Build Log

The build.
Documented.

Hardware fails. Coaches push back. Plans change. This is the real version of building Slingshot: every decision, every dead end, and what the data actually said. We're three founders building it in the open, not optimizing for a pitch.

05

Nineteen messages. One answer we could use.

We restarted outreach in July because the engineers were blocked on trainer language. Here is what nineteen messages produced, and why the reply rate turned out to be the wrong thing to be pleased about.

Live
04

V2 is real, and it's already being built.

The second board is designed and in production. What we changed from V1 and why, from the power chain to the optics, plus why it's being built by a new factory after the last one couldn't deliver on time.

Live
03

We ordered the board. And we already know what V2 changes.

The design left our hands and became a board on its way to us. No undo on copper. The band and casing come together while we wait, plus the honest list of what designing V1 already taught us to change for V2.

Live
02

What we're about to find out when we build the first board

Next: the first real sensor pod. Before we trust a board layout, we have to know whether heart rate even survives on the upper arm during live play. It's the one result that could force a redesign. Here's the bet, and how we'll know if it paid off.

Live
01

Could a stopwatch replace us?

A co-founder asked whether a stopwatch and a good eye could do what Slingshot does. It's a fair question. The answer is the reason we're building this.

Live
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