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PT
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ProductLive

Paneleiro

Live football fan app for iPhone and Android: real-time matches, push notifications and highlights.

Role
Founding Engineer
Period
2025 – 2026
Live siteApp StoreGoogle Play
Paneleiro App website: “Aqui você joga junto”, with App Store and Google Play buttons.

Overview

A football (soccer) fan app for iPhone and Android, published as Paneleiro App. Fans rate players, coaches and referees, build lineups and follow matches live, with push notifications and highlights.

One monorepo holds the Flutter app, the Nuxt admin website and the .NET 8 backend.

What I built

  1. 01Built the .NET 8 Web API behind the mobile app and the admin dashboard: Hangfire recurring jobs monitor live matches and push updates to clients over SignalR, with Sportmonks match data, OneSignal push and a highlights pipeline (ScoreBat + FFmpeg + S3).
  2. 02Fixed connection exhaustion and duplicate notifications on the highest-traffic matches (Brazil national-team games) by replacing per-user parallel HTTPS calls with batched OneSignal sends, and made the “already sent” flag independent of push failures.
  3. 03Added a guard that stops orphaned recurring jobs, data-freshness canaries with email alerts, and a regression test for every production bug. Fixed a canary that had been silently measuring the wrong thing.

Case studies

When a goal in a Brazil match broke push notifications

Problem

During Brazil national-team games, the highest-traffic moments, post-match notifications opened one HTTPS call per user in parallel, exhausted connections and failed. Because the “sent” flag was only set on success, every tick of the recurring job sent the push again, for about 30 minutes.

What I did

  • Switched to batched sends of 100 through OneSignal.
  • Made the “already sent” flag independent of push failures.
  • Added a guard against orphaned recurring jobs, after finding one that had been running every 10 seconds for months: Hangfire persists jobs in MySQL.
  • Added data-freshness canaries with email alerts, and fixed one that was silently measuring the wrong thing.
  • Wrote a regression test for each bug.

Lesson

Design for retries and failure containment, and own production.

Stack

  • C#
  • .NET 8
  • EF Core
  • Hangfire
  • SignalR
  • Redis
  • MySQL
  • Flutter
  • MobX
  • Nuxt
  • Sportmonks
  • OneSignal
  • FFmpeg
  • AWS S3
  • Firebase

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