--- title: "How Vercel Cut Build Wait Times From 90 Seconds To 5" url: https://daily.dev/posts/how-vercel-cut-build-wait-times-from-90-seconds-to-5-qbgsmgld2 source_url: https://blog.bytebytego.com/p/how-vercel-cut-build-wait-times-from type: article source: "ByteByteGo" published: 2026-05-26T15:33:12.797Z updated: 2026-05-26T15:33:39.146Z tags: ["vercel", "multi-tenancy", "build-systems"] reading_time: 13 upvotes: 1 comments: 0 language: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # How Vercel Cut Build Wait Times From 90 Seconds To 5 **[ByteByteGo](https://daily.dev/sources/bytebytego)** · 13 min read · 1 upvotes · 0 comments ## Summary Vercel's internal build platform, codenamed Hive, reduced build provisioning time from 90 seconds to 5 seconds (an 18x improvement) by adopting Firecracker microVMs instead of standard containers. The core problem was hostile multi-tenancy: customer build scripts run on shared hardware and could be malicious, making container-level isolation insufficient. Firecracker provides VM-level kernel isolation while booting in ~125ms. Three stacked optimizations drove the speedup: local caching of build container images (saving ~45s), a warm pool of pre-booted cells that eliminates cold-start latency for most builds, and Firecracker's inherently fast boot times that make warm pools practical at scale. Each cell is destroyed after every build to prevent state leakage between customers. The architecture also enabled product features like enhanced build machines and Secure Compute for enterprise customers. The tradeoff is significant engineering investment and ongoing compute costs for idle warm-pool cells. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [How We Made Docker Builds 193x Faster: From 45 Minutes to 14 Seconds](https://daily.dev/posts/how-we-made-docker-builds-193x-faster-from-45-minutes-to-14-seconds-de7etgu0z) · HelixML · 78 upvotes · 1 comments - [Your Container Is Not a Sandbox](https://daily.dev/posts/your-container-is-not-a-sandbox-dkskd3kl8) · Lobsters · 26 upvotes · 1 comments - [Counting to 3 with a new builder processing 50M\+ monthly builds](https://daily.dev/posts/counting-to-3-with-a-new-builder-processing-50m-monthly-builds-uvavj2xjm) · Railway Blog · 5 upvotes · 0 comments - [How Firecracker microVMs work under the hood to sandbox untrusted code and AI agents](https://daily.dev/posts/how-firecracker-microvms-work-under-the-hood-to-sandbox-untrusted-code-and-ai-agents-8jbiginnr) · Sylvain Kerkour · 1 upvotes · 0 comments --- Tags: [#vercel](https://daily.dev/tags/vercel), [#multi-tenancy](https://daily.dev/tags/multi-tenancy), [#build-systems](https://daily.dev/tags/build-systems) [View this post on daily.dev](https://daily.dev/posts/how-vercel-cut-build-wait-times-from-90-seconds-to-5-qbgsmgld2)