Unix survives at the verb, not the binary

One tool that does one thing extremely well does not survive contact with a monorepo, and magus does not claim the lineage: a monorepo build tool has to understand several languages, every project in the tree, caching, scheduling, and what a change reaches. That is already many things. What survives the translation is the discipline, relocated to the verb. Each verb answers one question, deterministically, from declared sources, and stops. Output reads at a terminal and parses in a pipe (-o name, -o json, -o template=; the pipe is for people, and the agent guard routes an agent to -o instead, because a pipe replaces the exit status and a failing gate then reads as 0). A non-zero exit means what it has meant for fifty years. Everything magus draws degrades to plain text when there is no terminal to draw on, and the pinned band never takes the screen, the alternate buffer, or your scrollback. Composition happens where a monorepo needs it (in the graph, through ctx.needs), not by pretending the binary can be smaller than the problem.

The scope test governs what a verb may be, and the one-vocabulary rule (target, spell, charm, op, each named once and reused everywhere) keeps the command set predictable. That prevents the failure in both directions: claiming a minimalism the tool cannot carry, and the house dialect with no rule you can hold in your head, the one that makes users look things up forever and then teaches their agents the same confusion.

The discipline reaches the code too:

• A main package only wires. A command parses its flags, builds its dependencies, calls a package and prints the result. Logic that computes belongs in the package that owns its data, where a test and a second caller can reach it.
• One file until it is long. A concept stays in one file until that file passes 1500 lines; only then does R_<topic>.go earn a place beside R.go. A platform build, generated output and a test are their own files at any size.

Enforced by

• The scope test, applied in review to every new verb.
• The main-logic conformance metric fails a main-package function that computes without calling another workspace package; the ratchet (hack/policy/conformance.jsonl) lists the ones that predate it.
• The file-split conformance metric fails a concept sibling that would fit in its root at 1500 lines or fewer, and moves with the file-lines ceiling.
• The agent guard denies piping magus output and names the -o form instead.

Good

Ask the verb for the shape you want; the exit status stays the verb's.

magus affected ci --plan -o json
magus ls -o name

Bad

magus run test . | tail -n 20

tail exits 0 whatever the tests did, so a failing gate reads as a pass in CI and to an agent.

See also

• Scope
• The knobs
• Human-first is the AI integration