Sendblue

iMessage for Sales

Senior Backend Engineer

$120K - $180K
Location
New York, NY, US / Remote (New York, NY, US)
Job Type
Full-time
Experience
3+ years
Visa
US citizen/visa only
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About the role

We’re looking for a Senior Node.js/React/PostgreSQL Engineer (New York) to join our team. You will own full-stack feature development, from database schema through backend APIs to polished React UIs, ensuring our platform remains fast, reliable, and SQL-driven as we scale.

Outcomes

  • Deliver high-quality production code across Node.js/Express backends and React frontends in a fast-paced startup setting.
  • Architect and optimize PostgreSQL databases: design schemas, write performant SQL queries, tune indexes, and ensure data integrity.
  • Build and iterate on user-facing React components—state management, hooks, and custom UI—for seamless customer workflows.
  • Design and implement robust RESTful and real-time APIs (WebSockets) to connect your React apps to scalable backend services.
  • Collaborate with product, design, and support teams to translate customer feedback into features that drive business efficiency.
  • Improve system observability—logging, metrics, alerting—to detect and resolve performance bottlenecks in both front- and back-end layers.
  • Participate in sprint planning, own technical stories, and help refine processes to boost team velocity and code quality.

Competencies

  • 4+ years professional experience building end-to-end systems with Node.js and Express.
  • Deep expertise in React (hooks, context, performance optimization) and modern frontend tooling.
  • Mastery of PostgreSQL: schema design, complex JOINs, window functions, stored procedures, and query optimization.
  • Strong grasp of system design: microservices, event-driven patterns, caching strategies.
  • Excellent debugging and troubleshooting skills across the full stack.
  • Clear communicator—able to explain technical trade-offs to engineers, designers, and stakeholders.
  • Bias for action—comfortable shipping quickly without compromising on stability or maintainability.

Bonus Points

  • Familiarity with Next.js, TypeScript, or GraphQL.
  • Experience with containerization (Docker) and orchestration (Kubernetes).
  • Prior work in real-time messaging or event-streaming architectures.
  • Hands-on knowledge of CI/CD pipelines, automated testing, and code review best practices.
  • Previous startup experience, especially in high-growth environment

About the interview

Tell us your understanding of our technical challenges and how your experience with Node.js, Express, and PostgreSQL can help us overcome them. We’re eager to learn how you can contribute to both our rapid shipping velocity and our commitment to high-quality, SQL-driven backend systems.

If you’re passionate about building robust backend architectures and optimizing SQL-driven systems, we’d love to hear from you.

About Sendblue

Sendblue lets businesses send iMessage from inside their CRM.

When it comes to sales, authenticity is everything, and green bubbles aren’t cutting it anymore. In order to get a lead with an iPhone to actually respond to a text in 2025, it HAS to be blue. That’s where Sendblue comes in – we provide a virtual iMessage line directly in a business’ CRM which they can use to message their leads and clients.

Our goal is to provide an over the top experience for our customers in every way, from giving them technology they can’t access anywhere else to ensuring their workflows and sales processes are actually effective. We deeply value the relationships we have with our customers, and keeping them happy and successful is our top priority. We are a lean team based in New York City, and we are growing extremely quickly.

Sendblue
Founded:2023
Batch:S23
Team Size:35
Status:
Active
Location:New York
Founders
Rob Haber
Rob Haber
Founder
Alex Luis
Alex Luis
Founder