Freestyle vs Unikraft Cloud
Freestyle gives each agent a full Linux VM with systemd, Docker and nested virtualization, billed per second. Unikraft Cloud turns a Dockerfile into a small microVM that sleeps when idle and wakes in milliseconds, sold as flat monthly pools.
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.
Unikraft Cloud
Unikraft Cloud is a microVM cloud from Unikraft Inc. that runs any Dockerfile-based workload as a minimal Linux microVM with millisecond cold starts and scale-to-zero.
Your Dockerfile becomes the VM image at build time, and each instance runs on a heavily customized Firecracker VMM, so it boots in milliseconds and can go into standby when no traffic arrives. It is a general compute platform built for dense, bursty work such as HTTP services, headless browsers and agent fleets, sold as flat self-serve plans plus Enterprise dedicated hosts, on-prem and bring your own cloud. It is not a dev machine you log into: instances are reached through services, the CLI and a sandbox plugin for commands and files.
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 | Unikraft Cloud: 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 runs Docker, databases and test suites inside the sandbox; Freestyle supports that, Unikraft documents no container runtime inside an instance, and boat runs it on faster CPUs. | 241st of 367, with limits $3,311 a month | Can't run it | 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 | Can't run it | 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 Short code runs that sleep between calls suit both: Freestyle resumes paused VMs with their memory, and Unikraft wakes instances in milliseconds but caps self-serve plans at 24 running. | 40th cheapest of 345 $482 a month | Can't run it | 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 Freestyle Pro runs up to 400 VMs at once, while Unikraft Pro holds 5,000 sleeping instances but only 24 running ones, so hundreds of active users need its Enterprise plan. | 16th cheapest of 361 $1,358 a month | Can't run it | 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 | 107th of 360, with limits $6,600 a month | Can't run it | 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 | Can't run it | 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 jobs that build images or run emulators need Docker and /dev/kvm; Freestyle has both on every plan, Unikraft keeps nested virtualization for Enterprise, and boat did 2.8 times Freestyle's CPU work. | 168th of 377, with limits $625 a month | Can't run it | 4th cheapest of 377 $86 a month |
| 24/7 dev boxes 1 machine 24/7 · 4 vCPU / 8 GB Unikraft's Team pool is the cheaper way to keep one box up all month, but it has no SSH yet; Freestyle and boat both let you log in. | 98th cheapest of 368 $151 a month | 219th of 368, with limits $39 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 Freestyle nor Unikraft ships a desktop, so you build the display and click layer yourself; boat streams a Linux desktop at 60fps with computer use built in. | 234th of 369, with limits $940 a month | Can't run it | 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 Freestyle has guides to install Chromium and a display, and Unikraft runs headless browsers you package in your image; boat has Chromium on a desktop in every sandbox. | 257th of 367, with limits $482 a month | Can't run it | 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 | Can't run it | 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 | Can't run it | 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 | Can't run it | 2nd cheapest of 360 $200 a month |
| GPU eval jobs 10 at once · 8 vCPU / 32 GB · 500 sessions of 30 min a month | Can't run it | Can't run it | 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 | Unikraft Cloud | boat |
|---|---|---|---|
| Isolation | Full KVM VM with its own kernel on bare metal servers | Minimal Linux microVM on a customized Firecracker VMM | Full VM with its own kernel on dedicated AMD Ryzen 9 9950X hosts |
| CPU benchmark (4 vCPU / 8 GB) | 9.64 runs/s | Not measured | 26.69 runs/s |
| Docker and systemd inside | Yes; systemd is pid 1 and Docker runs from boot | The Dockerfile becomes the VM image; no container runtime inside is documented | Yes, Docker, systemd and root, like any Ubuntu machine |
| Nested virtualization | Yes, full KVM support | Enterprise only, with a per-instance flag and permission | Yes, /dev/kvm for Android emulators and VMs on every plan |
| SSH | Yes | Not yet; commands and files go through the sandbox plugin and CLI | Yes, into every sandbox |
| Biggest machine | Up to 32 vCPU / 64 GiB on Pro, 64 / 128 with custom limits | Plan pool shared by all running instances: 2 vCPU / 4 GiB, 8 / 8 or 24 / 32 | Up to 16 vCPU / 32 GB per sandbox on the $100 plan and above |
