WarpBuild vs Ubicloud
WarpBuild does one thing: it runs your GitHub Actions jobs on fresh VMs for Linux, Windows and macOS, in its cloud or yours. Ubicloud is a whole open source cloud, with plain Linux VMs, Postgres, Kubernetes and GPUs, that also sells cheap GitHub Actions runners.
The companies and products
WarpBuild
WarpBuild sells hosted GitHub Actions runners: you change the runs-on label and your CI jobs run on its machines.
WarpBuild is a CI service, not an agent sandbox. Each GitHub Actions job runs in its own VM on Linux (x86-64 or arm64), Windows or macOS on Apple M4 Pro, and the VM and its disk are destroyed after the build. It also sells remote Docker builders, can run the same runners inside your own AWS, GCP or Azure account, and can host Claude Managed Agents sessions on its stock runners.
Ubicloud
Ubicloud is an open source cloud that runs VMs, managed Postgres, Kubernetes and GitHub Actions runners on leased bare-metal servers.
You rent Linux VMs (Standard with dedicated CPU, or cheaper Burstable with shared CPU) from Ubicloud's managed service, or run the same AGPL code on your own servers. Around the VMs it offers private subnets, an inbound firewall, load balancers, managed PostgreSQL, Kubernetes, GPU VMs, inference endpoints and cheap GitHub Actions runners. It is general infrastructure, not an agent sandbox, so this page compares the two where they overlap: giving an agent its own Linux machine.
Which use cases each one fits
For each use case, Battleships prices every sandbox provider on the same workload and sorts them from the cheapest monthly bill up. “94th cheapest of 377” means 93 of the other 376 providers run that workload, with every feature it needs, for less. “With limits” means the provider runs it but misses something, so it is listed after every full match. Open a use case for its whole ranking and what each provider misses.
| Use case and its workload | WarpBuild: price rank | Ubicloud: price rank | boat: price rank |
|---|---|---|---|
| Software factory 100 at once · 4 vCPU / 8 GB · 2,200 sessions of 8 h a month WarpBuild runners are wiped after every job; a Ubicloud VM keeps its files but starts as an empty OS, and boat comes with agents, snapshots and free stops. | 269th of 367, with limits $4,343 a month | 126th of 367, with limits $1,136 a month | 3rd cheapest of 367 $634 a month |
| Always-on AI employees 50 machines 24/7 · 2 vCPU / 4 GB An assistant that lives for weeks does not fit a WarpBuild job that GitHub stops after 5 days; a Ubicloud VM can run it if you build the agent setup yourself. | 285th of 366, with limits $5,650 a month | 154th of 366, with limits $1,139 a month | 5th cheapest of 366 $657 a month |
| Code interpreter bursts 100 at once · 1 vCPU / 2 GB · 200,000 sessions of 1 min a month | 287th of 345, with limits $600 a month | 59th of 345, with limits $52 a month | 186th of 345, with limits $2,000 a month |
| Sandboxes for your users 300 at once · 2 vCPU / 4 GB · 30,000 sessions of 23 min a month WarpBuild runners block all inbound traffic, and Ubicloud's default 256 vCPU quota needs a raise from support for 300 sandboxes; boat gives each sandbox HTTPS URLs. | 278th of 361, with limits $1,890 a month | 53rd of 361, with limits $390 a month | Cheapest of 361 $209 a month |
| RL rollouts 1,000 at once · 2 vCPU / 4 GB · 1,000,000 sessions of 3 min a month | 281st of 360, with limits $9,000 a month | 234th of 360, with limits $1,560 a month | 34th of 360, with limits $2,000 a month |
| Agent evals 250 at once · 4 vCPU / 8 GB · 15,000 sessions of 20 min a month | 294th of 364, with limits $1,440 a month | 31st cheapest of 364 $624 a month | 10th cheapest of 364 $200 a month |
| CI runners 40 at once · 8 vCPU / 16 GB · 6,000 sessions of 12 min a month Both sell managed GitHub Actions runners billed per minute; Ubicloud comes to $300 a month here against $864 on WarpBuild, and boat runs the runner on a general sandbox you set up yourself. | 94th cheapest of 377 $864 a month | 28th cheapest of 377 $300 a month | 4th cheapest of 377 $86 a month |
