A map app that finds where both partners can live within their commute limits

A developer built a personal tool to find neighborhoods where both they and their partner could reach their separate workplaces within a set commute time — using real travel time, not straight-line distance. It was made to solve a real relocation decision and shared as a side project.

When two people work in different places and need to find a home together, picking the geographic midpoint often doesn't work well. A spot that looks central on a map might have poor transit connections, making both commutes long. Meanwhile, a location slightly closer to one job might actually work better for both people.

This tool lets users enter two work addresses and a maximum commute time, then highlights on a map every area where both people can reach their offices within that limit — using real public transit or driving times. The creator built it to settle a personal debate with their partner about where to move, then published it publicly. It resonated because many couples face exactly the same problem, making it a strong example of building a niche tool around a very concrete personal need.

Key points

  • Enter two work addresses and a time limit — the map shows every neighborhood both people can reach in time
  • Uses real transit/driving times, not straight-line distance, so results reflect reality
  • Built to solve the creator's own relocation problem, then released publicly
  • Classic solo-builder move: your specific problem is often someone else's problem too
  • Niche tools that solve one concrete life decision tend to attract strong word-of-mouth

Quick term guide

persona
A specific personality or role that an AI agent is set to play.
share
A server folder made available to apps or other devices.
side project
A small project someone builds outside their main job or main business.
diff
A view that shows exactly what changed in the code.
TRON
A compact data format made to describe tool use with fewer words for AI systems.
build
A chosen set of in-game abilities or items a player equips for their character.
niche
A very specific, narrow segment of a market or customer group.
spec
A written document describing exactly what a piece of software should do before you build it.
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