/ Kiz8/ Tech review/ Sandbox

Sandbox.

/ Where agents run code.

Compute sandboxes for AI agents — microVMs, containers, and snapshot architectures that let agents run code, browse the web, and persist state without crashing each other or the host.

46 vendors·Last update 2026-05-18

/ sandboxes directory · 46 vendors

Every vendor,
on one page.

A working directory of 46 sandbox vendors — funding, founders, GitHub footprint, team size, and the one paragraph that captures what makes each of them tick. Curated from Crunchbase, GitHub, company blogs, and press releases.

Vendors

46

Open source

19/46

Free tier

26/46

YC-backed

14/46

/ By era

Sandbox launches surge after 2024

Pre-2020Legacy era
715%
2020–22Dev tools
1022%
2023–24AI agents
1226%
2025–26Sandbox boom
1737%

/ Team size

Most vendors are still tiny

Solo1–3
920%
Small4–10
1022%
Mid11–30
1226%
Large30+
1022%
Unknown
511%

/ Backing

YC dominates new entrants

YCY Combinator
1430%
VCPriced rounds
2146%
BootSelf-funded
511%
PublicNYSE/NASDAQ
12%
Unknown
511%
#VendorYearOSSFTYCGitHubTeamFundingNotes
012025~7 stars across all repos (computer-host: 2, computer-guest: 2, computer-nix: 3, torch: 3)1-2 (solo/small team based on GitHub activity; organization has no public members on GitHub)

Not found — no funding announcements found

Firecracker-based microVMs with ~400ms cold starts. Offers hosted cloud and open-source self-hosting. Flat $20/mo for up to 10 computers. Small team (1-2). YC-backed.

022021~1,500+ stars (beam-cloud/beta9)5-7 employees

$7M raised from Y Combinator, Tiger Global, Guy Podjarny (Snyk founder), Jason Warner (former CTO of GitHub)

Open-source beta9 runtime (gVisor/runc). GPU support (A10G, RTX 4090, H100). Billed by millisecond. $7M from YC, Tiger Global. ~5-7 employees.

032024Not found — partial open source (SDK/CLI available)6 co-founders + team (core team of ~6 employees as of early 2025)

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

Firecracker microVMs, sub-25ms standby resume. 16 global regions. GPU (T4, L4, A100). Usage-based with $200 free credits. $7.3M Seed. 6 co-founders.

042025Not found — CLI is @castari/cli on npm3 employees

Y Combinator (Fall 2025 batch); funding amount not disclosed

Built on E2B. 120s invocation limit. Free during beta. Forever-running sandboxes on roadmap. YC Fall 2025. 3 employees.

052009~500+ (cloudflare/sandbox-sdk)Cloudflare has ~3,000+ employees; Sandbox SDK is a product line within Containers team

Cloudflare is public (NET on NYSE); Sandbox SDK is product feature, not separately funded

Part of Cloudflare Workers. Containers with keepAlive. 300+ edge locations. Cloudflare is public (NYSE: NET, ~3,000 employees). Founded 2009.

062017~13,605 stars (codesandbox-client) + ~6,100 (sandpack) + ~107 (codesandbox-sdk); 6-month delta: ~+200 on client (~1.5%)~17 employees (2025, per GetLatka). Now part of Together AI (acquired December 2024).

~$15.1M total — Seed $2.4M (May 2019, Kleiner Perkins) + Series A $12.7M (Oct 2020, EQT Ventures). Acquired by Together AI (Dec 2024, undisclosed).

Firecracker microVMs with snapshot resume (500ms P95). Sandpack SDK. Acquired by Together AI (Dec 2024). ~$15.1M funding. 17 employees.

072023~50+ (cased/sandboxes repo)Small (appears to be 1-3 based on GitHub activity)

Not found

Provider-agnostic library (E2B, Modal, Daytona, Vercel). Free up to 2 users. Pro $499/mo. ~50 stars. Founded 2023.

