Buildkite vs Blacksmith
Blacksmith makes GitHub Actions faster and cheaper to run. Buildkite is built for when GitHub Actions itself is the limit.
Blacksmith is very good at one thing: running GitHub Actions jobs on faster hardware for less per minute. Change one line in runs-on and your workflows run on its bare-metal fleet. If runner speed and cost are the problem, it is aimed directly at them.
Buildkite is a different purchase. It is a CI platform you design: agents on your own infrastructure or ours, any OS and any chip, pipeline steps generated at runtime, and test intelligence and registries in the same system. A runner is a layer; Buildkite is the stack.
Buildkite supports GitHub, GitLab, Bitbucket, Origin, Entire, Pierre Computer Co’s code.storage, or your own Git server. Origin and Entire run CI on Buildkite, and Pierre Computer Co built code.storage on Buildkite CI.
- Choose Buildkite: when the GitHub Actions model, not the runner, has become the limit, and you want a platform you control.
- Choose Blacksmith: when GitHub Actions still fits and you want it faster and cheaper with a one-line change.
The short version
What Buildkite is built for
- Run on your infrastructure, Buildkite’s, or both
- Generate pipeline steps at runtime, not ahead of time
- Build from any Git host, not only GitHub
- Keep test intelligence and registries in the same system
- Start free, with dynamic pipelines and test splitting included
What Blacksmith is good at
- A one-line
runs-onchange, with workflows kept as they are - Bare-metal gaming CPUs with co-located caching
- Per-minute prices below GitHub’s hosted runners
- Test and CI analytics, Slack monitors and SSH into running jobs
- No concurrency limits, by its own documentation
Feature comparison
By capability, not bias. Where Blacksmith is the better choice, we say so.
| Capability | Buildkite | Blacksmith |
|---|---|---|
| What it is | A CI platform: orchestration, test intelligence, registries and governance in one system. | Runners for GitHub Actions. Workflows stay on GitHub Actions; the compute underneath changes. |
| Adoption | A migration, made incremental. The GitHub Actions compatibility plugin (public preview) runs existing workflows as Buildkite jobs, and the pipeline converter drafts native pipelines. | Install the GitHub App and change runs-on, for example to blacksmith-2vcpu-ubuntu-2404. |
| Pipeline model | Steps generated at runtime in Go, Python or Bash, so the build adapts to the commit. Static YAML works too. | GitHub Actions YAML: matrices and reusable workflows, written ahead of time. |
| Where builds run | Self-hosted agents on your infrastructure, on-prem or any cloud, or Buildkite-hosted Linux and Mac M4 agents, with Windows in private preview. Mix both in one pipeline using separate queues. | Firecracker microVMs on Blacksmith’s own bare metal, in US and EU data centres. |
| Architectures and OS | Linux, macOS, Windows, Arm and GPU on your own hardware, plus hosted Linux and Mac M4. | Ubuntu x64 and Arm, macOS M4, and Windows in public beta. |
| Scale and concurrency | Free: 10 concurrent jobs · Pro: up to 250 concurrent agents · Enterprise: unlimited self-hosted agents. Multiple enterprise customers run more than 100,000 concurrent agents. | Blacksmith’s documentation says it “does not impose any concurrency limits”. |
| Source control | GitHub, GitLab, Bitbucket, Origin, Entire, code.storage, or your own Git server. | GitHub: github.com, GitHub Enterprise Server and GitHub Enterprise Cloud with data residency, for organisations rather than personal accounts. |
| Test intelligence | Splitting by timing on every plan, flaky detection, and ownership mapped to teams through a TESTOWNERS file. Test state management with auto-quarantine on Pro and Enterprise. | Test analytics parsed automatically from JUnit XML or logs, with failing tests flagged on pull requests. Testboxes in early beta. |
| Observability | OpenTelemetry traces from agents and the platform to the collector you already run, configured once per cluster for hosted and self-hosted agents. In preview. | Logs, per-job metrics, CI analytics and Slack monitors in Blacksmith’s dashboard. |
| Governance and security | SOC 2 Type II on every plan. SSO and signed pipelines from Pro; SCIM, custom SAML, audit log exports and private log storage on Enterprise. | SOC 2 Type 2 and GDPR, on hardware in ISO 27001 data centres. Sign-in is delegated to GitHub. |
| Reliability commitment | 99.95% platform and 99.5% hosted-agent uptime on Enterprise, in a published SLA. | 99.9% SLA on Enterprise. |
| Pricing model | Free: $0 · Pro: $30 per active user/month, 10 self-hosted agents included, $3.50 per agent/month after · Enterprise: custom. Your own compute isn’t billed; hosted Linux from $0.004 per vCPU-minute (pricing). | Per minute, 2 vCPU: Ubuntu x64 $0.004, Arm $0.0025, Windows $0.008; macOS M4 $0.08. 3,000 free minutes a month. No per-seat fee. |
Your GitHub Actions workflows already run on Buildkite
Blacksmith keeps you on GitHub Actions. Moving to Buildkite is a real migration, but it doesn’t have to start with a rewrite. The GitHub Actions compatibility plugin, open source and in public preview, runs your existing workflow files as Buildkite jobs with minimal changes. Imported workflows run alongside native Buildkite steps, so you can move pipeline by pipeline instead of all at once. On the Free plan it costs nothing to find out whether your workflows fit.
