nowfound

AI · alternatives · 2026

24 alternatives to npm i -g hotcell

Hi HN! Sina here. i wanted to share this open source project (apache 2.0) that i've been working on for the past month or so. it's called hotcell and it lets you create/pause/manage sandboxes on any device (your laptop, linux vm, bare metal). i've tested it against various benchmarks that i found on computesdk (https://www.computesdk.com/benchmarks/sandboxes/) as well as the one shared by dax (cofounder of open code) on twitter recently (link to his original thread and my reply https://x.com/sinasanm/status/2078158598996443346) and…

Below are 24 products that do a similar job, ranked by how close each is in meaning and then by launch-day votes.

  1. 1

    Hi HN! Thanks for your attention to my post. It was a big challenge to run most of Node.js packages in browser, fast moreover. Virtual File system, resolve import/export. I got cold many times, depressions, burned out, yet still alive and finished it. Many guys helped me with an advice. Many users give a lot of positive feedback. There are 200,000 monthly unique users. I work full time now because of the freemium business model. To be honest - I am happy after many years of hard work.

    2022 · playcode.io · its alternatives →

  2. 2

    I wanted to see how fast an isolated code sandbox could start if I never had to boot a fresh VM. So instead of launching a new microVM per execution, I boot Firecracker once with Python and numpy already loaded, then snapshot the full VM state. Every execution after that creates a new KVM VM backed by a `MAP_PRIVATE` mapping of the snapshot memory, so Linux gives me copy-on-write pages automatically. That means each sandbox starts from an already-running Python process inside a real VM, runs the code, and exits. These are real KVM VMs, not containers: separate guest kernel, separate guest…

    Mar 2026 · github.com · its alternatives →

  3. 3

    Minimalist, dependency-free virtual machine sandbox for microcontrollers and other resource-constrained devices. Single C file, no dynamic memory allocations, asynchronous design, pure C99 - ringtailsoftware/uvm32

    Dec 2025 · github.com · its alternatives →

  4. 4OS

    I've been working on this for some time now, starting with vm2, then deno-core for 2 years, and recently rewrote it on rusty_v8 with Claude's help. OpenWorkers lets you run untrusted JS in V8 isolates on your own infrastructure. Same DX as Cloudflare Workers, no vendor lock-in. What works today: fetch, KV, Postgres bindings, S3/R2, cron scheduling, crypto.subtle. Self-hosting is a single docker-compose file + Postgres. Would love feedback on the architecture and what feature you'd want next.

    Jan 2026 · openworkers.com · its alternatives →

  5. 5

    Hey HN, I am proud to show you guys that I have built an open source alternative to Azure OpenAI services. Azure OpenAI services was born out of companies needing enhanced security and access control for using different GPT models. I want to build an OSS version of Azure OpenAI services that people could self host in their own infrastructure. "How can I track LLM spend per API key?" "Can I create a development OpenAI API key with limited access for Bob?" "Can I see my LLM spend breakdown by models and endpoints?" "Can I create 100 OpenAI API keys that my students could use in a classroom…

    2023 · github.com · its alternatives →

  6. 6IB

    I've been working on an MMORPG that is now in alpha as a solo developer. Here are the major open source technologies that I use: Blender - 3D modeling software for creating the overall environment and every game object. I've gotten a lot of CC and Public Domain assets from https://poly.pizza GLTF - I export assets from blender to the GLTF asset format JSON - I write a JSON config for every game object that describes things like its name, its interactions, its collisions, etc. Node.js exporter - I iterate over the environment and every asset to create a scene hierarchy. I use…

    2024 · alpha.reconquer.online · its alternatives →

  7. 7

    I'm excited to introduce Zerobox, a cross-platform, single binary process sandboxing CLI written in Rust. It uses the sandboxing crates from the OpenAI Codex repo and adds additional functionalities like secret injection, SDK, etc. Watch the demo: https://www.youtube.com/watch?v=wZiPm9BOPCg Zerobox follows the same sandboxing policy as Deno which is deny by default. The only operation that the command can run is reading files, all writes and network I/O are blocked by default. No VMs, no Docker, no remote servers. Want to block reads to /etc? zerobox…

    Mar 2026 · github.com · its alternatives →

  8. 8

    A self-hostable Wasm sandbox for JavaScript workers.