082024~181 stars (computesdk org on GitHub)~1-5 (21 GitHub contributors, likely <5 full-time; Snelling LLC)

Likely bootstrapped/self-funded by Snelling, LLC (no external funding found)

Provider-agnostic SDK. Hobby: 1,000 sandboxes/mo free. Pro $500/mo. Bootstrapped. ~181 stars. Founded 2024.

092025~16,700+ stars (trycua/cua main repo), 3,240+ commits, 63+ contributors3-4 employees (YC says 3, PitchBook says 4).

$500K total — Early Stage VC round. Investors: 468 Capital, Orange Collective, Script Capital, Transpose Platform, Vento, Y Combinator.

Apple Virtualization Framework via Lume. macOS/Linux/Windows/Android. ~16,700 GitHub stars. 3-4 employees. $500K funding. YC.

102023~72,400 stars (+33,100 over 6 months, ~+84%). Forks: 5,600+. Contributors: 225.~20 people (Feb 2026). Hiring aggressively — 11+ open roles. Technical team in Croatia (Split/Zagreb), GTM in US.

$31M total — Pre-seed $2M (Nov 2023) + Seed $5M (Jun 2024, Upfront Ventures) + Series A $24M (Feb 2026, FirstMark Capital lead). Strategic: Datadog, Figma Ventures.

Linux containers, sub-90ms cold start. GPU support. Warm pool pre-provisioning. $31M funding. ~72,400 GitHub stars. ~20 employees. Founded 2023.

112024~70-100 total across 55 repos (top: nextjs-postgresql-template: 12 stars)4-6 employees (4 GitHub contributors visible)

EUR 255,000 Pre-seed (8 angels + Angel CoFund via FIBAN)

Kubernetes-based dev/staging/prod. Always-hot, no cold starts. EUR 255K Pre-seed. 4-6 employees. Founded 2024.

122022~190+ stars (depot/cli main repo), 85+ repos in depot org~14-15 people (14 profiles visible on about page)

$14.1M total — $4.1M Seed (Aug 2024, Felicis) + $10M Series A (Mar 2026, Felicis). YC W23.

Docker CI + agent sandboxes. Standby pool of EC2 instances. Ceph-based NVMe cache. $14.1M funding. YC W23. ~14-15 employees.

132023~12,200 stars (e2b-dev/e2b, +2,800 over 6 months); e2b-dev/desktop: ~1,400. Total ecosystem: ~13,600+~18 employees (May 2026). Distributed: 8 US, 7 Czech Republic, 3 other.

$32M total — Pre-seed ~$3M (Kaya VC) + Seed $11.5M (Oct 2024, Decibel Partners) + Series A $21M (July 2025, Insight Partners lead)

Firecracker microVMs, 150ms p50 creation. 12,200 GitHub stars. $32M funding. 18 employees. Founded 2023. 88% of Fortune 100 are customers.

142024Not open-source (exeuntu Dockerfile is OSS; main code closed)~5-10 employees (3 named founders + several team members)

$35M Series A (Apr 2026, led by Amplify Partners, with CRV + HeavyBit)

KVM-based persistent VMs. crosvm-derived VMM. 9 regions. $35M Series A. 5-10 employees. Founded 2024.

152025722 stars (+ growth from recent project, first commit ~Dec 2025)Not found (GitHub shows 14 contributors)

Not found (open-source project under Apache 2.0, no public funding disclosed)

OS-level sandbox (sandbox-exec/bubblewrap/Landlock). Zero latency. Apache 2.0. 722 stars. By Use-Tusk (YC W24).

162025Not found (Hopx SDK is pip-installable, closed-source)Part of Bunnyshell (~24 employees total); no separate Hopx team

Parent Bunnyshell raised $10.2M total (latest: €4M late seed in 2023)

Firecracker by Bunnyshell team. ~100ms cold starts. Pay-per-use. Bunnyshell raised $10.2M. Founded 2025.

