From 4b3adf10b699e97605e9798409f91745422b5fb3 Mon Sep 17 00:00:00 2001
From: Will Jones <willjones127@gmail.com>
Date: Mon, 22 Jun 2026 10:52:29 -0700
Subject: [PATCH 1/2] ci: enforce PMC vote on format-spec changes via CI gate
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Format-specification changes (the `.proto` definitions and `docs/src/format/**`)
require 3 binding +1 votes from PMC members, but nothing structurally enforced
it — the requirement was only a reminder comment, caught socially if at all.

This adds a CI gate that blocks merging a format-spec change until it has the
required votes. A touched PR is labelled `format-change` and the gate publishes
a `format-spec-vote` commit status that stays red until:

- 3 PMC members have approved the PR (excluding the author), counted only on the
  latest commit so new pushes invalidate stale approvals;
- no PMC member has an outstanding "Request changes" review (a veto); and
- the 1-week voting period (from when the label was first applied) has elapsed.

The gate posts a live tally comment and runs on PR events, review events, and an
8-hourly cron (so the voting-period clock is re-checked even when no event
fires). It uses pull_request_target to label/status fork PRs but never checks
out or runs PR code. A PMC member can waive a trivial edit by removing the
`format-change` label.

The PMC roster moves to `docs/src/community/pmc.yaml` as the source of truth;
`ci/sync_pmc_docs.py` regenerates the table in pmc.md (checked in docs-check),
and the gate reads the roster from the base checkout so a PR cannot enlarge the
electorate. The old reminder-only job is removed.

To activate, add `format-spec-vote` as a required status check on protected
branches.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
---
 .github/workflows/ci-scripts.yml       |  36 +++
 .github/workflows/docs-check.yml       |   5 +
 .github/workflows/format-vote-gate.yml |  64 +++++
 .github/workflows/pr-title.yml         |  63 -----
 ci/format_vote_gate.js                 | 311 +++++++++++++++++++++++++
 ci/format_vote_gate.test.js            |  92 ++++++++
 ci/sync_pmc_docs.py                    | 100 ++++++++
 docs/src/community/pmc.md              |   6 +-
 docs/src/community/pmc.yaml            |  90 +++++++
 docs/src/community/voting.md           |  31 ++-
 10 files changed, 733 insertions(+), 65 deletions(-)
 create mode 100644 .github/workflows/ci-scripts.yml
 create mode 100644 .github/workflows/format-vote-gate.yml
 create mode 100644 ci/format_vote_gate.js
 create mode 100644 ci/format_vote_gate.test.js
 create mode 100644 ci/sync_pmc_docs.py
 create mode 100644 docs/src/community/pmc.yaml

diff --git a/.github/workflows/ci-scripts.yml b/.github/workflows/ci-scripts.yml
new file mode 100644
index 00000000000..ab7bb62cc40
--- /dev/null
+++ b/.github/workflows/ci-scripts.yml
@@ -0,0 +1,36 @@
+name: CI scripts
+
+# Tests for helper scripts under ci/ that aren't covered by the language test
+# suites (e.g. the format-spec vote gate logic).
+
+on:
+  push:
+    branches:
+      - main
+      - release/**
+  pull_request:
+    branches:
+      - main
+      - release/**
+    paths:
+      - ci/format_vote_gate.js
+      - ci/format_vote_gate.test.js
+      - .github/workflows/format-vote-gate.yml
+      - .github/workflows/ci-scripts.yml
+
+permissions:
+  contents: read
+
+jobs:
+  format-vote-gate:
+    name: Format vote gate unit tests
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4
+      - name: Set up Node
+        uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4
+        with:
+          node-version: "20"
+      - name: Run tests
+        run: node --test ci/format_vote_gate.test.js
diff --git a/.github/workflows/docs-check.yml b/.github/workflows/docs-check.yml
index 2eda3de66b4..15576e42f22 100644
--- a/.github/workflows/docs-check.yml
+++ b/.github/workflows/docs-check.yml
@@ -11,6 +11,7 @@ on:
       - release/**
     paths:
       - docs/**
+      - ci/sync_pmc_docs.py
       - .github/workflows/docs-check.yml
 
