Mahdi Yusuf
@mahdiyusuf.com
Sr. Engineering Manager @ Apple. Distributed Systems and Data. Previously @ 1Password.
Homelabs, databases, and basketball.
✍🏾 @architecturenotes.co
Homelabs, databases, and basketball.
✍🏾 @architecturenotes.co
Pinned
Reposted by Mahdi Yusuf
At 250 billion DNS cache entries, one wasted byte costs 250 GB of RAM.
Five Rust optimizations later: 100 TB freed, inserts 43% faster, lookups 19% faster.
We didn't trade speed for space. https://cfl.re/4wOegyp
Five Rust optimizations later: 100 TB freed, inserts 43% faster, lookups 19% faster.
We didn't trade speed for space. https://cfl.re/4wOegyp
How we saved 100 terabytes of memory by optimizing 1.1.1.1’s DNS cache
Five Rust-level memory optimizations to the DNS cache layout of Big Pineapple cut per-entry memory by 56%, freeing approximately 100 TB of memory across Cloudflare's fleet.
blog.cloudflare.com
August 27, 2026 at 5:45 PM
At 250 billion DNS cache entries, one wasted byte costs 250 GB of RAM.
Five Rust optimizations later: 100 TB freed, inserts 43% faster, lookups 19% faster.
We didn't trade speed for space. https://cfl.re/4wOegyp
Five Rust optimizations later: 100 TB freed, inserts 43% faster, lookups 19% faster.
We didn't trade speed for space. https://cfl.re/4wOegyp
@larchuk.bsky.social did you reach out to me on twitter? dm?
August 12, 2026 at 1:39 AM
@larchuk.bsky.social did you reach out to me on twitter? dm?
Reposted by Mahdi Yusuf
August 2, 2026 at 1:41 AM
August 2, 2026 at 1:41 AM
@softwaredoug.bsky.social can I buy some of your old courses still or enroll in them and get the content now? It’s inconvenient to have to wait for course dates.
July 18, 2026 at 12:52 AM
@softwaredoug.bsky.social can I buy some of your old courses still or enroll in them and get the content now? It’s inconvenient to have to wait for course dates.
Reposted by Mahdi Yusuf
iddqd, or the hardest kind of unsafe Rust.
My first post for the @oxide.computer blog! Goes deep into the pitfalls of unsafe Rust and how to reason about it. A lot of labor went into the post -- please have a read!
oxide.computer/blog/iddqd-u...
My first post for the @oxide.computer blog! Goes deep into the pitfalls of unsafe Rust and how to reason about it. A lot of labor went into the post -- please have a read!
oxide.computer/blog/iddqd-u...
iddqd, or the hardest kind of unsafe Rust | Oxide Computer Company
How our Rust collections library defends against adversarial trait implementations.
oxide.computer
June 2, 2026 at 3:32 PM
iddqd, or the hardest kind of unsafe Rust.
My first post for the @oxide.computer blog! Goes deep into the pitfalls of unsafe Rust and how to reason about it. A lot of labor went into the post -- please have a read!
oxide.computer/blog/iddqd-u...
My first post for the @oxide.computer blog! Goes deep into the pitfalls of unsafe Rust and how to reason about it. A lot of labor went into the post -- please have a read!
oxide.computer/blog/iddqd-u...
Speed Tax www.mahdiyusuf.com/the-speed-tax/
The Speed Tax
Speed is seductive, but unchecked velocity creates hidden risk. When building gets cheaper, scrutiny disappears—leading to security gaps, product bloat, and cultures that reward shipping over thinking...
www.mahdiyusuf.com
April 21, 2026 at 11:45 AM
Speed Tax www.mahdiyusuf.com/the-speed-tax/
So what do people think about sliced tomatoes on a pizza?
February 16, 2026 at 11:02 PM
So what do people think about sliced tomatoes on a pizza?
Reposted by Mahdi Yusuf
America outsourced manufacturing, then the skills to design what gets manufactured. Software is next.
mahdiyusuf.com/the-journey-...
mahdiyusuf.com/the-journey-...
The journey was the point
America outsourced manufacturing, then the skills to design what gets manufactured. Software is next.
mahdiyusuf.com
February 12, 2026 at 7:30 PM
America outsourced manufacturing, then the skills to design what gets manufactured. Software is next.
mahdiyusuf.com/the-journey-...
mahdiyusuf.com/the-journey-...
America outsourced manufacturing, then the skills to design what gets manufactured. Software is next.
mahdiyusuf.com/the-journey-...
mahdiyusuf.com/the-journey-...
The journey was the point
America outsourced manufacturing, then the skills to design what gets manufactured. Software is next.
mahdiyusuf.com
February 12, 2026 at 7:30 PM
America outsourced manufacturing, then the skills to design what gets manufactured. Software is next.
mahdiyusuf.com/the-journey-...
mahdiyusuf.com/the-journey-...
