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Blazing fast builds, out of the box

CarbonRunner runs on the latest AMD EPYC CPUs with NVMe SSDs and smart caching, giving your GitHub Actions unmatched speed from the very first job.

Linux Build Benchmark: CarbonRunner 2vCPU vs GitHub 2vCPU

We benchmarked Linux builds to compare CarbonRunner against GitHub's 2vCPU runners. On identical hardware, CarbonRunner completed the build in 27 minutes for $0.17, while GitHub took 37 minutes at a cost of $0.30 — making CarbonRunner 27% faster and 43% cheaper.

Scaling up to CarbonRunner's super-fast 4vCPU runner, the build finished in just 17 minutes for $0.21. That's 54% quicker and 30% cheaper than GitHub's 2vCPU runner, proving that CarbonRunner delivers faster builds with lower costs.

linux

17 mins
$0.21 USD
CarbonRunner 4vcpu
26 mins
$0.16 USD
CarbonRunner 2vcpu
37 mins
$0.30 USD
Github 2vcpu

These are updated weekly on Monday mornings (UTC time)


Optimized Infrastructure for Faster Builds

CarbonRunner is built on the latest AMD EPYC CPUs with high core density, perfectly tuned for parallel workloads. Paired with super-fast NVMe SSDs, you get ultra-low latency disk access for build caching and Docker layers.

On top of that, our in-built caching for Go, Node, and Docker comes pre-configured out of the box — shaving valuable minutes off every job.

We've got the latest latest AMD EPYC CPUs - high core density, optimized for parallel workloads.
Parallel Workload Optimized
Super fast NVMe SSDs - low-latency disk access for build caching and Docker layers.
Low-Latency Disk Performance
In-built caching - pre-configured for Go, Node, and Docker, saving minutes every job.
Minutes Saved on Every Job

Time To Start

The time between Github creating a workflow job run and it being spun up on a runnner. We keep a pool of Github runners ready to go in low carbon regions, sometimes though, if you request an uncommon configuration such as (arm64,ubuntu-latest,kvm) we might not have one on hand and we'll start one up on the fly. This incurs a time cost of around 45s-90s.

We're happy with a P50 of 8s. We think this is fair based upon:

  1. 1. The time it takes Github to generate and send us a webhook 25s (see below)
  2. 2. A VM Instance picking up the job (<2s) and generating a Github JitConfig (~700ms)
  3. 3. The Github runner contacting Github and saying it's started the job ~2s
  4. 4. Regional latency. EU servers typically see a 80ms-170ms
P50 (Median)
5s
50% of jobs start in less this time
P90
18s
90% of jobs start in less this time
P95
220s
95% of jobs start in less this time

Github Webhook Delay

We try to ingest webhooks as quickly as possible in a highly reliable way.

P50 (Median)
2s
50% of jobs are received in less than this time
P90
2s
90% of jobs are received in less than this time
P95
82s
95% of jobs are received in less than this time

Cut Enterprise Cloud Costs by 25%

CarbonRunner is designed to be 25% cheaper than GitHub Actions on every compute minute — no matter the CPU size. By intelligently routing workloads across AWS, Azure, and GCP, we avoid overpriced regions and capacity bottlenecks.