 permissions:
@@ -41,3 +42,7 @@ jobs:
         working-directory: docs
         run: |
           uv run mkdocs-linkcheck src
+      - name: Check PMC roster table is in sync with pmc.yaml
+        working-directory: docs
+        run: |
+          uv run python ../ci/sync_pmc_docs.py --check
diff --git a/.github/workflows/format-vote-gate.yml b/.github/workflows/format-vote-gate.yml
new file mode 100644
index 00000000000..ec32568d3bd
--- /dev/null
+++ b/.github/workflows/format-vote-gate.yml
@@ -0,0 +1,64 @@
+name: Format spec vote gate
+
+# Structurally enforces the PMC vote required for Lance format-specification
+# changes (see https://lance.org/community/voting/). A PR that touches the
+# format spec (`protos/**/*.proto`, `docs/src/format/**`) is labelled
+# `format-change` and cannot merge until it has 3 binding +1 votes from PMC
+# members (PR approvals, excluding the author), has no outstanding veto (a PMC
+# "Request changes" review), and the 1-week voting period has elapsed.
+#
+# The gate publishes its verdict as the `format-spec-vote` commit status on the
+# PR head. To make it a merge blocker, an org admin must add `format-spec-vote`
+# as a required status check in the branch protection rules for `main` (and any
+# release branches). The status is posted on *every* PR — success immediately
+# for non-format PRs — so a required check is never left pending forever.
+#
+# A PMC member may exempt a trivial edit (typo, wording, formatting) by removing
+# the `format-change` label; the gate respects that and will not re-add it.
+#
+# Uses pull_request_target so the token can label PRs and post statuses on
+# fork-based PRs. It never checks out or executes PR code: it reads the trusted
+# base checkout (for the PMC roster) and queries the API only.
+
+on:
+  pull_request_target:
+    types: [opened, reopened, synchronize, labeled, unlabeled]
+  pull_request_review:
+    types: [submitted, edited, dismissed]
+  schedule:
+    # Re-evaluate open format-change PRs so the voting-period clock is re-checked
+    # even when no PR event fires (e.g. the 1-week period elapses days after the
+    # third approval lands).
+    - cron: "0 */8 * * *"
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.run_id }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read
+  pull-requests: write
+  issues: write
+  statuses: write
+
+jobs:
+  gate:
+    name: Evaluate format spec vote
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout base
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4
+      - name: Set up Node
+        uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4
+        with:
+          node-version: "20"
+      - name: Install js-yaml
+        run: npm install --no-save js-yaml@4
+      - name: Evaluate vote
+        uses: actions/github-script@f28e40c7f34bde8b3046d885e986cb6290c5673b # v7
+        with:
+          script: |
+            const path = require('path');
+            // Loaded from the trusted base checkout, never from PR code.
+            const gate = require(path.join(process.env.GITHUB_WORKSPACE, 'ci', 'format_vote_gate.js'));
+            await gate.run({ github, context, core });
diff --git a/.github/workflows/pr-title.yml b/.github/workflows/pr-title.yml
index a9d339e36ce..51c899f56a3 100644
--- a/.github/workflows/pr-title.yml
+++ b/.github/workflows/pr-title.yml
@@ -22,69 +22,6 @@ jobs:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
           fail_on_error: true
-  format-vote-reminder:
-    permissions:
-      pull-requests: write
-    name: Remind about format spec vote
-    runs-on: ubuntu-latest
-    # Comments on PRs that touch the Lance format specification (*.proto files
-    # and docs/src/format/**) to remind the author that substantive format
-    # changes require a PMC vote. Re-checks the full PR diff on every push, so a
-    # format change introduced by a later commit is still caught; a hidden
-    # marker keeps it to at most one comment.
-    steps:
-      - uses: actions/github-script@f28e40c7f34bde8b3046d885e986cb6290c5673b # v7
-        with:
-          script: |
-            const { owner, repo } = context.repo;
-            const prNumber = context.payload.pull_request.number;
-            const MARKER = '<!-- format-change-vote-reminder -->';
-
-            // The Lance format specification is the proto definitions plus the
-            // spec docs. Changes to either require a PMC vote.
-            const isFormatFile = (path) =>
-              path.endsWith('.proto') || path.startsWith('docs/src/format/');
-
-            const files = await github.paginate(github.rest.pulls.listFiles, {
-              owner, repo, pull_number: prNumber, per_page: 100,
-            });
-            const formatFiles = files.map((f) => f.filename).filter(isFormatFile);
-            if (formatFiles.length === 0) {
-              core.info('No format specification files changed; nothing to do.');
-              return;
-            }
-
-            // Best effort to comment only once: skip if our marker is present.
-            const comments = await github.paginate(github.rest.issues.listComments, {
-              owner, repo, issue_number: prNumber, per_page: 100,
-            });
-            if (comments.some((c) => c.body && c.body.includes(MARKER))) {
-              core.info('Reminder already posted; skipping.');
-              return;
-            }
-
-            const body = [
-              MARKER,
-              '> [!IMPORTANT]',
-              '> **This PR touches the Lance format specification.**',
-              '>',
-              '> Substantive changes to the format specification — the `.proto` definitions',
-              '> and the spec docs under `docs/src/format/` — require a PMC vote before merge.',
-              '> Minor edits such as typo fixes, wording, or formatting are excluded; use your',
-              '> judgment.',
-              '>',
-              '> If this is a meaningful format change:',
-              '> - Start a vote following the [Lance community voting process](https://lance.org/community/voting/).',
-              '>   Format specification modifications need **3 binding +1 votes** (excluding the',
-              '>   proposer), held on GitHub Discussions, with a minimum voting period of **1 week**.',
-              '> - Once the vote passes, **link the completed vote in this PR**. It should not be',
-              '>   merged until the vote is linked.',
-            ].join('\n');
-
-            await github.rest.issues.createComment({
-              owner, repo, issue_number: prNumber, body,
-            });
-            core.info(`Posted format vote reminder (changed: ${formatFiles.join(', ')}).`);
   commitlint:
     permissions:
       pull-requests: write
diff --git a/ci/format_vote_gate.js b/ci/format_vote_gate.js
new file mode 100644
index 00000000000..bb5208fe8ca
--- /dev/null
+++ b/ci/format_vote_gate.js
@@ -0,0 +1,311 @@
+// Logic for the format-specification vote gate
+// (`.github/workflows/format-vote-gate.yml`). Extracted into a module so the
+// vote-counting rules can be unit tested (see `format_vote_gate.test.js`); the
+// workflow loads it from the trusted base checkout and calls `run`.
+
+const fs = require("fs");
+const path = require("path");
+
+const STATUS_CONTEXT = "format-spec-vote";
+const LABEL = "format-change";
+const COMMENT_MARKER = "<!-- format-spec-vote-status -->";
+const REQUIRED_APPROVALS = 3;
+const PERIOD_DAYS = 7;
+const PERIOD_MS = PERIOD_DAYS * 24 * 60 * 60 * 1000;
+const VOTING_URL = "https://lance.org/community/voting/";
+const DAY_MS = 24 * 60 * 60 * 1000;
+
+// The Lance format specification is the proto definitions and the spec docs.
+// Changes to either require a PMC vote.
+function isFormatFile(p) {
+  return (
+    (p.endsWith(".proto") && p.startsWith("protos/")) ||
+    p.startsWith("docs/src/format/")
+  );
+}
+
+// Each PMC member's current stance is their most recent non-comment review.
+// Approvals are only counted on the head commit (stale approvals from earlier
+// commits do not count toward the bar); a "changes requested" review is a veto
+// and blocks regardless of commit until withdrawn. The PR author never counts,
+// even if they are on the PMC.
+function tallyReviews(reviews, headSha, author, isPmc) {
+  const latest = new Map();
+  for (const r of reviews) {
+    const login = r.user && r.user.login;
+    if (!login || !isPmc(login) || login === author) continue;
+    if (!["APPROVED", "CHANGES_REQUESTED", "DISMISSED"].includes(r.state)) {
+      continue;
+    }
+    latest.set(login.toLowerCase(), {
+      login,
+      state: r.state,
+      commitId: r.commit_id,
+    });
+  }
+  const approvals = [];
+  const staleApprovals = [];
+  const vetoes = [];
+  for (const v of latest.values()) {
+    if (v.state === "APPROVED") {
+      (v.commitId === headSha ? approvals : staleApprovals).push(v.login);
+    } else if (v.state === "CHANGES_REQUESTED") {
+      vetoes.push(v.login);
+    }
+  }
+  return { approvals, staleApprovals, vetoes };
+}
+
+// Pure decision: which blocking condition (if any) applies, in priority order.
+function decideVerdict({ vetoCount, approvalCount, periodElapsed, required }) {
+  if (vetoCount > 0) return "veto";
+  if (approvalCount < required) return "insufficient";
+  if (!periodElapsed) return "waiting_period";
+  return "pass";
+}
+
+const fmtList = (xs) => (xs.length ? xs.map((u) => `@${u}`).join(", ") : "none");
+
+function loadPmc(workspace) {
+  const yaml = require(path.join(workspace, "node_modules", "js-yaml"));
+  const rosterPath = path.join(workspace, "docs", "src", "community", "pmc.yaml");
+  const roster = yaml.load(fs.readFileSync(rosterPath, "utf8"));
+  return new Set(roster.members.map((m) => m.handle.toLowerCase()));
+}
+
+async function run({ github, context, core }) {
+  const { owner, repo } = context.repo;
+  const workspace = process.env.GITHUB_WORKSPACE;
+  const pmc = loadPmc(workspace);
+  const isPmc = (login) => login != null && pmc.has(login.toLowerCase());
+  const runUrl = `${context.serverUrl}/${owner}/${repo}/actions/runs/${context.runId}`;
+
+  async function setStatus(sha, state, description) {
+    await github.rest.repos.createCommitStatus({
+      owner,
+      repo,
+      sha,
+      state,
+      context: STATUS_CONTEXT,
+      description: description.slice(0, 140),
+      target_url: runUrl,
+    });
+  }
+
+  async function upsertComment(prNumber, body) {
+    const full = `${COMMENT_MARKER}\n${body}`;
+    const comments = await github.paginate(github.rest.issues.listComments, {
+      owner,
+      repo,
+      issue_number: prNumber,
+      per_page: 100,
+    });
+    const existing = comments.find((c) => c.body && c.body.includes(COMMENT_MARKER));
+    if (existing) {
+      if (existing.body !== full) {
+        await github.rest.issues.updateComment({
+          owner,
+          repo,
+          comment_id: existing.id,
+          body: full,
+        });
+      }
+    } else {
+      await github.rest.issues.createComment({
+        owner,
+        repo,
+        issue_number: prNumber,
+        body: full,
+      });
+    }
+  }
+
+  // Returns { firstAddedAt, removedByPmc } for LABEL on this PR, from the
+  // timeline: when the label was first applied (the vote-period anchor) and
+  // whether a PMC member deliberately removed it (a trivial-edit waiver).
+  async function labelHistory(prNumber) {
+    const events = await github.paginate(
+      github.rest.issues.listEventsForTimeline,
+      { owner, repo, issue_number: prNumber, per_page: 100 },
+    );
+    let firstAddedAt = null;
+    let removedByPmc = false;
+    for (const e of events) {
+      if (!e.label || e.label.name !== LABEL) continue;
+      if (e.event === "labeled" && !firstAddedAt) {
+        firstAddedAt = e.created_at;
+      } else if (e.event === "unlabeled" && isPmc(e.actor && e.actor.login)) {
+        removedByPmc = true;
+      }
+    }
+    return { firstAddedAt, removedByPmc };
+  }
+
+  async function evaluate(prNumber) {
+    const { data: pr } = await github.rest.pulls.get({
+      owner,
+      repo,
+      pull_number: prNumber,
+    });
+    if (pr.state !== "open") {
+      core.info(`PR #${prNumber} is ${pr.state}; skipping.`);
+      return;
+    }
+    const headSha = pr.head.sha;
