Pin the remaining developer tool installs (closes #68)

gofumpt and protoc-gen-go are tools of a separate Go module in bin/tools,
so `go tool` builds them from source checked against bin/tools/go.sum and
mfer's own module gains no dependencies. script/bootstrap downloads that
module, and unpacks protoc 33.4 into bin/protoc from its release archive
after checking the sha256 it holds for the platform. script/generate runs
that protoc with the pinned plugin, so mfer/mf.go and its go:generate line
go. script/prettier runs only the node_modules prettier, fails when it
differs from the package.json pin, finds the node bootstrap installed
through nvm by the version in .nvmrc, and runs prettier once. Comment and
package.json fixes.

Model: opus-5-5

script/bootstrap

@@ -13,11 +13,15 @@ set -eu
 ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
 
 # Pinned versions, 2026-07-06. Never "latest" or "lts"; exact versions.
-NODE_VERSION="22.17.0"
+# The node version is in .nvmrc, where script/prettier reads it too.
+NODE_VERSION="$(cat "$ROOT/.nvmrc")"
 NVM_VERSION="0.40.3"
 # sha256 of https://github.com/nvm-sh/nvm/archive/refs/tags/v0.40.3.tar.gz
 NVM_SHA256="5f4d6aaa04a177dc93c985e31dbc411ab6b8c6e1e21d8015dbc1372625fcd1d0"
 YARN_VERSION="1.22.22"
+# protoc v33.4, 2026-10-04, for script/generate. The sha256 of each
+# platform's release archive is in ensure_protoc.
+PROTOC_VERSION="33.4"
 
 PKGMGR=""
 SUDO=""
@@ -74,9 +78,11 @@ verify_sha256() {
     fi
 }
 
-# nvm is a bash script; run a command in a bash with nvm loaded
+# nvm is a bash script; run a command in a bash with nvm loaded.
+# --no-use: otherwise loading nvm here switches to the version .nvmrc
+# names, and fails silently while that version is not installed yet.
 nvm_sh() {
-    bash -c ". \"\$HOME/.nvm/nvm.sh\" && $*"
+    bash -c ". \"\$HOME/.nvm/nvm.sh\" --no-use && $*"
 }
 
 ensure_nvm() {
@@ -122,6 +128,48 @@ install_js_deps() {
     fi
 }
 
+# Unpack protoc's release archive for this platform into bin/protoc, after
+# checking the archive's sha256, unless bin/protoc already holds the pinned
+# version.
+ensure_protoc() {
+    dir="$ROOT/bin/protoc"
+    if [ "$("$dir/bin/protoc" --version 2>/dev/null)" = \
+        "libprotoc $PROTOC_VERSION" ]; then
+        return 0
+    fi
+    case "$(uname -s) $(uname -m)" in
+        "Linux x86_64")
+            platform="linux-x86_64"
+            sha256="c0040ea9aef08fdeb2c74ca609b18d5fdbfc44ea0042fcfbfb38860d35f7dd66"
+            ;;
+        "Linux aarch64" | "Linux arm64")
+            platform="linux-aarch_64"
+            sha256="15aa988f4a6090636525ec236a8e4b3aab41eef402751bd5bb2df6afd9b7b5a5"
+            ;;
+        "Darwin x86_64")
+            platform="osx-x86_64"
+            sha256="a49bec10d039e902d3b43e49938c42526f90011467609864fa6386ac4014da58"
+            ;;
+        "Darwin arm64")
+            platform="osx-aarch_64"
+            sha256="726297dcfed58592fd35620a5a6246ae020c39e88f3fd4cb1827df7bcf3dfcf1"
+            ;;
+        *)
+            echo "bootstrap: no protoc archive pinned for $(uname -s) $(uname -m)" >&2
+            exit 1
+            ;;
+    esac
+    if missing curl; then pkg_install curl curl curl curl; fi
+    if missing unzip; then pkg_install unzip unzip unzip unzip; fi
+    tmp="$(mktemp -d)"
+    curl -fsSL -o "$tmp/protoc.zip" \
+        "https://github.com/protocolbuffers/protobuf/releases/download/v${PROTOC_VERSION}/protoc-${PROTOC_VERSION}-${platform}.zip"
+    verify_sha256 "$tmp/protoc.zip" "$sha256"
+    rm -rf "$dir"
+    unzip -q "$tmp/protoc.zip" -d "$dir"
+    rm -rf "$tmp"
+}
+
 main() {
     cd "$ROOT"
 
