Namespace vs Replit
Namespace is a build and dev platform: fast CI runners, build caches and Devboxes on Linux, macOS and Windows, which stop after 4 to 24 hours. Replit is an AI app builder: you describe an app, Replit Agent writes it, and Replit hosts it.
The companies and products
Namespace
Namespace is a dev platform for fast builds, tests and coding environments: CI runners, build caches and Devboxes, on its own hardware.
Most of Namespace is CI: a faster drop-in for GitHub Actions runners, with Docker, Bazel, Turborepo and Nix caching. Its Devboxes are remote Linux and macOS machines with persistent storage, made for people and AI coding agents, and they also host sessions for Claude Managed Agents, Cursor Cloud Agents and Devin. It is a different kind of product from boat, so this page compares the part where they overlap: a machine an agent works on.
- Products
- GitHub Actions runners, Docker, Bazel, Turborepo and Nix caching, Devboxes, and a compute API
- Hardware
- Its own hardware in its own racks: AMD EPYC for Linux and Windows, Apple M4 Pro or M5 Max for macOS
- Linux Devboxes
- Run from a container image you choose and include Docker; the docs do not say whether each one has its own kernel
- Funding
- Announced a $42M Series B
- Compliance
- Trust center lists SOC 2 Type II
Replit
Replit is an AI app builder and hosting platform: you describe an app in chat, Replit Agent writes it, and Replit publishes it.
You work in a browser workspace where Replit Agent sets up the project, writes the code, tests it and fixes problems, with system packages managed by Nix. When the app is ready you publish it as an Autoscale, Static, Scheduled or Reserved VM deployment, with Postgres and object storage next to it. It is built for people and teams who want a working app, not for programs that need to create many machines by API, so this page compares the parts where the two overlap.
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. “80th cheapest of 377” means 79 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 | Namespace: price rank | Replit: price rank | boat: price rank |
|---|---|---|---|
| Software factory 100 at once · 4 vCPU / 8 GB · 2,200 sessions of 8 h a month Namespace has a compute API and an MCP server that create Devboxes, while Replit's outside entry point drives Replit Agent one app at a time; boat starts, forks and steers many agents from code. | 39th of 367, with limits $3,495 a month | 181st of 367, with limits $2,000 a month | 3rd cheapest of 367 $634 a month |
| Always-on AI employees 50 machines 24/7 · 2 vCPU / 4 GB Both are a compromise: a Namespace Devbox is shut down after at most 24 hours, and on Replit an assistant that never stops is a Reserved VM, one published app billed all month; boat has no session cap on paid plans. | 303rd of 366, with limits $6,645 a month | 202nd of 366, with limits $2,033 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 bursts cost less on Namespace and Replit than on boat here, because they bill per minute or per request with no plan fee, while boat's start limits make big bursts a compromise. | 247th of 345, with limits $250 a month | 228th of 345, with limits $146 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 Neither is built for 300 machines for your users: Namespace bills each short session in Devbox Minutes, and Replit does not publish how many deployments can run at once. | 284th of 361, with limits $2,068 a month | 233rd of 361, with limits $825 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 | 356th of 360, with limits $9,012 a month | 258th of 360, with limits $4,226 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 | 282nd of 364, with limits $1,043 a month | 265th of 364, with limits $685 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 Namespace is a full fit here because CI runners with Docker, Bazel and Turborepo caches are its main product, while Replit has no runner service and no documented Docker; boat runs CI jobs on full VMs with Docker and /dev/kvm. | 80th cheapest of 377 $765 a month | 275th of 377, with limits $425 a month | 4th cheapest of 377 $86 a month |