+    const author = pr.user.login;
+
+    const files = await github.paginate(github.rest.pulls.listFiles, {
+      owner,
+      repo,
+      pull_number: prNumber,
+      per_page: 100,
+    });
+    const touchesFormat = files.map((f) => f.filename).some(isFormatFile);
+
+    let hasLabel = pr.labels.some((l) => l.name === LABEL);
+    const { firstAddedAt, removedByPmc } = await labelHistory(prNumber);
+
+    // Auto-apply the label, unless a PMC member deliberately removed it.
+    if (touchesFormat && !hasLabel && !removedByPmc) {
+      await github.rest.issues.addLabels({
+        owner,
+        repo,
+        issue_number: prNumber,
+        labels: [LABEL],
+      });
+      hasLabel = true;
+    }
+
+    if (!hasLabel) {
+      await setStatus(
+        headSha,
+        "success",
+        removedByPmc
+          ? "Format-spec vote waived by a PMC member."
+          : "No format-spec change; vote not required.",
+      );
+      if (removedByPmc) {
+        await upsertComment(
+          prNumber,
+          `> [!NOTE]\n> A PMC member removed the \`${LABEL}\` label, ` +
+            `waiving the format-spec vote for this PR (trivial edit).`,
+        );
+      }
+      core.info(`PR #${prNumber}: no vote required.`);
+      return;
+    }
+
+    const reviews = await github.paginate(github.rest.pulls.listReviews, {
+      owner,
+      repo,
+      pull_number: prNumber,
+      per_page: 100,
+    });
+    const { approvals, staleApprovals, vetoes } = tallyReviews(
+      reviews,
+      headSha,
+      author,
+      isPmc,
+    );
+
+    const now = new Date();
+    const voteStart = firstAddedAt ? new Date(firstAddedAt) : now;
+    const periodEnds = new Date(voteStart.getTime() + PERIOD_MS);
+    const periodElapsed = now >= periodEnds;
+    const verdict = decideVerdict({
+      vetoCount: vetoes.length,
+      approvalCount: approvals.length,
+      periodElapsed,
+      required: REQUIRED_APPROVALS,
+    });
+
+    const endDate = periodEnds.toISOString().slice(0, 10);
+    let state, summary, headline;
+    if (verdict === "veto") {
+      state = "failure";
+      summary = `Vetoed by ${vetoes.length} PMC member(s).`;
+      headline = `❌ Blocked — vetoed by ${fmtList(vetoes)}`;
+    } else if (verdict === "insufficient") {
+      state = "failure";
+      summary = `${approvals.length}/${REQUIRED_APPROVALS} PMC approvals on this commit.`;
+      headline = `❌ Blocked — ${approvals.length} of ${REQUIRED_APPROVALS} required approvals`;
+    } else if (verdict === "waiting_period") {
+      state = "failure";
+      summary = `Approved; voting period ends ${endDate}.`;
+      headline =
+        `⏳ Approvals met (${approvals.length}/${REQUIRED_APPROVALS}); ` +
+        `voting period ends ${endDate}`;
+    } else {
+      state = "success";
+      summary = `Passed — ${approvals.length} PMC approvals, period elapsed.`;
+      headline = `✅ Vote passed — ${approvals.length} PMC approvals, voting period elapsed`;
+    }
+
+    const daysLeft = Math.max(0, Math.ceil((periodEnds.getTime() - now.getTime()) / DAY_MS));
+    const periodCell = periodElapsed
+      ? `elapsed (ended ${endDate})`
+      : `ends ${endDate} (${daysLeft} day(s) left)`;
+    const approvalCell =
+      `${fmtList(approvals)} (${approvals.length}/${REQUIRED_APPROVALS})` +
+      (staleApprovals.length
+        ? ` — stale, re-approve needed: ${fmtList(staleApprovals)}`
+        : "");
+
+    const body = [
+      "> [!IMPORTANT]",
+      "> ## Format specification vote",
+      "",
+      "This PR modifies the Lance format specification, so it requires " +
+        `**${REQUIRED_APPROVALS} binding +1 votes from PMC members** ` +
+        "(excluding the proposer) and a minimum " +
+        `**${PERIOD_DAYS}-day** voting period before it can merge. ` +
+        "Vote by approving this PR (+1) or requesting changes (−1, a veto). " +
+        `See the [voting process](${VOTING_URL}).`,
+      "",
+      `**Status: ${headline}**`,
+      "",
+      "| | |",
+      "|---|---|",
+      `| Approvals (this commit) | ${approvalCell} |`,
+      `| Vetoes | ${fmtList(vetoes)} |`,
+      `| Voting period | ${periodCell} |`,
+      "",
+      "<sub>Updated automatically by the format-spec vote gate. A PMC member " +
+        `may remove the \`${LABEL}\` label to waive the vote for a trivial edit ` +
+        "(typo, wording, formatting).</sub>",
+    ].join("\n");
+
+    await setStatus(headSha, state, summary);
+    await upsertComment(prNumber, body);
+    core.info(`PR #${prNumber}: ${summary}`);
+  }
+
+  if (context.eventName === "schedule") {
+    const issues = await github.paginate(github.rest.issues.listForRepo, {
+      owner,
+      repo,
+      state: "open",
+      labels: LABEL,
+      per_page: 100,
+    });
+    const pulls = issues.filter((i) => i.pull_request);
+    core.info(`Scheduled sweep: ${pulls.length} open ${LABEL} PR(s).`);
+    for (const p of pulls) {
+      try {
+        await evaluate(p.number);
+      } catch (err) {
+        core.warning(`PR #${p.number}: ${err.message}`);
+      }
+    }
+  } else {
+    await evaluate(context.payload.pull_request.number);
+  }
+}
+
+module.exports = {
+  run,
+  isFormatFile,
+  tallyReviews,
+  decideVerdict,
+  constants: { STATUS_CONTEXT, LABEL, REQUIRED_APPROVALS, PERIOD_DAYS },
+};
diff --git a/ci/format_vote_gate.test.js b/ci/format_vote_gate.test.js
new file mode 100644
index 00000000000..6a13e31eb1f
--- /dev/null
+++ b/ci/format_vote_gate.test.js
@@ -0,0 +1,92 @@
+// Unit tests for the format-spec vote gate logic.
+// Run with: node --test ci/format_vote_gate.test.js
+
+const { test } = require("node:test");
+const assert = require("node:assert/strict");
+
+const { isFormatFile, tallyReviews, decideVerdict } = require("./format_vote_gate.js");
+
+test("isFormatFile matches protos and spec docs only", () => {
+  assert.ok(isFormatFile("protos/table.proto"));
+  assert.ok(isFormatFile("docs/src/format/file.md"));
+  // .proto outside protos/ (e.g. vendored or test fixtures) is not the spec.
+  assert.ok(!isFormatFile("rust/lance-encoding/foo.proto"));
+  assert.ok(!isFormatFile("docs/src/community/voting.md"));
+  assert.ok(!isFormatFile("README.md"));
+  assert.ok(!isFormatFile("protos/AGENTS.md"));
+});
+
+const HEAD = "sha_head";
+const isPmc = (login) => ["alice", "bob", "carol", "dave"].includes(login.toLowerCase());
+const review = (login, state, commitId = HEAD) => ({ user: { login }, state, commit_id: commitId });
+
+test("counts distinct PMC approvals on the head commit", () => {
+  const { approvals, vetoes, staleApprovals } = tallyReviews(
+    [review("alice", "APPROVED"), review("bob", "APPROVED"), review("carol", "APPROVED")],
+    HEAD,
+    "author",
+    isPmc,
+  );
+  assert.deepEqual(approvals.sort(), ["alice", "bob", "carol"]);
+  assert.equal(vetoes.length, 0);
+  assert.equal(staleApprovals.length, 0);
+});
+
+test("only a reviewer's latest review counts", () => {
+  // Alice approved, then later requested changes -> she is a veto, not approval.
+  const { approvals, vetoes } = tallyReviews(
+    [review("alice", "APPROVED"), review("alice", "CHANGES_REQUESTED")],
+    HEAD,
+    "author",
+    isPmc,
+  );
+  assert.deepEqual(approvals, []);
+  assert.deepEqual(vetoes, ["alice"]);
+});
+
+test("approvals on an earlier commit are stale, not counted", () => {
+  const { approvals, staleApprovals } = tallyReviews(
+    [review("alice", "APPROVED", "old_sha"), review("bob", "APPROVED")],
+    HEAD,
+    "author",
+    isPmc,
+  );
+  assert.deepEqual(approvals, ["bob"]);
+  assert.deepEqual(staleApprovals, ["alice"]);
+});
+
+test("ignores the author, non-PMC reviewers, and dismissed reviews", () => {
+  const { approvals, vetoes } = tallyReviews(
+    [
+      review("author", "APPROVED"), // PR author, even if PMC, never counts
+      review("eve", "APPROVED"), // not on the PMC
+      review("dave", "DISMISSED"), // withdrawn
+      review("carol", "COMMENTED"), // a comment is not a vote
+    ],
+    HEAD,
+    "author",
+    isPmc,
+  );
+  assert.deepEqual(approvals, []);
+  assert.deepEqual(vetoes, []);
+});
+
+test("decideVerdict applies blocking conditions in priority order", () => {
+  // Veto wins even with enough approvals and elapsed period.
+  assert.equal(
+    decideVerdict({ vetoCount: 1, approvalCount: 5, periodElapsed: true, required: 3 }),
+    "veto",
+  );
+  assert.equal(
+    decideVerdict({ vetoCount: 0, approvalCount: 2, periodElapsed: true, required: 3 }),
+    "insufficient",
+  );
+  assert.equal(
+    decideVerdict({ vetoCount: 0, approvalCount: 3, periodElapsed: false, required: 3 }),
+    "waiting_period",
+  );
+  assert.equal(
+    decideVerdict({ vetoCount: 0, approvalCount: 3, periodElapsed: true, required: 3 }),
+    "pass",
+  );
+});
diff --git a/ci/sync_pmc_docs.py b/ci/sync_pmc_docs.py
new file mode 100644
index 00000000000..86954acda85
--- /dev/null
+++ b/ci/sync_pmc_docs.py
@@ -0,0 +1,100 @@
+"""Regenerate the PMC roster table in docs from the machine-readable roster.
+
+`docs/src/community/pmc.yaml` is the source of truth for the PMC roster (it also
+drives the format-specification vote gate). This script renders that data into
+the roster table in `docs/src/community/pmc.md`, between the
+`<!-- BEGIN PMC ROSTER -->` and `<!-- END PMC ROSTER -->` markers.
+
+Usage:
+    python ci/sync_pmc_docs.py            # rewrite pmc.md in place
+    python ci/sync_pmc_docs.py --check    # exit 1 if pmc.md is out of sync
+"""
+
+import argparse
+import pathlib
+import sys
+
+import yaml
+
+COMMUNITY_DIR = pathlib.Path(__file__).resolve().parent.parent / "docs/src/community"
+ROSTER_YAML = COMMUNITY_DIR / "pmc.yaml"
+ROSTER_MD = COMMUNITY_DIR / "pmc.md"
+
+BEGIN_MARKER = "<!-- BEGIN PMC ROSTER -->"
+END_MARKER = "<!-- END PMC ROSTER -->"
+
+COLUMNS = [
+    ("Name", "name"),
+    ("GitHub Handle", "handle"),
+    ("Affiliation", "affiliation"),
+    ("Ecosystem Roles", "ecosystem_roles"),
+]
+
+
+def render_table(members):
+    rows = [
+        [str(member.get(key, "") or "") for _, key in COLUMNS] for member in members
+    ]
+    headers = [title for title, _ in COLUMNS]
+    widths = [
+        max(len(headers[i]), *(len(row[i]) for row in rows))
+        if rows
+        else len(headers[i])
+        for i in range(len(COLUMNS))
+    ]
+
+    def format_row(cells):
+        return (
+            "| "
+            + " | ".join(cell.ljust(widths[i]) for i, cell in enumerate(cells))
+            + " |"
+        )
+
+    lines = [format_row(headers), "|" + "|".join("-" * (w + 2) for w in widths) + "|"]
+    lines.extend(format_row(row) for row in rows)
+    return "\n".join(lines)
+
+
+def build_markdown():
+    data = yaml.safe_load(ROSTER_YAML.read_text())
+    members = data["members"]
+    table = render_table(members)
+    block = f"{BEGIN_MARKER}\n{table}\n{END_MARKER}"
+
+    original = ROSTER_MD.read_text()
+    start = original.find(BEGIN_MARKER)
+    end = original.find(END_MARKER)
+    if start == -1 or end == -1:
+        raise SystemExit(
+            f"Could not find roster markers in {ROSTER_MD}. Expected "
+            f"{BEGIN_MARKER!r} and {END_MARKER!r}."
+        )
+    return original[:start] + block + original[end + len(END_MARKER) :]
+
+
+def main():
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument(
+        "--check",
+        action="store_true",
+        help="Exit non-zero if pmc.md is out of sync instead of rewriting it.",
+    )
+    args = parser.parse_args()
+
+    updated = build_markdown()
+    if args.check:
+        if ROSTER_MD.read_text() != updated:
+            print(
+                f"{ROSTER_MD} is out of sync with {ROSTER_YAML}. "
+                "Run `python ci/sync_pmc_docs.py` and commit the result.",
+                file=sys.stderr,
+            )
+            sys.exit(1)
+        print(f"{ROSTER_MD.name} is in sync with {ROSTER_YAML.name}.")
+    else:
+        ROSTER_MD.write_text(updated)
+        print(f"Wrote roster table to {ROSTER_MD}.")
+
+
+if __name__ == "__main__":
+    main()
diff --git a/docs/src/community/pmc.md b/docs/src/community/pmc.md
index 3d9daeaebff..70cb0692def 100644
--- a/docs/src/community/pmc.md
+++ b/docs/src/community/pmc.md
@@ -27,6 +27,9 @@ In addition to the [activities of maintainers](./maintainers.md#activities), PMC
 
