Software we build and run ourselves

Five products, designed, built, shipped and supported by S4 Solutions. They are our own software — not client engagements, and we don't present them as client results.

SaaS · Live

KinshipRM

Your relationships, always with you.

A privacy-first personal CRM. Your contacts, conversations and relationship history in a system you own — one that comes with you when you change jobs.

  • Personal and professional contacts, side by side.
  • Privacy-first: your relationship data is held for your use.
  • AI assistance helps you find and recall the detail that matters.
Go to kinshiprm.app About KinshipRM →
KinshipRM app icon.

Game · Free 30-day evaluation on itch.io

Sinews of War: The American Revolution

“Money is the sinews of war.”

A turn-based game of statecraft, 1775–1783. The war is won with money, supply and the loyalty of the people; the battles are fought in real-time 3D, or settled at once.

  • Play the Continental Congress or Great Britain.
  • Real-time 3D battles, or auto-resolve any of them.
  • For macOS, Windows and Linux.
Try it free on itch.io About Sinews of War →
Campaign map of New England in spring 1775, with Washington's Main Army selected at Cambridge and its regiments listed.
A 3D battlefield near Boston: a Continental regiment in line faces British regiments across open pasture.Close view of a regiment in line on the battlefield.

iPhone · On the App Store

safeT1D

Medical apps on. Everything else waits.

School Mode for students with type 1 diabetes. During school hours the phone keeps only the CGM, pump and parent contacts; parents approve changes from their own iPhone.

  • The CGM, pump and parent contacts stay on during class.
  • Parents approve or deny requests from their own iPhone.
  • Never reads glucose readings or any other health data.
Get it on the App Store About safeT1D →
safeT1D on the student's iPhone: School Mode ON, done at 2:01 PM, the Dexcom G7 and Tandem Mobi app tiles, and a yellow Ask a grown-up button.The parent's view: a blue School Mode ON card and control tiles for End now, School hours, Schedule off and Unlock 10 min.

iPhone and iPad · Coming soon

Scytale

An ebook reader for the books you own.

Reads DRM-free EPUB, PDF and comics, and syncs reading progress both ways with your own Calibre server. No account and no store.

  • DRM-free EPUB, PDF and CBZ comics.
  • Two-way sync with your own Calibre server.
  • No ads, no analytics and no tracking.
About Scytale
The Scytale library on iPhone: three book covers in a grid, each tagged EPUB or PDF, under a search field.A Calibre server named Home Library in Scytale: three books listed with their covers, each marked In Library.

Open source · Maintained by S4 Solutions

Nexis

Monitor, clean and manage from one window.

A system optimizer, monitor and manager for Linux and macOS. Open source under GPL-3.0 — the full source is public, and S4 Solutions maintains it.

  • A real-time dashboard for CPU, memory, disk, GPU and network.
  • Clean caches, logs and crash reports, on demand or on a schedule.
  • GPL-3.0, with the full source on GitHub.
Download Nexis About Nexis →
The Nexis dashboard: CPU, memory, GPU and battery cards with live charts, disk usage, network speeds and a health score.

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