12 years at Apple. Now building apps for a million people. Getting to 10% body fat. New on the App Store: SayRay 👉 https://xitter.cf/t.co/YkfXIH9sJC
Bay Area 🤙🏽 Hawaii
Joined August 2023
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I was part of a secret project at Apple that revolutionized the way we update our devices, and it all started with a prototype that had no recovery port.
I was sitting in my office, when suddenly, I got pulled into this top-secret project. I mean, it was so hush-hush that I had to sign all these NDAs, and basically kiss my holidays and free time goodbye until we finished it.
So, I show up to the meeting, and the manager confirms I signed the NDAs. Then, he pulls off this black cloth, and boom! There's the prototype, right in front of me. My eyes were so big, and my heart was pounding like crazy. I had a million questions running through my mind.
Turns out, I was going to be the one making sure the Apple Watch could update without any problems.
But get this - when I asked about plugging it into a computer to recover it if something went wrong, the manager dropped a bombshell on me. There was no port! I was like, "HOLY CRAP! What did I just sign up for??" And then, he just walked away and told me to figure it out. Can you believe that?
I ended up spending the next several years working with tons of teams across Apple, trying to come up with a solution.
It was intense, but we managed to create this incredible update system that would totally change the game not only for the Apple Watch but for all future systems as well.
Looking back, it was one of the craziest and most challenging things I've ever done.
It taught me a lot about what I'm capable of and how important it is to have a great team by your side.
It also taught me how important developing relationships with people are. Always have people’s back no matter what and be a great human being. It returns dividends for life.
Stay Hungry. Stay Foolish.
Ray Fernando retweeted
Security Update for anyone running @NousResearch hermes, you need to recomplie your binary not just patch your ststem. (eMudhra)
We found hermes kept trusting the compromised chain anyway. The reason was in its Cargo.lock: webpki-roots 1.0.7 — Mozilla's root program compiled INTO the binary. It never reads /etc/ssl/certs. Patching the box does nothing for a binary that brought its own trust store.
What to do — today:
Inventory every agent or binary that ships its own TLS. Rust: check Cargo.lock for webpki-roots (fix: 1.0.10) and rustls-webpki (fix: 0.103.16). Node/Bun/Deno: the store is compiled in — rebuild on 22.23.4 / 24.22.1 / 26.12.1 (Node 20 never gets a fix; NODE_OPTIONS=--use-openssl-ca is the stopgap).
Rebuild and redeploy. Restarting an old binary changes nothing.
Still exposed? Stop the agent units and verify zero residual processes before assuming you're safe.
Verify with a probe, not a grep: the disclosure site's test hosts return HTTP 200 through the compromised chain — 200 = vulnerable, an explicit "issuer not in trust store" = safe. Test BOTH roots (emSign G3 and the AAA cross-sign), or your check false-passes.
Disclosure: emudhra.we-have-a-problem.co…
Proof-Driven Development is going to be a massive thing. Like enough to re-think what code review is/does in an agentic world.
I've never trusted code I didn't review until now.
Agents write more code than any of us can review. We often end up skimming the PR/diff and pushing. Current review methods do not prove the code is correct or does what we asked. Recent research found the best AI code reviewer caught the bug on its first try only 42% of the time.*
The evaluation bottleneck, regressions, and security incidents have forced us to find a better way.
Introducing Proof-Driven Development Kit (PDD Kit) from @MSFTResearch. PDD Kit brings assurance to AI-generated code. You describe what you want to build in plain English. PDD Kit captures your objective, what we call your intent, and uses a verifier tool to prove the code meets it for every possible input.
You never review a single line of the code or the proof. You review your plan and the defined objectives in natural language.
A simple example is login. With testing, you check that only the correct password logs in a user but with a proof on top you can verify that there is no case a wrong password allows login. You can prove correctness and security across many complex scenarios.
Not only does PDD Kit prove the correctness of your code, but also your intent so you can have confidence your code is correct and does what you asked. It provides a level of assurance that specs, code review, and tests never could. PDD Kit is in limited research preview. Video explainer below.
If you want to learn more, I'll be sharing PDD Kit at GitHub Universe next week, Oct 28–29. Swing by the Speakeasy, ask for GitHub Next, and ask me about verified code. If you're in SF, let me know.
*Yang et al., "(When) Should a Software Factory be Lights-off?", Microsoft Research and CMU, Oct 2026
Let me cook đź‘€
Excited to announce the Cosign Awards: celebrating exceptional people, companies, and products that had a massive impact in 2026.
cosign.co/awards
Anyone can nominate and vote. Award winners will be chosen by the public in conjunction with a panel of judges, including industry leaders like @lennysan, @packyM, @amasad, and many more. We’ll host an event in December honoring the winners (10 per category).
For people categories, we’re mostly focused on everyone except the CEO–everyone else building the company behind the scenes.
Companies with the most amount of people nominations will be listed on our “Top Companies to Work For” page.
True to form, at Product Hunt I helped launch the Golden Kitty awards a decade ago to recognize great products. Soon after I launched the Rise Awards, honoring executives and ICs building companies that make them. The Cosign Awards is the next iteration.
We have 41 categories across people, companies, and products.
People categories:
- Future Founders
- Rising Stars
- Engineering
- FDE
- Product
- Design
- AI Researchers
- Marketing
- Comms
- Growth
- Chief of Staff
- Operations
- Talent
- Finance
- Public Intellectuals
- Podcaster of the Year
- Newsletter Author of the Year
- Poster of the Year
Company categories:
- Rising Stars
- Best Place to Work
- Founder Mafia
- Talent Density
- Highest Aura
Product categories:
- Product of the Year
- Launch of the Year
- AI Assistant
- AI Language Model
- AI Coding
- Dev Tools
- Open Source
- Consumer
- Productivity
- Creative & Media Tools
- Product Design & UX
- Enterprise B2B
- Hardware
- Robotics
- Self-Driving
- Healthcare
- Vertical Fintech
- Legal
I asked Gemini 4 Argon for a Mac voice app like Wispr Flow that talks to my Grok Bot.
