Blog — page 15 of 38
How to deploy a remote MCP server
Your MCP server works over stdio. Making it remote is four changes, and three of them fail silently — a buffered stream, a lost session, and an auth layer in front of the discovery path.
How to give a Mastra agent a code execution tool
Mastra makes defining a tool trivial, which is exactly why the code-execution one goes wrong. The hard parts are where the code runs, what happens on timeout, and how you hand results back without blowing the context window.
How to handle file uploads in a deployed app
Every upload feature starts by writing to ./uploads and works perfectly until the first redeploy, when the files are gone. Here is the version that survives, including the part where the file is a zip bomb.
How to write a health check that catches real failures
Almost every health check is a route that returns 200 OK. It proves the process is running, which was never in doubt, and it will happily report health while every request fails.
The best Java and Spring Boot hosting platforms in 2026
The JVM does not behave like the runtimes most platforms were designed around. It wants a big chunk of memory it can keep, several seconds to warm up, and a process that stays alive. Pick a host that offers all three.
The best Remix and React Router hosting platforms in 2026
Remix is the framework where the hosting decision cannot be deferred. There is no static export to fall back on: every page view runs your loader on a server somewhere, and which server that is shapes everything else.
The best load testing platforms in 2026
The hard part of load testing was never generating requests. It is generating them from enough machines, without saturating the generator, and reading a percentile that means what you think it means.
The best Selenium Grid alternatives in 2026
Nobody replaces Selenium Grid because of the protocol. They replace it because a long-lived browser node accumulates state, and a flaky test is indistinguishable from a poisoned node.
The best CodeSandbox alternatives in 2026
Half the people looking for a CodeSandbox alternative want an embeddable editor for their docs. The other half want an API that gives an agent a machine. Those are different products, and mixing them up is why the shortlists never help.
The best Supabase Edge Functions alternatives in 2026
Almost nobody leaves Supabase Edge Functions because of Deno. They leave because the function is at the edge and the database is not, or because the work takes longer than a function is allowed to live.
The best Prisma Postgres alternatives in 2026
Prisma Postgres is convenient precisely because it is bundled. The bundle is also the thing you eventually want to take apart — and you can keep the ORM while replacing everything under it.
How to branch a Postgres database for a pull request
A shared staging database is the reason your migration reviews are guesswork. Give each pull request its own copy of production-shaped data and the review becomes a fact.
How to upload and download files from a sandbox
Writing a file into a sandbox is one call. Getting a 300 MB model artifact back out is a different problem, and the API that handles the first one is the wrong tool for the second.
How to run Playwright tests in a sandbox
Playwright is fast until you run it on a shared CI runner, where eight workers fight over one page cache and a 64 MB /dev/shm. Give each shard its own machine and the flake profile changes.
A Checkpoint Is a Program: Isolating Untrusted Model Weights
You downloaded a checkpoint from a model hub and called torch.load. Congratulations: you ran a stranger's Python as yourself. Here's the threat model, and the disposable-microVM ingest pipeline that turns hostile weights into boring data.
Running Per-Tenant Blockchain RPC Nodes in MicroVMs
A synced chain node is a stateful, disk-hungry, P2P-chatty pet — and everyone tries to run one of them behind an API gateway for a thousand customers. Here's why that shape breaks, why a microVM per tenant fits, and the honest part: snapshots make provisioning cheap, but they don't make terabytes of archive state free.
Per-Room WebRTC Media Servers in MicroVMs
One hot room with recording on can starve every other call on the box. Here's what a microVM per room buys an SFU — and an honest accounting of the UDP, NAT, and ICE work it costs you.
Guest kernel lockdown and module loading in Firecracker microVMs
Root in the guest is not a breach, it is Tuesday. But what root can then do to that kernel is the first half of every escape chain — and in a snapshot-restore world, the hardening has to be baked in, because nothing runs at boot ever again.
fsfreeze and the Three Tiers of Snapshot Consistency
Copying a live disk gives you a crash-consistent image — a polite way of saying you pulled the power cord and hope the journal is forgiving. Here's the ladder from there to application-consistent, and the fsfreeze mechanics that get you up a rung.
IPv6 for Firecracker MicroVM Fleets
Every microVM networking guide is IPv4, TAP, NAT, a /30 per guest. That works until you run out of address space — or until someone notices your carefully written egress allowlist only speaks one address family. Here's the IPv6 version, including the parts snapshots make awkward.
The best Rust hosting platforms in 2026
Hosting a Rust service is backwards from every other language: the artifact is the easiest thing in the world to run, and getting to it can take eight minutes and more RAM than your builder has. Evaluate the build machine first.
The best .NET and ASP.NET Core hosting platforms in 2026
.NET left Windows behind years ago, but a lot of hosting advice never got the memo. The decisions that actually matter now are your publish model, JIT warmup, the GC's appetite in a memory-capped box, and whether your platform tolerates a WebSocket that lives for an hour.
The best MongoDB Atlas alternatives in 2026
Half the people shopping for a MongoDB Atlas alternative want another document database. The other half want Postgres and have not admitted it yet. Sorting out which half you are in is the whole exercise.
Cloudflare Sandbox SDK vs E2B for Agent Code
Cloudflare's Sandbox SDK binds code execution to Workers and Durable Objects. E2B is a standalone sandbox API you can call from anywhere. Same shortlist, genuinely different bets — here's how to tell which one your architecture wants.