| Running at once, self-serve | 10 on Free, 40 on Hobby, 400 on Pro | 2 on Hobby, 8 on Team, 24 on Pro | 100 to 2,000 sandboxes at once on paid plans |
| Idle, standby and wake on request | Pause saves memory and disk; a paused VM wakes on the next traffic | Standby after a 1 second idle cooldown by default; wakes in milliseconds, with memory kept in stateful mode | Disk saved every minute and on stop; a stopped sandbox is started again by API |
| Fork and checkpoints | Clone a running VM without pausing it; snapshots capture memory and disk | Checkpoint a running microVM's memory and volumes with a pause of a few milliseconds, then start new instances from it | Fork a running sandbox with its disk |
| Desktop, browser and computer use | Guides to install GNOME or Xvfb, VNC and Chromium yourself | None built in; you can run your own headless browser from a Dockerfile | 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 | None preinstalled; you bring the agent in your own image | 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 | Network shield can inject secrets into traffic, Enterprise only, limited access | Credentials proxy for model providers and any HTTPS API, on every plan; switch a credential to another account when credits run out |
| Outbound rules | Default-deny firewall with allow rules by IP, VM, VPC or exact domain | Network shield filters traffic, Enterprise only, limited access | Open internet, no provider-side allowlist |
| Regions | Not listed; the docs name a San Jose, US data center | Dallas, Frankfurt, San Francisco, Singapore and Washington DC; more on request | EU only (Germany, Finland, France), zero data retention |
Every feature Battleships tracks (43)
| Feature | Freestyle | Unikraft Cloud | boat |
|---|---|---|---|
| Full VM (own kernel) | Yes | Yes | Yes |
| Docker inside | Yes | No | Yes |
| Nested virtualization | Yes | Yes | Yes |
| Root | Yes | Yes | 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 | Yes | 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 | Not published | Yes |
| Public IPv4 | No | No | No |
| Egress allowlist | Yes | Yes | No |
| Secret proxy | Yes | Yes | Yes |
| Secret proxy for any API | Yes | Yes | Yes |
| Preinstalled agents | Yes | No | Yes |
| Agent harness API | No | No | Yes |
| MCP server | No | No | No |
| GPU | Yes | Yes | No |
| Windows | No | No | No |
| Arm64 | No | Yes | 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 | Not published | Yes |
| Usage per sandbox (API) | No | No | Yes |
| Audit logs | Yes | Yes | No |
| SSO | Yes | No | No |
| SOC 2 | Not published | Yes | No |
| HIPAA | Not published | Yes | 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. Unikraft Cloud has no comparable measurement. Both advertise fast starts, about 65 ms for Freestyle and under 10 ms for Unikraft, but those are their own figures and measure start time, not CPU speed.
Node.js build-and-test loop at 4 vCPU / 8 GB, higher is better. Measured with the open hpc-sandbox-benchmarks suite. Unikraft Cloud 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 | Unikraft Cloud, 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 | $39 · Hobby | $20 · $20/mo |
| One agent that never stops 4 vCPU / 8 GB, 50 GB disk, running 24/7 all month | $159 · Free | $39 · Hobby | $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 | Can't run it | $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 | Can't run it | $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 | Can't run it | $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 of 200 vCPU-hours, 400 GiB-hours of RAM and 60,000 GiB-hours of storage. On Free those allowances are hard stops; Hobby and Pro set a $50 or $500 monthly minimum that counts as usage.
Unikraft Cloud: Unikraft charges a flat monthly fee for a pool of running capacity: free for 2 vCPU / 4 GiB, $39 for 8 vCPU / 8 GiB, $199 for 24 vCPU / 32 GiB, with sleeping instances not counted. It publishes no per-hour rate, so anything bigger is an Enterprise quote.
Unikraft Cloud: 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
Unikraft fits only the single-agent scenarios, on its Team pool, and one 4 vCPU / 8 GB agent fills that pool; 50 agents, sandboxes for your users and 1,000 short jobs need more than any self-serve plan holds. Freestyle fits 50 agents and user sandboxes on Pro, but its 400-VM cap is why 1,000 jobs at once do not fit, and on Free the monthly allowances are hard stops. boat fits the first four, but at 1,000 short jobs at once its plan queues starts above 90 a minute.
| Scenario | Freestyle | Unikraft Cloud | 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 Freestyle when
your agents need a full Linux machine with Docker and KVM that pauses with its memory, a default-deny firewall, or hundreds of VMs at once without a sales call.
