Northflank vs Freestyle
Northflank runs sandboxes as Kata microVMs inside a broad cloud platform with GPUs, many regions and your own cloud. Freestyle sells full Linux VMs that pause with their memory, fork while running and wake on the next request, from a single named data center in San Jose, US.
The companies and products
Northflank
Northflank is a London developer platform for running services, jobs and databases on Kubernetes, and Sandboxes is its product for running untrusted code.
A Northflank sandbox is a container image deployed as a service: CPU sandboxes run in Kata microVMs with their own kernel, and GPU sandboxes run under gVisor. You create and drive them from the JavaScript or Python SDK, the CLI or the dashboard, on Northflank's cloud or inside your own. It suits teams that already want one platform for apps, databases, GPUs and sandboxes.
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.
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. “38th cheapest of 377” means 37 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 | Northflank: price rank | Freestyle: price rank | bochka: price rank |
|---|---|---|---|
| Software factory 100 at once · 4 vCPU / 8 GB · 2,200 sessions of 8 h a month A coding agent installs packages all over the disk: Freestyle keeps the whole disk and memory on pause, Northflank keeps only attached volumes, and bochka keeps the whole disk on faster CPUs. | 159th of 367, with limits $1,477 a month | 241st of 367, with limits $3,311 a month | 3rd cheapest of 367 $634 a month |
| Always-on AI employees 50 machines 24/7 · 2 vCPU / 4 GB | 173rd of 366, with limits $1,365 a month | 263rd of 366, with limits $4,195 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 Short code runs suit both: Northflank has small per-second plans from a tenth of a vCPU, and Freestyle VMs pause with their memory and wake on the next request. | 84th of 345, with limits $115 a month | 40th cheapest of 345 $482 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 Freestyle wakes a paused user VM when traffic reaches it and allows 400 at once on Pro; Northflank does not publish how many sandboxes can run at once. | 89th of 361, with limits $815 a month | 16th cheapest of 361 $1,358 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, which suits rollouts that branch from one state. | 342nd of 360, with limits $1,762 a month | 107th of 360, with limits $6,600 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 | 134th of 364, with limits $689 a month | 53rd cheapest of 364 $1,046 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 Northflank's per-second plans fit CI jobs well; Freestyle's own docs say CPU-heavy jobs like kernel builds are better served elsewhere. | 38th cheapest of 377 $352 a month | 168th of 377, with limits $625 a month | 4th cheapest of 377 $86 a month |
| 24/7 dev boxes 1 machine 24/7 · 4 vCPU / 8 GB | 151st of 368, with limits $59 a month | 98th cheapest of 368 $151 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 ships a desktop: on both you build and stream one yourself, while bochka has a 60fps Linux desktop and computer use in every sandbox. | 151st of 369, with limits $371 a month | 234th of 369, with limits $940 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 Northflank has no browser product and Freestyle has a guide to install Chromium and a display yourself; bochka has Chromium ready inside. | 200th of 367, with limits $194 a month | 257th of 367, with limits $482 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 | 196th of 346, with limits $117 a month | 278th of 346, with limits $482 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 | 83rd of 338, with limits $2,049 a month | 183rd of 338, with limits $6,560 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 | 141st of 360, with limits $99 a month | 272nd of 360, with limits $482 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 Northflank has GPU sandboxes from L4 to H100 and up; Freestyle offers private GPU sandboxes only on Enterprise, and bochka is CPU only. | 4th cheapest of 98 $693 a month | 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 | Northflank | Freestyle | bochka |
|---|---|---|---|
| Isolation | Kata microVM with its own kernel for CPU; gVisor for GPU | Full KVM VM with its own kernel on bare metal servers | Full VM with its own kernel on dedicated AMD Ryzen 9 9950X hosts |
| CPU benchmark (4 vCPU / 8 GB) | Not measured on this test | 9.64 runs/s | 26.69 runs/s |
| What survives a stop | Only attached volumes, which bill while paused; the rest of the disk and all processes reset | Pause saves memory and disk; the same processes resume where they left off | The whole disk, saved every minute and on stop; stopped sandboxes cost nothing |
| Snapshots and fork | Filesystem snapshots of a running or stopping sandbox, opt-in; restore into a new one | Clone a running VM without pausing it; snapshots capture memory and disk | Automatic disk snapshots; fork a running sandbox |
