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Senior Backend Engineer (Platform and API)

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Buffer

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Contract Type:
Not provided

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Salary:

156500.00 - 202300.00 USD / Year

Job Description:

We're looking for a senior backend engineer to join the Channels and Platform team at Buffer. You will play a key role in building our public API and creating a future plug-in ecosystem that would elevate Buffer into a platform other developers can build on top of, providing creators the next generation of tools for writing, editing, and managing content.

Job Responsibility:

  • Be part of a small, dedicated squad within the Channels and Platform team responsible for Public API development
  • Lead the development of the backend systems for the Buffer Platform. This includes creating an API for core Buffer features, internal services to ensure Public API stability, availability, high performance, and developer tools for platform clients
  • Improve and evolve our internal systems — helping consolidate services into a monorepo, improve tooling and observability, and reduce complexity across the board
  • Collaborate closely with engineers, product, and design to scope work, explore trade-offs, and find the simplest path to something great
  • Make steady improvements to performance, reliability, and data modeling, helping us scale quality over time
  • Participate in on-call rotation (all engineers take on a 24/7 week-long shift once a quarter on average) and day-to-day maintenance work required to keep the lights on the systems owned by the team (this includes bug fixing, addressing security vulnerabilities, incident follow-ups, etc.)
  • Contribute to shaping our engineering culture by sharing knowledge, reviewing code, and leading by example

Requirements:

  • You have practical experience designing, implementing, and maintaining public APIs, plug-in ecosystems, or extensibility platforms
  • You have deep experience with modern stack — we use Node.js, TypeScript, GraphQL, and MongoDB
  • You’ve led backend projects from start to finish — shaping architecture, guiding trade-offs, and delivering reliable systems that support real-world product needs
  • You have strong systems thinking. You look beyond the immediate task, anticipate downstream effects, and help teams converge on architecture that supports the long game
  • You’ve worked across teams to drive platform or infrastructure improvements — whether simplifying service boundaries, improving observability, or evolving internal tooling
  • You’ve contributed to collaborative or multi-user product features, and you understand the data, consistency, and UX considerations that come with them
  • You’re fluent with modern AI tools — not just using them for code generation, but integrating them into how you debug, document, explore ideas, and reduce manual effort
  • You care about performance, scale, and clean abstractions — and know how to measure, prioritize, and improve them pragmatically
  • You’ve influenced engineering culture through code reviews, mentoring, or leading by example, and you’re comfortable being a resource for others on architectural decisions
  • You have a personal stake in the world of content creation
  • maybe you’ve run a newsletter, built an audience on social media, or regularly shared your own work online. You’ve used Buffer before and care about the experience of planning, creating, and publishing content
  • You thrive in remote, async environments. You’re clear in your thinking, generous with context, and don’t wait for perfect information to get started
  • You’ve likely been doing this for 7+ years, but experience depth and impact matter more to us than a specific number
What we offer:
  • Competitive salary
  • Work remotely
  • 4-Day workweeks
  • Health insurance
  • Home office setup
  • Growth mindset fund
  • New laptop
  • Unlimited free books
  • AI tools stipend
  • Flexible time off
  • Savings plan
  • Profit sharing
  • Family leave
  • Family support fund
  • Working smarter stipend
  • Sabbaticals
  • Offers Equity

Additional Information:

Job Posted:
December 06, 2025

Employment Type:
Fulltime
Work Type:
Remote work
Job Link Share:

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