172024sandbox_sdks: 8, Adorable: 740, cloudstate: 210 (main product repos)5 employees

YC funding (amount not disclosed)

KVM VMs, <700ms cold start. Landlock sandboxing. ~$500K YC S24. ~5 employees. $1M ARR. Founded 2024.

182026~14 stars total (docs: 11, index: 3)3 employees

YC P26 funding (amount not disclosed)

AMD EPYC Zen 5 with VM snapshot forking. ~26ms spin-up. YC P26. ~3 employees. Founded 2026.

192025coderunner: 824 stars; clickclickclick: 694 stars; open-skills: 408 stars; total org: ~1,900+ stars across reposNot publicly disclosed (GitHub org has no public members; no About/Team page; Microsoft/GitHub Open Source sponsorship)

Microsoft and GitHub Open Source sponsorship (amount not disclosed)

Firecracker, sub-200ms. Free + Pro $100/mo. ~1,900 GitHub stars. Microsoft/GitHub sponsorship. Founded 2025.

2020164.2k stars (judge0/judge0 repo)1 (sole founder Herman Zvonimir Došilović)

Self-funded / bootstrapped (donations via Patreon/PayPal); no VC funding found

Isolate + Docker, 60+ languages. GPL-3.0. 4.2k stars. Bootstrapped. Founded 2016.

212021~473 stars (modal-labs/modal-client)~79 employees (offices in NYC, SF, Stockholm; Sep 2025 data)

~$110M total; Series B $87M (Sep 2025) at $1.1B valuation led by Lux Capital; Series A $16M (Oct 2023); Seed $7M (Dec 2021). In talks for new round at ~$2.5B valuation as of Feb 2026

gVisor, ~1s boot. GPU T4 to B200. $110M+ at $1.1B valuation. Founded 2021.

222020~138 stars across main repos (koyeb-cli: 71, kreconciler: 48, control-panel: 15)Fewer than 25 employees (at time of funding); 11-50 range

$16.0M total across 3 rounds; latest $7M venture round November 2023; acquired by Mistral AI February 17, 2026

Serverless containers. Acquired by Mistral AI (Feb 2026). $16M total. Founded 2020.

232024~6,000 stars (+~2,700 over 6 months; was ~3,300 at May 2025 launch)Not found (small team; YC X26 batch)

Y Combinator (X26 batch), no publicly announced funding round beyond YC

libkrun MicroVM. 6,000+ stars. YC X26. Founded 2024.

242021~459 stars total across 49 repos (foundation: 152, breakpoint: 307)~20 employees

$23M (Seed + Series A led by NEA, Susa Ventures, burst.vc — March 2026)

microVM dedicated kernel. 0.8s start. $23M (NEA, Susa). ~20 employees. Founded 2021.

252025~2,300 stars (+ rapid growth since Feb 2026 launch)1 (primarily Luke Hinds, 59 total contributors on GitHub)

Not found (open-source project, not a funded company)

Landlock + Seatbelt. 2,300+ stars. By Luke Hinds (Sigstore creator). Open source. Founded 2025.

262019~14 stars (original repos; org has high-star forks). Closed-source platform.29 employees (PitchBook); 19 per GetLatka (2025 data may vary)

$30.8M total raised; Series A $22.5M (Nov 2024) led by Bain Capital Ventures; earlier Seed $6.3M led by Vertex Ventures US; Accelerator/Incubator in 2019

Firecracker/Kata/gVisor. 256MB-256GB. $30.8M (Bain Capital). 29 employees. Founded 2019.

27202610,500+ stars (+ rapid growth; hit 3,845 stars within 72 hours of release in March 2026)64 contributors on GitHub

Not applicable (open-source project by Alibaba Cloud, not a separate funded entity)

Alibaba open-source. gVisor/Kata/runc. 10,500+ stars. Apache 2.0. Founded 2026.

