Dan Chiarlone

Software Engineer for @Microsoft @Azure Micro-Compute team working with Wasm and Rust 🕸🦀 · Author of Server-side WebAssembly · Star Trek and SSBU fan

[Dan Chiarlone @danologue]

During the last year and a half, I wrote a book on server-side WebAssembly. Getting into Wasm is hard. Resources are scattered, the tech is complex, and it's constantly changing. I wanted to contribute a resource to make learning easier. https://t.co/NYqIvgcLf0 (1/5) 🧵

[2logics @2logics]

Microsoft (@Microsoft) engineer Danilo Chiarlone detailed on Monday how Hyperlight, a CNCF (@CloudNativeFdn) Sandbox project, runs unmodified Linux programs inside hypervisor-isolated micro-VMs through its newest component, hyperlight-unikraft.

Key details:
What it is: Hyperlight is a library VMM with a Rust core that apps link in, unlike separate processes such as QEMU or Firecracker
No porting: hyperlight-unikraft boots a Unikraft unikernel and runs the same Linux binaries, with no SDK, special libc or recompiling
Runtimes: Python, Node.js, .NET, Java, PHP, Go, Rust, C, Bash and PowerShell, on x86_64 and arm64
Snapshots: the guest is saved once its runtime is warm and restored in a few milliseconds
Benchmarks: a Python script importing numpy, pandas and scikit-learn took 45 ms from snapshot vs 1,119 ms natively, while a Python hello world was slower (22 ms vs 17 ms)
Locked down: the guest gets no network or host files unless the embedding app grants them
Integrations: urunc for containerd and Kubernetes, smolagents, an MCP server, ClickHouse Python UDFs, verl training and the OpenAI Agents SDK
Demo: an exploit for a since-fixed Wasmtime bug that read host secrets could only reach the micro-VM’s own memory inside the sandbox

Why it matters: More software now runs code nobody on the team wrote, from AI agent output to customer plugins. VM-level isolation that starts in milliseconds makes it much easier to keep that code away from the host.

Sources: CNCF blog, Nov. 9, 2026. Image: CNCF.
#CloudNative #Security

[Dan Chiarlone @danologue]

My blog post on Hyperlight just went live on the CNCF blog!!

It shows how you can run unmodified Linux apps in hypervisor-isolated micro-VMs that start from a warm snapshot. See image for more details!

- Blog post: https://t.co/eCRXFtOskb
- Repo: https://t.co/pCDRoOULA3

[ACM Education & Learning Center @acmeducation]

Now available for ACM Members: "Server-Side WebAssembly: Building Portable and Secure Multi-language Apps," by @danologue. Foreword by @brendandburns. Afterword by Luke Wagner. You'll learn how to develop/deploy erver-side #Wasm apps; create/manage Wasm...
https://t.co/C4YcWAobzi

[David Justice @davidjustice]

🚀 Azure Front Door edge actions is live in public preview powered by Hyperlight, the isolation engine my team builds! Every customer's code runs in its own Hyperlight VM. Secure, programmable compute at the global edge. So proud! 🛡️🔥 #Azure #Hyperlight https://t.co/tjf8Qxq1N1

[zalim (kotlin wasm compiler webassembly VM) @bashorov]

"Server-side WebAssembly" — kindly gifted and signed by @danologue at #WasmCon26 🙏

https://t.co/Aheh2Y7Lqv

#WebAssembly #Wasm #WasmCon

[Manning Publications @ManningBooks]

Can you combine Wasm sandboxing with hardware isolation and still avoid slow cold starts?

@danologue breaks down two approaches:
• No OS (just memory and CPU)
• Microkernel (controlled syscalls and more support)

Catch him March 23rd at 10:40am CET: https://t.co/uVX673e7x9

45% off his book with code KubeConEU26: https://t.co/c1j44jxg2Q

[Dan Chiarlone @danologue]

I've been working on making it easier to run higher-level apps (e.g., Python) in #Hyperlight by adding POSIX support to our micro-VMs. Posted about it on MSFT's OSS blog (see below). It features a demo w/ Hyperlight micro-VMs running AI generated code :)
https://t.co/MvId16FbGI

[RustConf @rustconf]

🎤 The RustConf 2026 CFP is OPEN!