@@ -132,8 +180,10 @@ main() {
     # ---- JS / docs repos ----
     # This is a Go repo, but node and yarn are required anyway: prettier
     # formats the Markdown and JSON, and script/fmt-check verifies it.
-    # The version is pinned by package.json/yarn.lock, whose integrity
-    # hashes --frozen-lockfile enforces.
+    # The version is pinned by package.json/yarn.lock: yarn checks every
+    # package it fetches against its yarn.lock integrity hash, and
+    # --frozen-lockfile fails instead of rewriting a yarn.lock that no
+    # longer matches package.json.
     ensure_node
     ensure_yarn
     install_js_deps
@@ -142,6 +192,10 @@ main() {
     if missing go; then pkg_install go golang go go; fi
     # No golangci-lint: script/lint runs it in Docker only.
     go mod download
+    # gofumpt and protoc-gen-go: bin/tools/go.mod pins them, and
+    # script/gofumpt and script/generate build them from there.
+    (cd "$ROOT/bin/tools" && go mod download)
+    ensure_protoc
 
     # ---- Python repos ----
     # if missing python3; then pkg_install python3 python3 python3 python3; fi

script/generate

@@ -4,26 +4,17 @@
 # regenerates mf.pb.go: it is committed, so building and checking need no
 # protoc. A test fails while mf.proto no longer matches the recorded hash.
 #
-# Needs exactly the protoc and protoc-gen-go versions named in the header of
-# the committed mf.pb.go (README.md says how to install them). Another
-# version writes a different mf.pb.go, so the script refuses to run.
+# Runs the protoc that script/bootstrap unpacks into bin/protoc, and the
+# protoc-gen-go that bin/tools/go.mod pins. Another version of either
+# writes a different mf.pb.go.
 set -eu
 
 ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
 
-# protoc 33.4 names itself v6.33.4 in the mf.pb.go header.
+# The protoc version script/bootstrap installs. protoc 33.4 names itself
+# v6.33.4 in the mf.pb.go header.
 PROTOC_VERSION="33.4"
-PROTOC_GEN_GO_VERSION="v1.36.11"
-
-# require_version <command> <its exact --version output>
-require_version() {
-    actual="$("$1" --version 2>/dev/null || true)"
-    if [ "$actual" != "$2" ]; then
-        echo "generate: needs $2 on PATH, found: ${actual:-none}" >&2
-        echo "  README.md says how to install it." >&2
-        exit 1
-    fi
-}
+PROTOC="$ROOT/bin/protoc/bin/protoc"
 
 # sha256 <file>: print "<hash>  <file>", with sha256sum, or with shasum
 # where there is no sha256sum.
@@ -39,16 +30,24 @@ sha256() {
 }
 
 main() {
+    # A bin/protoc left from before the pin moved fails here, until
+    # script/bootstrap replaces it.
+    actual="$("$PROTOC" --version 2>/dev/null || true)"
+    if [ "$actual" != "libprotoc $PROTOC_VERSION" ]; then
+        echo "generate: needs protoc $PROTOC_VERSION in bin/protoc," \
+            "found: ${actual:-none}; run script/bootstrap" >&2
+        exit 1
+    fi
+    # `go tool -n` builds protoc-gen-go from bin/tools and prints where the
+    # binary is, without running it.
+    plugin="$(cd "$ROOT/bin/tools" && go tool -n protoc-gen-go)"
+
     cd "$ROOT/mfer"
-    # `go install` puts protoc-gen-go in $(go env GOPATH)/bin, which is
-    # often not on PATH.
-    PATH="$PATH:$(go env GOPATH)/bin"
-    require_version protoc "libprotoc $PROTOC_VERSION"
-    require_version protoc-gen-go "protoc-gen-go $PROTOC_GEN_GO_VERSION"
     # Hashed before regenerating, so a missing hash tool stops the script
     # before it changes anything. Regenerating leaves mf.proto as it is.
     proto_hash="$(sha256 mf.proto)"
-    go generate .
+    "$PROTOC" --plugin=protoc-gen-go="$plugin" \
+        --go_out=paths=source_relative:. ./mf.proto
     echo "$proto_hash" >mf.proto.sha256
 }
 

script/gofumpt

@@ -10,10 +10,10 @@ set -eu
 
 ROOT="$(cd "$(dirname "$0")/.." && pwd -P)"
 
