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Blacksmith logo

Blacksmith

Run GitHub Actions on faster bare-metal runners with lower Ubuntu per-minute pricing

api-usage-basedupdated Aug 16, 2026

Blacksmith is a drop-in replacement for GitHub-hosted runners that executes Actions on bare-metal gaming CPUs and source-shaped cache infrastructure. Migration requires a one-line YAML change. Features include colocated warm caches, persistent Docker layer caching on NVMe, CI observability with log search, and Firecracker microVM isolation. SOC 2 Type 2 certified, with Ubuntu x64 pricing at $0.004/min and 3,000 free minutes/month.

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Blacksmith was founded by ex-CockroachDB and Faire engineers who experienced firsthand how CI costs can reach millions at scale while still delivering slow builds. The core insight is that GitHub Actions runners use decade-old server CPUs optimized for throughput, not the single-core performance that compilation, testing, and Node.js actually need. Blacksmith replaces these with modern gaming-grade CPUs, co-located warm cache artifacts, and persistent NVMe storage for Docker layers. The company frames the savings as a combination of roughly 2x faster runtimes, 33% lower per-minute Ubuntu x64 pricing than GitHub, and up to 67% total savings for that baseline configuration.

The platform adds CI observability that GitHub lacks. Engineers spot misconfigurations and performance regressions through pipeline analytics, run global searches across CI logs, and see failed test logs posted as GitHub comments. Docker layer caching persists across runs so unchanged layers are reused rather than rebuilt, cutting Docker build times from minutes to seconds. Container caching pre-hydrates service containers on runners, removing repeated image pulls from job startup. All runs in Firecracker microVMs providing strong isolation, with SOC 2 Type II certification for enterprise security.

Blacksmith has raised $17.6M including a $10M Series A led by Google Ventures, and is part of Y Combinator W24. The company now reports 3,000+ organizations, 30K+ developers, and 50M+ jobs processed monthly, with customers including Supabase, Ashby, VEED, Chroma, and Clerk. Pricing starts at $0.004 per minute for Ubuntu x64 runners with 3,000 free minutes monthly; Ubuntu ARM and Windows runners have different public rates. Enterprise plans add 99.9% SLA, white-glove onboarding, and 24/7 support. The team supports open-source projects including Celery, Ladybird, Zen, and Limbo with free CI resources.

Pricing

Ubuntu x64 $0.004/min; Ubuntu ARM $0.0025/min; Windows x64 $0.008/min; 3,000 free min/mo; Enterprise custom

Platforms

GitHub Actions drop-in; Linux, Windows, macOS; x64/ARM; Docker caching, Firecracker VMs

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Use Cases

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Comparisons

Depot vs Blacksmith: Docker Build Runners or Bare-Metal CI Speed?

Depot is the stronger fit when CI time is dominated by Docker BuildKit, multi-architecture images, and shared build cache economics. Blacksmith is the stronger fit when a GitHub Actions team mainly wants faster general-purpose runners, test execution, and cache locality without redesigning the pipeline around container builds.

DepotBlacksmith

Blacksmith vs Woodpecker CI: CI/CD Platforms Compared

Blacksmith and Woodpecker CI both help teams run continuous integration pipelines, but with very different approaches. Blacksmith provides high-performance bare-metal runners for GitHub Actions at half the cost, while Woodpecker CI is a fully self-hosted CI/CD server inspired by Drone. The choice depends on whether you want to optimize existing GitHub Actions or run a completely independent CI system.

BlacksmithWoodpecker CI

FAQ

What is Blacksmith?

Blacksmith is a drop-in replacement for GitHub-hosted runners that executes Actions on bare-metal gaming CPUs and source-shaped cache infrastructure. Migration requires a one-line YAML change. Features include colocated warm caches, persistent Docker layer caching on NVMe, CI observability with log search, and Firecracker microVM isolation. SOC 2 Type 2 certified, with Ubuntu x64 pricing at $0.004/min and 3,000 free minutes/month.

Is Blacksmith free?

Blacksmith uses usage-based API pricing. Ubuntu x64 $0.004/min; Ubuntu ARM $0.0025/min; Windows x64 $0.008/min; 3,000 free min/mo; Enterprise custom

What are the best Blacksmith alternatives?

The top editor-verified Blacksmith alternatives are Woodpecker CI, Aviator, Atlantis, and more.

How does Blacksmith score in our review?

Our hands-on review scores Blacksmith 89/100 overall, based on speed, privacy, and developer-experience testing.