Mortimer – Canadian Mortgage Insights

A privacy-first Progressive Web App for simulating mortgage paydowns, comparing renewal and refinancing rates, and planning home equity (HELOC) borrowing — tailored for Canadian mortgages.

All calculations run entirely in your browser. No data is collected, stored, or transmitted to any server.

Features

• Dashboard — At-a-glance summary of your mortgage profile including remaining balance, interest paid, and time saved.
• Paydown Simulator — Model lump-sum payments, double-up schedules, payment increases, and see how they shorten your amortization.
• Rates Comparer — Compare renewal offers and refinancing scenarios side-by-side, including IRD and three-month interest penalties.
• Reno & HELOC Planner — Estimate home equity available for a HELOC and plan renovation financing.
• Settings & Privacy — Export/import profiles, enable passcode encryption, and clear all data.

Canadian Mortgage Math

Mortimer uses semi-annual compounding (Canada's standard) to calculate effective periodic rates across all supported payment frequencies:

• Monthly
• Semi-monthly
• Bi-weekly (regular and accelerated)
• Weekly (regular and accelerated)

Privacy & Compliance

• 100% client-side — no backend, no analytics, no cookies
• Optional passcode lock with Web Crypto key derivation
• PIPEDA and Loi 25 (Quebec) compliant
• Data stored only in browser localStorage

Tech Stack

• React 19 + TypeScript 6
• Vite 8
• Chart.js + react-chartjs-2
• Lucide React icons
• Oxlint for linting
• PWA with service worker and web manifest

Getting Started

npm install
npm run dev

Build for production:

npm run build
npm run preview

Testing & Coverage

npm test              # run the Vitest suite once
npm run test:watch    # watch mode
npm run test:coverage # run tests and generate a coverage report (./coverage)

Coverage is collected with the V8 provider. CI runs test:coverage on every push and pull request: results are posted as a comment on the PR, and the full HTML report is uploaded as the coverage-report artifact on each CI run (open index.html after downloading).

Supply Chain / SBOM

Generate a CycloneDX Software Bill of Materials locally:

npm run sbom   # writes bom.json (CycloneDX 1.6 JSON)

CI regenerates this on every run, publishes it as the sbom-cyclonedx build artifact, and scans it for known vulnerabilities with Grype — see SECURITY.md for details.

Deployment

Mortimer deploys to GitHub Pages via the workflow in .github/workflows/deploy.yml.

The workflow uses actions/configure-pages@v5 with enablement: true, which automatically enables GitHub Pages and configures it to build using GitHub Actions — no manual repository settings change required.

Troubleshooting

If the Setup Pages step fails with HttpError: Not Found, ensure the repository has Pages permissions enabled:

1. Go to Settings → Pages in the repository.
2. Under Build and deployment → Source, select GitHub Actions.
3. Re-run the workflow.

License

Released under the MIT License. See LICENSE for details.