-# gofumpt v0.12.0, 2026-10-04. `go run` fetches and builds exactly this
-# version, so neither a developer machine nor the lint image needs
-# gofumpt installed.
-GOFUMPT="mvdan.cc/gofumpt@v0.12.0"
+# The gofumpt version is the one bin/tools/go.mod pins. `go tool` run in
+# bin/tools builds it from source checked against the hashes in
+# bin/tools/go.sum, so neither a developer machine nor the lint image needs
+# it installed.
 
 usage() {
     echo "usage: script/gofumpt --write|--check" >&2
@@ -22,15 +22,15 @@ usage() {
 
 main() {
     [ "$#" -eq 1 ] || usage
-    cd "$ROOT"
-    # Every Go file in the repo. gofumpt holds generated files, such as
-    # mfer/mf.pb.go, to gofmt's rules only.
+    cd "$ROOT/bin/tools"
+    # Every Go file in the repo, from $ROOT down. gofumpt holds generated
+    # files, such as mfer/mf.pb.go, to gofmt's rules only.
     case "$1" in
-        --write) go run "$GOFUMPT" -l -w . ;;
+        --write) go tool gofumpt -l -w "$ROOT" ;;
         --check)
             # Own line: a failing command inside `[ -n "$(...)" ]` does
             # not trip `set -e`, so a gofumpt that never ran would pass.
-            unformatted="$(go run "$GOFUMPT" -l .)"
+            unformatted="$(go tool gofumpt -l "$ROOT")"
             if [ -n "$unformatted" ]; then
                 echo "gofumpt: files need formatting (run make fmt):" >&2
                 echo "$unformatted" >&2

script/prettier

@@ -18,24 +18,9 @@ usage() {
     exit 2
 }
 
-# Prefer the version pinned by package.json/yarn.lock so that CI and
-# developer machines format identically. Fall back to a prettier on PATH,
-# but say so, because a different version formats differently.
-find_prettier() {
-    if [ -x "$ROOT/node_modules/.bin/prettier" ]; then
-        printf '%s\n' "$ROOT/node_modules/.bin/prettier"
-        return 0
-    fi
-    if command -v prettier >/dev/null 2>&1; then
-        echo "prettier: node_modules/.bin/prettier is absent; using the" \
-            "prettier on PATH, which may be a different version than the" \
-            "one pinned in package.json. Run script/bootstrap to install" \
-            "the pinned version." >&2
-        command -v prettier
-        return 0
-    fi
-    return 1
-}
+# Only the prettier yarn installed from yarn.lock, never one on PATH: a
+# different version formats differently.
+PRETTIER="$ROOT/node_modules/.bin/prettier"
 
 main() {
     [ "$#" -eq 1 ] || usage
@@ -46,10 +31,26 @@ main() {
 
     cd "$ROOT"
 
-    if ! prettier_bin="$(find_prettier)"; then
-        echo "prettier: not found." >&2
-        echo "  Install it with: script/bootstrap" >&2
-        echo "  (installs the version pinned in package.json/yarn.lock)" >&2
+    # Where there is no node on PATH, script/bootstrap installs the version
+    # .nvmrc names through nvm, which keeps it in this directory.
+    if ! command -v node >/dev/null 2>&1; then
+        PATH="$HOME/.nvm/versions/node/v$(cat .nvmrc)/bin:$PATH"
+    fi
+    if ! command -v node >/dev/null 2>&1; then
+        echo "prettier: node is missing; run script/bootstrap" >&2
+        exit 1
+    fi
+
+    # node_modules keeps the old prettier after package.json moves to a new
+    # one, until script/bootstrap runs again, so compare the two.
+    if ! installed="$("$PRETTIER" --version 2>/dev/null)"; then
+        echo "prettier: not installed; run script/bootstrap" >&2
+        exit 1
+    fi
+    pinned="$(node -p 'require("./package.json").devDependencies.prettier')"
+    if [ "$installed" != "$pinned" ]; then
+        echo "prettier: package.json pins $pinned but $installed is" \
+            "installed; run script/bootstrap" >&2
         exit 1
     fi
 
@@ -62,8 +63,7 @@ main() {
     # patterns always match at least one tracked file (README.md,
     # package.json), so an empty match means the glob broke, and prettier
     # erroring out is exactly what we want rather than a vacuous pass.
-    "$prettier_bin" "$mode" "**/*.md"
-    "$prettier_bin" "$mode" "**/*.json"
+    "$PRETTIER" "$mode" "**/*.md" "**/*.json"
 }
 
 main "$@"