- A whole Linux machine per agent. For agents that run containers or emulators: every VM has systemd, Docker and nested virtualization, and coding agent CLIs come preinstalled.
- Big machines and big fleets, self-serve. Pro runs up to 400 VMs at once and VMs up to 32 vCPU / 64 GiB, with no Enterprise contract.
- A firewall on every VM. For teams that must control egress: each VM starts with no network access, and you allow exactly the IPs, VMs or domains it needs.
Use Unikraft Cloud when
you run many small services or headless browsers that sleep most of the time and must wake in milliseconds, need US or Asia regions, or want GPUs or on-prem under Enterprise.
- Millisecond starts and scale-to-zero. Best for many small services that sleep most of the time and must answer the next request in milliseconds.
- A flat monthly pool. For one small agent or service that runs all month, the Team pool is a fixed fee instead of a per-second bill.
- Regions and your own hardware. Unikraft runs in the US, Frankfurt and Singapore, and Enterprise adds GPUs, arm64, dedicated hosts, on-prem or your own cloud.
Where boat fits
If you are choosing between these two for coding or computer-use agents, boat gives each agent a full VM like Freestyle, on faster CPUs, with a desktop, a browser and agents you drive from outside built in. Unlike Unikraft's self-serve pools, paid boat plans run 100 to 2,000 full-size sandboxes at once without a sales call.
Almost three times the CPU speed
On the same Node.js build-and-test benchmark, boat did 26.69 runs per second and Freestyle 9.64, so every install and test takes Freestyle almost three times as long. Unikraft has no published measurement, and its Team pool is 8 vCPU shared by all instances.
A desktop and a browser, ready
Neither Freestyle nor Unikraft ships a desktop. On Freestyle you install GNOME or Xvfb, VNC and Chromium and build the click layer; on Unikraft you bake it all into the image. boat streams one at 60fps with computer use.
Agents you drive from outside, keys kept out
boat lets you prompt, steer and follow the agents inside through one API, and its credentials proxy works on every plan. Freestyle leaves you parsing CLI output from exec, and Unikraft's secret injection is Enterprise only.
Use boat when your agents do real work for hours: builds, tests, Docker, emulators, a desktop and a browser, on fast CPUs, with an API to drive the agents inside from outside. Compare it one to one: boat vs Freestyle and boat vs Unikraft Cloud.
Questions people ask
Is Freestyle cheaper than Unikraft Cloud?
For one coding agent on workdays, Freestyle is $27 a month on Free against $39 a month for Unikraft's Team pool. For one agent that never stops, Unikraft is $39 against $159 on Freestyle. For 50 agents or sandboxes for your users, only Freestyle has a self-serve plan that fits; boat is $20 and $26 a month for the two single-agent cases.
Which is faster, Freestyle or Unikraft Cloud?
For CPU work, only Freestyle was measured: 9.64 runs per second at 4 vCPU / 8 GB, against 26.69 for boat. For start time, Unikraft states cold starts under 10 ms and Freestyle about 65 ms, both their own figures.
Can I run Docker inside Unikraft Cloud?
Unikraft uses your Dockerfile to build the VM's filesystem, and its docs do not describe running a container runtime inside a running instance. Freestyle and boat VMs both run Docker and systemd from boot.
Can I SSH into Freestyle or Unikraft Cloud?
Freestyle VMs support SSH. Unikraft announced SSH as coming soon, and today you run commands and move files through its sandbox plugin and CLI. You can SSH into every boat sandbox.
Do both wake on the next request?
Yes. A Freestyle VM paused by its idle timeout resumes on the next traffic, and a Unikraft instance in standby wakes in milliseconds. A stopped boat sandbox keeps its disk and is started again by API.
Is Unikraft Cloud the same as Unikraft?
No. Unikraft Cloud is the commercial platform from Unikraft Inc., while the Unikraft unikernel project at unikraft.org is a separate open-source project. Unikraft Cloud runs Linux-based microVMs.
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