 ## Roster
 
+<!-- This table is generated from `pmc.yaml`. Edit that file and run
+     `python ci/sync_pmc_docs.py` to update it; do not edit the table by hand. -->
+<!-- BEGIN PMC ROSTER -->
 | Name            | GitHub Handle   | Affiliation  | Ecosystem Roles                                                                                               |
 |-----------------|-----------------|--------------|---------------------------------------------------------------------------------------------------------------|
 | Yang Cen        | BubbleCal       | LanceDB      | Milvus Contributor                                                                                            |
@@ -41,13 +44,14 @@ In addition to the [activities of maintainers](./maintainers.md#activities), PMC
 | Weston Pace     | westonpace      | LanceDB      | Apache Arrow PMC Member, Substrait SMC Member                                                                 |
 | Calvin Qi       | calvinqi        | Harvey.ai    |                                                                                                               |
 | Prashanth Rao   | prrao87         | LanceDB      |                                                                                                               |
-| Ethan Rosenthal | EthanRosenthal  | Runway AI    |                                                                                                               |                                                 |
+| Ethan Rosenthal | EthanRosenthal  | Runway AI    |                                                                                                               |
 | Tim Saucer      | timsaucer       | Rerun.io     | Apache DataFusion PMC Member                                                                                  |
 | Chang She       | changhiskhan    | LanceDB      | Pandas Co-Author                                                                                              |
 | Jasmine Wang    | onigiriisabunny | LanceDB      | Alluxio PMC Community Manager                                                                                 |
 | Lei Xu          | eddyxu          | LanceDB      | Apache Hadoop PMC Member                                                                                      |
 | Vino Yang       | yanghua         | Bytedance    | Apache Hudi PMC Member, Apache Kyuubi PMC Member, Apache Kylin Committer, Apache Incubation Program Committer |
 | Jack Ye         | jackye1995      | LanceDB      | Apache Iceberg PMC Member, Apache Polaris (incubating) PPMC Member, Apache Incubation Program Committer       |
+<!-- END PMC ROSTER -->
 
 ## Becoming a PMC Member
 
diff --git a/docs/src/community/pmc.yaml b/docs/src/community/pmc.yaml
new file mode 100644
index 00000000000..673e5d7123d
--- /dev/null
+++ b/docs/src/community/pmc.yaml
@@ -0,0 +1,90 @@
+# Source of truth for the Project Management Committee (PMC) roster.
+#
+# This file drives two things, so keep it accurate:
+#   1. The roster table in `pmc.md` (regenerated by `ci/sync_pmc_docs.py`).
+#   2. The format-specification vote gate, which only counts PR approvals from
+#      the `handle`s listed here (see `.github/workflows/format-vote-gate.yml`).
+#
+# Adding or removing a member is itself a PMC vote (roster change). After the
+# vote passes, edit this file and run `python ci/sync_pmc_docs.py` to update the
+# docs table.
+#
+# `handle` must match the member's GitHub login exactly (case-insensitive when
+# matched). `ecosystem_roles` is free-form markdown and may be empty.
+members:
+  - name: Yang Cen
+    handle: BubbleCal
+    affiliation: LanceDB
+    ecosystem_roles: Milvus Contributor
+  - name: Pablo Delgado
+    handle: pablete
+    affiliation: Netflix
+    ecosystem_roles: ""
+  - name: Hao Ding
+    handle: Xuanwo
+    affiliation: LanceDB
+    ecosystem_roles: Apache OpenDAL PMC Chair, Apache Iceberg Committer, Apache Member and [more](https://xuanwo.io/about/)
+  - name: Zhaowei Huang
+    handle: SaintBacchus
+    affiliation: Alibaba
+    ecosystem_roles: Apache Doris Committer
+  - name: Will Jones
+    handle: wjones127
+    affiliation: LanceDB
+    ecosystem_roles: Apache Arrow PMC Member, Apache DataFusion PMC Member, Delta Lake Maintainer
+  - name: Matt Kafonek
+    handle: kafonek
+    affiliation: Runway AI
+    ecosystem_roles: ""
+  - name: Denny Lee
+    handle: dennyglee
+    affiliation: Databricks
+    ecosystem_roles: Unity Catalog Maintainer, Delta Lake Maintainer, Apache Spark Contributor, MLflow Contributor
+  - name: Rob Meng
+    handle: chebbyChefNEQ
+    affiliation: Jump Trading
+    ecosystem_roles: ""
+  - name: Dao Mi
+    handle: dowjones226
+    affiliation: Netflix
+    ecosystem_roles: ""
+  - name: Weston Pace
+    handle: westonpace
+    affiliation: LanceDB
+    ecosystem_roles: Apache Arrow PMC Member, Substrait SMC Member
+  - name: Calvin Qi
+    handle: calvinqi
+    affiliation: Harvey.ai
+    ecosystem_roles: ""
+  - name: Prashanth Rao
+    handle: prrao87
+    affiliation: LanceDB
+    ecosystem_roles: ""
+  - name: Ethan Rosenthal
+    handle: EthanRosenthal
+    affiliation: Runway AI
+    ecosystem_roles: ""
+  - name: Tim Saucer
+    handle: timsaucer
+    affiliation: Rerun.io
+    ecosystem_roles: Apache DataFusion PMC Member
+  - name: Chang She
+    handle: changhiskhan
+    affiliation: LanceDB
+    ecosystem_roles: Pandas Co-Author
+  - name: Jasmine Wang
+    handle: onigiriisabunny
+    affiliation: LanceDB
+    ecosystem_roles: Alluxio PMC Community Manager
+  - name: Lei Xu
+    handle: eddyxu
+    affiliation: LanceDB
+    ecosystem_roles: Apache Hadoop PMC Member
+  - name: Vino Yang
+    handle: yanghua
+    affiliation: Bytedance
+    ecosystem_roles: Apache Hudi PMC Member, Apache Kyuubi PMC Member, Apache Kylin Committer, Apache Incubation Program Committer
+  - name: Jack Ye
+    handle: jackye1995
+    affiliation: LanceDB
+    ecosystem_roles: Apache Iceberg PMC Member, Apache Polaris (incubating) PPMC Member, Apache Incubation Program Committer
diff --git a/docs/src/community/voting.md b/docs/src/community/voting.md
index 8c5ac341e67..338da66790c 100644
--- a/docs/src/community/voting.md
+++ b/docs/src/community/voting.md
@@ -47,7 +47,36 @@ A **-1** binding vote is considered a veto for all decision types. Vetoes:
 | Release a new stable major version of the core project                            | 3                                            | PMC                            | GitHub Discussions                    | 3 days         |
 | Release a new stable minor version of the core project                            | 3                                            | PMC                            | GitHub Discussions                    | 3 days         |
 | Release a new stable patch version of the core project                            | 3                                            | PMC                            | GitHub Discussions                    | N/A            |
-| Lance Format Specification modifications                                      | 3 (excluding proposer)                       | PMC                            | GitHub Discussions (with a GitHub PR) | 1 week         |
+| Lance Format Specification modifications                                      | 3 (excluding proposer)                       | PMC                            | GitHub PR (see [below](#lance-format-specification-vote-gate)) | 1 week         |
 | Code modifications in the core project (except changes to format specifications)  | 1 (excluding proposer)                       | Maintainers with write access  | GitHub PR                             | N/A            |
 | Release a new stable version of subprojects                                   | 1                                            | PMC                            | GitHub Discussions                    | N/A            |
 | Code modifications in subprojects                                             | 1 (excluding proposer)                       | Contributors with write access | GitHub PR                             | N/A            |
+
+## Lance Format Specification Vote Gate
+
+Votes on Lance format-specification changes are cast and counted directly on the
+pull request, and the requirement is enforced structurally in CI rather than by
+convention.
+
+A PR is considered a format-specification change when it modifies the protobuf
+definitions (`protos/**/*.proto`) or the spec documentation (`docs/src/format/**`).
+The [format spec vote gate](https://github.com/lance-format/lance/blob/main/.github/workflows/format-vote-gate.yml)
+labels such PRs `format-change` and blocks merging until all of the following hold:
+
+- **Three binding +1 votes.** Three PMC members have approved the PR, excluding
+  the proposer. Cast +1 by approving the PR. Only approvals on the latest commit
+  count — pushing new commits invalidates earlier approvals, since the proposal
+  has changed.
+- **No veto.** No PMC member has an outstanding "Request changes" review. A `-1`
+  binding vote (cast by requesting changes) is a veto and blocks the merge until
+  withdrawn.
+- **Minimum voting period.** At least one week has elapsed since the PR was
+  flagged as a format change.
+
+The gate is the `format-spec-vote` required status check on protected branches.
+The PMC roster used to count votes is read from
+[`docs/src/community/pmc.yaml`](./pmc.md).
+
+For a trivial edit that does not change the format — a typo, wording, or
+formatting fix — a PMC member may remove the `format-change` label to waive the
+vote.

From 82c87750724cef075bac94cd6bfca73659a718a1 Mon Sep 17 00:00:00 2001
From: Will Jones <willjones127@gmail.com>
Date: Mon, 22 Jun 2026 11:25:11 -0700
Subject: [PATCH 2/2] =?UTF-8?q?ci:=20address=20review=20=E2=80=94=20Python?=
 =?UTF-8?q?=20gate,=20path-labeler,=20build-time=20roster?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Responds to PR review feedback:

- Rewrite the gate in Python (PyGithub) instead of JS, for readability — most
  maintainers are more familiar with Python.
- Apply the `format-change` label via the existing path labeler
  (.github/labeler-area.yml) instead of the gate. The gate now reads the label
  and leaves PRs without it alone, posting only a passing status (so the
  required check never blocks non-format PRs). Trivial edits are waived with a
  `format-waived` label applied by a PMC member.
- Render the PMC roster table at docs build time via an MkDocs hook
  (docs/hooks/pmc_roster.py) instead of a committed table kept in sync by a
  script; pmc.yaml stays the source of truth. Drops ci/sync_pmc_docs.py.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
---
 .github/labeler-area.yml               |  10 +
 .github/workflows/ci-scripts.yml       |  14 +-
 .github/workflows/docs-check.yml       |   5 -
 .github/workflows/format-vote-gate.yml |  37 ++-
 ci/format_vote_gate.js                 | 311 -------------------------
 ci/format_vote_gate.py                 | 289 +++++++++++++++++++++++
 ci/format_vote_gate.test.js            |  92 --------
 ci/sync_pmc_docs.py                    | 100 --------
 ci/test_format_vote_gate.py            |  87 +++++++
 docs/hooks/pmc_roster.py               |  46 ++++
 docs/mkdocs.yml                        |   3 +
 docs/src/community/pmc.md              |  28 +--
 docs/src/community/pmc.yaml            |   6 +-
 docs/src/community/voting.md           |   9 +-
 14 files changed, 471 insertions(+), 566 deletions(-)
 delete mode 100644 ci/format_vote_gate.js
 create mode 100644 ci/format_vote_gate.py
 delete mode 100644 ci/format_vote_gate.test.js
 delete mode 100644 ci/sync_pmc_docs.py
 create mode 100644 ci/test_format_vote_gate.py
 create mode 100644 docs/hooks/pmc_roster.py

diff --git a/.github/labeler-area.yml b/.github/labeler-area.yml
index 9afb49172af..0eab34eafb6 100644
--- a/.github/labeler-area.yml
+++ b/.github/labeler-area.yml
@@ -37,6 +37,16 @@ A-format:
           - "protos/**"
           - "docs/src/format/**"
 