I built more with AI agents in two months than the previous year. I used almost none of it. The real productivity gain isn't building—it's using.
mahdiyusuf.com/your-agent-i...
mahdiyusuf.com/your-agent-i...
Your agent is building things you'll never use
I built more with AI agents in two months than the previous year. I used almost none of it. The real productivity gain isn't building—it's using.
mahdiyusuf.com
January 24, 2026 at 4:49 PM
I built more with AI agents in two months than the previous year. I used almost none of it. The real productivity gain isn't building—it's using.
mahdiyusuf.com/your-agent-i...
mahdiyusuf.com/your-agent-i...
Reposted by Mahdi Yusuf
Wrote something about the importance of the code generation and library use in the context of agents.
mahdiyusuf.com/agents-didnt...
mahdiyusuf.com/agents-didnt...
Agents didn't kill libraries—they just changed the math
I've been writing software long enough to remember when "don't reinvent the wheel" was gospel. Find a library. Import it. Move on. The assumption was clear: someone else's maintained code beats your o...
mahdiyusuf.com
January 4, 2026 at 6:28 PM
Wrote something about the importance of the code generation and library use in the context of agents.
mahdiyusuf.com/agents-didnt...
mahdiyusuf.com/agents-didnt...
Sparking up the blog again and decided to write some inference into the blog. There a few other spots where you can see it in action as well. Check it out.
January 4, 2026 at 5:54 PM
Sparking up the blog again and decided to write some inference into the blog. There a few other spots where you can see it in action as well. Check it out.
Experimenting with a Touch ID wrist rest 👀
Early prototype, lots to refine—but the idea feels right.
Early prototype, lots to refine—but the idea feels right.
January 1, 2026 at 6:53 PM
Experimenting with a Touch ID wrist rest 👀
Early prototype, lots to refine—but the idea feels right.
Early prototype, lots to refine—but the idea feels right.
MCPs give me the same energy as GraphQL: works just well enough that people adopt it, just poorly enough that you inherit a new class of problems.
Both exist because building proper context and tooling takes effort. Most would rather reach for something "good enough."
Both exist because building proper context and tooling takes effort. Most would rather reach for something "good enough."
December 27, 2025 at 6:03 PM
MCPs give me the same energy as GraphQL: works just well enough that people adopt it, just poorly enough that you inherit a new class of problems.
Both exist because building proper context and tooling takes effort. Most would rather reach for something "good enough."
Both exist because building proper context and tooling takes effort. Most would rather reach for something "good enough."
MCPs give me the same energy as GraphQL: works just well enough that people adopt it, just poorly enough that you inherit a new class of problems.
Both exist because building proper context and tooling takes effort. Most would rather reach for something "good enough."
Both exist because building proper context and tooling takes effort. Most would rather reach for something "good enough."
December 27, 2025 at 5:45 PM
MCPs give me the same energy as GraphQL: works just well enough that people adopt it, just poorly enough that you inherit a new class of problems.
Both exist because building proper context and tooling takes effort. Most would rather reach for something "good enough."
Both exist because building proper context and tooling takes effort. Most would rather reach for something "good enough."
Playwright MCP is too token heavy what else people using?
December 27, 2025 at 5:15 PM
Playwright MCP is too token heavy what else people using?
Reposted by Mahdi Yusuf
First custom keyboard build ✅
Split layout, fully custom case + PCB — designed from scratch and 3D-printed. Still a work in progress, but seeing it come together is fun.
Firmware next.
Split layout, fully custom case + PCB — designed from scratch and 3D-printed. Still a work in progress, but seeing it come together is fun.
Firmware next.
December 20, 2025 at 9:33 PM
First custom keyboard build ✅
Split layout, fully custom case + PCB — designed from scratch and 3D-printed. Still a work in progress, but seeing it come together is fun.
Firmware next.
Split layout, fully custom case + PCB — designed from scratch and 3D-printed. Still a work in progress, but seeing it come together is fun.
Firmware next.
Anyone have a cool set up for iPadOS for running terminals for using Claude code?
December 23, 2025 at 9:11 PM
Anyone have a cool set up for iPadOS for running terminals for using Claude code?
First custom keyboard build ✅
Split layout, fully custom case + PCB — designed from scratch and 3D-printed. Still a work in progress, but seeing it come together is fun.
Firmware next.
Split layout, fully custom case + PCB — designed from scratch and 3D-printed. Still a work in progress, but seeing it come together is fun.
Firmware next.
December 20, 2025 at 9:33 PM
First custom keyboard build ✅
Split layout, fully custom case + PCB — designed from scratch and 3D-printed. Still a work in progress, but seeing it come together is fun.
Firmware next.
Split layout, fully custom case + PCB — designed from scratch and 3D-printed. Still a work in progress, but seeing it come together is fun.
Firmware next.
Has anyone set up a self hosted ghost instance using 6.0 and manage to get up with new built in activity pub integration?
August 16, 2025 at 10:34 PM
Has anyone set up a self hosted ghost instance using 6.0 and manage to get up with new built in activity pub integration?