[Remote] Full Stack Engineer III

Note: The job is a remote job and is open to candidates in USA. Calendly is hiring a Full Stack Engineer III for its Trust & Safety team. The role builds and improves systems that prevent abuse, protect email and SMS deliverability and compliance, and support operational response to abuse.

Responsibilities

• Building and improving the systems that detect and stop abuse across sign-up, booking, and messaging, such as spam, phishing, bots, and fraudulent SMS traffic
• Improving the reliability, deliverability, and compliance of the email and SMS notifications Calendly sends
• Shipping new detection carefully: measuring how it performs on real traffic before it acts on accounts, and weighing false positives against false negatives
• Responding to active abuse, including during on-call, by stopping the damage fast, then replacing quick fixes with durable ones
• Building tools that help our Trust & Safety Operations team review accounts faster and understand why the system took each action
• Partnering with Product, Operations, and Data to define requirements and measure the impact of what we ship
• Working with other product teams to add protections to the flows they own
• Reviewing implementation plans and pull requests, and sharing what you learn with the team

Skills

• 3+ years of professional software development experience at a SaaS or technology company, including building and running production systems
• Strong backend skills: building services, APIs, and data-heavy workflows in a service-oriented architecture
• Experience with Rails, Node/TypeScript, Go, or a comparable language or framework, and a willingness to work across more than one
• Comfort with relational databases and SQL, and with using data to check whether a change actually worked
• An analytical, curious mindset: you think about how a system could be misused, not only how it's supposed to be used
• Good judgment about trade-offs, such as stopping bad actors without adding friction for real customers
• A commitment to clean, reliable, maintainable code, thoughtful testing, and shipping in small increments
• Clear communication with engineers and non-engineers alike, including Operations and Support partners
• Comfort and skill with AI tools in your engineering work, including reviewing their output critically
• Authorized to work lawfully in the United States of America as Calendly does not engage in immigration sponsorship at this time
• Experience in trust and safety, fraud, spam, or abuse prevention
• Experience with email or SMS delivery, such as deliverability, sender reputation, or messaging compliance
• Experience with bot protection, rate limiting, or third-party risk and verification services
• Experience building rules engines, risk scoring, or ML-backed decisions in production
• Experience using LLMs to classify or moderate user-generated content
• Experience with GCP, Kubernetes, PostgreSQL, or Redis

Benefits

• All full-time (30 hours/week) employees are also eligible for equity awards.
• Remote - US

Company Overview