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Jack Ellis
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@JackEllis

Jack Ellis

@JackEllis
Software engineer. Building @usefathom since 2019. Sharing all the technical details from behind the scenes.
usefathom.com
Joined May 2008
316 Following
35.4K Followers
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  • Pinned
    @JackEllis
    Jack Ellis
    @JackEllis
    Jul 13
    I’ve spent nearly seven years documenting how we built Fathom: outages, DDoS attacks, migrations, $100k AWS savings, my cofounder’s retirement, and a divorce. I write transparently because I want other people to learn from my mistakes. These 18 posts tell the story:
    25
  • @JackEllis
    Jack Ellis
    @JackEllis
    10h
    I'm 20 more hours into undoing a lot of bad decisions Opus made that don't scale in production. It's very good at building stuff that works locally which then fails in production. Then it tries to fix it with slop patching. One thing I will say is at least it doesn't deny it.
    @JackEllis
    Jack Ellis
    @JackEllis
    Oct 7
    Software engineering is dead... In other news, a software engineer with 18 years of experience (me) just spent 15 hours refining a big new feature, asking questions that the frontier models hadn't even considered. Software engineering isn't going anywhere.
    16
  • @JackEllis
    Jack Ellis
    @JackEllis
    16h
    X is dead, I just vibe coded an alternative and it only cost me $300 in tokens.
    349
  • @JackEllis
    Jack Ellis
    @JackEllis
    Oct 8
    I bet you didn't see this one coming 😇
    We threw out PHP and rewrote our pageview collector in hand-written x86-64 Assembly. Here's what happened to our latency, our AWS bill and our sanity.
    We rebuilt Fathom in Assembly - Fathom Analytics
    From usefathom.com
    75
  • @JackEllis
    Jack Ellis
    @JackEllis
    Oct 7
    Software engineering is dead... In other news, a software engineer with 18 years of experience (me) just spent 15 hours refining a big new feature, asking questions that the frontier models hadn't even considered. Software engineering isn't going anywhere.
    228
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