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System 6 — Minimal Two-Platform

SoFi Invest and Coinbase. A deliberately small starter system with one brokerage and one on-ramp.

Who this is for

Readers who want the smallest possible coherent stack while they decide whether the framework fits.

System layers

  • On-ramp: Coinbase. Single regulated US exchange.
  • Yield venue: SoFi Invest. Commission-free brokerage with optional robo. Single venue; redundancy is intentionally absent at this stage.

Cadence

Quarterly review.

Why it works

Lowest possible friction. Practicing the cadence is the point.

What breaks it

Stopping here. A two-platform stack has no redundancy and should evolve into a three or four-platform system within a few months.