Groundwork Decision Engine (@gworkycom/engine)

Groundwork Decision Engine is an open-source, zero-dependency suite of evidence-based computational models for personal finance, preventive health, and home energy decisions.

Developed by the Groundwork Research Desk, this library powers the interactive calculators available on gworky.com/tools.

Key Modules

• Solar Panel Payback & ROI: Calculates 20-year net savings, federal ITC tax credits, utility escalation, and break-even periods.
• Mortgage Refinance Break-Even: Computes monthly payment differentials, closing cost amortization, and net lifetime interest savings.
• TDEE & Macronutrient Allocation: Implements the Mifflin-St Jeor equation with validated activity multi-tiers.
• Zone 2 Cardiovascular Physiology: Calculates lactate threshold training heart rate zones for mitochondrial density.
• HVAC Psychrometric Sizing: Simplified Manual J heating/cooling load and CFM airflow estimator.

Installation

npm install @gworkycom/engine

or with yarn / pnpm:

pnpm add @gworkycom/engine

Quickstart

1. Solar Payback & 20-Year Net Savings

import { calculateSolarPayback } from "@gworkycom/engine";

const result = calculateSolarPayback({
  systemCost: 20000,
  annualOutputKwh: 9000,
  electricityRatePerKwh: 0.16,
  federalCreditRate: 0.30, // 30% Residential Clean Energy Credit
  annualUtilityIncreaseRate: 0.03, // 3% annual escalation
});

console.log(result);
// {
//   netCost: 14000,
//   firstYearSavings: 1440,
//   paybackYears: 8.4,
//   twentyYearNetSavings: 24890.12
// }

2. Mortgage Refinance Break-Even

import { calculateMortgageRefinance } from "@gworkycom/engine";

const refinance = calculateMortgageRefinance({
  currentBalance: 350000,
  currentRate: 0.06875, // 6.875%
  newRate: 0.0575,      // 5.750%
  closingCosts: 4500,
  remainingTermMonths: 320,
  newTermMonths: 360,
});

console.log(`Monthly Savings: $${refinance.monthlySavings}`);
console.log(`Break-even: ${refinance.breakEvenMonths} months`);

Interactive Web Demos & Documentation

All mathematical formulas, underlying peer-reviewed literature, and interactive web calculators are maintained at:

• Interactive Calculators: https://gworky.com/tools
• Embed Generator: https://gworky.com/embed-builder
• Citations & Research Methodology: https://gworky.com/citations
• Open Science DOI Archive: https://doi.org/10.5281/zenodo.22011566

License

MIT © Groundwork Media