Modal closed a $750M Series D led by Accel at a $15.75B post-money valuation, 3.4x its $4.65B Series C in May. The signal: isolated environments where agents run the code they write have gone from an add-on to a standalone $300M-a-year business.
The cloud deep dive post (order 12) of the Sandbox Series. Modal Sandboxes architecture, GPU sandbox support, pricing model, and how it grew from a feature to a $300M–$1B annualized run rate standalone product line.
The business post (order 27) of the Sandbox Series. How Modal's sandbox grew from a feature to a $300M–$1B annualized run rate standalone product line, pricing and packaging strategies, and implications for build-vs-buy decisions.
The cloud landscape post (order 7) of the Sandbox Series. Summarizes positioning, pricing, cold start, isolation strength, and applicable scenarios for E2B, Daytona, Runloop, Vercel, Cloudflare, Modal, AWS Bedrock AgentCore, Alibaba OpenSandbox, Azure Container Apps — with a selection decision matrix.
Modal is a per-second-billed serverless GPU platform that also treats agent sandboxes as a first-class primitive (company-reported: over 1 billion sandboxes launched, more than a third of revenue). The selection question isn't how convenient it is — it's your GPU utilization. Verified 2026-08-21: Modal's A100 80GB works out to $2.50/hr against RunPod's $1.59/hr for the same card, so above 64% utilization renting your own is cheaper. But on the same day, H100 SXM is $3.95/hr on Modal against $3.99 on Lambda — on that card the premium is gone.
Hermes can run commands on seven backends: local, ssh, docker, singularity, modal, daytona, and vercel_sandbox. The decisive trade-off isn't performance, it's approval — local and ssh run dangerous-command checks, the other five skip them entirely because the container is treated as the boundary. Also, Docker defaults to one long-lived container shared across sessions, not a fresh environment per conversation.
For side projects, toy demos, and RAG prototypes, nobody wants to swipe a credit card on day one. This is a verified roundup of 40+ LLM inference providers still operating as of 2026/05, tiered by whether free resources auto-replenish or are one-time grants. Each entry notes credit-card requirements, supported models, paid starting prices, and catches. Chinese-origin providers including Zhipu GLM (permanently free), Doubao (2M tokens/day), Kimi, DashScope, and the Ollama local option are all included.