| Wake on request | No; no idle auto-pause, a sandbox bills until you pause it | Yes; a VM paused by idle timeout resumes on the next traffic | No; a stopped sandbox is started by API |
| Docker and nested virtualization | Docker runs inside; nested virtualization not documented | Root, systemd as pid 1, Docker from boot, full KVM support | Root, systemd, Docker, and /dev/kvm for Android emulators and VMs |
| Biggest machine | Up to 20 vCPU / 40 GB, more on request; a resize restarts the sandbox | Up to 32 vCPU / 64 GiB on Pro, 64 / 128 with custom limits | Up to 16 vCPU / 32 GB on the $100 plan and above |
| Desktop and browser | Headless; access by SDK, browser terminal or SSH | Guides to install GNOME or Xvfb, VNC and Chromium yourself | 60fps Linux desktop, Chromium and computer use built in |
| Coding agents | Harnesses with Claude Code, Codex, Cursor, OpenCode or Pi, reached by terminal or SSH | claude, codex, opencode and openclaw preinstalled, driven through exec or a terminal | Seven agents preinstalled, with a prompt, steer and events API |
| Keeping API keys out of the sandbox | Header injection for listed hosts in the network policy API | Credentials injected at the edge for HTTPS headers, Postgres and S3 | Credentials proxy for model providers and any HTTPS API; switch a credential to another account when credits run out |
| Outbound rules | Network policies with allow lists by IP, CIDR or domain | Default-deny firewall with allow rules by IP, VM, VPC or exact domain | Open internet, no provider-side allowlist |
| GPUs | L4, A100, H100, RTX PRO 6000 and more, billed per hour | Private GPU sandboxes on Enterprise only | No |
| Regions | US, Canada, Brazil, UK, EU, Switzerland, Asia, Australia and South Africa | Not listed; the docs name a San Jose, US data center | EU only (Germany, Finland, France) |
| Your own cloud | Run on AWS, GCP, Azure and others, or the control plane in your VPC on Enterprise | No | No |
Every feature Battleships tracks (43)
| Feature | Northflank | Freestyle | bochka |
|---|---|---|---|
| Full VM (own kernel) | Yes | Yes | Yes |
| Docker inside | Yes | Yes | Yes |
| Nested virtualization | No | Yes | Yes |
| Root | Not published | Yes | Yes |
| Systemd | Not published | Yes | Yes |
| Desktop GUI | No | No | Yes |
| Browser | No | No | Yes |
| Computer-use API | No | No | Yes |
| SSH | Yes | Yes | 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 | No | Yes | No |
| Custom image (Docker or snapshot) | Yes | Yes | Yes |
| ≥24 h sessions | Yes | Yes | Yes |
| Idle auto-stop | No | Yes | No |
| Wake on request | No | 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 | Yes | Yes |
| Secret proxy for any API | Yes | Yes | Yes |
| Preinstalled agents | Yes | Yes | Yes |
| Agent harness API | No | No | Yes |
| MCP server | No | No | No |
| GPU | Yes | Yes | No |
| Windows | No | No | No |
| Arm64 | Yes | No | No |
| Self-hosting | Yes | No | No |
| BYOC | Yes | No | No |
| Open source | No | No | No |
| Scoped API keys | Not published | Yes | Yes |
| Spend limits | Not published | Not published | Yes |
| Usage per sandbox (API) | Yes | No | Yes |
| Audit logs | Yes | Yes | No |
| SSO | Yes | Yes | No |
| SOC 2 | Yes | Not published | No |
| HIPAA | Yes | Not published | No |
| EU data residency | Yes | No | 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, Freestyle did 9.64 runs per second and bochka did 26.69, so bochka did about 2.8 times as much CPU work in the same time. Northflank has no result on this test, so there is no comparable CPU score for it. This measures CPU speed only, not start time.
Node.js build-and-test loop at 4 vCPU / 8 GB, higher is better. Measured with the open hpc-sandbox-benchmarks suite. Northflank 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 | Northflank, a month | Freestyle, a month | bochka, 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 | $32 · Developer Sandbox (free tier) · with limits | $27 · Free | $20 · $20/mo |
| One agent that never stops 4 vCPU / 8 GB, 50 GB disk, running 24/7 all month | $108 · Developer Sandbox (free tier) · with limits | $159 · Free | $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 | $1,322 · Developer Sandbox (free tier) · with limits | $2,139 · 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 | $361 · Developer Sandbox (free tier) · with limits | $581 · Pro | $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 | $688 · Developer Sandbox (free tier) · with limits | $1,305 · Pro · with limits | $2,000 · $2000/mo · with limits |
Northflank: Northflank bills per second for the plan size you pick, with no monthly fee, until you pause the sandbox; there is no idle auto-pause. Volumes cost $0.15 per GB a month even while paused, and outbound traffic costs $0.06 per GB.
