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System Deep Dive

Snapshot: March 2026

Boosted Charge, ML-powered placement intelligence for physical revenue assets.

A revenue forecasting and venue recommendation engine for phone charging kiosks. XGBoost with Optuna hyperparameter tuning, a 35-feature engineering pipeline spanning weather, demographics, foot traffic, and venue quality, 7 external API connectors, a weighted scoring algorithm that explains every rank, and 140 passing tests behind the forecasting stack.

  • 35engineered features
  • 7API connectors
  • 12database tables
  • 140tests behind the model stack
Abstract systems diagram for Boosted Charge

ML Pipeline

XGBoost, Optuna, and time-series cross-validation.

The model predicts daily revenue per kiosk 7–14 days out. Training uses TimeSeriesSplit to respect temporal ordering. Optuna tunes hyperparameters. A model registry tracks versions, metrics, and promotion.

Training and prediction
  • XGBoost regressor with 200 estimators, depth 6, subsample 0.8
  • Optuna hyperparameter optimization
  • TimeSeriesSplit cross-validation (temporal ordering preserved)
  • Metrics: MAE, MAPE, RMSE, R2 — tracked per model version
  • Model registry with versioning, artifact storage, and promotion
Feature engineering (35 features)
  • Time-based (6): day of week, weekend, holiday, daypart weighting
  • Weather (7): temp range, precipitation, comfort score, extreme flags
  • Venue (8): type encoding across 14 categories, ratings, price level
  • Foot traffic (4): Yelp checkins, Google popularity, nearby events
  • Demographics (5): population, median income, age cohorts from Census
  • Lag features (5): rolling means and recent revenue patterns

Data Layer

Seven connectors. Five ETL pipelines. Cron-scheduled.

Connectors
  • Stripe — transaction data and revenue history
  • Open-Meteo — historical and forecast weather (free)
  • Google Places — venue discovery and place details
  • Yelp Fusion — ratings, reviews, checkin counts
  • Ticketmaster + Eventbrite — nearby event signals
  • US Census Bureau — demographics by tract
ETL scheduling
  • Transactions synced every 15 minutes from Stripe
  • Weather refreshed every 6 hours
  • Venue metrics updated daily at 2 AM
  • Events synced daily at 3 AM
  • APScheduler cron with background execution
Venue scoring
  • Predicted revenue (30%), foot traffic (25%)
  • Demographics (20%), competition (15%), venue quality (10%)
  • Per-signal breakdowns for explainability
  • Candidate venues ranked with composite scores

Stack

Python, FastAPI, PostgreSQL, XGBoost.

  • Python
  • FastAPI
  • PostgreSQL
  • SQLAlchemy 2.0
  • Alembic
  • Docker
  • XGBoost
  • Optuna
  • scikit-learn
  • pandas
  • APScheduler
  • Stripe

Need ML that explains its recommendations, not just outputs them?

That takes feature design, connector discipline, and a scoring model built for operators.

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