+# Drives the format-spec vote gate (.github/workflows/format-vote-gate.yml):
+# any change to the proto definitions or the spec docs requires a PMC vote.
+# Scoped to *.proto (not e.g. protos/AGENTS.md) since only the IDL and spec are
+# the format. A PMC member waives a trivial edit with the `format-waived` label.
+format-change:
+  - changed-files:
+      - any-glob-to-any-file:
+          - "protos/**/*.proto"
+          - "docs/src/format/**"
+
 # Lockfiles are intentionally not excluded: a pure dependency bump gets both
 # A-python and A-deps. Over-labeling beats dropping the area signal on PRs that
 # touch python code alongside a lockfile.
diff --git a/.github/workflows/ci-scripts.yml b/.github/workflows/ci-scripts.yml
index ab7bb62cc40..5cd3d483786 100644
--- a/.github/workflows/ci-scripts.yml
+++ b/.github/workflows/ci-scripts.yml
@@ -13,8 +13,8 @@ on:
       - main
       - release/**
     paths:
-      - ci/format_vote_gate.js
-      - ci/format_vote_gate.test.js
+      - ci/format_vote_gate.py
+      - ci/test_format_vote_gate.py
       - .github/workflows/format-vote-gate.yml
       - .github/workflows/ci-scripts.yml
 
@@ -28,9 +28,11 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4
-      - name: Set up Node
-        uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4
+      - name: Set up Python
+        uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065 # v5
         with:
-          node-version: "20"
+          python-version: "3.12"
+      - name: Install pytest
+        run: pip install pytest
       - name: Run tests
-        run: node --test ci/format_vote_gate.test.js
+        run: pytest ci/test_format_vote_gate.py
diff --git a/.github/workflows/docs-check.yml b/.github/workflows/docs-check.yml
index 15576e42f22..2eda3de66b4 100644
--- a/.github/workflows/docs-check.yml
+++ b/.github/workflows/docs-check.yml
@@ -11,7 +11,6 @@ on:
       - release/**
     paths:
       - docs/**
-      - ci/sync_pmc_docs.py
       - .github/workflows/docs-check.yml
 
 permissions:
@@ -42,7 +41,3 @@ jobs:
         working-directory: docs
         run: |
           uv run mkdocs-linkcheck src
-      - name: Check PMC roster table is in sync with pmc.yaml
-        working-directory: docs
-        run: |
-          uv run python ../ci/sync_pmc_docs.py --check
diff --git a/.github/workflows/format-vote-gate.yml b/.github/workflows/format-vote-gate.yml
index ec32568d3bd..e98840830ea 100644
--- a/.github/workflows/format-vote-gate.yml
+++ b/.github/workflows/format-vote-gate.yml
@@ -1,9 +1,10 @@
 name: Format spec vote gate
 
 # Structurally enforces the PMC vote required for Lance format-specification
-# changes (see https://lance.org/community/voting/). A PR that touches the
-# format spec (`protos/**/*.proto`, `docs/src/format/**`) is labelled
-# `format-change` and cannot merge until it has 3 binding +1 votes from PMC
+# changes (see https://lance.org/community/voting/). The path labeler
+# (.github/labeler-area.yml) applies the `format-change` label to PRs that touch
+# the format spec (`protos/**/*.proto`, `docs/src/format/**`); this gate reads
+# that label and blocks merging until the PR has 3 binding +1 votes from PMC
 # members (PR approvals, excluding the author), has no outstanding veto (a PMC
 # "Request changes" review), and the 1-week voting period has elapsed.
 #
@@ -13,12 +14,12 @@ name: Format spec vote gate
 # release branches). The status is posted on *every* PR — success immediately
 # for non-format PRs — so a required check is never left pending forever.
 #
-# A PMC member may exempt a trivial edit (typo, wording, formatting) by removing
-# the `format-change` label; the gate respects that and will not re-add it.
+# A PMC member may waive a trivial edit (typo, wording, formatting) by applying
+# the `format-waived` label.
 #
-# Uses pull_request_target so the token can label PRs and post statuses on
-# fork-based PRs. It never checks out or executes PR code: it reads the trusted
-# base checkout (for the PMC roster) and queries the API only.
+# Uses pull_request_target so the token can post statuses/comments on fork-based
+# PRs. It never checks out or executes PR code: it reads the trusted base
+# checkout (for the PMC roster and this script) and queries the API only.
 