| 24/7 dev boxes 1 machine 24/7 · 4 vCPU / 8 GB A dev box needs a disk that stays: WarpBuild's disk goes away with the job, a Ubicloud VM keeps its disk but bills while stopped, and boat keeps the disk with free stops. | 182nd of 368, with limits $226 a month | 67th cheapest of 368 $91 a month | 18th cheapest of 368 $26 a month |
| Computer-use agents 50 at once · 4 vCPU / 8 GB · 20,000 sessions of 15 min a month Neither WarpBuild nor Ubicloud has a desktop or computer-use API; boat streams a 60fps desktop with Chromium on every machine. | 264th of 369, with limits $1,320 a month | 132nd of 369, with limits $312 a month | 6th cheapest of 369 $200 a month |
| Browser-use agents 50 at once · 2 vCPU / 4 GB · 30,000 sessions of 10 min a month | 280th of 367, with limits $720 a month | 188th of 367, with limits $156 a month | 7th cheapest of 367 $200 a month |
| Scraping & bots (startup scale) 50 at once · 1 vCPU / 2 GB · 100,000 sessions of 3 min a month | 306th of 346, with limits $878 a month | 165th of 346, with limits $78 a month | 6th cheapest of 346 $90 a month |
| Mass scraping & bots (undetectable) 1,000 at once · 1 vCPU / 2 GB · 3,000,000 sessions of 2 min a month | 275th of 338, with limits $17,550 a month | 60th of 338, with limits $1,573 a month | 71st of 338, with limits $1,800 a month |
| Parallel red teaming 200 at once · 2 vCPU / 4 GB · 5,000 sessions of 30 min a month | 264th of 360, with limits $435 a month | 129th of 360, with limits $81 a month | 2nd cheapest of 360 $200 a month |
| GPU eval jobs 10 at once · 8 vCPU / 32 GB · 500 sessions of 30 min a month Only Ubicloud fits: it rents Nvidia GPU VMs once support enables them, and neither WarpBuild nor boat has GPUs. | Can't run it | 93rd of 98, with limits $795 a month | Can't run it |
| macOS agents 5 at once · 4 vCPU / 8 GB · 1,000 sessions of 20 min a month Only WarpBuild fits: it has macOS runners on Apple M4 Pro, while Ubicloud and boat run Linux only. | 29th of 36, with limits $1,520 a month | Can't run it | Can't run it |
Key features
| Feature | WarpBuild | Ubicloud | boat |
|---|---|---|---|
| Kind of product | GitHub Actions runners and remote Docker builders, billed per minute | A general open source cloud: VMs, managed Postgres, Kubernetes, GPU VMs and GitHub Actions runners | A sandbox API for agents, on full VMs kept as long as you want |
| Isolation | Every job gets its own VM, created on demand and destroyed after the build | Every VM is a full KVM guest (Cloud Hypervisor) with its own kernel | Every sandbox is a full VM with its own kernel |
| GitHub Actions | Drop-in: change runs-on and jobs start on WarpBuild, with fast cache, Docker builders and unlimited concurrency on Linux and Windows | Managed x64 and arm64 runners, fully compatible with default runners, billed per minute of job time, with a $2.50 monthly credit | No managed runner service; you run the GitHub runner on a sandbox yourself |
| Operating systems and chips | Linux x86-64 and arm64, Windows Server 2022 and 2025, macOS on Apple M4 Pro | Linux VMs (Ubuntu, Debian, AlmaLinux); x64 and arm64 CI runners | Linux on x86-64 (AMD Ryzen 9 9950X hosts) |
| How long a machine lives | Until the job ends; GitHub stops a self-hosted runner job after 5 days | As long as you keep the VM; no session cap | No session cap on paid plans; stop and start it when you like |
| Files after a stop | The disk is destroyed after each build; cache and disk snapshots (deleted after 15 days) carry state over | The disk stays, but a stopped VM keeps billing as if it were running | The disk stays, with snapshots every minute and on stop; a stopped sandbox costs nothing |
