macOS menu bar app that shows how full the ISS urine tank is in real time

Original Article ↗ Hacker News Discussion ↗

Project motivation & concept

  • Menu bar app shows live ISS urine tank fullness using public telemetry.
  • Creator describes it as a joke and learning exercise: first Swift/macOS app, built “because it was funny” and an excuse to try Swift and menu bar APIs.
  • Several comments praise it as a perfect small practice project and a good model of clearly stating non‑goals (“only the piss tank, nothing else”).

Public ISS telemetry & privacy

  • Many are surprised such detailed life-support data is publicly accessible.
  • Some argue that because the ISS is publicly funded, public telemetry is appropriate.
  • Others raise privacy concerns and joke about extreme analytics (identifying astronauts, social engineering), but an ISS Mimic contributor clarifies that the tank metric doesn’t directly map to each individual toilet use.

Waste handling & space toilets

  • Multiple comments dive into how ISS waste is handled: urine is largely recycled into drinking water; feces are collected in canisters and usually burned up in cargo craft during re‑entry.
  • There is no exposed telemetry for fecal storage, disappointing those hoping for a “poop meter.”
  • Comparisons to Star Trek, The Expanse, Babylon 5, and other pop culture highlight how critical yet under-depicted toilets are in sci‑fi.

Technical details, ports & tooling

  • App uses the ISS Mimic/Lightstreamer feed; some note continuous data (~1 KB/s) and discuss throttling.
  • Ports and related tools include:
    • Web version (single HTML/JS page).
    • Windows versions (.NET and another separate implementation).
    • A Prometheus exporter and SwiftBar/xbar script.
    • A Vision Pro 3D “immersive” urine tank view.
  • One commenter notes how easily LLMs ported the Swift code to a web page, while others describe inconsistent LLM behavior on similar prompts and remain cautious for larger codebases.

Meta: reception, humor & skepticism

  • Enthusiastic responses call it “exactly the kind of hacking” they enjoy; many appreciate the unabashed embrace of “piss” in naming and variable choices.
  • Puns, toilet humor, and imagined use cases (alerts per “whizz,” competitions, Morse-code signaling via tank levels) dominate.
  • Some express mild dismay that such a frivolous post tops HN, but others argue it effectively exposes people to ISS telemetry and open data, potentially inspiring more serious projects.