I Built BreakFinder: Personalized Surf Forecasts + Full Garmin Ecosystem

Philipp — Sun, 08 Feb 2026 21:00:19 +0000

I Built BreakFinder: Personalized Surf Forecasts + Full Garmin Integration
I try to build something surfers actually needed.

Today I'm sharing the technical journey, what worked, and what I'd do differently.

The Problem:

I'm a surfer. I check forecasts constantly. But here's the thing:

A 6ft beach break ≠ a 6ft reef break

Most forecast apps show you swell size and wind direction. Cool. But they
don't tell you if the break matches YOUR skill level.
Or if you're about to paddle into something dangerous.
So I spent 2 months building BreakFinder to solve that.

The Solution: Three Pillars

Personalized Condition Scores

Instead of generic forecasts, BreakFinder gives you a personalized condition
score based on:

Your preferred wave height range
Your preferred wind direction
Your preferred tide
Your preferred wave period

Example:

Forecast: "6ft swell, 15kt offshore wind"
My app: "🟢 Perfect for you today" (because I'm intermediate + like 4-6ft)
But for a beginner: "🔴 Too big for your level"

Full Garmin Integration (100+ Devices)

This was the hardest part. I integrated with Garmin because I use a Garmin
watch and wanted accurate session tracking.

What's included:

5 Connect IQ apps (Forecast, Session Tracker, Surf Skate Tracker, Watch Face, Breath Training)
Wave counting (how many waves you caught today)
Post-session data sync to your account at BreakFinder

Why it was hard:

Garmin's Connect IQ SDK is powerful but poorly documented. I had to:

Support 100+ different watch models (each with different capabilities)
Handle offline functionality (watches have limited storage)
Optimize for battery life (can't drain your watch)
Build fallbacks when devices don't support certain features

Worth it? Maybe.

Skill-Level Spot Matching

The database of 1500+ spots includes difficulty ratings. So when you're trip
planning, you see:

Beginner spots: Mellow beach breaks
Intermediate: Reefs with some risk
Advanced: Heavy breaks (Sunset, Pipe territory)

The Tech Stack

Fullstack:

Rails 7 (API + Monolith)
Hotwire (Turbo + Stimulus)
PostgreSQL for user data + spots
Redis for caching forecasts
Event-Driven-Architecture

External:

Garmin Connect IQ SDK (C++)
OpenMeteo for first 7 days forecast data
NOAA for 8–16 days forecast data (own blog worth documenting the pain)
Geocoder (Ruby Gem)
Leaflet for spot maps

DevOps:

Docker for dev environment
Hetzner + Kamal (loving it! So easy and cheap)
GitHub Actions for CI/CD

Current Metrics (2 Months In)

5,000 downloads (Garmin IQ Store)
3.9★ rating (honest reviews, we support 100+ devices = some quirks and early version had some major issues like no wave counting at all)
1000+ registered surfers

What's Next

Business Side (Launching Feb 2026)

Here's where it gets interesting. I'm building a marketplace for local
guide operators.

The idea:

Small surf shops, guides, crews can list themselves
Traveling surfers can find them directly
Fair pricing (€19-€299/month per business, NO algorithm trap)
No 30% commission like booking platforms

This is where the real revenue lives. A solo surfer might pay €5/month.
A local business? They'll pay €50-200/month to reach customers.

For Other Solo Devs

If you're building something:

Pick a niche you understand deeply (I am a surf addict)
Focus on one metric early (mine: Garmin support)
Write about the technical journey (not just the marketing angle)

Questions?

I read every comment. Ask me about:

Garmin APIs
Rails architecture
Forecasting algorithms
What I'd do differently
Building as a solo dev

Let's talk! 🏄‍♂️

Forem: Philipp