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. Free stops at those allowances; Hobby and Pro set a $50 or $500 monthly minimum that counts as usage, and a paused VM bills only for storage.
Freestyle: 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 whole disk.
Limits in those scenarios
On Northflank the limit that bites in every scenario is what survives a stop: only attached volumes keep their files, so packages installed anywhere else reset, and it does not publish how many sandboxes can run at once. Freestyle keeps the whole VM but has no idle timeout by default, so a VM bills until you pause it, and Pro caps you at 400 VMs at once, which is why it does not fit 1,000 short jobs at once. bochka does not fit that one either: even its $2,000 plan queues starts above 90 a minute.
| Scenario | Northflank | Freestyle | bochka |
|---|---|---|---|
| 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 Northflank when
you need GPUs next to the agent, regions outside the US, or sandboxes inside your own cloud account next to the rest of your apps.
- GPUs next to the code. For agents that train or run models: Northflank has GPU sandboxes from L4 to H100 and up, billed per hour.
- Regions around the world. For users outside the US: Northflank runs in Europe, Asia, Australia, South America and Africa as well as North America.
- Your own cloud, one platform. For teams that must run in their own AWS, GCP or Azure account, next to their services, jobs and databases.
Use Freestyle when
your VMs sleep between requests and must resume with their memory, when you fork running VMs, or when you need a default-deny firewall per VM.
- Memory pause and wake on request. For VMs that sleep between requests: they resume the same processes and wake on the next incoming traffic.
- The whole VM comes back. For agents that install things anywhere: a paused Freestyle VM keeps its whole disk, not only mounted volumes.
- Live fork and bigger machines. For branching work: clone a running VM with its memory, on machines up to 32 vCPU / 64 GiB on Pro.
Where bochka fits
If your agents do hours of builds, tests and browsing on one machine, look at bochka. It keeps the whole disk like Freestyle, runs on CPUs measured almost three times faster, and adds a desktop, a browser and an API to drive the agents inside from outside, which neither Northflank nor Freestyle ships.
Fast CPUs for builds and tests
bochka did 26.69 runs per second on the CPU benchmark and Freestyle did 9.64, and Freestyle's docs send sustained heavy CPU work elsewhere. Northflank has no result on this test, so its speed is unknown.
A desktop and a browser, ready
Both Northflank and Freestyle are headless. A computer-use or browser agent needs you to build an image with a desktop, a browser and a stream, then the screenshot and click layer, and keep it working.
Agents driven from your code
On both, you reach the coding agent through a terminal, SSH or exec and parse its output yourself. bochka sends prompts, steers mid-task and streams events through one API, and its proxy swaps a credential when credits run out.
Use bochka when your agents work on one machine for hours: installs, Docker, emulators, a desktop and a browser, on fast CPUs, with the agents inside driven from your code. Compare it one to one: bochka vs Northflank and bochka vs Freestyle.
Questions people ask
Is Northflank cheaper than Freestyle?
In four of the five scenarios on this page, yes: one agent that never stops is $108 a month on Northflank against $159 on Freestyle. For one coding agent on workdays Freestyle is cheaper, $27 against $32. On Northflank those prices assume only attached volumes keep their files.
Which is faster, Northflank or Freestyle?
Freestyle did 9.64 runs per second on the hpc-sandbox-benchmarks CPU test at 4 vCPU / 8 GB; Northflank has no result on that test, so they cannot be compared there. bochka did 26.69 on the same test.
Does a sandbox keep its files when paused?
On Freestyle, yes: a pause saves the whole disk and memory, and the same processes resume. On Northflank only files on attached volumes survive; the rest of the disk and all processes reset. bochka keeps the whole disk on every stop.
Can Northflank and Freestyle run Docker?
Yes, both give each sandbox its own kernel and Docker runs inside. Freestyle also supports nested virtualization for VMs and Android emulators; Northflank does not document it inside a sandbox. bochka exposes /dev/kvm too.
Which one has GPUs?
Northflank has GPU sandboxes from L4 to H100 and more, billed per hour. Freestyle offers private GPU sandboxes only on Enterprise. bochka runs on CPUs only.
Where do they run?
Northflank runs in many regions across the US, Europe, Asia, Australia, South America and Africa, or in your own cloud. Freestyle does not list regions; its docs name a San Jose, US data center. bochka runs in the EU only.
Try bochka
Install the CLI, then run bochka new.
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