Top Tech Jobs & Startup Jobs in Denver & Boulder, CO

Build and maintain developer tools, SDKs, CLI, MCP interfaces, integrations, and supporting backend services. Collaborate on API contracts, compatibility, testing, releases, documentation, and shared tooling. Support developers through GitHub issues and pull requests while designing reliable systems with authentication, retries, idempotency, rate limits, monitoring, and error recovery.

Build and operate reliable backend services for a developer-focused email platform. Responsibilities include owning features end-to-end, designing APIs and relational data models, scaling databases, building distributed systems with queues and background workers, managing AWS infrastructure, improving observability and deployments, participating in on-call, and partnering with customers and support to improve the product.

The Backend Engineer will build and maintain Resend's email transport infrastructure, focusing on SMTP delivery, routing, and system design for high-volume email sending. They will ensure the reliability and observability of the systems while participating in incident response.

Drive and scale a repeatable inbound enterprise sales motion: qualify high-intent leads, run experiments on playbooks, expand accounts, prevent churn, document learnings, and feed customer insights to product, marketing, and success. Remote role in the Americas with some travel for conferences and on-site meetings.

Provide front-line technical support for developer customers: debug and ship fixes, convert recurring issues into permanent solutions (docs, product changes, agent improvements), train and refine AI support agent, create guides, proactively build customer relationships, and advocate customer needs across the company.