Sandbox.

Blaxel

Blaxel · YC S25

Blaxel's architecture uses EROFS (read-only base filesystem) + tmpfs (RAM-based writable layer) + OverlayFS orchestration, reserving ~50% of available memory for tmpfs. This enables the 25 ms resume benchmark — the fastest in the industry. Standby transitions complete in ~15 seconds, and the system can sustain unlimited standby duration.

Total funding

$7.3M

Seed · Jul 2025

Cold start

<25ms

Standby resume

Regions

16

Global

Team

~6

Co-founders + team

Founded

2024 (core team from ForePaaS / OVHcloud)

Team size

6 co-founders + team

Funding

$7.3M Seed (July 2025) led by First Round Capital, with Y Combinator, Liquid 2, Multimodal

Founders

Paul Sinaï (CEO) — previously CEO of ForePaaS (acquired by OVHcloud); 5 co-founders all from OVH/ForePaaS

Customers

Human Behavior · Vybe · Jazzberry

Isolation

Firecracker microVM · EROFS + tmpfs overlay

Cold start

Sub-25 ms resume from standby

GPU

Yes

Snapshots

save+restore+fork — full filesystem and memory; fork from templates

Storage

Both — volumes + snapshot-based standby

Compliance

SOC 2 Type II · HIPAA BAA · ISO 27001

GitHub

Partial OSS (SDK/CLI)

Last release

Active development as of April 2026

Edge

Industry-fastest resume at 25 ms; perpetual standby with zero compute cost; 16 global regions

E2B

Pending full review.

Founded

2023

Team size

—

Funding

—

Founders

Vasek Mlejnsky (CEO), Tomas Valenta (CTO)

Customers

—

Isolation

Firecracker microVMs

Cold start

—

GPU

—

Snapshots

—

Storage

—

Compliance

—

GitHub

Open-source SDK

Last release

—

Edge

Most popular open-source sandbox SDK for AI agents.

Modal Labs

Pending full review.

Founded

2021

Team size

—

Funding

—

Founders

Erik Bernhardsson (CEO), formerly Spotify ML; Akshat Bubna (Co-Founder)

Customers

—

Isolation

gVisor + container runtimes

Cold start

—

GPU

Yes — A100, H100, L4, T4 on demand

Snapshots

—

Storage

Volumes + Dicts

Compliance

SOC 2

GitHub

—

Last release

—

Edge

GPU-first serverless compute with Pythonic API.

Daytona Platforms

Pending full review.

Founded

2022

Team size

—

Funding

—

Founders

Ivan Burazin (CEO, previously Codeanywhere)

Customers

—

Isolation

Container-based dev environments

Cold start

—

GPU

—

Snapshots

—

Storage

Persistent dev workspaces

Compliance

—

GitHub

Open-core

Last release

—

Edge

Dev environment platform with managed + self-hosted options.

Cloudflare

Pending full review.

Founded

2009

Team size

Publicly traded (NYSE: NET); thousands of employees

Funding

Public company

Founders

Matthew Prince (CEO), Michelle Zatlyn (President), Lee Holloway

Customers

—

Isolation

V8 isolates + Cloudflare Containers (microVMs)

Cold start

~5 ms (Workers cold start)

GPU

—

Snapshots

—

Storage

Durable Objects + R2 + KV

Compliance

SOC 2, HIPAA, GDPR, ISO 27001, FedRAMP

GitHub

—

Last release

—

Edge

Edge sandbox spanning 320+ data centers; global reach by default.

CodeSandbox

Pending full review.

Founded

2017

Team size

—

Funding

—

Founders

Ives van Hoorne, Bas Buursma

Customers

—

Isolation

Firecracker-based microVMs

Cold start

—

GPU

No

Snapshots

Fork + snapshot

Storage

—

Compliance

SOC 2, GDPR

GitHub

—

Last release

—

Edge

Mature browser-IDE platform pivoting to programmatic sandbox SDK.

Vercel

Pending full review.

Founded

2015

Team size

—

Funding

—

Founders

Guillermo Rauch (CEO) — creator of Next.js, Socket.IO, Mongoose

Customers

—

Isolation

Firecracker microVMs

Cold start

—

GPU

—

Snapshots

—

Storage

—

Compliance

SOC 2, GDPR

GitHub

—

Last release

—

Edge

Sandbox primitive baked into Vercel's deployment platform.

Fly.io

Pending full review.

Founded

2017

Team size

—

Funding

—

Founders

Kurt Mackey (CEO)

Customers

—

Isolation

Firecracker microVMs

Cold start

—

GPU

Yes — GPU regions available

Snapshots

—

Storage

Volumes + LiteFS/Tigris

Compliance

SOC 2, GDPR

GitHub

—

Last release

—

Edge

Per-second microVM billing with 35+ global regions.

Browserbase

Pending full review.

Founded

2024

Team size

—

Funding

—

Founders

Paul Klein IV (CEO)

Customers

—

Isolation

Headless Chromium sandboxes

Cold start

—

GPU

No

Snapshots

Browser session checkpoint

Storage

Session persistence + recordings

Compliance

SOC 2

GitHub

—

Last release

—

Edge

Headless browser sandboxes purpose-built for agent web tasks.

Northflank

Pending full review.

Founded

2019

Team size

—

Funding

—

Founders

Will Stewart (CEO), Olu Niyi-Awosusi

Customers

—

Isolation

Kubernetes-managed containers

Cold start

—

GPU

Yes

Snapshots

—

Storage

Persistent volumes + managed databases

Compliance

SOC 2, HIPAA, GDPR

GitHub

—

Last release

—

Edge

Managed K8s + BYOC sandboxes for production-grade workloads.