Freestyle vs Koyeb
Freestyle gives each agent a full Linux VM with systemd, Docker and nested virtualization that can pause with its memory and fork while it runs. Koyeb runs sandboxes as serverless microVMs from any Docker image, with GPUs, scale to zero and regions in the EU, US and Asia.
The companies and products
Freestyle
Freestyle sells full Linux virtual machines for AI agents, built for long running, complex tasks.
Each Freestyle VM is a KVM virtual machine with its own kernel, booted from an Ubuntu base snapshot with systemd, Docker and coding agent CLIs preinstalled. VMs can be paused with their memory, snapshotted while running, forked and woken by the next request, and every VM starts behind a default-deny firewall. It is built for teams that give each agent or each user its own machine, driven from a TypeScript SDK, a CLI or an API.
Koyeb
Koyeb is a serverless cloud for apps, inference and sandboxes, and in February 2026 it agreed to join Mistral AI.
A Koyeb sandbox is a Koyeb service: a microVM started from any Docker image and driven from Python or JavaScript SDKs that run commands, read files and expose a port. It can scale to zero when idle and wake on the next request, and it can run on CPU or GPU instance types. It is built for teams that run AI agents or untrusted code next to apps they already host on Koyeb.
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. “40th cheapest of 345” means 39 of the other 344 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 | Freestyle: price rank | Koyeb: price rank | boat: price rank |
|---|---|---|---|
| Software factory 100 at once · 4 vCPU / 8 GB · 2,200 sessions of 8 h a month A software factory needs Docker, systemd and room to build; Freestyle has all three in a full VM, Koyeb does not document nested virtualization, and boat runs the same builds on faster CPUs. | 241st of 367, with limits $3,311 a month | 54th of 367, with limits $366 a month | 3rd cheapest of 367 $634 a month |
| Always-on AI employees 50 machines 24/7 · 2 vCPU / 4 GB | 263rd of 366, with limits $4,195 a month | 135th of 366, with limits $923 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 Both fit short code runs: Koyeb scales to zero after 5 idle minutes and wakes on the next request, and Freestyle pauses a VM with its memory and wakes it the same way. | 40th cheapest of 345 $482 a month | 4th cheapest of 345 $66 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 Both fit; Freestyle and Koyeb wake a sleeping sandbox on its next request, while boat gives each user a faster machine with a desktop and HTTPS on up to 50 ports. | 16th cheapest of 361 $1,358 a month | 6th cheapest of 361 $495 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 Freestyle can snapshot a running VM with its memory and boot copies from it; Koyeb's snapshots with running processes exist only in its SDK and are labelled experimental. | 107th of 360, with limits $6,600 a month | 237th of 360, with limits $1,631 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 | 53rd cheapest of 364 $1,046 a month | 19th cheapest of 364 $429 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 CI that builds Android apps or VM images needs /dev/kvm, which Freestyle and boat expose and Koyeb does not document. | 168th of 377, with limits $625 a month | 142nd of 377, with limits $88 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 its files to stay; Freestyle keeps the VM disk, Koyeb's local disk is lost on redeploy unless you add a volume, and boat keeps the disk while a stopped sandbox costs nothing. | 98th cheapest of 368 $151 a month | 217th of 368, with limits $37 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 Computer-use agents need a desktop; boat streams a 60fps Linux desktop, Freestyle has guides to install one yourself, and Koyeb sandboxes have none. | 234th of 369, with limits $940 a month | 81st of 369, with limits $123 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 | 257th of 367, with limits $482 a month | 172nd of 367, with limits $123 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 | 278th of 346, with limits $482 a month | 172nd of 346, with limits $89 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 | 183rd of 338, with limits $6,560 a month | 65th of 338, with limits $1,683 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 | 272nd of 360, with limits $482 a month | 233rd of 360, with limits $299 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 Koyeb runs GPU instances from RTX 4000 cards up to H100 and H200; Freestyle offers private GPU sandboxes only on Enterprise, and boat has no GPUs. | Can't run it | 3rd cheapest of 98 $628 a month | Can't run it |