Then move at your own pace:
- Start with a simple Linux x86-64 workflow, which is where the docs recommend you begin.
- Let the pipeline converter draft a native pipeline. It’s LLM-assisted, and a starting point rather than a complete automated migration.
- Replace imported jobs with native steps over time, as dynamic pipelines start to earn their keep.
It’s a preview and the boundaries are real. Check the compatibility matrix against your workflows rather than assuming a fit — and if you’d rather not do that alone, we’ll validate one with you.
Where the difference actually shows up
Blacksmith optimises the runner. Buildkite optimises the system around it. Both are legitimate; they answer different questions.
- The bottleneck stops being the CPU. Faster hardware shortens every job, but it doesn’t change which jobs run. When every commit rebuilds everything, the limit is the pipeline model. Buildkite generates steps at runtime, so a monorepo builds what changed instead of accumulating workflow files and path filters.
- The work has to run somewhere specific. Blacksmith runs on its own bare metal in the US and EU. On Buildkite, an agent is a binary: it runs in your cloud account, on your Macs and GPU boxes, inside your network, connecting outbound only.
- The code isn’t only on GitHub. Blacksmith works with GitHub organisations. Buildkite works with any Git host, so CI is never the reason you can’t change source control.
Buildkite asks for deliberate setup up front, and gives you a system you extend rather than replace when the work changes shape.
Built to fit your environment
Figures below combine Buildkite’s own capacity benchmarks with results from customer case studies.
concurrent agents across enterprise customers
Elastic cut Kibana pull request CI by 70%; Shopify cut build times by 75%
lower p90 mobile build times at Reddit (33% at p50), with queue times around five seconds
Cost breakdown
Blacksmith meters runner minutes. Buildkite prices the platform per active user, with compute on top, and doesn’t bill compute you run yourself.
Free:
- Up to 5 users, 10 concurrent jobs
- 2,000 Linux vCPU-minutes and 250k test executions per month
- 50GB artifact storage, 250GB downloads, 30-day retention
- Dynamic pipelines and test splitting included
- Community support
Pro:
- $30 per active user per month, up to 50 users
- Up to 250 concurrent agents, 10 included, $3.50 per agent/month after
- 4,000 Linux vCPU-minutes included, plus M4 Mac agents and larger machine sizes
- 1M test executions per month, then $15 per additional million
- Test state management and auto-quarantine
- SSO and signed pipelines
- Priority email support
Enterprise:
- Unlimited users on a 30-user minimum
- Unlimited self-hosted agents, custom limits and retention
- 99.95% uptime commitment
- Enterprise support
Hosted agents: Linux $0.004 per vCPU-minute (a 2 vCPU Small agent is $0.008 a minute) and Mac M4 $0.02 per vCPU-minute, metered to the second.
Every plan starts with a 30-day all-access trial. No credit card needed. View pricing →
Blacksmith prices the minute and meters the extras:
- 2 vCPU runners at $0.004 a minute for Ubuntu x64, $0.0025 for Arm and $0.008 for Windows; macOS M4 at $0.08
- 3,000 free minutes a month per organisation, counted in x64 2 vCPU minutes and shared across runner types
- Docker layer caching and sticky disks at $0.50 per GB per month; static IPs at $100 per IP per month
- No per-seat fee. Enterprise adds a 99.9% SLA and dedicated support
On per-minute price for GitHub Actions workloads, Blacksmith is hard to beat, and it costs less per hosted minute than Buildkite’s hosted agents too. Buildkite’s case is different: per-user and per-agent pricing, and compute on your own infrastructure that we don’t meter.
Buildkite plan figures read from buildkite.com/pricing on 22 October 2026. Blacksmith prices as published by Blacksmith the same day.
Where your builds run
Buildkite makes flexible, persistent execution the default, and keeps the sensitive parts on your side of the line.
- Buildkite: self-hosted agents make outbound HTTPS connections only, with no inbound ports to open, and source code and secrets stay in your environment. Keep agents warm between runs with a local git mirror, or make them ephemeral. Your call, per queue. Or use Buildkite-hosted agents.
