Backend Engineer

About

• We're building the future of storytelling and video editing.
• We're a small team that moves fast and builds things we're proud of.
• We care obsessively about taste: in design, in product, in every detail.
• We're solving these hard problems.
• We're backed by a Tier-1 global fund, YC, and founders of billion dollar companies.

Engineering

Video is the most powerful way humans tell stories. It always has been. But creating it today is still painfully hard. Fragmented tools, steep learning curves, and workflows that get in the way of the actual creative work. We're building Cardboard to change that.

Cardboard runs a real video editor in the browser. That only works because of a serious backend: proxy transcodes so 4K footage plays smoothly, a fan-out export pipeline that renders chunks in parallel, analysis workers that understand what's on screen, and an agent service that turns natural language into timeline operations.

We're hiring a Backend Engineer to own those systems. You'll design services, job flows, and data models that stay fast and correct under messy real-world media: huge files, flaky uploads, GPU workers, and users who expect progress in seconds, not minutes.

You'll be working alongside a team of engineers who all care deeply about craft, including the founders. You like owning problems end to end, and you'd rather ship something great this week than something perfect next quarter.

What you'll actually do

• Own backend systems for exports, proxies, media preprocessing, analysis, and agent-powered editing.
• Maintain the APIs and state contracts between the browser, workers, storage, and database.
• Improve long-running media workflows: uploads, exports, processing jobs, progress, and recovery.
• Keep the backend simple enough to operate as projects, files, and usage grow.
• Solve these hard problems.

Who you are

• You've owned production backend systems and kept them healthy as the product changed.
• You think clearly about state, queues, workers, files, and the contracts between them.
• You can turn product goals like faster exports or instant-feeling uploads into a practical backend plan.
• You care about media: formats, codecs, model output, processing time, and the final quality users see.
• You're language-flexible. TypeScript, Go, Rust, Python: you'll use whatever fits the problem.
• Bonus: deep FFmpeg or GStreamer experience, or codec internals knowledge across formats like ProRes, H.264/H.265, BRAW, R3D, DNx, and others.

What you get

You'd be surrounded by people who are absurdly good at what they do. One started coding at 11 and shipped an app with 6M+ downloads in high school. One got into CS engineering at 14 and has been working on distributed systems for 8+ years. One's an ex-founder who took a company to 1.2M users and $300M+ in transactions. That's the team. We're looking for someone who'll raise the bar on technical craftsmanship and product quality. Apart from that you'd get:

• Competitive salary and founding-team equity.
• Unlimited tokens across every AI model. Use whatever you want, as much as you want.
• A healthy budget for AI tools and any peripherals you need to do your best work.