In this long sought after premium newsletter:

• Part 1 (this email):
  • A brief review of 2025 for the blog (2 minute read)
  • Some personal notes on ZFS mirroring (3 minute read)
  • Book recommendation: Vitön by Uusma (1 minute read)
• Part 2 (in your inbox tomorrow):
  • Pathfinding using multi-criteria shortest path (25 minute read)
• Part 3 (in your inbox two days from now):
  • Forecasts for the ACX 2026 prediction contest (35 minute read)

I suspect the readership will be split down the middle as to whether they find the pathfinding tutorial or the forecast rationales more interesting, but I had fun writing both.

The reason this premium newsletter is split into three parts is that Buttondown (which I use for sending these newsletters) helpfully informs me that if I sent it in one email, this newsletter would be 3× longer than Gmail accepts, which would harm deliverability.