| 24/7 dev boxes 1 machine 24/7 · 4 vCPU / 8 GB A Namespace Devbox stops when idle and is shut down after at most 24 hours, and a Replit workspace has no Docker or systemd and no published CPU per plan; a boat machine stays up as long as you want. | 126th of 368, with limits $168 a month | 165th of 368, with limits $109 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 Namespace's screenshot and click API works on macOS Devboxes only, and Replit's VNC pane shows a desktop to a person with no API for an agent; boat streams a 60fps Linux desktop with Chromium. | 67th of 369, with limits $982 a month | 190th of 369, with limits $619 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 | 285th of 367, with limits $789 a month | 229th of 367, with limits $317 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 | 259th of 346, with limits $332 a month | 234th of 346, with limits $217 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 | 226th of 338, with limits $9,012 a month | 150th of 338, with limits $4,378 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 | 242nd of 360, with limits $339 a month | 208th of 360, with limits $215 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 | 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 Only Namespace fits: it runs macOS Devboxes and instances on Apple Silicon, and neither Replit nor boat has macOS. | 6th cheapest of 36 $1,205 a month | Can't run it | Can't run it |
Key features
| Feature | Namespace | Replit | boat |
|---|---|---|---|
| Kind of product | CI runners, build caches, Devboxes and a compute API | AI app builder with browser workspaces and app hosting | Sandboxes you create, stop and fork by API, SDK or CLI |
| Isolation | Linux Devboxes run from a container image on Namespace's own hardware; the docs do not say if each has its own kernel | Not documented; the security page says strong logical separation between users | Every sandbox is a full VM with its own kernel |
| CPU speed (Node.js build-and-test, 4 vCPU / 8 GB) | 21.79 runs/s | Not measured | 26.69 runs/s |
| Docker and nested virtualization | Docker in Linux Devboxes; /dev/kvm on Linux compute instances | System packages come from Nix; the docs do not describe Docker, systemd or /dev/kvm | Docker, root, systemd and /dev/kvm on every machine |
| How long a session can run | Devboxes stop after 4, 5 or 24 hours by plan, raisable to 24 at most | A Reserved VM runs continuously as one published app | No session cap on paid plans |
| Creating machines from code | Compute API, TypeScript SDK and an MCP server to create Devboxes and run commands; no fork | MCP server tools to create, update and publish apps; no API to start many machines | API, SDK and CLI to create, stop, resume and fork many sandboxes |
| Coding agents | Hosts Claude Managed Agents, Cursor and Devin sessions run by those partners | Replit Agent, which you can also drive from an MCP client | Claude Code, Codex, OpenCode and more preinstalled, with a prompt, steer and events API |
| Desktop and computer use | Screenshot and click API on macOS Devboxes only; VNC and RDP for compute instances | VNC pane that streams a native desktop to your browser; no computer-use API | 60fps Linux desktop and Chromium, computer use and browser control, embeddable stream |
| Files after a stop | A stopped Devbox keeps its storage, billed at $0.20 per GB-month used | Workspace files and Agent checkpoints; published apps should not rely on their filesystem | Snapshots every minute and on stop; a stopped sandbox costs nothing |
| Idle stop and wake | Devboxes stop after an idle timeout and start again when you connect | Autoscale starts on the first request and goes idle after 15 minutes | Machines run until you stop them |
| Keeping keys out of the sandbox | Egress rules inject a header from Namespace Vault, resolved outside the workload | Replit manages keys for AI models billed to credits; other keys are secrets in the app | AI credentials proxy for model providers and any HTTPS API you register; switch a credential to another account when credits run out |
| Reaching the machine | HTTPS URLs that need a Namespace login, TCP through a CLI port-forward; no public IP | Published apps on HTTPS domains and custom domains; SSH into the workspace on paid plans | HTTPS URLs for up to 50 ports, token-protected; raw TCP; dedicated IPv6 or IPv4; SSH |