| macOS agents 5 at once · 4 vCPU / 8 GB · 1,000 sessions of 20 min a month | Can't run it | Can't run it | Can't run it |
Key features
| Feature | Freestyle | Koyeb | boat |
|---|---|---|---|
| Isolation | Full KVM VM with its own kernel | MicroVM per instance | Full VM with its own kernel on dedicated AMD Ryzen 9 9950X hosts |
| CPU benchmark (4 vCPU / 8 GB) | 9.64 runs/s; Freestyle says it oversubscribes its CPUs | Not benchmarked; at least 0.25 dedicated vCPU per GB of memory, eco instances guarantee half of each vCPU | 26.69 runs/s |
| Root, systemd, Docker, nested virtualization | Yes; systemd is pid 1, Docker runs from boot, full KVM support | Starts from any Docker image; nested virtualization not documented | Yes, with /dev/kvm for Android emulators and VMs |
| Biggest machine | Up to 32 vCPU / 64 GiB on Pro, 64 / 128 with custom limits | Instance types up to 40 vCPU / 128 GB, and GPU types far larger | Up to 16 vCPU / 32 GB on the $100 plan and above |
| Disk that survives | VM disk is kept, and billed for its allocated size while running, paused or stopped | Local disk is lost on redeploy; volumes (preview, 1 to 10 GB, two regions) persist | Disk is kept across stops and saved every minute; a stopped sandbox costs nothing |
| Sleep and wake | Pause saves memory and disk; a VM paused by idle timeout resumes on the next request | Scales to zero after 5 idle minutes and wakes on the next request; Light Sleep wakes in about 200 ms | Stop and start by API; resume boots the machine again |
| Snapshots and fork | Clone a running VM without pausing it; snapshots capture memory and disk | SDK snapshots of the filesystem or running processes, then new sandboxes from them (experimental) | Fork a running sandbox with its disk |
| Desktop, browser and computer use | Guides to install GNOME or Xvfb, VNC and Chromium yourself | No desktop or browser in the sandbox SDK | Linux desktop streamed at 60fps, Chromium and computer use built in |
| Coding agents | claude, codex, opencode and openclaw preinstalled, driven through exec or a terminal | Tutorials that run agents through the command API; an MCP server lets agents manage Koyeb | Seven agents preinstalled, with a prompt, steer and events API |
| Keeping API keys out of the sandbox | Credentials injected at the edge for HTTPS headers, Postgres and S3; the VM must trust the Freestyle CA | Secrets are set as environment variables inside the service | Credentials proxy for model providers and any HTTPS API; switch a credential to another account when credits run out |
| Inbound access | HTTPS on free style.dev names or your own domain, forward auth, other public protocols; no dedicated IPv4 | One exposed HTTPS port at a time, plus an optional TCP proxy to one port; no dedicated IP | HTTPS URLs for up to 50 ports, token-protected by default; raw TCP; dedicated IPv4 or IPv6 |
| Outbound rules | Default-deny firewall with allow rules by IP, VM, VPC or exact domain | Block all outbound traffic, or allow only listed IPs and CIDRs | Open internet, no provider-side allowlist |
| GPUs | Private GPU sandboxes on Enterprise only | RTX 4000 SFF Ada up to H100, H200 and multi-GPU | No |
| Regions | Not listed; the docs name a San Jose, US data center | EU, US and Asia | EU only (Germany, Finland, France), zero data retention |
Every feature Battleships tracks (43)
| Feature | Freestyle | Koyeb | boat |
|---|---|---|---|
| Full VM (own kernel) | Yes | Yes | Yes |
| Docker inside | Yes | Yes | Yes |