Try one came back as a web app. Try two was native, it works, and it looks so ugly.
Try three, Argon takes the clean up with Dieter Rams in mind. Strip the color, one intent on screen.
Ray Fernando retweeted
there's something really cool about asking your agent to draw a statechart (hypothetical example in this image), then using the /create-formal-verification-skill you made with pstack to find bugs through something like TLA+. you can both understand your code better and how the user flow should work, and fix issues users would otherwise see
pstack v0.15.27 ships with a new skill /create-formal-verification-skill!
it's still in beta, and similar to /create-verification-skill, this is a meta-skill that creates a new skill and formal verification suite based on the characteristics you want to verify. for example, you may want to model state machines and systems with concurrency using TLA+, or use kani in rust to check for undefined behavior.
if you're new to formal verification, think of it as mathematically proving properties and invariants (something that must always be true) or "laws" of your system. usually, this means modeling your programs in a separate language like with TLA+ and then running the solver on that spec. newer approaches like with kani and @bendlang take a different approach where there is no separate language: you write kani in rust, and bend in bend (it's also a programming language, and the proofs are written as laws and expressed in its type system).
historically formal verification never reached mainstream status because of the difficulty in modeling and writing proofs. it's quite difficult to model your business requirements and keep them in sync! but i expect that we will see more innovation in formal verification in the future as being able to formally verifiy that the code does what you intended gives your agents superpowers in writing correct software.
in the meantime though, i've been experimenting with modeling our code with TLA+ and have already found several bugs with the skill created by /create-formal-verification-skill.
try it out and let me know how it goes!
As soon as you put a wall in the way, millimeter wave is done.
It's the super fast 5G, and it only really works close to the tower with line of sight. Turn a corner or walk inside and it goes away.
Sub-6 is slower but it reaches way farther, so inside my house I basically can't use millimeter wave.
Great tip from Max to get instant unlock with Duo. Are you ready??
Ray Fernando retweeted
And it’s live! My iPhone Duo review. For seven days and seven nights, I’ve been testing the crap out of this thing—including folding it over 32,000 times with a custom-built folding machine. Go watch!
🤖 Made with AI
T-Mobile is the only US carrier doing iPhone Handoff so far.
You can have two iPhones on one phone number and pick which one is active. Going to the gym, I'd bring the smaller phone and switch my number to it.
The Duo at home turns into basically an iPad. iMessage and Wi-Fi calling still work, just no cell tower.
A family member or a loved one falls and can't get up.
I'm training a tiny robot duck in a simulator to walk up, see them, and say they need help, with the pictures staying on my own computers at home.
Next it texts me or my Grok Bot and calls for help.
Ray Fernando retweeted
“But the code review process is what creates the risk.”
@thorstenball and @sqs on 4,000-line PRs on a Friday, branches nobody remembers, and what continuous integration actually means.
21 people, a single meeting a week, no quarterly goals, no pull requests, no mandatory code review, no titles (except one dictator), a hundred releases a day, bugs fixed in minutes, famous for killing features.
@sqs and @thorstenball on how the Amp team works:
Ray Fernando retweeted
🚨iPhone Duo reviews have dropped! Ones to watch:
@JoannaStern youtu.be/bxDTWuL9GxY?si=Nfln…
@MKBHD youtu.be/ESABTN4VtrA?si=JTMC…
@stalman youtu.be/dxF1r2BMqjU?si=R0fE…
@reckless youtu.be/g5gptFkgBlI?si=9K62…
On the iPhone Duo folded shut, the stuff that used to be at the very top of your iPhone, like the time and the back button, is now on the side.
There's a bottom bar closer to your thumb, and when you open it up it all moves back to the top in the wider layout.
It's a whole new language for developers to adopt.
Every new model tops a leaderboard, and those tests only show one sliver of what an agent can do.
But Ray, the scores are right there.
Test a kid only on cooking one meal and you'd miss that she draws things that make people cry. I want to know if a model can run a crew of agents for a long time and keep up as the world changes, so my bot strategy is one smart bot that runs the rest.
0:00 What's the state of the art?
1:42 The kitchen test
4:11 Crawl, walk, run: my bot strategy
Ray Fernando retweeted
Addressing some questions.
I’m partway through Zuck’s interview on Rogan, and I heard this and wanted to share. I’m excited to listen to the rest.
@zuck @joerogan
Having worked in Integrity, I think the transition from third-party fact checkers to Community Notes is a fantastic idea. I like how Zuck was willing to adapt his model based on new data. Should I make a video talking about this?
I had the privilege to work with some of the smartest people I’ve ever met during my time at Meta. Plus, they were deeply passionate about what they did.
Here are the coding guides I’m referring to:
Coding in AI 101 Guide: Check link in bio!
Fine-tuning guide: youtu.be/kmkcNVvEz-k
Hi, I’m Harper, AI educator, engineer and advisor.
••• My goal is to democratize AI, so everyone can understand it, use it, and make informed decisions about it. Happy you’re here. •••
I have two degrees in Computer Science specializing in Artificial Intelligence from @Stanford, experience teaching PhD-level AI courses there, and 4+ years building AI at @Facebook / @Meta. I was Founding Engineer and then Head of AI at a startup that was acquired by @NVIDIA, and that's where I began my AI teaching journey.
Follow me if you want to learn about AI, and let me know in the comments if there’s anything specific you want to learn about.