# Brad Fitzpatrick on Reddit (u/bradfitz)

Part of Founders and CEOs on Reddit, researched with Autumn (https://www.autumn.ai) from public sources. Updated 2026-11-07. Interactive version: https://www.autumn.ai/resources/founders-on-reddit/brad-fitzpatrick

Brad Fitzpatrick: Founder of LiveJournal, creator of memcached, now at Tailscale.

- Reddit account: [u/bradfitz](https://www.reddit.com/user/bradfitz/) (Personal account)
- How we know it's theirs: ["Tailscalar" flair from r/Tailscale's moderators, who flair Tailscale staff](https://www.reddit.com/r/Tailscale/comments/1cv3tho/i_cant_login_to_my_account_horrible_experience/l4n1fym/)
- Where they post, in the records we retrieved: r/programming (8), r/golang (7), r/Tailscale (4), r/Android (2), r/pics (2), r/linux (1)
- Known activity in the posts we found: 2010 to 2026
- Wikipedia: https://en.wikipedia.org/wiki/Brad_Fitzpatrick

## Moments

### u/bradfitz in r/programming, Jan 7, 2016 · Early days

Replying to a redditor:

> I still remember that moment of horror when I realized why everyone using distributed hash tables (eg, memcache) weren't as crazy as they looked. Caching is one of the hardest things to do properly. Why on earth would you build all that stuff if you had any other option? We had…

> Amusing in retrospect: I never even measured the speed of the disk vs the network when I wrote memcached. I just knew the disks were so damn slow and the root of all our performance problems, so the network couldn't be worse. Prototyped it, it was awesome, and never looked back.

Full thread: https://www.reddit.com/r/programming/comments/3zr68f/nonvolatile_storage_no_longer_true_that_cpus_are/cyorn1y/ · 47 points as of Nov 7, 2026

### u/bradfitz in r/Tailscale, May 18, 2024 · Fixed it

Replying to the post "I can't login to my account, horrible experience after using Tailscale for 2 years".

> Whoops. Thanks for the report.
>
> That code was just refactored and a bug was introduced that only affected old GitHub accounts. (the bug was when certain lazy migrations happened)
>
> A fix is rolling out now.

Full thread: https://www.reddit.com/r/Tailscale/comments/1cv3tho/comment/l4n1fym/ · 11 points as of Nov 7, 2026

### u/bradfitz in r/Tailscale, May 22, 2025 · Owned it

Replying to the post "Someone just randomly joined my Tailnet".

> Tailscalar here.
>
> Yeah, this sucks.
>
> We’re working on changing the identity model. (how users/domains/tailnets all map to each other)
>
> When we first started, we were trying to make it easy for companies to sign up and start working with their coworkers, but we had a special case for @[gmail.com](http://gmail.com) users getting their own tailnets (because at the time, we only supported Google Auth). Later we added GitHub, and GitHub special cases for individuals vs orgs (which nicely mapped to our single-user vs multi-user tailnets).
>
> Over time, we added more auth providers like (and BYO-OIDC) and this whole assume-a-multi-user-tailnet-unless-gmail-and-192-other-shared-email-hosts model really fell apart. We "decompose" (add to our shared email domain list) tailnets every month or so as we find them. We didn’t have your domain on our list previously.
>
> We’re in the middle of changing the identity model to make this class of problem go away entirely, though.
>
> Meanwhile, we just chatted about it and seems like the quickest thing we can do here is turn on User Approvals for all new tailnets so at least the admin of new tailnets like yours has to approve people joining them.
>
> \[Edit May 28: see [https://www.reddit.com/r/Tailscale/comments/1kxwtu5/shared\_domains\_security\_bulletin/](https://www.reddit.com/r/Tailscale/comments/1kxwtu5/shared_domains_security_bulletin/) for the security bulletin\]

Full thread: https://www.reddit.com/r/Tailscale/comments/1ksy3xy/someone_just_randomly_joined_my_tailnet/mtqd4et/ · 1 points as of Nov 7, 2026

### u/bradfitz in r/Android, Dec 6, 2010 · Behind the scenes

Replying to a redditor:

> There's a lot of developer changes that are of interest. In particular, StrictMode is supposed to help you figure out if you're unnecessarily using network/cpu.

> Yeah, I'm particularly excited about StrictMode.  (but I'm also the author of it :))
>
> StrictMode (http://developer.android.com/reference/android/os/StrictMode.html) is not about *unnecessarily* using network or CPU but about doing it on the *correct thread*  (and it's about network or disk, not CPU)
>
> To run a 60 fps animation, you only have 16 ms in your main thread (UI thread) callbacks before you stutter an animation.  Or 5000 ms to bring up an ANR dialog.  Anything between 16 ms and 5000 ms is "janky", though (unresponsive, not pleasant).
>
> Given that the disk (and especially the network) can take longer than 16 ms, StrictMode helps you find places where you unknowingly use one of them.  It's often the case that you didn't hit the disk directly, but some API you used hit the disk via IPC calls across 2 or more processes.  And that process might have to wait for the system-wide yaffs lock (on devices that use yaffs) before it could even start the read/write.  And it it's a write, the flash chip (whether MTD or a FTL emulating a block device) may have to do some slow GC, making some writes slower than others.
>
> In any case, you should get off the UI thread if there's any risk you might take longer than 16 ms.
>
> Gingerbread has hundreds of such fixes using data we've collected from internal dogfooding.  We setup our dev builds to write all disk/network violations to the DropBox (http://developer.android.com/reference/android/os/DropBoxManager.html) and setup our dev builds' DropBox to upload them to servers to run mapreduces over.  Every hour we'd have a new dashboard of the top offenders (count, total latency jank, etc), fixing as many as possible both in apps and in the system (various core services, providers, etc).
>
> I saw the transition slowly, but friends who have switched right from Froyo (which was already pretty fast!) to Gingerbread tell me that it's noticeably smoother & more responsive across the board.  A large part of that is also the concurrent Garbage Collector in Dalvik.
>
> Anyway, bunch of exciting stuff in Gingerbread.
>
> (this comment is long... I should write a blog post.)

Full thread: https://www.reddit.com/r/Android/comments/eh2jf/gingerbread_aka_android_23_is_out/c181i0o/ · 181 points as of Nov 7, 2026