28202450+ (runloopai/runloop-examples)Nov-50

$7M seed (July 2025) led by The General Partnership, Blank Ventures

Isolated ephemeral VMs + container layer. <2s boot. $7M seed. Founded 2024.

292025~178 stars (+14 forks)7 contributors on GitHub

Not found — created by Digger team (Digger had ~4,900 GitHub stars as infrastructure tool)

KVM VMs with hibernate/wake. ~300ms resume. ~178 stars. By Digger team. Founded 2025.

3020222,900+ (rivet-dev/agent-os)5 (YC profile, 2023)

Y Combinator W22 batch (~$500K); Amounts not publicly disclosed

WebAssembly V8 isolates. ~6.1ms cold start. YC W22. Founded 2022.

312026116 (runtm-ai/runtm)Not found (4 GitHub contributors)

Not found (open source project, no announced funding)

OS-level sandbox + Docker deploy. 2-3 min first deploy. YC W26. Founded 2026.

322026N/A (part of Fly.io; SDKs: superfly/sprites-js, superfly/sprites-go)Part of Fly.io (~70 employees)

Fly.io has raised ~$87M total; Sprites is a product line, not separately funded

libkrun MicroVM. <200ms boot. Apache 2.0. Part of Fly.io (~70 employees, ~$87M). Founded 2026.

332022~817 stars on tensorlakeai/tensorlake repo~10 employees (PitchBook estimate)

$8M Seed (per StartupHub.ai)

WebAssembly via Wasmer. <5ms restore. $8M Seed. ~10 employees. Founded 2022.

342020Not applicable (Box is a managed service, not open-source)Not explicitly stated; co-founders are Enes Akar, Mehmet Dogan, and Bilal Yasar

$12M total across 2 rounds; $10M Series A led by a16z (Andreessen Horowitz) in February 2024

Firecracker. 150ms startup. $12M (a16z). Acquired Upstash. Founded 2020.

352025N/A — Fly.io product, no separate open-source org. SDK repos: sprites-js, sprites-go, sprites-py (part of superfly)~60 employees (Fly.io overall; Sprites is a product line)

$87M total raised by Fly.io (latest $25M extension, 2024)

Firecracker via Fly.io. <1s cold start. Per-second billing. Part of Fly.io. Founded 2025.

36201776.7k+ GitHub stars on StackBlitz (per website)~20 people (as of January 2025)

$135M total; $105.5M Series B led by Emergence Capital and GV at $700M valuation (January 2025)

Docker containers. Auto-pause after 30 min. Developer Preview. By Upstash (acquired by Tensorlake).

37202116,449 stars (per ossinsight, 2026)18 employees (per GetLatka, 2024)

$15M across 2 rounds; $5M Series A in October 2024 (led by YETI Capital, Pentland Ventures)

Firecracker on Amazon Linux 2023. Sub-second cold start. Part of Vercel ($1.5B+ valuation).

382017MCP server repo: yepcode/mcp-server-js (stars not checked)~20 employees (PitchBook 2025; grew from ~15 after Bolt.new success)

$135M total — Seed $7.9M (Apr 2022) + Series A $22M (Nov 2024) + Series B $105.5M (Jan 2025) at $700M valuation (Emergence Capital, GV)

Browser WASM. ~5s boot. Client-side only. 76.7k+ GitHub stars. $135M at $700M valuation. Founded 2017.

392022~16,470 stars (+2,000 over 6 months; was ~14,400 in Nov 2025)10-18 employees (team of 10 engineers per job posting; based in Paris, France)

Bootstrapped/profitable; $3M ARR, 300+ enterprise customers; YC S22 batch (~$500K); no priced VC rounds disclosed

NSJAIL + persistent volumes. ~50ms orchestration. 16,470 GitHub stars. Bootstrapped. AI Sandboxes: Apr 2026. Founded 2022.

