Senior Full-Stack Engineer

About the RoleWe're hiring a Senior Full-Stack Engineer to help us scale our Platform Product, ship new API endpoints and Cal Atoms, and collaborate closely with our platform customers. This role is async by default, remote, and part of a company culture that prioritizes deep work, flexibility, and real ownership. For this role we are looking for people working in the US Timezone US, Latin America and/or South America are ideal locations.You'll work closely with our product and engineering teams and be trusted to take initiative, experiment, and ship high-impact software.What You'll DoBuild and maintain complex timezone logic, availability blocking, and calendar APIs Oversee the evolution of our Platform ProductCreate and ship Cal Atoms (frontend components)Develop new API endpoints for embedded use casesCollaborate with platform customers and internal teams to solve complex problems What We're Looking ForStrong experience building and maintaining APIs for long-term success Full-stack engineering skills, comfortable working across frontend and backend (TypeScript, React, NestJS, tRPC, Tailwind and Prisma)Ability to quickly understand and work on complex technical challenges High autonomy mindset — works well independently and collaboratively in a remote, async-first setup- Strong written communication (clarity > formality)Bonus SkillsPrevious startup or remote-first experience Familiarity with open-source contribution and our GitHub projectExperience in building platform products or developer-facing APIs How We Hire: The Lean Hire TrialWe approach hiring differently. Nearly all full-time roles at begin with a 30-day contract-to-hire trial, which we call a Lean Hire. This isn't a test to prove yourself; it's a mutual exploration. Think of it more like dating than interviewing.It gives you time to experience the culture, team, and work before committing It gives us a chance to ensure alignment without long-term risk on either side- Many of our strongest team members joined through Lean Hire and never looked backSuccess in a Lean Hire isn't about perfection; it's about curiosity, transparency, and seeing whether we thrive working together. Why Work at We're building not just as a product, but as a place to do great work and live a good life.Work from anywhere, anytime, fully remote & async Earn the same salary no matter where you liveNo standups, no micromanagement, no unnecessary callsReal flexibility, take time for life stuff, no approval neededWork in your own flow, pajamas welcome30 paid OOO days per year (wherever you are in the world) Yearly team retreats in beautiful locations- ‍‍‍ People-first culture, stable, family-friendly, kindWhat Our Team SaysAt this company, I'm actually treated like a real person with ideas and a life, not just another number in the system. It's refreshing to work somewhere that gets that happy humans do better work ~ Sean Brydon ( Software Developer)Working at Cal has been a completely different experience from other jobs I've had. There's real trust here - I've been able to take ownership of my work without being micromanaged. I started in support and quickly moved into a growth role because initiative is genuinely rewarded. Everyone communicates openly, and feedback is always encouraged. The async, remote culture has been a game-changer for me. I can structure my day around life: run errands and take breaks without the pressure of always being online. It's all about getting the work done. As a dad of two, that flexibility means everything. If I need to step away for my family, I can. That kind of trust and support motivates me to do my best work every day. ~ Milos Puac (Enterprise Triage Manager)