, and market data services.
• Build reconciliation and data-integrity tooling to ensure positions, fills, and PnL consistency across live trading state.

Ondo Finance provides institutional-grade, blockchain-enabled investment products and services, with a technology arm developing DeFi and an asset management arm creating tokenized funds. They are a well-capitalized, fully remote team with members across the U.S., backed by top investors.

• Design and build backend services in Rust for high-volume financial transactions with strong guarantees.
• Own features end-to-end, from spec to production, and set technical direction for your area.
• Integrate with external partners and improve engineering quality across observability and security.

MoonPay builds the operating system for value movement, enabling enterprises to fund, tokenize, trade, and spend digital assets. With top rankings in Fortune's Crypto 100 and Forbes' Best Startup Employers, they foster a high-velocity, high-accountability culture.

• Own key architecture and technical decisions across backend systems to ensure scalability, reliability, and performance.
• Build and operate real-time data pipelines handling order book updates, trades, and market events.
• Design, develop, and maintain API infrastructure including GraphQL and WebSockets, and optimize PostgreSQL, Redis, and ClickHouse for high-volume trading data.

They build infrastructure for decentralized financial markets, powering real-time trading and data pipelines for products used by hundreds of thousands of traders. They are a high-growth, remote-first team that values technical excellence, collaboration, and significant ownership in a fast-paced 0-to-1 environment.

• You'll contribute to infrastructure scaling to infinitely many apps, improving performance and reliability across backend services.
• You'll support observability efforts, help implement SLOs, and build foundational services for next-generation cloud infrastructure.
• You'll participate in triage and on-call processes to diagnose issues and implement changes to prevent recurrence.

Bubble is an AI visual development platform that empowers anyone to create software without code, from first-time entrepreneurs to enterprise teams. With over 6 million users in more than 100 countries and a mission to break down barriers to entrepreneurship, the company fosters a collaborative and inclusive culture focused on empowering builders worldwide.

• Implement and manage the infrastructure stack to enable the engineering team to ship quickly and effectively.
• Proactively identify and eliminate bottlenecks in the devops process to ensure optimal developer velocity.
• Maintain Tempo chain reliability, validator infrastructure, and explorer reliability.

Tempo is a layer-1 blockchain purpose-built for stablecoins and real-world payments, born from Stripe and Paradigm. They are a team of crypto-optimists building infrastructure for onchain payments.

• Design and build scalable backend systems, APIs, and data models that power communications, experimentation, and personalization.
• Partner with Product, Data Science, and Experience teams to define and execute strategies for customer acquisition and engagement.
• Mentor and support junior engineers, contributing to a culture of learning, collaboration, and technical excellence.

Affirm is a financial technology company that provides point-of-sale installment loans to consumers, allowing them to pay over time with no hidden fees. The company is remote-first and values transparency, care, and flexibility, with a strong emphasis on employee well-being and professional growth.

• Design highly reliable services capable of handling significant traffic fluctuations.
• Monitor backend performance, identify bottlenecks, and implement effective optimizations.
• Collaborate with cross-functional teams to solve complex technical challenges.

We are a leading global blockchain ecosystem behind the world’s largest cryptocurrency exchange by trading volume and registered users. We are trusted by 300+ million people in 100+ countries and have a flat, innovative culture that values collaboration and autonomy.

• Own backend solutions end to end, from problem definition through production.
• Design and evolve services for performance, scale, resilience, and data integrity.
• Work closely with product and engineering colleagues to turn complex requirements into simple, durable solutions.

Trading212 enables everyone to build wealth by reinventing trading and investing through exceptional products. They serve over 6 million clients with over €38 billion in assets, fostering a culture of high standards, high velocity, and ownership.

• Design and build scalable backend services and APIs for LaunchDarkly's Experimentation product.
• Own backend components from discovery through monitoring and continuous improvement.
• Collaborate with cross-functional teams to translate customer needs into reliable technical solutions.

LaunchDarkly is a feature management platform that helps developers release software faster and safer. The company fosters a collaborative, respectful, and inclusive culture with a focus on team empowerment.

• Build and maintain backend services for our LLM gateway, including routing, rate limiting, and observability.
• Contribute to sandboxing and isolation infrastructure for safe agent-generated code execution.
• Write high-performance backend code in Go, Rust, or async Python, supporting Kubernetes-based platform services.

