Stop re-running gate stages whose inputs did not change

Stop re-running gate stages whose inputs did not change

The gate ran all fifteen stages every time, so a one-line test fix rebuilt
releases, re-ran the asset suite, and re-proved the staging infrastructure —
about forty minutes to learn one thing. Four runs died that way today on
mistakes that took seconds to fix.

Each stage now declares the paths it reads, and its key is Git's own tree
hashes for those paths plus the lockfile and the configuration, which every
stage depends on. A stage is reused only when it has already passed on
exactly those inputs. Recorded after it passes, so a failure is never
reused, and --force ignores the cache entirely.

Conservative by construction: a stage with no declared inputs gets the whole
worktree and never reuses. Adding a path to the list is always safe;
removing one is what could let a stage be reused when it should have run.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KnhfrafYx5ZGaMbzZEJQ2d

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01KnhfrafYx5ZGaMbzZEJQ2d

Deploy story

What this commit did to the running system — joined from the forge receipt chain, the part a commit page elsewhere cannot show.

pushed: by user · WAL seq 404 · 2026-08-25T15:37:41.764905Z

Changed files

modified ops/ci/gate.sh

Diff

1 file changed, +53 -0

98	98
99	99		`trap cleanup EXIT INT TERM`
100	100
	101	+	`# A stage's inputs, as paths. A stage is re-run when any of them changes and`
	102	+	`# reused when none of them has, so a test-only edit stops rebuilding releases`
	103	+	`# and re-running the asset suite. Everything depends on the lockfile and the`
	104	+	`# configuration, so those are added to every stage rather than listed here.`
	105	+	`#`
	106	+	`# The rule for editing this list is one-directional: adding a path is always`
	107	+	`# safe, and removing one can make the gate reuse a stage that should have run.`
	108	+	`# A stage whose inputs are not listed gets the whole worktree and therefore`
	109	+	`# never reuses, which is the safe default rather than an oversight.`
	110	+	`stage_inputs() {`
	111	+	`case $1 in`
	112	+	`compile \| production_compile) echo "lib" ;;`
	113	+	`precommit) echo "lib test priv assets ops" ;;`
	114	+	`enumeration_proofs) echo "lib test ops" ;;`
	115	+	`cluster \| direct_transaction \| relup_topology \| rolling_replacement) echo "lib test" ;;`
	116	+	`javascript) echo "assets" ;;`
	117	+	`relup \| version_chain \| interrupted_install) echo "lib priv assets ops" ;;`
	118	+	`contracts) echo "lib priv ops" ;;`
	119	+	`staging_infra) echo "ops" ;;`
	120	+	`release_smoke) echo "lib priv assets ops" ;;`
	121	+	`*) echo "." ;;`
	122	+	`esac`
	123	+	`}`
	124	+
	125	+	`# The identity of a stage's inputs: Git's own tree hashes, so a path that has`
	126	+	`# not changed hashes the same however it got there, and an uncommitted edit`
	127	+	`# hashes differently from the commit it sits on. The gate already refuses a`
	128	+	`# dirty worktree, so HEAD is the whole truth here.`
	129	+	`stage_key() {`
	130	+	`stage_name=$1`
	131	+	`{`
	132	+	`echo "$stage_name"`
	133	+	`for input_path in $(stage_inputs "$stage_name") mix.exs mix.lock config; do`
	134	+	`git -C "$repo_root" rev-parse "HEAD:$input_path" 2>/dev/null \|\|`
	135	+	`echo "absent:$input_path"`
	136	+	`done`
	137	+	`} \| shasum -a 256 \| cut -d" " -f1`
	138	+	`}`
	139	+
	140	+	`stage_cache_root="$git_common_dir/openagents/release-gate-stages"`
	141	+
101	142		`run_stage() {`
102	143		`stage_name=$1`
103	144		`shift`
104	145		`stage_log="$run_root/$stage_name.log"`
105	146		`stage_started=$(date +%s)`
106	147
	148	+	`cache_entry="$stage_cache_root/$stage_name.$(stage_key "$stage_name")"`
	149	+
	150	+	`if [ "$mode" != "--force" ] && [ -f "$cache_entry" ]; then`
	151	+	`echo "Reusing $stage_name (inputs unchanged since it last passed)"`
	152	+	`eval "${stage_name}_duration_seconds=$(cat "$cache_entry")"`
	153	+	`return 0`
	154	+	`fi`
	155	+
107	156		`echo "Running $stage_name"`
108	157
109	158		`set +e`


  stage_finished=$(date +%s)
  eval "${stage_name}_duration_seconds=$((stage_finished - stage_started))"

  # Recorded only after it passed, so a failure is never reused.
  mkdir -p "$stage_cache_root"
  eval "echo \$${stage_name}_duration_seconds" >"$cache_entry"
}

cd "$repo_root"

120	169
121	170		`stage_finished=$(date +%s)`
122	171		`eval "${stage_name}_duration_seconds=$((stage_finished - stage_started))"`
	172	+
	173	+	`# Recorded only after it passed, so a failure is never reused.`
	174	+	`mkdir -p "$stage_cache_root"`
	175	+	`eval "echo \$${stage_name}_duration_seconds" >"$cache_entry"`
123	176		`}`
124	177
125	178		`cd "$repo_root"`