# BorderLog

> A travel day tracker for digital nomads. Log where you've been and see how close you are to triggering tax residency in each country you visit.

BorderLog helps people who move between countries figure out when they're at risk of becoming a tax resident somewhere. Most jurisdictions check whether you've spent 183 days inside a rolling year. Cross that line and you owe taxes there. BorderLog logs your travel as a sequence of single date entries. Each entry says "from this date, I was here," and stays in effect until the next entry overrides it. The app computes how many days you've accumulated per country and warns when you're getting close to 183.

The app runs in two modes. As a guest, your data lives in the browser's localStorage and stays on the device. Create an account and entries sync across devices, with your guest history imported on signup. Mobile builds for iOS and Android wrap the same web app via Capacitor.

The app is free and the math is open. It ships in 15 languages: English, Spanish, Brazilian Portuguese, French, German, Italian, Russian, Simplified Chinese, Japanese, Korean, Arabic, Hindi, Turkish, Dutch, and Polish. Country names and dates render in the active locale.

## Key concepts

- **Entry.** A single date marker saying "I was in country X starting on this day." It stays in effect until the next entry overrides it.
- **Rolling window.** Most tax authorities count the last 365 days, not the calendar year. BorderLog defaults to a rolling window ending today.
- **Headroom.** Days remaining before you'd hit 183 in a country. The app also shows recovery dates: as old days fall off the back of the window, you regain available days.
- **Future entries.** You can plan trips in advance. The summary shows planned future days separately from days already accumulated.

## Pages

- [Home / dashboard](https://borderlog.com/): Add an entry and see your day count per country with residency alerts.
- [Sign up](https://borderlog.com/auth/signup): Create a free account to sync across devices.

The `/entries` page and `/auth/login` are marked noindex and are only useful to authenticated users.

## What it does not do

BorderLog does not give tax advice. It shows day counts and flags when you're approaching 183 days in the rolling window. The actual rules vary by country. Partial days and tiebreaker treaties can both change the math, and the threshold itself is not always 183. Always confirm your situation with a tax professional.

## Tech

The frontend is a Nuxt 4 app written in TypeScript. The backend is an AdonisJS 7 REST API on a MySQL database. Mobile builds use Capacitor 8 for iOS and Android. Translation files live in `apps/frontend/i18n/locales/`. Country names come from the i18n-iso-countries library so all 251 ISO 3166-1 codes are localized automatically.