Elixir Iron Review

Iron Law review

Check portal/ Elixir against the Iron Laws in portal/AGENTS.md. The custom Credo checks (Emisar.Checks.*) cover the mechanical subset; this skill adds the judgment laws — including IL-15 and IL-16, whose safety depends on where a value came from, which a static check deliberately can't decide. Default scope: the working tree (git diff + untracked). A path or git ref narrows it.

Read-only by default. A fix request or --fix authorizes repairs within its scope. Gather evidence for judgment findings before changing behavior; ask only for a material decision or missing authority.

Step 1 — mechanical checks (Credo)

Use existing gate/Credo evidence when it covers the unchanged reviewed tree; otherwise run focused Credo on changed Elixir files. Report findings during a review; repair them only when fixes are authorized. The final Portal gate still includes full Credo. Details: portal/.agent/kb/rules/elixir-layered-contexts.md section Enforcement.

Step 2 — judgment checks (read the changed bodies)

For each changed context / query / changeset / authorizer / LiveView / MCP / controller file, read it and check:

• IL-3 — every public context fn takes %Subject{} as the last required arg and calls ensure_has_permissions/2 before any DB call. (Internal §1.4 helpers are exempt — confirm they're truly internal and unexposed.)
• IL-4 — Authorizer.for_subject(query, subject) sits immediately before every Repo.fetch/list/fetch_and_update in a context.
• IL-5 — public reads/writes return tagged tuples; no bare struct/nil.
• IL-9 — authorizers expose build(Schema, :verb) accessors, clause all roles, and the new authorizer is in auth/permissions.ex's @authorizers.
• IL-10 — Subject-gated context reads route preloads through Query preloads/0. An internal, no-Subject, already-authorized path holding a struct may use Repo.preload/2 for its parent association (post-commit email helpers or the runner-register billing check). Confirm that distinction before reporting a finding.
• IL-13 — recurrent jobs derive work from durable rows, keep each tick idempotent, and stay safe if a previous tick partially completed.
• IL-14 — String.to_atom/1 only on code literals / bounded sets; never on request params, runner output, or MCP/LLM input (atom-table DoS). Trace the arg to its source before clearing it.
• IL-16 — raw/1 only on app-generated / known-safe HTML (server-rendered QR SVG, sanitized markdown); never on runner output, runbook, or pack text (stored XSS). Confirm the source.
• IL-15 — every LiveView handle_event / MCP action / controller action that mutates passes the subject into a context call (no trusting mount/connect).
• IL-17 — long-lived processes are under a supervisor (no bare start_link).
• IL-18 — LiveView: no unconditional Repo/context read in mount (assign_async or connected? + cache); stream/3 for lists that can grow; connected?(socket) guard before subscribe; no assign_new for per-mount values.
• IL-11 — no shim/flag/deprecated-kept/corrective-migration-on-unshipped.
• IL-20 — a done local change has green ./run gate portal --changed output; a pushed or release-ready change has green ./run gate portal output.

Step 3 — report

One block per finding, ordered by law number, then severity:

IL-4 · BLOCKER · lib/emisar/widgets.ex:42
  list_widgets/2 calls Repo.list without Authorizer.for_subject above it — cross-account leak.
  Fix: pipe `|> Authorizer.for_subject(subject)` before `|> Repo.list(...)`.

Lead with a one-line verdict (N blockers, M suggestions). If clean, say so in one line — don't pad. Findings that need a human call (is this list large enough to need a stream?) are SUGGESTIONS with the question stated, not BLOCKERS.

Fix scope

Trace return contracts and data provenance before repairing a finding. Moving an inline query into its Query module can preserve behavior; replacing Repo.get with Repo.fetch changes the return shape, and changing a money field may require a production migration. Follow the actual caller and applied-migration contracts. For authorized security fixes, establish intended scope and test the denial path; do not require another confirmation merely because the finding involves judgment. Run focused checks after repair and the canonical final gate on the finished tree.