| Copying a machine | No fork; a later runner can boot from a saved disk snapshot in 45 to 60 seconds | Stop the VM, capture a machine image (single disk up to 40 GiB), then boot new VMs from it | Fork a running sandbox in one call (disk, no memory) |
| Docker and nested virtualization | Docker on runners; /dev/kvm only on Linux x86-64, turned on with a label | Root over SSH, so Docker installs like on any Linux VM; nested virtualization is not documented | Docker, root, systemd and /dev/kvm on every machine |
| Reaching the machine | All inbound traffic blocked; SSH into failed jobs for debugging | Free public IPv6, public IPv4 for $3 a month; the VM runs TLS itself for HTTPS | HTTPS URLs for up to 50 ports, token-protected; raw TCP; SSH |
| Desktop and computer use | None; runners have no desktop stream | None; you install a desktop and browser on the VM yourself | 60fps desktop and Chromium, computer use and browser control, embeddable stream |
| Coding agents | Runs Claude Managed Agents sessions on stock Linux and macOS runners, driven through Anthropic's API | None; you install and drive agents yourself, for example over SSH | Claude Code, Codex, OpenCode and more preinstalled, with a prompt, steer and events API |
| Keeping keys out of the machine | GitHub secrets are passed into the runner environment | No credentials proxy; secrets live on the VM | AI credentials proxy for model providers and any HTTPS API you register; real keys never enter the sandbox |
| GPUs and self-hosting | No GPUs; BYOC runs the runners inside your own AWS, GCP or Azure account | Nvidia GPU VMs on request, and the whole stack is AGPL code you can run on your own servers | No GPUs, managed service only |
| Where it runs | WarpBuild's cloud (EU region on the enterprise tier), or BYOC in your own cloud account | Germany, Finland and Virginia (US), plus GPUs in Istanbul | EU only: Germany, Finland, France |
Every feature Battleships tracks (43)
| Feature | WarpBuild | Ubicloud | boat |
|---|---|---|---|
| Full VM (own kernel) | Yes | Yes | Yes |
| Docker inside | Yes | Yes | Yes |
| Nested virtualization | Yes | Not published | Yes |
| Root | Yes | Yes | Yes |
| Systemd | Not published | Not published | Yes |
| Desktop GUI | No | No | Yes |
| Browser | No | No | Yes |
| Computer-use API | No | No | Yes |
| SSH | Yes | Yes | Yes |
| Persistent disk | No | Yes | Yes |
| Pause/resume | No | No | Yes |
| Automatic snapshots | No | No | Yes |
| Fork/clone | No | Yes | Yes |
| Live fork (no pause) | No | No | Yes |
| Memory fork | No | No | No |
| Custom image (Docker or snapshot) | Yes | Yes | Yes |
| ≥24 h sessions | Yes | Yes | Yes |
| Idle auto-stop | Yes | No | No |
| Wake on request | Yes | No | No |
| HTTPS preview URLs | No | No | Yes |
| Raw TCP inbound | No | Not published | Yes |
| Public IPv4 | No | Yes | No |
| Egress allowlist | Yes | No | No |
| Secret proxy | No | No | Yes |
| Secret proxy for any API | No | No | Yes |
| Preinstalled agents | Yes | No | Yes |
| Agent harness API | No | No | Yes |
| MCP server | Yes | No | No |
| GPU | No | Yes | No |
| Windows | Yes | No | No |
| Arm64 | Yes | Yes | No |
| Self-hosting | No | Yes | No |
| BYOC | Yes | Yes | No |
| Open source | No | Yes | No |
| Scoped API keys | Yes | Not published | Yes |
| Spend limits | Not published | Not published | Yes |
| Usage per sandbox (API) | Yes | No | Yes |
| Audit logs | Not published | Yes | No |
| SSO | Yes | Yes | No |
| SOC 2 | Yes | Yes | No |
| HIPAA | No | No | No |
| EU data residency | Yes | Yes | Yes |
| Zero data retention | Not published | Not published | Yes |
Performance
There is no comparable measurement for WarpBuild or Ubicloud: neither was part of the public StarSling benchmark, where boat did 26.69 Node.js build-and-test runs per second at 4 vCPU / 8 GB on dedicated AMD Ryzen 9 9950X hosts. WarpBuild's own speed claims compare its runners with GitHub's, and Ubicloud results would depend on the family you pick, since Burstable VMs get half of each vCPU.
