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Finance ETL · Part 8 of 8

Ask the group chat, get an answer from a laptop.

Free-text questions go from the bot to a local model on my Mac over Tailscale. The model reads the same views through eight read-only tools. Eight seconds warm, no tokens billed. Then: what comes next.

Scratch cut · 1:23 Split screen: Signal on the phone, Hermes gateway log on the Mac, MCP server log on the VM. The question travels, the tools fire, the answer lands. Demo data, scratch voice, real pipeline. The live recording takes over once it is shot.

The path

Signal group -> bot (VM) -> /v1/chat/completions over Tailscale -> Hermes gateway (Mac) -> Ollama
                 ^                                                     |
                 +---- finance MCP server (VM, 8 read-only tools) <----+

How it is locked down

What the measurements said

Gemma 4 26B-A4B answered an end-to-end finance question in 22 seconds cold and 8 seconds warm. A dense 32B model took 109 seconds, long enough to forget what you asked. The tool schemas make every prompt around 15k tokens, so prefill speed decides the experience, and the mixture-of-experts model wins on prefill.

The request path: a question leaves the phone, the laptop reads the data, and the answer comes back.

What comes next

Audio · 3 minWhat I would do differently
Scratch narration Type ids as text, alert from day one, start with Signal, and publish the build log while building, not after.
A phone labeled Signal, three speech bubbles, a grid of eight read-only tools, and a laptop labeled Hermes on the Mac.
Plate VIII · Asking it
Free to borrow for your feed · Square edition

Fin.

Eight parts. One small box. A family that asks the money questions out loud.

The master diagram: the eight stages of the pipeline on one card.

Begin again at part 1

Where you are: from an empty VM to a family chat that answers questions about the money. That is the whole build. Thanks for reading all eight.

Previous · Acting on itThat is all eight · See what ships next

Write to me

A laptop answered the family chat. What would yours answer?

Fractional CTO and CFO engagements start with a short call. No deck required, no pitch either. Bring the number you do not trust.

Tell me what is stuck