AZX accelerates positive impact in critical industries through AI transformation. Founded in 2024 and profitable from the start, we work with category leaders in real estate, energy, logistics, and utilities.

• Design and build highly scalable distributed systems to support global expansion across multiple countries and regulatory environments.
• Partner closely with product, operations, payments, logistics, and platform teams to own critical operational and transactional systems.
• Work on cross-border transaction infrastructure, tax and regulatory compliance, international post-purchase experiences, and marketplace operational tooling.

Whatnot is the largest live shopping platform in North America and Europe, enabling sellers to build businesses across hundreds of categories. They are a remote co-located team with hubs across the US, UK, Ireland, Poland, Germany, and Australia, and were recently named the #1 Best Startup Employer in America.

• Own and evolve the core platform, including data model, APIs, and services.
• Design and build backend systems for portfolio intelligence, including data aggregation and analysis at scale.
• Build and maintain integrations with customer tools and make architectural decisions for growth.

Dragonboat provides an AI platform for Strategic Product and Portfolio Management, trusted by enterprises globally. It is a venture-backed, fast-growing SaaS startup with remote teams in Portugal and the US.

• Own backend solutions end to end, from understanding business problems to production deployment.
• Design and evolve services for performance, scale, resilience, and data integrity.
• Diagnose production problems, address root causes, and share knowledge across the team.

Trading212 enables everyone to build wealth by creating exceptional trading and investing products. Serving over 6 million clients with more than €38 billion in assets under management, the company values high standards, high velocity, and engineering ownership.

• Own and deliver quarterly goals for your team, leading engineers through ambiguity to solve open-ended problems.
• Support peers and stakeholders in the product development lifecycle by collaborating with product management, design, and analytics.
• Foster a culture of quality and ownership by setting code review and design standards, and developing talent on your team.

Affirm is a financial services company that provides buy now, pay later financing without hidden fees or compounding interest. They have millions of customers and thousands of merchant partners, and foster a culture of honesty, trust, and innovation.

• Design, develop, and launch backend systems at scale using Python or Kotlin.
• Collaborate with team and stakeholders to balance speed and quality while protecting system reliability.
• Contribute to community through growth and development activities and navigate large codebases.

Affirm is reinventing credit to make it more honest and friendly, giving consumers the flexibility to buy now and pay later without hidden fees. They are a remote-first company that values transparency and employee well-being, offering competitive benefits and a collaborative culture.

• Co-own the MaaS system design as the deepest backend voice, driving architectural decisions and setting engineering standards.
• Build a globally distributed, multi-tenant token service with high throughput, reliability, and observability.
• Own end-to-end implementation, from code to migrations, ensuring zero-downtime upgrades and strict SLOs.

Bitdeer is a world-leading technology company for AI and Bitcoin mining infrastructure, providing comprehensive Bitcoin mining solutions and AI computational infrastructure. Headquartered in Singapore, it has deployed data centers across the United States, Norway, Bhutan, and Ethiopia, and is committed to equal employment opportunities.

• Lead cross-cutting initiatives and drive modular backend architecture to improve scalability and developer velocity.
• Set standards for APIs, testing, security, and operability while mentoring engineers and shaping technical direction.
• Own production systems, participate in on-call, and lead AI-assisted engineering workflows with quality and safety guardrails.

GitLab is the intelligent orchestration platform for DevSecOps, helping organizations increase developer productivity and improve operational efficiency. With over 50 million users and trust from more than 50% of the Fortune 100, GitLab fosters a high-performance culture driven by values, continuous knowledge exchange, and AI integration.

• Write reliable, secure, and scalable code for Lithic's product platform with minimal tech debt.
• Improve system reliability and participate in team on-call rotation.
• Own projects from planning to launch, including API key management, audit logging, and search.

Lithic is a modern card issuing and processing platform for financial companies to build the future of payments. They are a team of 170+ across 26 states and 7 countries, with a remote-first culture.

• Set technical direction for backend development and design scalable, reliable web application systems.
• Architect and implement complex applications that apply ML techniques to large volumes of data.
• Balance customer-facing features and technical debt cleanup to keep the software suite sustainable.

Machinify is a leading healthcare intelligence company delivering unmatched value, transparency, and efficiency to health plan clients. Deployed by over 85 health plans, we bring together an AI-powered platform with best-in-class expertise, embracing complex challenges with curiosity and a high bar for engineering excellence.