Node.js build-and-test loop at 4 vCPU / 8 GB, higher is better. Measured with the open hpc-sandbox-benchmarks suite. WarpBuild and Ubicloud have no published run in this suite yet, so there is no like-for-like number to compare.
Pricing in five scenarios
Each bill is priced from the providers' public price lists by the open Battleships engine, with the cheapest plan that runs the scenario.
| Scenario | WarpBuild, a month | Ubicloud, a month | boat, a month |
|---|---|---|---|
| One coding agent, workdays 4 vCPU / 8 GB, 50 GB disk, 8 hours a day, 22 days a month, files kept between days | $57 · Pay as you go · with limits | $22 · Usage | $20 · $20/mo |
| One agent that never stops 4 vCPU / 8 GB, 50 GB disk, running 24/7 all month | $237 · Pay as you go · with limits | $91 · Usage | $26 · $20/mo |
| 50 agents in parallel 50 machines of 4 vCPU / 8 GB at once, 8-hour sessions, 1,100 sessions a month, Docker inside | $2,851 · Pay as you go · with limits | $1,098 · Usage | $317 · $20/mo × 3 seats |
| Sandboxes for your users 2 vCPU / 4 GB, 30,000 sessions of 10 minutes a month, up to 300 at once | $810 · Pay as you go · with limits | $156 · Usage | $200 · $100/mo × 2 seats |
| 1,000 short jobs at once 2 vCPU / 4 GB, 1,000 at once, 3 minutes each, 200,000 jobs a month | $1,800 · Pay as you go · with limits | $312 · Usage · with limits | $2,000 · $2000/mo · with limits |
WarpBuild: WarpBuild bills runners per minute while a job runs, with no plan fee, from $0.003 a minute for 2 vCPU on arm64; Windows costs twice the Linux x86-64 rate and macOS $0.08 a minute. Cache, snapshot storage and restores are extra, and BYOC runners cost $0.002 a minute on top of your own cloud bill.
Ubicloud: Ubicloud bills runners per minute of job time, with a $2.50 monthly credit for runner time, and bills VMs per minute for as long as they exist, running or stopped. A public IPv4 adds $3 a month, and Germany and Finland prices rose 25% on September 1, 2026.
Ubicloud: You pick a monthly plan from $20, and all of it becomes usage credit spent per second on running sandboxes. A stopped sandbox costs nothing and keeps its disk.
Limits in those scenarios
None of the five agent scenarios fits WarpBuild as it is sold, because a runner exists only while a GitHub Actions job runs, keeps no disk and hits GitHub's 5 day cap. Ubicloud fits four of them as plain VMs, but a project starts at 256 vCPU once verified, so 300 user sandboxes and 1,000 jobs at once need a raise, and the cheap burstable shape gets throttled above half of each vCPU. On boat, the 1,000-job burst is limited by starts per minute and per day, so it gets queued even on the $2,000 plan.
| Scenario | WarpBuild | Ubicloud | boat |
|---|---|---|---|
| One coding agent, workdays |
| None that bite | None that bite |
| One agent that never stops |
| None that bite | None that bite |
| 50 agents in parallel |
| None that bite | None that bite |
| Sandboxes for your users |
| None that bite | None that bite |
| 1,000 short jobs at once |
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Which one should you use?
Use WarpBuild when
you want faster GitHub Actions CI with one label changed, especially on macOS or Windows, or inside your own AWS, GCP or Azure account.
- macOS and Windows runners. Useful if you build iPhone, Mac or Windows apps: WarpBuild runs macOS on Apple M4 Pro and Windows Server, and Ubicloud does not.