| Outbound rules | Egress policies per Devbox blueprint, runner or instance: block, advisory or allow by domain | No domain allowlist documented | Open internet on every plan; no provider-side allowlist |
| Operating systems | Linux, macOS on Apple Silicon, and Windows on Team plans and up | Linux | Linux only; Wine for Windows apps |
Every feature Battleships tracks (43)
| Feature | Namespace | Replit | boat |
|---|---|---|---|
| Full VM (own kernel) | Yes | Yes | Yes |
| Docker inside | Yes | No | Yes |
| Nested virtualization | Yes | No | Yes |
| Root | Yes | Not published | Yes |
| Systemd | Not published | No | Yes |
| Desktop GUI | Yes | Yes | Yes |
| Browser | No | No | Yes |
| Computer-use API | Yes | No | Yes |
| SSH | Yes | Yes | Yes |
| Persistent disk | Yes | Yes | Yes |
| Pause/resume | Yes | No | Yes |
| Automatic snapshots | Yes | Yes | 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 | 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 | No | No |
| Secret proxy | Yes | Yes | Yes |
| Secret proxy for any API | Yes | No | Yes |
| Preinstalled agents | Yes | Yes | Yes |
| Agent harness API | No | Yes | Yes |
| MCP server | Yes | Yes | No |
| GPU | No | No | No |
| Windows | Yes | No | No |
| Arm64 | Yes | Not published | No |
| Self-hosting | No | No | No |
| BYOC | No | No | No |
| Open source | No | No | No |
| Scoped API keys | Not published | Not published | Yes |
| Spend limits | Yes | Yes | Yes |
| Usage per sandbox (API) | No | Yes | Yes |
| Audit logs | Yes | 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
In StarSling's public run of 2026-09-29, at 4 vCPU / 8 GB, boat did 26.69 Node.js build-and-test runs per second and Namespace did 21.79, so the same build takes about a fifth longer on Namespace. Replit is not in that benchmark, so there is no comparable measurement for it.
Node.js build-and-test loop at 4 vCPU / 8 GB, higher is better. Measured with the open hpc-sandbox-benchmarks suite. Namespace measured on: Linux compute instance (unit-minutes, PAYG/overage $0.0015). Replit 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 | Namespace, a month | Replit, 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 | $50 · Devbox (pay as you go) | $122 · Pro $100 (annual) · with limits | $20 · $20/mo |
| One agent that never stops 4 vCPU / 8 GB, 50 GB disk, running 24/7 all month | $176 · Devbox (pay as you go) · with limits | $122 · Pro $100 (annual) · with limits | $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 | $2,198 · Devbox (pay as you go) | $1,330 · Pro $1,000 (annual) · with limits | $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 | $1,214 · Devbox (pay as you go) | $403 · Pro $250 (annual) · with limits | $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 | $3,237 · Devbox (pay as you go) | $825 · Pro $1,000 (annual) · with limits | $2,000 · $2000/mo · with limits |
Namespace: Devboxes are billed in Devbox Minutes at $0.004 each, pay as you go on every plan; a 4 vCPU / 8 GB Devbox uses one a minute. The minutes in the Team ($100) and Business ($250) plans cover runners and instances, not Devboxes, and stored files cost $0.20 per GB-month.
Replit: Replit plans (Core $20, Pro from $100) turn into monthly credits for Agent work and hosting, then usage is pay as you go. A Reserved VM has a fixed monthly price per size, such as $130 for 4 vCPU / 16 GB, while Autoscale charges $0.60 per million compute units only while it serves.
Replit: 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
On Namespace the limit that bites is time: a Devbox is shut down after 4, 5 or 24 hours by plan, so an agent that never stops restarts at least once a day, and Namespace publishes no Devbox concurrency limit or egress price. Replit is marked as not a fit in every scenario because it is an app platform: each always-on machine is a published Reserved VM that bills all month, and it does not publish how many can run at once or document Docker. On boat, the 1,000-job burst is queued above 90 starts a minute and needs more starts per day than the $2,000 plan allows.
| Scenario | Namespace | Replit | boat |
|---|---|---|---|
| One coding agent, workdays |
|
| None that bite |
| One agent that never stops |
|
| None that bite |
| 50 agents in parallel |
|
| None that bite |
| Sandboxes for your users |
|
| None that bite |
| 1,000 short jobs at once |
|
|
|
Which one should you use?