 on:
   pull_request_target:
@@ -48,17 +49,13 @@ jobs:
     steps:
       - name: Checkout base
         uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4
-      - name: Set up Node
-        uses: actions/setup-node@49933ea5288caeca8642d1e84afbd3f7d6820020 # v4
+      - name: Set up Python
+        uses: actions/setup-python@a26af69be951a213d495a4c3e4e4022e16d87065 # v5
         with:
-          node-version: "20"
-      - name: Install js-yaml
-        run: npm install --no-save js-yaml@4
+          python-version: "3.12"
+      - name: Install dependencies
+        run: pip install PyGithub PyYAML
       - name: Evaluate vote
-        uses: actions/github-script@f28e40c7f34bde8b3046d885e986cb6290c5673b # v7
-        with:
-          script: |
-            const path = require('path');
-            // Loaded from the trusted base checkout, never from PR code.
-            const gate = require(path.join(process.env.GITHUB_WORKSPACE, 'ci', 'format_vote_gate.js'));
-            await gate.run({ github, context, core });
+        run: python ci/format_vote_gate.py
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
diff --git a/ci/format_vote_gate.js b/ci/format_vote_gate.js
deleted file mode 100644
index bb5208fe8ca..00000000000
--- a/ci/format_vote_gate.js
+++ /dev/null
@@ -1,311 +0,0 @@
-// Logic for the format-specification vote gate
-// (`.github/workflows/format-vote-gate.yml`). Extracted into a module so the
-// vote-counting rules can be unit tested (see `format_vote_gate.test.js`); the
-// workflow loads it from the trusted base checkout and calls `run`.
-
-const fs = require("fs");
-const path = require("path");
-
-const STATUS_CONTEXT = "format-spec-vote";
-const LABEL = "format-change";
-const COMMENT_MARKER = "<!-- format-spec-vote-status -->";
-const REQUIRED_APPROVALS = 3;
-const PERIOD_DAYS = 7;
-const PERIOD_MS = PERIOD_DAYS * 24 * 60 * 60 * 1000;
-const VOTING_URL = "https://lance.org/community/voting/";
-const DAY_MS = 24 * 60 * 60 * 1000;
-
-// The Lance format specification is the proto definitions and the spec docs.
-// Changes to either require a PMC vote.
-function isFormatFile(p) {
-  return (
-    (p.endsWith(".proto") && p.startsWith("protos/")) ||
-    p.startsWith("docs/src/format/")
-  );
-}
-
-// Each PMC member's current stance is their most recent non-comment review.
-// Approvals are only counted on the head commit (stale approvals from earlier
-// commits do not count toward the bar); a "changes requested" review is a veto
-// and blocks regardless of commit until withdrawn. The PR author never counts,
-// even if they are on the PMC.
-function tallyReviews(reviews, headSha, author, isPmc) {
-  const latest = new Map();
-  for (const r of reviews) {
-    const login = r.user && r.user.login;
-    if (!login || !isPmc(login) || login === author) continue;
-    if (!["APPROVED", "CHANGES_REQUESTED", "DISMISSED"].includes(r.state)) {
-      continue;
-    }
-    latest.set(login.toLowerCase(), {
-      login,
-      state: r.state,
-      commitId: r.commit_id,
-    });
-  }
-  const approvals = [];
-  const staleApprovals = [];
-  const vetoes = [];
-  for (const v of latest.values()) {
-    if (v.state === "APPROVED") {
-      (v.commitId === headSha ? approvals : staleApprovals).push(v.login);
-    } else if (v.state === "CHANGES_REQUESTED") {
-      vetoes.push(v.login);
-    }
-  }
-  return { approvals, staleApprovals, vetoes };
-}
-
-// Pure decision: which blocking condition (if any) applies, in priority order.
-function decideVerdict({ vetoCount, approvalCount, periodElapsed, required }) {
-  if (vetoCount > 0) return "veto";
-  if (approvalCount < required) return "insufficient";
-  if (!periodElapsed) return "waiting_period";
-  return "pass";
-}
-
-const fmtList = (xs) => (xs.length ? xs.map((u) => `@${u}`).join(", ") : "none");
-
-function loadPmc(workspace) {
-  const yaml = require(path.join(workspace, "node_modules", "js-yaml"));
-  const rosterPath = path.join(workspace, "docs", "src", "community", "pmc.yaml");
-  const roster = yaml.load(fs.readFileSync(rosterPath, "utf8"));
-  return new Set(roster.members.map((m) => m.handle.toLowerCase()));
-}
-
-async function run({ github, context, core }) {
-  const { owner, repo } = context.repo;
-  const workspace = process.env.GITHUB_WORKSPACE;
-  const pmc = loadPmc(workspace);
-  const isPmc = (login) => login != null && pmc.has(login.toLowerCase());
-  const runUrl = `${context.serverUrl}/${owner}/${repo}/actions/runs/${context.runId}`;
-
-  async function setStatus(sha, state, description) {
-    await github.rest.repos.createCommitStatus({
-      owner,
-      repo,
-      sha,
-      state,
-      context: STATUS_CONTEXT,
-      description: description.slice(0, 140),
-      target_url: runUrl,
-    });
-  }
-
-  async function upsertComment(prNumber, body) {
-    const full = `${COMMENT_MARKER}\n${body}`;
-    const comments = await github.paginate(github.rest.issues.listComments, {
-      owner,
-      repo,
-      issue_number: prNumber,
-      per_page: 100,
-    });
-    const existing = comments.find((c) => c.body && c.body.includes(COMMENT_MARKER));
-    if (existing) {
-      if (existing.body !== full) {
-        await github.rest.issues.updateComment({
-          owner,
-          repo,
-          comment_id: existing.id,
-          body: full,
-        });
-      }
-    } else {
-      await github.rest.issues.createComment({
-        owner,
-        repo,
-        issue_number: prNumber,
-        body: full,
-      });
-    }
-  }
-
-  // Returns { firstAddedAt, removedByPmc } for LABEL on this PR, from the
-  // timeline: when the label was first applied (the vote-period anchor) and
-  // whether a PMC member deliberately removed it (a trivial-edit waiver).
-  async function labelHistory(prNumber) {
-    const events = await github.paginate(
-      github.rest.issues.listEventsForTimeline,
-      { owner, repo, issue_number: prNumber, per_page: 100 },
-    );
-    let firstAddedAt = null;
-    let removedByPmc = false;
-    for (const e of events) {
-      if (!e.label || e.label.name !== LABEL) continue;
-      if (e.event === "labeled" && !firstAddedAt) {
-        firstAddedAt = e.created_at;
-      } else if (e.event === "unlabeled" && isPmc(e.actor && e.actor.login)) {
-        removedByPmc = true;
-      }
-    }
-    return { firstAddedAt, removedByPmc };
-  }
-
-  async function evaluate(prNumber) {
-    const { data: pr } = await github.rest.pulls.get({
-      owner,
-      repo,
-      pull_number: prNumber,
-    });
-    if (pr.state !== "open") {
-      core.info(`PR #${prNumber} is ${pr.state}; skipping.`);
-      return;
-    }
-    const headSha = pr.head.sha;
-    const author = pr.user.login;
-
-    const files = await github.paginate(github.rest.pulls.listFiles, {
-      owner,
-      repo,
-      pull_number: prNumber,
-      per_page: 100,
-    });
-    const touchesFormat = files.map((f) => f.filename).some(isFormatFile);
-
-    let hasLabel = pr.labels.some((l) => l.name === LABEL);
-    const { firstAddedAt, removedByPmc } = await labelHistory(prNumber);
-
-    // Auto-apply the label, unless a PMC member deliberately removed it.
-    if (touchesFormat && !hasLabel && !removedByPmc) {
-      await github.rest.issues.addLabels({
-        owner,
-        repo,
-        issue_number: prNumber,
-        labels: [LABEL],
-      });
-      hasLabel = true;
-    }
-
-    if (!hasLabel) {
-      await setStatus(
-        headSha,
-        "success",
-        removedByPmc
-          ? "Format-spec vote waived by a PMC member."
-          : "No format-spec change; vote not required.",
-      );
-      if (removedByPmc) {
-        await upsertComment(
-          prNumber,
-          `> [!NOTE]\n> A PMC member removed the \`${LABEL}\` label, ` +
-            `waiving the format-spec vote for this PR (trivial edit).`,
-        );
-      }
-      core.info(`PR #${prNumber}: no vote required.`);
-      return;
-    }
-
-    const reviews = await github.paginate(github.rest.pulls.listReviews, {
-      owner,
-      repo,
-      pull_number: prNumber,
-      per_page: 100,
-    });
-    const { approvals, staleApprovals, vetoes } = tallyReviews(
-      reviews,
-      headSha,
-      author,
-      isPmc,
-    );
-
-    const now = new Date();
-    const voteStart = firstAddedAt ? new Date(firstAddedAt) : now;
-    const periodEnds = new Date(voteStart.getTime() + PERIOD_MS);
-    const periodElapsed = now >= periodEnds;
-    const verdict = decideVerdict({
-      vetoCount: vetoes.length,
-      approvalCount: approvals.length,
-      periodElapsed,
-      required: REQUIRED_APPROVALS,
-    });
-
-    const endDate = periodEnds.toISOString().slice(0, 10);
-    let state, summary, headline;
-    if (verdict === "veto") {
-      state = "failure";
-      summary = `Vetoed by ${vetoes.length} PMC member(s).`;
-      headline = `❌ Blocked — vetoed by ${fmtList(vetoes)}`;
-    } else if (verdict === "insufficient") {
-      state = "failure";
-      summary = `${approvals.length}/${REQUIRED_APPROVALS} PMC approvals on this commit.`;
-      headline = `❌ Blocked — ${approvals.length} of ${REQUIRED_APPROVALS} required approvals`;
-    } else if (verdict === "waiting_period") {
-      state = "failure";
-      summary = `Approved; voting period ends ${endDate}.`;
-      headline =
-        `⏳ Approvals met (${approvals.length}/${REQUIRED_APPROVALS}); ` +
-        `voting period ends ${endDate}`;
-    } else {
-      state = "success";
-      summary = `Passed — ${approvals.length} PMC approvals, period elapsed.`;
-      headline = `✅ Vote passed — ${approvals.length} PMC approvals, voting period elapsed`;
-    }
-
-    const daysLeft = Math.max(0, Math.ceil((periodEnds.getTime() - now.getTime()) / DAY_MS));
-    const periodCell = periodElapsed
-      ? `elapsed (ended ${endDate})`
-      : `ends ${endDate} (${daysLeft} day(s) left)`;
-    const approvalCell =
-      `${fmtList(approvals)} (${approvals.length}/${REQUIRED_APPROVALS})` +
-      (staleApprovals.length
-        ? ` — stale, re-approve needed: ${fmtList(staleApprovals)}`
-        : "");
-
-    const body = [
-      "> [!IMPORTANT]",
-      "> ## Format specification vote",
-      "",
-      "This PR modifies the Lance format specification, so it requires " +
-        `**${REQUIRED_APPROVALS} binding +1 votes from PMC members** ` +
-        "(excluding the proposer) and a minimum " +
-        `**${PERIOD_DAYS}-day** voting period before it can merge. ` +
-        "Vote by approving this PR (+1) or requesting changes (−1, a veto). " +
-        `See the [voting process](${VOTING_URL}).`,
-      "",
-      `**Status: ${headline}**`,
-      "",
-      "| | |",
-      "|---|---|",
-      `| Approvals (this commit) | ${approvalCell} |`,
-      `| Vetoes | ${fmtList(vetoes)} |`,
-      `| Voting period | ${periodCell} |`,
-      "",
-      "<sub>Updated automatically by the format-spec vote gate. A PMC member " +
-        `may remove the \`${LABEL}\` label to waive the vote for a trivial edit ` +