    Jun 2026 · kyushu.dev · its alternatives →

  9. 9

    Hi all, This project release is a long time coming. It was a big uphill battle, and by far my largest endeavor so far. I built it for Sandstorm because I believe in Sandstorm's model, and I wanted to show that there's still life and potential in it. If you're inspired, joining our OpenCollective would be really helpful: https://opencollective.com/sandstormcommunity (keeping in mind that Sandstorm has now moved from its original leadership to a community project https://sandstorm.org/news/2023-11-03-from-io-to-org). You can also join our mailing list or…

    2023 · sandstorm.org · its alternatives →

  10. 10

    WASM sandbox for running LLM-generated code safely. Agents get a bash-like shell and can only call tools you provide, with constraints you define. No Docker, no subprocess, no SaaS — just pip install amla-sandbox

    Jan 2026 · github.com · its alternatives →

  11. 11

    I built Magic Sandbox, an AI app platform where your AI assistant can directly interact with Magic Sandbox apps published by the community. Check out the demo video to see it in action: https://www.loom.com/share/4a1d4aee83a5485197898f537e1cb397 Or head to https://magicsandbox.ai to go through the onboarding tutorial. Originally I set out to build a monetized version of OpenAI’s custom GPTs, where developers would earn money when users used their custom GPT. Eventually this evolved into a platform for AI powered apps, which expose not only context and…

    2025 · magicsandbox.ai · its alternatives →

  12. 12

    Hi HN, we built SuperHQ, an open source app that runs AI coding agents in isolated microVM sandboxes instead of directly on your machine. Each agent gets its own VM with a full Debian environment. You mount your projects in, writes go to a tmpfs overlay so your host is never touched, and you get a diff view to accept or discard changes. API keys never enter the sandbox. We also just launched remote.superhq.ai which acts as a remote control for SuperHQ, allowing you to access your workspaces and agents from anywhere.

    Apr 2026 · github.com · its alternatives →

  13. 13

    High performance secure & portable Rust functions in Node.js

    2020 · secondstate.io · its alternatives →

  14. 14
    SuperHQ▲95

    Hey HN, I built SuperHQ, an app that lets you run coding agents in local sandboxes (powered by Shuru). No custom UI wrapping the agents, they run as CLI/TUI like they were designed to. It just provides you the tools most of us (okay, maybe just me?) needed for running multiple coding agents in parallel without worrying about breaking your system or work environment. Each agent runs in its own microVM. You mount your projects in, writes go to a tmpfs overlay so your host is never touched, and you get a unified diff view to accept or discard changes. API keys never enter the sandbox, they…

    Apr 2026 · superhq.ai · its alternatives →

  15. 15

    Over the past few months, as we scaled our internal AI Agents, we hit a dead end: Running LLM-generated arbitrary code in Docker is basically running naked on security due to container escape risks. But using full traditional VMs takes minutes to boot and eats too much memory to support high-density concurrency. We loved the developer experience of SaaS sandboxes on the market, but they are closed-source, expensive, and have too high a barrier to entry for self-hosting. So, our team decided to build our own. After months of grinding, using RustVMM and KVM, we built a blazing-fast,…

    Apr 2026 · github.com · its alternatives →

  16. 16

    A better way to run a personal server

    2015 · sandstorm.io · its alternatives →

  17. 17

    "Game" is a stretch, but I put together this repo containing a pure Rust app which uses SDL2 and compiles to WASM (and can be run in a browser). Older resources were a bit out of date and a bit too verbose for my purposes, so here's a minimal working example.

    2024 · github.com · its alternatives →

  18. 18

    One TypeScript SDK for every sandbox provider

    Jul 2026 · sandbox-sdk.app · its alternatives →

  19. 19

    We’ve been working with automating coding agents in sandboxes as of late. It’s bewildering how poorly standardized and difficult to use each agent varies between each other. We open-sourced the Sandbox Agent SDK based on tools we built internally to solve 3 problems: 1. Universal agent API: interact with any coding agent using the same API 2. Running agents inside the sandbox: Agent Sandbox provides a Rust binary that serves the universal agent API over HTTP, instead of having to futz with undocumented interfaces 3. Universal session schema: persisting sessions is always problematic, since…

    Jan 2026 · github.com · its alternatives →

  20. 20OS

    Kshitij and Rahul here. We're building Playground, an open-source sandbox that lets your non-technical teams prototype directly on production codebases, without bugging you (developers) to spin up and maintain another repo. The repo is here: https://github.com/B1u3B01t/design-playground. We've been working together for six years. Last year we built an AI design agent because we thought designers were the biggest bottleneck. But we were wrong. After talking to teams, we realised designers, PMs, founders and even sales people all wanted to quickly change and explore flows…

    Jul 2026 · its alternatives →

  21. 21

    Run untrusted code safely at scale

    2025 · modal.com · its alternatives →

  22. 22

    Introducing Sphere - A lightweight, sandboxed compute runtime written in Rust. - introducing-sphere.md

    2025 · gist.github.com · its alternatives →

  23. 23

    Hi, over the past few months I've been working on this project: Numax is a small Rust runtime that does three things: it runs WebAssembly modules in a sandbox, has a built-in local key-value store, and syncs everything across nodes with CRDTs and gossip. Basically, you write a wasm module, run it on two machines, and they converge (I hope !). It's a decentralized system... I hope someone finds it interesting! There's a whitepaper I've put a lot into, and I think the code isn't bad either! I believe there's still room in this world for software that's fun and well made, and while building…

    Jun 2026 · github.com · its alternatives →

  24. 24SJ

Also compare

Ranked by how close each launch is in meaning, then by votes. Prices were read from each product’s own site when checked and can change. Refine with your own description →