402023langchain-ai/langchain-sandbox: 239 stars as of May 2026 (repo created 2025-04-15; 6-month delta not publicly tracked)~163 employees (as of late 2025/early 2026)

~$260M total; last round Series B $125M at $1.25B valuation led by IVP, Oct 20, 2025 (preceded by $100M Series B in Jul 2025 at $1.1B; $25M Series A from Sequoia Feb 2024; $10M seed from Benchmark Apr 2023)

HW-virtualized microVMs. Warm pools for zero cold starts. NVIDIA GPU partnership (Mar 2026). ~163 employees. $160-260M. Founded 2023.

412018106,675 stars (denoland/deno, 2026-05-14); 6-mo delta not measured~42 employees (Tracxn); 17 reported July 2022

~$30.9M total; last round $21M Series A (Jun 2022, led by Sequoia)

Firecracker. 30-min max. CPU only (2 vCPU). Sub-second cold start. $21M Series A. Founded 2018.

422025266 stars (repo created 2025-10-10, ~7 months)2-10 employees — small globally distributed team based in San Francisco; 1 open position; 10 GitHub repos; 274 stars

$2M initial via OCV (Open Core Ventures) in November 2025; originally launched as RayAI; founder: Pavitra Bhalla (ex-LTSE, ex-Dosu)

Firecracker. <200ms cold start. No GPU. CIDR+domain policies. $2M OCV. 2-10 employees. Founded 2025.

432026superhq: 246 stars, 16 forks; shuru: 739 stars, 23 forks~2-3 people (Harsh Singh + Dhruv Saxena + Mark Fredrickson)

Not found — appears bootstrapped/indie (no VC backing found on Crunchbase)

Local-first macOS app using Apple Virtualization.framework. Real VM isolation (not Docker/worktrees). Keyboard-driven workflow. Two repos: superhq (AGPL-3.0, 246 stars) and shuru (Apache-2.0/MIT, 739 stars). YC-connected founder (FifthTry YC W21). 97 Product Hunt upvotes. Windows port in progress.

442026~6 stars (anyframe-python SDK on github.com/tinyhq)~2-3 (very early stage; 2 known founders; Nishchith works FT at Atlan)

Not found — no Crunchbase profile; likely bootstrapped

Very early stage (Feb 2026 launch). Founder Nishchith Shetty works full-time at Atlan. Tiny HQ is legal entity. No public pricing page. Supports Claude Code, Codex CLI, Cursor. Core differentiator: pausable microVM sandboxes where agents snapshot-pause and resume hours/days later with full state. ~6 GitHub stars on SDK.

452024~113 stars (ZenithDB, Apache 2.0)~3-5 employees (hiring founding engineers)

Not found — appears bootstrapped/stealth (no funding data found on Crunchbase)

Polarity offers two products: Keystone (sandboxed eval infrastructure for AI agents) and Paragon (AI QA Engineer for code review at app.paragon.run). Firecracker-based with Docker fallback. SOC 2 Type II, GDPR, HIPAA, ISO 27001 compliant. Open-sourced ZenithDB (113 stars). ~3-5 person team.

462026~5 stars (pandastack-io/pandaflow, MIT license)~1-3 employees (solo founder + small team)

Not found — likely bootstrapped/self-funded (no Crunchbase entry)

Sandflare is a Firecracker microVM-based sandbox for AI agents by PandastackIO Inc. (Gurugram, India). ~300ms cold start via userfaultfd (UFFD) snapshot/restore. Key features: Agent Forking (split sandbox into N parallel VMs), full VM pause/resume, per-second billing. Founded by Ajay Kumar (ex-PhonePe, ex-Flipkart). Launch post on HN (Mar 31, 2026) and technical deep-dive on dev.to. Closed-source platform with open-source PandaFlow workflow builder (5 stars).

/ ● yes · ○ no · — unknown / pending · scroll horizontally for full columns · sticky vendor column · last updated May 2026

Active tab: Sandboxes data