Built In Public
SubmitSign in
Built In PublicProductsMario’s Newsletter | Substack

Mario’s Newsletter | Substack

Product engineer building with AI. Writing about what ships. Click to read Mario’s Newsletter, by Mario Hayashi, a Substack publication. Launched a year ago.

Added 6 Sept 2026
UnspecifiedIn development
0
Visit site
Screenshot of Mario’s Newsletter | Substack
Screenshot of the live site, captured 6 Sept 2026.blog.mariohayashi.com/?via=buildinpublic
Built by

Who's building it

@logicalicy
No activity measurement recorded yet. This does not affect discovery eligibility.
View profile →
Also building
Mario’s Newsletter | Substack is the only product Mario Hayashi has listed
What shipped

Everything that shipped, and what didn't count

How events are classified →
Nothing ingested yet
Ship events appear here within an hour of the first sync after an account is connected.
Elsewhere on the site

More work in progress

All products →