| Nested virtualization | Yes | No | Yes |
| Root | Yes | Not published | Yes |
| Systemd | Yes | Not published | Yes |
| Desktop GUI | No | No | Yes |
| Browser | No | No | Yes |
| Computer-use API | No | No | Yes |
| SSH | Yes | No | Yes |
| Persistent disk | Yes | Yes | Yes |
| Pause/resume | Yes | Yes | Yes |
| Automatic snapshots | Yes | Yes | Yes |
| Fork/clone | Yes | Yes | Yes |
| Live fork (no pause) | Yes | Not published | Yes |
| Memory fork | Yes | Yes | No |
| Custom image (Docker or snapshot) | Yes | Yes | Yes |
| ≥24 h sessions | Yes | Yes | Yes |
| Idle auto-stop | Yes | Yes | No |
| Wake on request | Yes | Yes | No |
| HTTPS preview URLs | Yes | Yes | Yes |
| Raw TCP inbound | Yes | Yes | Yes |
| Public IPv4 | No | No | No |
| Egress allowlist | Yes | Yes | No |
| Secret proxy | Yes | No | Yes |
| Secret proxy for any API | Yes | No | Yes |
| Preinstalled agents | Yes | Yes | Yes |
| Agent harness API | No | No | Yes |
| MCP server | No | Yes | No |
| GPU | Yes | Yes | No |
| Windows | No | No | No |
| Arm64 | No | No | No |
| Self-hosting | No | Yes | No |
| BYOC | No | Yes | No |
| Open source | No | No | No |
| Scoped API keys | Yes | Not published | Yes |
| Spend limits | Not published | No | Yes |
| Usage per sandbox (API) | No | No | Yes |
| Audit logs | Yes | Yes | No |
| SSO | Yes | Yes | No |
| SOC 2 | Not published | Yes | No |
| HIPAA | Not published | No | No |
| EU data residency | No | Yes | Yes |
| Zero data retention | Not published | Not published | Yes |
Performance
On the hpc-sandbox-benchmarks Node.js build-and-test loop at 4 vCPU / 8 GB, boat did 26.69 runs per second and Freestyle did 9.64, so boat finished about 2.8 times as much CPU work. There is no comparable measurement for Koyeb: it was not part of that run. Koyeb publishes a CPU share of at least 0.25 dedicated vCPU per GB of memory, bursting to all cores.
Node.js build-and-test loop at 4 vCPU / 8 GB, higher is better. Measured with the open hpc-sandbox-benchmarks suite. Koyeb has 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 | Freestyle, a month | Koyeb, 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 | $27 · Free | $29 · Pro | $20 · $20/mo |
| One agent that never stops 4 vCPU / 8 GB, 50 GB disk, running 24/7 all month | $159 · Free | $57 · Pro | $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 | $2,139 · Pro | $475 · Pro | $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 | $581 · Pro | $329 · Scale | $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 | $1,305 · Pro · with limits | $485 · Scale · with limits | $2,000 · $2000/mo · with limits |
Freestyle: Freestyle bills per second for the vCPU, RAM and disk allocated to a VM, busy or idle, after monthly allowances that are hard stops on Free. Hobby and Pro set a $50 or $500 monthly minimum that counts as usage, and a paused VM bills only for storage.
Koyeb: Koyeb bills each instance per second at a fixed price per instance type, and deep sleep costs nothing. Pro costs $29 a month with $10 of usage included and Scale $299 with $100 included; the rest of the fee is not credit.
Koyeb: Plans start at $20 a month, and the whole fee is usage credit. You pay per second while a sandbox runs, and a stopped sandbox costs nothing and keeps its disk.
Limits in those scenarios
Freestyle has no idle timeout by default, so a VM bills until you pause it, and on Free the monthly allowances are hard stops. Its Pro plan caps you at 400 concurrent VMs, which is why it does not fit 1,000 short jobs at once. Koyeb's priced shape is eco-xlarge, with a 20 GiB disk and no published price for more, and eco CPUs are throttled above half of each vCPU, so it does not fit that burst either. boat does not fit it as priced: its $2,000 plan queues starts above 90 a minute.
| Scenario | Freestyle | Koyeb | 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 | None that bite |
| Sandboxes for your users | None that bite | None that bite | None that bite |
| 1,000 short jobs at once |
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Which one should you use?