-        "(typo, wording, formatting).</sub>",
-    ].join("\n");
-
-    await setStatus(headSha, state, summary);
-    await upsertComment(prNumber, body);
-    core.info(`PR #${prNumber}: ${summary}`);
-  }
-
-  if (context.eventName === "schedule") {
-    const issues = await github.paginate(github.rest.issues.listForRepo, {
-      owner,
-      repo,
-      state: "open",
-      labels: LABEL,
-      per_page: 100,
-    });
-    const pulls = issues.filter((i) => i.pull_request);
-    core.info(`Scheduled sweep: ${pulls.length} open ${LABEL} PR(s).`);
-    for (const p of pulls) {
-      try {
-        await evaluate(p.number);
-      } catch (err) {
-        core.warning(`PR #${p.number}: ${err.message}`);
-      }
-    }
-  } else {
-    await evaluate(context.payload.pull_request.number);
-  }
-}
-
-module.exports = {
-  run,
-  isFormatFile,
-  tallyReviews,
-  decideVerdict,
-  constants: { STATUS_CONTEXT, LABEL, REQUIRED_APPROVALS, PERIOD_DAYS },
-};
diff --git a/ci/format_vote_gate.py b/ci/format_vote_gate.py
new file mode 100644
index 00000000000..90f41b8490c
--- /dev/null
+++ b/ci/format_vote_gate.py
@@ -0,0 +1,289 @@
+"""Format-specification vote gate (see `.github/workflows/format-vote-gate.yml`).
+
+Structurally enforces the PMC vote required for Lance format-specification
+changes (https://lance.org/community/voting/). The `format-change` label is
+applied by the path labeler (`.github/labeler-area.yml`); this script reads it
+and publishes the `format-spec-vote` commit status, which blocks merging until:
+
+  * 3 PMC members have approved the PR (excluding the author), counted only on
+    the head commit so new pushes invalidate stale approvals;
+  * no PMC member has an outstanding "Request changes" review (a veto); and
+  * the 1-week voting period (from when `format-change` was first applied) has
+    elapsed.
+
+A PMC member can waive a trivial edit by applying the `format-waived` label.
+Non-format PRs get a passing status immediately and are otherwise left alone.
+
+The vote-counting rules are pure functions (`tally_reviews`, `decide_verdict`)
+unit tested in `test_format_vote_gate.py`; `main` wires them to the GitHub API.
+"""
+
+import json
+import os
+from datetime import datetime, timedelta, timezone
+
+STATUS_CONTEXT = "format-spec-vote"
+FORMAT_LABEL = "format-change"
+WAIVED_LABEL = "format-waived"
+COMMENT_MARKER = "<!-- format-spec-vote-status -->"
+REQUIRED_APPROVALS = 3
+PERIOD_DAYS = 7
+VOTING_URL = "https://lance.org/community/voting/"
+
+# Review states that express a stance; COMMENTED/PENDING are ignored.
+_STANCE_STATES = ("APPROVED", "CHANGES_REQUESTED", "DISMISSED")
+
+
+def tally_reviews(reviews, head_sha, author, is_pmc):
+    """Tally PMC votes from a PR's reviews.
+
+    `reviews` is an ordered list of dicts with `login`, `state`, `commit_id`.
+    A member's stance is their most recent stance review. Approvals only count
+    on the head commit; earlier ones are stale. A "changes requested" review is
+    a veto regardless of commit. The PR author never counts.
+    """
+    latest = {}
+    for review in reviews:
+        login = review["login"]
+        if not login or not is_pmc(login) or login == author:
+            continue
+        if review["state"] not in _STANCE_STATES:
+            continue
+        latest[login.lower()] = review
+
+    approvals, stale_approvals, vetoes = [], [], []
+    for review in latest.values():
+        if review["state"] == "APPROVED":
+            target = approvals if review["commit_id"] == head_sha else stale_approvals
+            target.append(review["login"])
+        elif review["state"] == "CHANGES_REQUESTED":
+            vetoes.append(review["login"])
+    return approvals, stale_approvals, vetoes
+
+
+def decide_verdict(veto_count, approval_count, period_elapsed, required):
+    """Return the blocking condition (if any), in priority order."""
+    if veto_count > 0:
+        return "veto"
+    if approval_count < required:
+        return "insufficient"
+    if not period_elapsed:
+        return "waiting_period"
+    return "pass"
+
+
+def _fmt_list(logins):
+    return ", ".join(f"@{login}" for login in logins) if logins else "none"
+
+
+def _as_utc(dt):
+    return dt.replace(tzinfo=timezone.utc) if dt.tzinfo is None else dt
+
+
+def _build_comment(headline, approval_cell, vetoes, period_cell):
+    return "\n".join(
+        [
+            COMMENT_MARKER,
+            "> [!IMPORTANT]",
+            "> ## Format specification vote",
+            "",
+            "This PR modifies the Lance format specification, so it requires "
+            f"**{REQUIRED_APPROVALS} binding +1 votes from PMC members** "
+            "(excluding the proposer) and a minimum "
+            f"**{PERIOD_DAYS}-day** voting period before it can merge. "
+            "Vote by approving this PR (+1) or requesting changes (−1, a veto). "
+            f"See the [voting process]({VOTING_URL}).",
+            "",
+            f"**Status: {headline}**",
+            "",
+            "| | |",
+            "|---|---|",
+            f"| Approvals (this commit) | {approval_cell} |",
+            f"| Vetoes | {_fmt_list(vetoes)} |",
+            f"| Voting period | {period_cell} |",
+            "",
+            "<sub>Updated automatically by the format-spec vote gate. A PMC member "
+            f"may apply the `{WAIVED_LABEL}` label to waive the vote for a trivial "
+            "edit (typo, wording, formatting).</sub>",
+        ]
+    )
+
+
+def _load_pmc(workspace):
+    import yaml
+
+    roster_path = os.path.join(workspace, "docs", "src", "community", "pmc.yaml")
+    with open(roster_path) as handle:
+        roster = yaml.safe_load(handle)
+    return {member["handle"].lower() for member in roster["members"]}
+
+
+class Gate:
+    def __init__(self, repo, pmc, run_url):
+        self.repo = repo
+        self.pmc = pmc
+        self.run_url = run_url
+
+    def is_pmc(self, login):
+        return login is not None and login.lower() in self.pmc
+
+    def set_status(self, sha, state, description):
+        self.repo.get_commit(sha).create_status(
+            state=state,
+            context=STATUS_CONTEXT,
+            description=description[:140],
+            target_url=self.run_url,
+        )
+
+    def upsert_comment(self, issue, body):
+        for comment in issue.get_comments():
+            if COMMENT_MARKER in (comment.body or ""):
+                if comment.body != body:
+                    comment.edit(body)
+                return
+        issue.create_comment(body)
+
+    def label_facts(self, issue):
+        """When `format-change` was first applied, and whether a PMC waived."""
+        first_added = None
+        waived_by_pmc = False
+        for event in issue.get_events():
+            if event.event not in ("labeled", "unlabeled") or event.label is None:
+                continue
+            name = event.label.name
+            actor = event.actor.login if event.actor else None
+            if (
+                name == FORMAT_LABEL
+                and event.event == "labeled"
+                and first_added is None
+            ):
+                first_added = _as_utc(event.created_at)
+            elif (
+                name == WAIVED_LABEL and event.event == "labeled" and self.is_pmc(actor)
+            ):
+                waived_by_pmc = True
+        return first_added, waived_by_pmc
+
+    def evaluate(self, number):
+        pr = self.repo.get_pull(number)
+        if pr.state != "open":
+            print(f"PR #{number} is {pr.state}; skipping.")
+            return
+        head_sha = pr.head.sha
+        labels = {label.name for label in pr.labels}
+
+        # Non-format PRs get a passing status and are otherwise left alone.
+        if FORMAT_LABEL not in labels:
+            self.set_status(
+                head_sha, "success", "No format-spec change; vote not required."
+            )
+            print(f"PR #{number}: not a format change.")
+            return
+
+        issue = self.repo.get_issue(number)
+        first_added, waived = self.label_facts(issue)
+
+        if WAIVED_LABEL in labels and waived:
+            self.set_status(
+                head_sha, "success", "Format-spec vote waived by a PMC member."
+            )
+            print(f"PR #{number}: vote waived.")
+            return
+
+        reviews = [
+            {
+                "login": review.user.login if review.user else None,
+                "state": review.state,
+                "commit_id": review.commit_id,
+            }
+            for review in pr.get_reviews()
+        ]
+        approvals, stale, vetoes = tally_reviews(
+            reviews, head_sha, pr.user.login, self.is_pmc
+        )
+
+        now = datetime.now(timezone.utc)
+        vote_start = first_added or now
+        period_ends = vote_start + timedelta(days=PERIOD_DAYS)
+        period_elapsed = now >= period_ends
+        verdict = decide_verdict(
+            len(vetoes), len(approvals), period_elapsed, REQUIRED_APPROVALS
+        )
+
+        end_date = period_ends.date().isoformat()
+        if verdict == "veto":
+            state, summary = "failure", f"Vetoed by {len(vetoes)} PMC member(s)."
+            headline = f"❌ Blocked — vetoed by {_fmt_list(vetoes)}"
+        elif verdict == "insufficient":
+            state = "failure"
+            summary = (
+                f"{len(approvals)}/{REQUIRED_APPROVALS} PMC approvals on this commit."
+            )
+            headline = f"❌ Blocked — {len(approvals)} of {REQUIRED_APPROVALS} required approvals"
+        elif verdict == "waiting_period":
+            state, summary = "failure", f"Approved; voting period ends {end_date}."
+            headline = (
+                f"⏳ Approvals met ({len(approvals)}/{REQUIRED_APPROVALS}); "
+                f"voting period ends {end_date}"
+            )
+        else:
+            state = "success"
+            summary = f"Passed — {len(approvals)} PMC approvals, period elapsed."
+            headline = f"✅ Vote passed — {len(approvals)} PMC approvals, voting period elapsed"
+
+        days_left = max(0, -(-(period_ends - now).days))  # ceil of day difference
+        period_cell = (
+            f"elapsed (ended {end_date})"
+            if period_elapsed
+            else f"ends {end_date} ({days_left} day(s) left)"
+        )
+        approval_cell = (
+            f"{_fmt_list(approvals)} ({len(approvals)}/{REQUIRED_APPROVALS})"
+        )
+        if stale:
+            approval_cell += f" — stale, re-approve needed: {_fmt_list(stale)}"
+
+        self.set_status(head_sha, state, summary)
+        self.upsert_comment(
+            issue, _build_comment(headline, approval_cell, vetoes, period_cell)
+        )
+        print(f"PR #{number}: {summary}")
+
+
+def main():
+    from github import Github
+
+    workspace = os.environ["GITHUB_WORKSPACE"]
+    token = os.environ["GITHUB_TOKEN"]
+    repo_name = os.environ["GITHUB_REPOSITORY"]
