rustfmt on every edit, clippy before every commit touching Rust

A Claude Code hook formats each .rs file as it is edited, and the pre-commit
hook runs clippy as well as the format check. Clippy only checks, so with the
line-tables profile it takes under a minute (57 s after a change) at load 8.
rust-analyzer, which gave the same errors as clippy for 2.8 GB of memory, is
no longer used.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

.claude/settings.json

@@ -5,5 +5,18 @@
       "Bash(env)",
       "mcp__outline__read_document"
     ]
+  },
+  "hooks": {
+    "PostToolUse": [
+      {
+        "matcher": "Edit|Write|MultiEdit",
+        "hooks": [
+          {
+            "type": "command",
+            "command": "f=$(jq -r '.tool_input.file_path // empty'); case \"$f\" in *.rs) rustfmt --edition 2024 \"$f\" 2>/dev/null || true;; esac"
+          }
+        ]
+      }
+    ]
   }
 }

.githooks/pre-commit

@@ -1,7 +1,13 @@
 #!/bin/sh
-# Refuses a commit whose Rust is not as rustfmt writes it. Clippy is left to the checks before a
-# push (CLAUDE.md, Tests): it is a build, and Tower's builds go one at a time.
+# Refuses a commit whose Rust is not as rustfmt writes it, or that clippy warns about. Clippy only
+# checks and never links, so it is light beside a test build (CLAUDE.md, Tests); with the line-tables
+# profile it takes about a minute after a change and seconds otherwise.
 git diff --cached --name-only --diff-filter=ACM | grep -q '\.rs$' || exit 0
-cargo fmt --all --check >/dev/null 2>&1 && exit 0
-echo "pre-commit: the Rust is not formatted; run cargo fmt --all" >&2
-exit 1
+if ! cargo fmt --all --check >/dev/null 2>&1; then
+	echo "pre-commit: the Rust is not formatted; run cargo fmt --all" >&2
+	exit 1
+fi
+if ! cargo clippy --workspace --all-targets -q -- -D warnings; then
+	echo "pre-commit: clippy has warnings; fix them, or allow one where it is wrong, with a comment saying why" >&2
+	exit 1
+fi

CLAUDE.md

@@ -209,8 +209,9 @@ session was stopped. So:
   line tables and dependencies no debug info; keep it that way, and look at `MemAvailable` beside
   the load.
 
-The Rust is formatted by rustfmt (`rustfmt.toml`) and kept free of clippy's warnings. A clone
-turns on the hook once: `git config core.hooksPath .githooks`; and `git config blame.ignoreRevsFile
+The Rust is formatted by rustfmt (`rustfmt.toml`) and kept free of clippy's warnings. Claude Code
+formats each `.rs` file it edits (a hook in `.claude/settings.json`), and the pre-commit hook refuses
+a commit touching Rust that is unformatted or has a clippy warning. A clone turns on the hook once: `git config core.hooksPath .githooks`; and `git config blame.ignoreRevsFile
 .git-blame-ignore-revs` keeps blame past the commit that first formatted everything. A clippy
 suggestion is not always the same code: on adopting it, `fold(false, |any, id| remove(id) || any)`
 was offered as `any(...)`, which stops at the first and would have removed one feed of many. A lint