Senior Full-stack Engineer (NYC)

Senior Full Stack Engineer

Crossmint is the leading enterprise-grade, all-in-one stablecoin and wallet infrastructure platform enabling fintechs and enterprises to integrate stablecoin rails and smart wallets with speed, compliance, and scale. Trusted by more than 40,000 clients including global leaders such as MoneyGram, WireX, Toku, and more, Crossmint provides embedded smart wallets, on/offramps, cross-chain stablecoin orchestration, tokenization, and other blockchain primitives through simple, developer-friendly APIs that integrate in minutes and scale to millions of users.

We're looking for a Senior Full Stack Engineer to own critical pieces of our Web3 infrastructure, from payments systems and digital wallets to minting frameworks and decentralized applications. You'll work across the entire stack, building advanced APIs, distributed backend services, and front-end interfaces that power next-generation blockchain products.

If you want high ownership, hard infrastructure problems, and a seat at the table for technical direction, this is the role.

What You Will Do

• Designing and delivering secure, scalable crypto and Web3 systems, with deep ownership of payments infrastructure, digital wallets, minting frameworks, and decentralized applications.
• Building advanced APIs, distributed backend services, and complex front-end interfaces that drive next-generation user experiences across blockchain-enabled products.
• Leading architectural decision-making for new features and core systems, collaborating with Product and Engineering teams to align design choices with long-term technical and business strategies.
• Establishing technical standards for full stack development, promoting best practices around performance optimization, security, reliability, and maintainability.
• Mentoring junior and mid-level engineers through code reviews, technical deep dives, and informal coaching to elevate overall team expertise.
• Optimizing production systems by profiling and debugging large-scale distributed applications, improving system performance, and enabling higher throughput and availability.
• Writing technical documentation and contributing to knowledge-sharing efforts to support rapid scaling and long-term sustainability of the codebase.
• Driving end-to-end technical design reviews and making critical architectural decisions that balance scalability, security, and long-term maintainability across multiple products.
• Conducting in-depth performance profiling, threat modeling, and security audits of decentralized applications and smart contracts to ensure robustness at scale.

What We Are Looking For

Must-haves

Bachelor's degree or foreign equivalent in Computer Science or a related field, and three years of experience in the job offered, or in a Software Engineer, Software Developer, Computer Programmer, Systems Analyst, Application Developer, Web Developer, or related occupation.

Alternatively, we will accept a Master's degree or foreign equivalent and one year of experience in the job offered, or in a Software Engineer, Software Developer, Computer Programmer, Systems Analyst, Application Developer, Web Developer, or related occupation.

We require at least one year of experience in the following:

• TypeScript: Designing scalable, production-grade full-stack applications and decentralized application interfaces, including high-performance React integrations.
• Developing resilient backend systems using Nestjs, APIs, and services, including blockchain data processing with Temporal workers, distributed task orchestration, and real-time event handling.
• Building, testing, and deploying Solidity smart contracts in production environments, ensuring compliance with security standards and gas optimization best practices.
• Designing and maintaining blockchain infrastructure components such as indexers, event listeners via webhooks, and data pipelines for hybrid on-chain/off-chain systems.
• Delivering highly reliable, maintainable production code with measurable improvements in scalability, uptime, and performance across distributed systems.
• Designing and deploying monitoring, observability, and fault-tolerant solutions to ensure system resilience at scale.

Benefits

• Extensive access to leading AI tools and subscriptions, with AI actively encouraged and integrated into daily workflows.
• Stock options program.
• We conduct two performance reviews annually. The first addresses performance ratings, bonuses, and promotions. The second encompasses these elements along with salary adjustments reflecting inflation and market conditions.
• Unlimited, flexible PTO.
• Flexible work schedule.
• Company laptop and allowance for any necessary home equipment.
• Daily stipend for commuting to the office.
• Company-paid trips for annual off-sites and onsites.
• Insurance covered by Crossmint.
• 401(k) Plan.

Our Principles

• Results and delivery: Ship high quality work fast.
• Build for the long term: Build scalable, secure, and reliable solutions. Use AI.
• Extreme Ownership: Be an effective Directly Responsible Individual (DRI). Be proactive.
• Be a team player: Be an effective and kind colleague providing credible challenge. Be present and reliable.

Talent research indicates that women are often less inclined than men to apply for a role unless they have experience in 100% of the listed skills. However, this list is only a guide. We welcome your application even if you feel you meet around 75% of the requirements. At Crossmint, we believe skills can be learned, and diversity makes us stronger.

We work to foster a respectful environment where each person can be their authentic self, free from harassment, racism, and any form of discrimination. We proudly uphold our commitment to diversity and inclusion as an equal opportunity employer, and this policy applies to all employment practices within our organization.

Please note that Crossmint never conducts AI-based interviews, and all of our processes include an initial video call with a team member. Crossmint will not request your personal identification documents or any payment at any point during your interview process.

Please stay vigilant about potential fraud. If you receive an email that claims to be from Crossmint but ends with any domain other than @crossmint.com, @crossmint.io, or @paella.dev, it is not from us. We own these three domains listed before, and they are the only legitimate ones.

Please let our Talent Team know if you need any assistance completing any forms, or participating in the process.

Our People Ops team will be joining you throughout the entirety of the interview and onboarding processes. Feel free to reach out if you need anything!

• Adolfo Fernández - Recruitment & People Ops
• Gloria Alogo - People Ops, Onboarding & Benefits

Please note that these are the only members of our People Ops team. Please remain vigilant and watch out for impersonators.