- Blacksmith: each job runs in a fresh Firecracker microVM on Blacksmith’s own bare metal, in US and EU data centres, destroyed when the job ends. Sticky disks carry selected caches between runs.
The real difference isn’t speed, it’s control. On Buildkite, you own the machines, the images and the network, and can tune all of it. The open-source agent runs anywhere a binary can.
Who answers when something breaks (and what customers say about it)
When delivery is strategic, support matters as much as features. Buildkite gives you direct access to the people who built it, not a tiered helpdesk. G2 and PeerSpot customers called it fast, responsive, and knowledgeable.
4.7 / 5 31 reviews · 22 October 2026
G2 rating, where reviewers cite responsive, knowledgeable support
The honest trade-off
If GitHub Actions fits and the pain is runner speed or cost, Blacksmith is the smaller change.
- One line to change, no migration, and faster, cheaper runs by Blacksmith’s own measure.
- You keep every workflow, every action, and the GitHub interface your team already knows.
Come to Buildkite when the limit is GitHub Actions itself: when the pipeline needs to be generated rather than written, when builds have to run on your own infrastructure, when source control goes beyond GitHub, or when access control has to answer to an auditor.
Choose Blacksmith if…
- GitHub Actions does what you need, and you want it faster and cheaper.
- A migration isn’t on the table.
- You’re staying on GitHub, and the workflow model still fits.
- Your pain is runner speed and cost, not the platform.
- You’re comfortable with builds running on a vendor’s managed hardware.
It depends on your situation
The decision usually comes down to four things.
| Capability | Lean Buildkite | Lean Blacksmith |
|---|---|---|
| Your actual problem | The GitHub Actions model, scale or control. You’ve hit the platform, not the CPU. | Runner speed and cost. GitHub Actions otherwise fits. |
| Effort you’ll spend | A migration, made incremental, for a platform you control. | One line, done today. |
| Where your code runs | Any infrastructure, on-prem or any cloud, agent outbound-only, or Buildkite-hosted. Your choice, on any plan. | Blacksmith’s bare-metal fleet in the US and EU. |
| Source control | Any Git host, including your own Git server. | GitHub, and you’re staying there. |
Frequently asked questions
Got a question that’s not on our list? Want a demo? Just want to chat? Get in touch.
Is Buildkite a Blacksmith alternative?
Partly. Both run CI jobs, but Blacksmith’s centre of gravity is the runner: GitHub Actions on faster, cheaper hardware. Buildkite is the platform around the jobs — orchestration, test intelligence, registries and governance — on compute you choose.
Is Blacksmith faster than Buildkite?
Blacksmith competes on raw runner speed, with bare-metal gaming CPUs it says are 2x faster than GitHub’s runners. Buildkite competes on a different axis: build only what changed, fan out as wide as your infrastructure allows, and keep agents warm between runs. We don’t publish a runner-for-runner benchmark. The only comparison worth acting on is your workload, on comparable hardware, with the same cache strategy.
Do I have to leave GitHub Actions to use Buildkite?
Not on day one. The compatibility plugin, in public preview, runs your existing workflows as Buildkite jobs. Builds then run on Buildkite agents, and you convert to native pipelines when you’re ready.
Can we use Buildkite if we’re not on GitHub?
Yes. Buildkite runs against GitHub, GitLab, Bitbucket, Origin, Entire, Pierre Computer Co’s code.storage, or your own Git server. Blacksmith works with GitHub organisations, including GitHub Enterprise Server.
Where does my code run?
With Blacksmith, in Firecracker microVMs on its own bare metal in US and EU data centres. With Buildkite, wherever you choose on any plan: self-hosted agents connect outbound-only and keep source and secrets in your environment, or use Buildkite-hosted agents.
Can I send CI traces to my own observability stack?
On Buildkite, yes. Send OpenTelemetry traces from agents and the platform to any OTLP collector, and configure the exporter once per cluster for hosted and self-hosted agents. It’s in preview. Blacksmith’s logs, metrics and analytics live in its own dashboard.
We’re a small team on GitHub Actions. Where should we start?
Where the pain is. If it’s runner speed or cost and nothing else, changing runners is the smaller step. If it’s the model — rebuilding everything on every commit, or needing builds on your own machines — run one real workflow through the compatibility plugin on the Free plan and decide from evidence rather than from a comparison page.
Related resources
See it on your pipelines
Bring a repo and a real workload. We’ll run one of your existing GitHub Actions workflows on Buildkite and show you what the platform does around it. If faster runners are all you actually need, we’ll tell you that too.