- CI tuned for speed. Useful if CI is your bottleneck: WarpBuild adds fast cache, remote Docker builders and disk snapshot runners on top of drop-in runners.
- Runners in your own cloud. Useful if CI must run in your own AWS, GCP or Azure account, with your security groups and static egress IPs.
Use Ubicloud when
you want cheap Linux CI runners next to plain VMs, Postgres, Kubernetes or GPUs, a US region, or an open source cloud you can run yourself.
- Lower CI bills. Useful if you mostly run Linux jobs: Ubicloud's x64 and arm64 runners came to about a third of WarpBuild's price in our CI scenario.
- A whole cloud, not only CI. Useful if you also need long-lived VMs, managed Postgres, Kubernetes or Nvidia GPU VMs next to your runners.
- Open source you can run yourself. Useful if you want to own the stack: Ubicloud's code is AGPL and runs on leased bare-metal servers you control.
Where boat fits
If what you are really running is AI agents, not CI jobs, neither WarpBuild nor Ubicloud gives you an agent sandbox: WarpBuild machines live for one job, and a Ubicloud VM is an empty Linux box you set up yourself. boat gives each agent a full VM that keeps its work, serves what it builds and comes with coding agents you drive from outside.
A machine that keeps its work and stops for free
A WarpBuild runner's disk is destroyed when the job ends, so agents lose their clone and installs. A Ubicloud VM keeps its disk but bills while stopped. boat snapshots every minute, stops for free and forks a running sandbox.
Apps and a desktop people can open
WarpBuild blocks all inbound traffic, and on Ubicloud you run TLS and install a desktop yourself. boat gives each sandbox HTTPS URLs on up to 50 ports, raw TCP and a 60fps desktop with Chromium for computer use.
Coding agents and keys handled for you
On both, secrets sit inside the machine where agent-written code can read them, and WarpBuild only hosts Claude Managed Agents. boat preinstalls Claude Code, Codex and OpenCode with an API to drive them, and its credentials proxy keeps real keys out.
Use boat when the work is AI agents: each one gets a full VM that keeps its files, serves the apps it builds, shows a desktop and runs coding agents you drive from outside. Compare it one to one: boat vs WarpBuild and boat vs Ubicloud.
Questions people ask
Is WarpBuild cheaper than Ubicloud?
Not in our CI runner scenario: it comes to $864 a month on WarpBuild and $300 on Ubicloud. WarpBuild's extras, like macOS, Windows, snapshot runners and BYOC, are what you pay more for. boat comes to $86 there, but you run the GitHub runner yourself.
Which is faster, WarpBuild or Ubicloud?
There is no comparable public measurement of either. WarpBuild compares its runners with GitHub's own, and Ubicloud's speed depends on whether you pick a Standard VM with dedicated CPU or a Burstable one. boat measured 26.69 runs per second in the StarSling benchmark at 4 vCPU / 8 GB.
Can WarpBuild or Ubicloud run Docker?
Yes. WarpBuild runners ship with Docker and can turn on /dev/kvm on Linux x86-64 with a label. Ubicloud's CI runners include Docker, and on a VM you have root to install it. boat has Docker, root, systemd and /dev/kvm on every machine.
Does Ubicloud have macOS or Windows runners like WarpBuild?
No. Ubicloud runs Linux only, with x64 and arm64 runners. WarpBuild has macOS on Apple M4 Pro and Windows Server 2022 and 2025. boat also runs Linux only.
Can I use WarpBuild or Ubicloud as a sandbox for AI agents?
Only partly. A WarpBuild runner lives for one job and loses its disk, though it can host Claude Managed Agents sessions. A Ubicloud VM keeps its disk, but you install the agents, the desktop and the HTTPS setup yourself, and it bills while stopped. boat is built for agents, with all of that included.
Where do WarpBuild and Ubicloud run?
WarpBuild runs in its own cloud, with an EU region on its enterprise tier, or inside your own AWS, GCP or Azure account. Ubicloud runs in Germany, Finland and Virginia, with GPUs in Istanbul, or on your own servers. boat runs only in the EU (Germany, Finland and France).
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