Use Freestyle when
each agent needs a full Linux machine with nested virtualization, when VMs must pause with their memory or fork while running, or when you want a default-deny firewall per VM.
- A whole Linux machine. For agents that need systemd, Docker and nested virtualization, Freestyle gives each one a full KVM VM with its own kernel.
- Memory pause and live fork. For VMs that sleep between requests: they resume the same processes, and you can clone one while it runs.
- Fine network controls. Every VM starts with no network access, and you allow exactly the IPs, VMs, VPCs or domains it may reach.
Use Koyeb when
your sandboxes need GPUs, sleep most of the time and must wake on a request, or have to run in the US or Asia.
- GPUs in the same platform. Useful when an agent or eval needs a GPU: Koyeb runs instances from RTX 4000 cards up to H100 and H200.
- Many regions. Good for sandboxes that must run close to users in the US or Asia as well as the EU.
- Idle sandboxes sleep for free. A sandbox can scale to zero after 5 idle minutes, costs nothing in deep sleep, and wakes on the next request.
Where boat fits
If your agents do hours of real work, like builds, tests, Docker, emulators and a browser, look at boat. It gives each agent a full VM on faster CPUs, with a desktop, hosting and the coding agents built in, and its disk stays when it stops.
Faster CPUs for builds and tests
boat did 26.69 runs per second on the CPU benchmark, Freestyle 9.64, so each install or test takes Freestyle almost three times as long. Koyeb was not measured, and its eco instances guarantee only half of each vCPU.
A desktop and browser, ready
Computer-use and browser agents need a screen. On Freestyle you build GNOME or Xvfb, VNC and Chromium into your own snapshot, and Koyeb sandboxes have no desktop at all. boat streams one at 60fps in every sandbox.
Agents and keys handled from outside
On Freestyle you start agent CLIs through exec and parse their output; on Koyeb keys sit in environment variables the agent can read. boat lets you prompt and steer agents by API and keeps keys in a proxy.
Use boat when your agents do real work for hours: builds, tests, Docker, emulators, a desktop and a browser, on fast CPUs, with a disk that stays and an API to drive the agents inside from outside. Compare it one to one: boat vs Freestyle and boat vs Koyeb.
Questions people ask
Is Freestyle cheaper than Koyeb?
Only for one coding agent on workdays, at $27 against $29 a month. For one agent that never stops it is $159 on Freestyle against $57 on Koyeb, and for 50 agents in parallel $2,139 against $475. boat costs $26 and $317 for those two.
Which is faster, Freestyle or Koyeb?
Only Freestyle was measured: 9.64 runs per second on the hpc-sandbox-benchmarks CPU test at 4 vCPU / 8 GB, against 26.69 for boat. Koyeb was not part of that run, and its eco instances guarantee half of each vCPU.
Can Freestyle and Koyeb run Docker and Android emulators?
Freestyle runs Docker from boot with systemd and full KVM support, so Android emulators work. Koyeb sandboxes start from any Docker image, but Koyeb does not document nested virtualization. boat exposes /dev/kvm and runs Docker inside every sandbox.
Do Freestyle or Koyeb have GPUs?
Koyeb runs instances from an RTX 4000 SFF Ada up to H100 and H200, billed per second. Freestyle offers private GPU sandboxes only on Enterprise. boat is CPU only.
Do sandboxes keep their files?
A Freestyle VM keeps its disk and can pause with its memory, and it bills for that storage. On Koyeb the local disk is lost on redeploy, so lasting files need a volume (in preview) or an SDK snapshot. boat keeps the disk, saves it every minute, and a stopped sandbox costs nothing.
Is boat SOC 2 compliant?
SOC 2 is in progress. We're open about where we stand: live status at status.ascii.dev and our data retention policy at docs.boat.dev/data-retention.
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