We’re looking for talks that share real experiences using Rust — what you’re building, what you’ve learned, and what’s working in practice.

Submit your proposal by February 16: https://t.co/DjRbP4Q6iA #rustconf #rustconf25

[Dan Chiarlone @danologue]

Anyway, I'm really proud to be able to hold a book I've written myself, so figured I'd share. Big thanks to the team at @ManningBooks, everyone who reviewed the book, Brendan Burns for the foreword, and Luke Wagner for the afterword. (5/5) 🧵

[Dan Chiarlone @danologue]

During the last year and a half, I wrote a book on server-side WebAssembly. Getting into Wasm is hard. Resources are scattered, the tech is complex, and it's constantly changing. I wanted to contribute a resource to make learning easier. https://t.co/NYqIvgcLf0 (1/5) 🧵

[Dan Chiarlone @danologue]

I also took inspiration from one of my favourite technical books, Accelerated C++ by Andrew Koenig and Barbara E. Moo. Like that book, you'll apply what you learn to a running project (a smart content management system) at the end of every chapter. (4/5) 🧵

[Manning Publications @ManningBooks]

WebAssembly isn't just for the frontend.

Server-Side WebAssembly by @danologue shows how to use components, WASI, and backend architecture together to build real web back ends — anchored by a practical CMS project

Now in print. 50% off through Jan 12th: https://t.co/5ENhtcipjz

[Manning Publications @ManningBooks]

📣 Deal of the Day 📣 Jan 3

Now in print! HALF OFF today!

Server-Side WebAssembly: Building portable and secure multi-language apps & selected titles: https://t.co/SGJjjc1z1S

"WebAssembly on the server is the future of computing."
- Solomon Hykes, founder of Docker

This book lays out everything you need to take #WebAssembly beyond its traditional browser domain. By following the numerous practical examples and crystal-clear explanations, you'll soon be seeing the benefits of reduced cold start times, improved security and performance, and the freedom of polyglot programming. @danologue #wasm #rustlang #rust

[Manning Publications @ManningBooks]

Tired of trading performance for safety? Or portability for speed?

WebAssembly challenges that tradeoff. Server-Side WebAssembly by @danologue shows how to use it in real systems.

Now in print! 50% off with code chiarlonePB through Dec 31st: https://t.co/gtoVhrvxxs

[Jonathan Gennick @JonathanGennick]

Another book gone to print this week. I like the assembly angle. Early in my career I wrote a fair bit of 6502 assembly, 8086 assembly, and even quite a bit of Xerox Sigma VI assembly. Those were good days, and I enjoyed dropping into assembly from the various higher level languages I was coding in. Sometimes my doing that was justified, and other times I really shouldn't have. We grow in wisdom (hopefully!) as we progress in life.

#wasm #webassembly #assembly @danologue @ManningBooks

https://t.co/10fLZn4gKO

[Manning Publications @ManningBooks]

Kubernetes shouldn’t have to choose between speed & safety.

See how Hyperlight and Nanvix combine container-level performance with VM-level isolation.

Watch @danologue’s live demo at @rejektsio (15:10 EST): https://t.co/mmEXkVCGvJ

Check out Dan's book in our KubeCon bundle: https://t.co/jJQzm65LGz

[Dan Chiarlone @danologue]

Proposal submissions for WasmCon EU close Sunday, November 2nd! The conference is March 26th in Amsterdam. Submit your talk today if you'd like to present!

https://t.co/7QX1rdHmXp
https://t.co/7QX1rdHmXp

[Manning Publications @ManningBooks]

Rust is fast & efficient. But how do you bring an existing codebase up to that level?

Today 3:45 PT at #RustConf: @d@danologue (author of Server-Side WebAssembly) & Ludvig Liljenberg share how they re-engineered Microsoft’s Hyperlight in Rust.

→ Register: https://t.co/xplqJY3pDM
→ Book 45% off (code: RustConf25): https://t.co/mrEHFdqWgw