Use Namespace when
you need faster GitHub Actions runners with build caches, macOS or Windows machines, or Devboxes for people that stop when idle.
- macOS and Windows. Useful if you build iOS or Mac apps or test on Windows: Namespace runs macOS on Apple Silicon and Windows machines.
- CI runners and build caches. Useful if you want faster GitHub Actions: Namespace is a drop-in runner with Docker, Bazel and Turborepo caching.
- Egress rules by domain. Useful if machines must reach only chosen domains: Namespace can block all other outbound traffic, with an advisory mode first.
Use Replit when
you want Replit Agent to build a web app from a description and host it for you, with databases, sleeping when idle, or regions outside Europe.
- An app built and hosted for you. Useful if you want a working app from a description: Replit Agent builds, tests and publishes it with Postgres and storage.
- Hosting that costs nothing when idle. Useful for web apps with uneven traffic: Autoscale wakes on the first request and costs nothing while idle.
- Regions on five continents. Useful if your users are spread out: Replit publishes apps in North America, Europe, Asia, South America and Australia.
Where boat fits
Namespace is built for builds and dev machines, and Replit is built for apps that people describe in a chat. If what you are really running is agents that your own code starts, steers and keeps running for hours or days, look at boat: full Linux VMs by API, with no session cap, Docker and a desktop.
No clock on the session
A Namespace Devbox is shut down after 4, 5 or 24 hours, even mid-task, so your code must restart it. On Replit, staying on means a Reserved VM, one published app billed all month. boat sandboxes run as long as the work does.
A full VM with Docker and KVM
Namespace puts /dev/kvm on compute instances, not Devboxes, and does not say if a Devbox has its own kernel. Replit's Nix setup documents no Docker or systemd. Every boat sandbox has its own kernel, root, systemd, Docker and /dev/kvm.
Agents and a desktop you drive from outside
On Namespace a partner runs the agent loop, or you write it, and its computer-use API is macOS only. Replit's MCP server drives Replit Agent only. boat ships Claude Code, Codex and a 60fps desktop with a prompt, steer and events API.
Use boat when your own code starts agents on Linux for hours or days: a full, faster VM with no session cap, Docker and /dev/kvm, a 60fps desktop, and coding agents you drive from outside. Compare it one to one: boat vs Namespace and boat vs Replit.
Questions people ask
Is Namespace cheaper than Replit?
It depends on the job. One coding agent on workdays comes to $50 on Namespace and $122 on Replit, but one agent running all month comes to $176 on Namespace and $122 on Replit, and 50 agents in parallel come to $2,198 against $1,330. Replit does not fit any of these as is, and boat comes to $20, $26 and $317 for the same three.
Which is faster, Namespace or Replit?
We can only say for Namespace: it did 21.79 Node.js build-and-test runs per second at 4 vCPU / 8 GB in StarSling's public benchmark. Replit is not in that benchmark. boat did 26.69 in the same run.
Can Namespace or Replit run Docker?
Namespace Linux Devboxes include Docker, and Linux compute instances have /dev/kvm. Replit sets up environments with Nix packages and its docs do not describe Docker, systemd or /dev/kvm. Every boat sandbox has root, systemd, Docker and /dev/kvm.
How long can a machine run on Namespace or Replit?
A Namespace Devbox runs up to 4 hours on Developer, 5 on Team and 24 on Business, even while you work in it. A Replit Reserved VM runs continuously, but it is a published app billed all month. boat has no session cap on paid plans.
Can I drive agents on Namespace or Replit from my own code?
Partly. Namespace hosts sessions run by Anthropic, Cursor and Devin, and its MCP server lets your agent create Devboxes and run commands. Replit's MCP server drives Replit Agent only. On boat you prompt, steer and stream events from Claude Code, Codex and other agents inside each sandbox.
Where does my data run?
Namespace runs in several regions and keeping every workload in one region needs its enterprise plan. Replit hosts data mainly on Google Cloud in the United States and publishes apps on five continents. boat runs only in the EU (Germany, Finland and France), with EU data residency.
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