https://www.toltec.io/engineering-notes.html Engineering notes from Toltec Systems: lessons from three decades of infrastructure, applied to AI, security and software. en-gb Sun, 04 Oct 2026 09:00:00 +0100 https://www.toltec.io/note-prove-parity.htmlhttps://www.toltec.io/note-prove-parity.htmlSun, 04 Oct 2026 09:00:00 +0100SoftwareBefore rebuilding a legacy system, capture what it actually does as tests, then replace it in slices behind a facade. Where AI helps, and where it does not. https://www.toltec.io/note-raid-to-retrieval.htmlhttps://www.toltec.io/note-raid-to-retrieval.htmlFri, 25 Sep 2026 09:00:00 +0100AI engineeringDisk arrays and AI retrieval fail in the same quiet way, reporting success while returning the wrong thing. What storage teaches about trustworthy retrieval. https://www.toltec.io/note-netware-agent-permissions.htmlhttps://www.toltec.io/note-netware-agent-permissions.htmlFri, 25 Sep 2026 09:00:00 +0100SecurityEffective rights on a 1990s NetWare server and an AI agent's permissions in Microsoft 365 are the same problem. How to work out what an agent can reach. https://www.toltec.io/note-capacity-planning.htmlhttps://www.toltec.io/note-capacity-planning.htmlFri, 25 Sep 2026 09:00:00 +0100InfrastructureN+1 thinking, headroom and graceful degradation kept virtual clusters running. The same discipline keeps AI systems fast and affordable under load. https://www.toltec.io/note-dr-testing.htmlhttps://www.toltec.io/note-dr-testing.htmlWed, 23 Sep 2026 09:00:00 +0100InfrastructureA disaster recovery test should prove five things with a stopwatch running: the data, the order, the access, the time and the people. How to test each one. https://www.toltec.io/note-ai-agent-access.htmlhttps://www.toltec.io/note-ai-agent-access.htmlWed, 23 Sep 2026 09:00:00 +0100AI engineeringGiving AI agents in Microsoft 365 exactly the access they need: separate identities, delegated access, scoped permissions, approvals and an off switch.