I always wanted to be a developer, and it was quite long time that I was planning to get fit and change my habits (smoke, fast food, alcohol, and so on)

I run a food business (American style potato rolls), and definitely I'm not a developer, even tho I've been working as project manager for a decade being the intersection between designers and developers. At the end of 2024 something changed in me, so I started my Project Riace to get fit, and while doing this I built an app that helped me on my plan.

Starting at 87.8 kg with 28% body fat, I'm now 72 kg with 11% body fat, without losing any muscles (actually I gained about 1kg) and this thanks to a nutritionist, a personal trainer and lot of tennis. No shortcuts, just eating well and training seriously each day, starting from 10 minutes each morning, every morning.

Why I'm telling you this? Because I'm in this new better version of me, thanks also to AI.

I trained Claude with my nutritional plan made by my doctor, my exercise made by my trainer, and my goal for this summer — it has been like having a 24/7 nutritionist and personal trainer in my pocket.

But, I'm here to show you the app I made, obviously called "riace." — it's an interval timer for workouts (tabata, emom, recovery, timer) with voice control, and a personal spin on the visual part to visualise the time spent training. It's a free app, no subscriptions, no account, nothing. Just your training side-kick, as it was for me.

It has been fully built with Replit, with the help of Claude on certain parts. I orchestrated everything, tested, refined, iterated and made the UI/UX. I know here many of you are real developers, but for me this tool (Replit) is a life changer. I can finally build what I have in my mind.

The project actually started from an idea I had using a led bar timer with Arduino, which I actually built, but paused for the moment because I want to make one step at a time.

This app won't change your life, I didn't reinvent the wheel, but it changed my life! Going from an iPhone pics folder called "Road to Canotta" (Road to tank top) in 2016, now I can finally walk on the street proud of my body and with an app made by me in my phone, and hopefully yours.

Happy to answer any question!

Show HN: Riace – a hands-free interval timer I built while getting back in shape