Blog — page 32 of 38
Sandboxing AI-Generated Terraform and Infrastructure-as-Code
An agent that writes Terraform and runs `terraform apply` can delete your prod database or exfiltrate your cloud keys — IaC tooling executes arbitrary providers and reads the environment. Run `plan` in a disposable microVM, gate `apply` behind a human review of the diff.
Running Long-Lived AI Agent Tasks in microVMs Without Paying for Idle
A deep-research or coding agent runs for minutes to hours but spends most of that wall-clock waiting on a token stream. Give it one durable sandbox that survives every step — and hibernate it while it thinks so you're not renting a hot CPU to do nothing.
Per-Tenant Email Sending Isolation with microVMs
Your customers write email templates and send-time transforms. Running that in your shared worker is how one tenant's infinite Handlebars loop melts everyone's Tuesday. Give each send its own microVM.
Running AI Agent Eval Harnesses in Isolated microVMs
Every eval task needs a clean, reproducible box the agent can trash. Bake the task environment once, fork per attempt, run hundreds in parallel, and never let task 7 poison task 8.
Running Customer UDFs Safely in a SaaS with microVMs
The moment your product lets a customer write code — a workflow step, a validation hook, a transform — you're hosting untrusted code in your infra. Here's how to run it without betting the company on it.
Testing LLM-Generated Database Migrations Safely in a Sandbox
An AI agent writing a migration is one hallucinated DROP TABLE away from ruining your night. Apply it to a disposable Postgres VM first, diff the schema, and throw the VM away.
Building an Online Judge on microVMs
Contestants submit fork bombs, /proc snoopers, and code that tries to read the answer key. A microVM-per-submission judge makes that their problem, not your host's.
How Firecracker Schedules vCPUs: The Threading Model
A Firecracker vCPU is just a host thread wearing a convincing hat. Here's how those threads map to physical cores, how Linux CFS schedules them, and why you can pack far more vCPUs than cores.
Debugging a Firecracker microVM That Won't Boot
A microVM that boots to a silent black hole is Firecracker's way of saying you assumed the rootfs, didn't you. Turn on the serial console and let the kernel tell you what actually went wrong.
PandaStack vs Beam Cloud: which for AI code?
Beam Cloud is a serverless GPU/Python cloud for workloads you own; PandaStack runs untrusted agent code in per-task Firecracker microVMs. An honest comparison.
The Zygote Pattern: Fork One Warm Snapshot Into Thousands of MicroVMs
Bake one microVM with the heavy framework already imported, then fork it a thousand times. The children share the parent's pages copy-on-write, so N VMs cost far less than N× the RAM.
Multi-Tenant Notebooks: microVM Sandboxes vs JupyterHub
JupyterHub is a great auth + proxy + spawner framework — but its isolation is only as strong as the spawner you pick. Here's where a microVM-per-user changes the math, and where it doesn't.
Sandboxing an AI Email-Triage Agent
An email-triage agent opens attachments, follows links, and does whatever the message body tells it to. Detonate each email in its own throwaway microVM, then delete it.
Running User-Uploaded Automation Scripts Safely
The moment your SaaS lets users write a "run this Python" step, you're running arbitrary strangers' code on your servers. Here's how to give each uploaded script its own throwaway microVM instead of a shared worker.
Per-Tenant Isolation for RAG and Vector Search
The scariest bug in multi-tenant RAG is the one where tenant A's question retrieves tenant B's board deck. Here's why a shared index makes it inevitable, and how a per-tenant microVM plus a dedicated pgvector database turns the tenant boundary into hardware instead of an if-statement.
Firecracker vs Microsoft Hyperlight, honestly compared
Hyperlight throws away the guest kernel to hit sub-millisecond starts for tiny WASM functions; Firecracker keeps a whole Linux guest so it can run anything. Same KVM lineage, opposite bets. Here's the fair comparison.
Firecracker Snapshot/Restore vs CRIU Checkpoint/Restore
CRIU freezes a process tree — FDs, sockets, memory — back onto a shared host kernel. Firecracker freezes the whole microVM — guest kernel included — and just doesn't tell the guest anything happened. Same idea, different layer, very different gotchas.
The Serverless Cold-Start Problem, Explained
A cold start isn't one thing — it's a stack of them: provision a sandbox, init a runtime, load dependencies, run app init, wire up the network. This is where the milliseconds actually go, a taxonomy of the standard fixes and what each one really costs, and why snapshot-restore beats warm pools economically — plus the gotchas nobody warns you about.
WASM vs gVisor vs microVM for Untrusted Code
Three dominant ways to run untrusted or AI-generated code, on three different boundaries: a capability-sandboxed wasm module, a user-space kernel intercepting syscalls, and a real hardware-virtualized guest. Here's which one fits which workload, honestly.
Build vs Buy: Rolling Your Own Firecracker Sandbox
Firecracker is a 200MB binary that boots a VM. The other 18 months of work is everything around it. Here's an honest teardown of what building a real sandbox platform costs — and where the buy line actually is.
Isolating Real-Time AI Voice Agents Per Call
A phone bot that can look up an account, run a tool, or transfer funds is executing untrusted intent in real time — one live session per call. Give each call its own ephemeral microVM, scoped to that caller, torn down when they hang up.
Building a Minimal Firecracker Guest Kernel
Firecracker boots an uncompressed vmlinux with a deliberately tiny config. Strip the drivers, filesystems, and subsystems a microVM never sees; keep virtio, the console, and the KVM guest bits. Here's the config, the boot args, and why the kernel is pinned into every snapshot.
Run AI-Agent-Built Data Pipelines in Isolated microVMs
An AI agent writes the ETL, then runs it against your real API keys and warehouse. Give each pipeline run its own throwaway microVM — scoped creds in, artifacts out, blast radius of one.
Per-Customer Cron Jobs with microVM Isolation
One customer's runaway cron shouldn't be able to page your whole on-call. Here's how to run every tenant's scheduled job in its own throwaway microVM.