How mainframe-era techniques and native browser APIs outperform modern frameworks

The Numbers

Before the philosophy, the receipts:

Frontend (multicardz.com):


 32KB JavaScript bundle (15% of minified React)
 <100KB total payload including HTML, CSS, fonts, everything
 0ms Total Blocking Ti

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A developer achieves exceptional performance metrics (100 Lighthouse score, 0ms Total Blocking Time, 32ms queries) by rejecting modern frameworks in favor of older techniques. The approach uses DATAOS (DOM As The Authority On State), treating the DOM itself as the state container instead of maintaining separate state objects, eliminating reconciliation overhead. On the backend, 1972-era bitmap indexing with RoaringBitmaps enables constant-time queries regardless of dataset size. The resulting application uses 32KB of vanilla JavaScript (15% of React's size) with a total payload under 100KB, demonstrating that native browser APIs and decades-old database techniques can outperform contemporary frameworks for most web applications.

The Old Ways Are the Best: 100 Lighthouse, 0ms TBT, 32ms Queries

I like the mentality, but using the DOM as an authority to app state feels foreign and possibly fragile to me. It’s very interesting though.

Amen, but I do think the page is not a page you can compare against…

Yet it does not work properly on mobile …

Old ways are the best in terms of simplicity and performances of course, but I don’t think the same could be said in terms of scalability unfortunately. Those technologies where born in an era where computational resources where poor, so they obviously are faster and lighter, but do you think it would really be possible to build big now day’s huge enterprise applications that we are used to see?