+    event_name = os.environ["GITHUB_EVENT_NAME"]
+    run_url = (
+        f"{os.environ['GITHUB_SERVER_URL']}/{repo_name}/actions/runs/"
+        f"{os.environ['GITHUB_RUN_ID']}"
+    )
+
+    repo = Github(token).get_repo(repo_name)
+    gate = Gate(repo, _load_pmc(workspace), run_url)
+
+    if event_name == "schedule":
+        # The schedule trigger has no PR context, so sweep every open
+        # format-change PR to re-check the voting-period clock.
+        pulls = [
+            pr
+            for pr in repo.get_pulls(state="open")
+            if any(label.name == FORMAT_LABEL for label in pr.labels)
+        ]
+        print(f"Scheduled sweep: {len(pulls)} open {FORMAT_LABEL} PR(s).")
+        for pr in pulls:
+            try:
+                gate.evaluate(pr.number)
+            except Exception as err:  # noqa: BLE001 - keep sweeping other PRs
+                print(f"PR #{pr.number}: {err}")
+    else:
+        with open(os.environ["GITHUB_EVENT_PATH"]) as handle:
+            event = json.load(handle)
+        gate.evaluate(event["pull_request"]["number"])
+
+
+if __name__ == "__main__":
+    main()
diff --git a/ci/format_vote_gate.test.js b/ci/format_vote_gate.test.js
deleted file mode 100644
index 6a13e31eb1f..00000000000
--- a/ci/format_vote_gate.test.js
+++ /dev/null
@@ -1,92 +0,0 @@
-// Unit tests for the format-spec vote gate logic.
-// Run with: node --test ci/format_vote_gate.test.js
-
-const { test } = require("node:test");
-const assert = require("node:assert/strict");
-
-const { isFormatFile, tallyReviews, decideVerdict } = require("./format_vote_gate.js");
-
-test("isFormatFile matches protos and spec docs only", () => {
-  assert.ok(isFormatFile("protos/table.proto"));
-  assert.ok(isFormatFile("docs/src/format/file.md"));
-  // .proto outside protos/ (e.g. vendored or test fixtures) is not the spec.
-  assert.ok(!isFormatFile("rust/lance-encoding/foo.proto"));
-  assert.ok(!isFormatFile("docs/src/community/voting.md"));
-  assert.ok(!isFormatFile("README.md"));
-  assert.ok(!isFormatFile("protos/AGENTS.md"));
-});
-
-const HEAD = "sha_head";
-const isPmc = (login) => ["alice", "bob", "carol", "dave"].includes(login.toLowerCase());
-const review = (login, state, commitId = HEAD) => ({ user: { login }, state, commit_id: commitId });
-
-test("counts distinct PMC approvals on the head commit", () => {
-  const { approvals, vetoes, staleApprovals } = tallyReviews(
-    [review("alice", "APPROVED"), review("bob", "APPROVED"), review("carol", "APPROVED")],
-    HEAD,
-    "author",
-    isPmc,
-  );
-  assert.deepEqual(approvals.sort(), ["alice", "bob", "carol"]);
-  assert.equal(vetoes.length, 0);
-  assert.equal(staleApprovals.length, 0);
-});
-
-test("only a reviewer's latest review counts", () => {
-  // Alice approved, then later requested changes -> she is a veto, not approval.
-  const { approvals, vetoes } = tallyReviews(
-    [review("alice", "APPROVED"), review("alice", "CHANGES_REQUESTED")],
-    HEAD,
-    "author",
-    isPmc,
-  );
-  assert.deepEqual(approvals, []);
-  assert.deepEqual(vetoes, ["alice"]);
-});
-
-test("approvals on an earlier commit are stale, not counted", () => {
-  const { approvals, staleApprovals } = tallyReviews(
-    [review("alice", "APPROVED", "old_sha"), review("bob", "APPROVED")],
-    HEAD,
-    "author",
-    isPmc,
-  );
-  assert.deepEqual(approvals, ["bob"]);
-  assert.deepEqual(staleApprovals, ["alice"]);
-});
-
-test("ignores the author, non-PMC reviewers, and dismissed reviews", () => {
-  const { approvals, vetoes } = tallyReviews(
-    [
-      review("author", "APPROVED"), // PR author, even if PMC, never counts
-      review("eve", "APPROVED"), // not on the PMC
-      review("dave", "DISMISSED"), // withdrawn
-      review("carol", "COMMENTED"), // a comment is not a vote
-    ],
-    HEAD,
-    "author",
-    isPmc,
-  );
-  assert.deepEqual(approvals, []);
-  assert.deepEqual(vetoes, []);
-});
-
-test("decideVerdict applies blocking conditions in priority order", () => {
-  // Veto wins even with enough approvals and elapsed period.
-  assert.equal(
-    decideVerdict({ vetoCount: 1, approvalCount: 5, periodElapsed: true, required: 3 }),
-    "veto",
-  );
-  assert.equal(
-    decideVerdict({ vetoCount: 0, approvalCount: 2, periodElapsed: true, required: 3 }),
-    "insufficient",
-  );
-  assert.equal(
-    decideVerdict({ vetoCount: 0, approvalCount: 3, periodElapsed: false, required: 3 }),
-    "waiting_period",
-  );
-  assert.equal(
-    decideVerdict({ vetoCount: 0, approvalCount: 3, periodElapsed: true, required: 3 }),
-    "pass",
-  );
-});
diff --git a/ci/sync_pmc_docs.py b/ci/sync_pmc_docs.py
deleted file mode 100644
index 86954acda85..00000000000
--- a/ci/sync_pmc_docs.py
+++ /dev/null
@@ -1,100 +0,0 @@
-"""Regenerate the PMC roster table in docs from the machine-readable roster.
-
-`docs/src/community/pmc.yaml` is the source of truth for the PMC roster (it also
-drives the format-specification vote gate). This script renders that data into
-the roster table in `docs/src/community/pmc.md`, between the
-`<!-- BEGIN PMC ROSTER -->` and `<!-- END PMC ROSTER -->` markers.
-
-Usage:
-    python ci/sync_pmc_docs.py            # rewrite pmc.md in place
-    python ci/sync_pmc_docs.py --check    # exit 1 if pmc.md is out of sync
-"""
-
-import argparse
-import pathlib
-import sys
-
-import yaml
-
-COMMUNITY_DIR = pathlib.Path(__file__).resolve().parent.parent / "docs/src/community"
-ROSTER_YAML = COMMUNITY_DIR / "pmc.yaml"
-ROSTER_MD = COMMUNITY_DIR / "pmc.md"
-
-BEGIN_MARKER = "<!-- BEGIN PMC ROSTER -->"
-END_MARKER = "<!-- END PMC ROSTER -->"
-
-COLUMNS = [
-    ("Name", "name"),
-    ("GitHub Handle", "handle"),
-    ("Affiliation", "affiliation"),
-    ("Ecosystem Roles", "ecosystem_roles"),
-]
-
-
-def render_table(members):
-    rows = [
-        [str(member.get(key, "") or "") for _, key in COLUMNS] for member in members
-    ]
-    headers = [title for title, _ in COLUMNS]
-    widths = [
-        max(len(headers[i]), *(len(row[i]) for row in rows))
-        if rows
-        else len(headers[i])
-        for i in range(len(COLUMNS))
-    ]
-
-    def format_row(cells):
-        return (
-            "| "
-            + " | ".join(cell.ljust(widths[i]) for i, cell in enumerate(cells))
-            + " |"
-        )
-
-    lines = [format_row(headers), "|" + "|".join("-" * (w + 2) for w in widths) + "|"]
-    lines.extend(format_row(row) for row in rows)
-    return "\n".join(lines)
-
-
-def build_markdown():
-    data = yaml.safe_load(ROSTER_YAML.read_text())
-    members = data["members"]
-    table = render_table(members)
-    block = f"{BEGIN_MARKER}\n{table}\n{END_MARKER}"
-
-    original = ROSTER_MD.read_text()
-    start = original.find(BEGIN_MARKER)
-    end = original.find(END_MARKER)
-    if start == -1 or end == -1:
-        raise SystemExit(
-            f"Could not find roster markers in {ROSTER_MD}. Expected "
-            f"{BEGIN_MARKER!r} and {END_MARKER!r}."
-        )
-    return original[:start] + block + original[end + len(END_MARKER) :]
-
-
-def main():
-    parser = argparse.ArgumentParser(description=__doc__)
-    parser.add_argument(
-        "--check",
-        action="store_true",
-        help="Exit non-zero if pmc.md is out of sync instead of rewriting it.",
-    )
-    args = parser.parse_args()
-
-    updated = build_markdown()
-    if args.check:
-        if ROSTER_MD.read_text() != updated:
-            print(
-                f"{ROSTER_MD} is out of sync with {ROSTER_YAML}. "
-                "Run `python ci/sync_pmc_docs.py` and commit the result.",
-                file=sys.stderr,
-            )
-            sys.exit(1)
-        print(f"{ROSTER_MD.name} is in sync with {ROSTER_YAML.name}.")
-    else:
-        ROSTER_MD.write_text(updated)
-        print(f"Wrote roster table to {ROSTER_MD}.")
-
-
-if __name__ == "__main__":
-    main()
diff --git a/ci/test_format_vote_gate.py b/ci/test_format_vote_gate.py
new file mode 100644
index 00000000000..4b1b96ece53
--- /dev/null
+++ b/ci/test_format_vote_gate.py
@@ -0,0 +1,87 @@
+"""Unit tests for the format-spec vote gate logic.
+
+Run with: pytest ci/test_format_vote_gate.py
+"""
+
+import pytest
+
+from format_vote_gate import decide_verdict, tally_reviews
+
+HEAD = "sha_head"
+PMC = {"alice", "bob", "carol", "dave"}
+
+
+def is_pmc(login):
+    return login is not None and login.lower() in PMC
+
+
+def review(login, state, commit_id=HEAD):
+    return {"login": login, "state": state, "commit_id": commit_id}
+
+
+def test_counts_distinct_pmc_approvals_on_head_commit():
+    approvals, stale, vetoes = tally_reviews(
+        [
+            review("alice", "APPROVED"),
+            review("bob", "APPROVED"),
+            review("carol", "APPROVED"),
+        ],
+        HEAD,
+        "author",
+        is_pmc,
+    )
+    assert sorted(approvals) == ["alice", "bob", "carol"]
+    assert stale == []
+    assert vetoes == []
+
+
+def test_only_latest_review_per_member_counts():
+    # Alice approved, then later requested changes -> she is a veto, not approval.
+    approvals, _, vetoes = tally_reviews(
+        [review("alice", "APPROVED"), review("alice", "CHANGES_REQUESTED")],
+        HEAD,
+        "author",
+        is_pmc,
+    )
+    assert approvals == []
+    assert vetoes == ["alice"]
+
+
+def test_approvals_on_earlier_commit_are_stale():
+    approvals, stale, _ = tally_reviews(
+        [review("alice", "APPROVED", "old_sha"), review("bob", "APPROVED")],
+        HEAD,
+        "author",
+        is_pmc,
+    )
+    assert approvals == ["bob"]
+    assert stale == ["alice"]
+
+
+def test_ignores_author_non_pmc_and_dismissed():
+    approvals, _, vetoes = tally_reviews(
+        [
+            review("author", "APPROVED"),  # PR author, even if PMC, never counts
+            review("eve", "APPROVED"),  # not on the PMC
+            review("dave", "DISMISSED"),  # withdrawn
+            review("carol", "COMMENTED"),  # a comment is not a vote
+        ],
+        HEAD,
+        "author",
+        is_pmc,
+    )
+    assert approvals == []
+    assert vetoes == []
+
+
+@pytest.mark.parametrize(
+    ("veto_count", "approval_count", "period_elapsed", "expected"),
+    [
+        (1, 5, True, "veto"),  # veto wins even with enough approvals + elapsed
+        (0, 2, True, "insufficient"),
+        (0, 3, False, "waiting_period"),
+        (0, 3, True, "pass"),
+    ],
+)
+def test_decide_verdict_priority(veto_count, approval_count, period_elapsed, expected):
+    assert decide_verdict(veto_count, approval_count, period_elapsed, 3) == expected
diff --git a/docs/hooks/pmc_roster.py b/docs/hooks/pmc_roster.py
new file mode 100644
index 00000000000..3a56daa2b5d
--- /dev/null
+++ b/docs/hooks/pmc_roster.py
@@ -0,0 +1,46 @@
+"""MkDocs hook: render the PMC roster table from `pmc.yaml` at build time.
+
+`docs/src/community/pmc.yaml` is the source of truth for the PMC roster (it also
+drives the format-spec vote gate). The roster page contains the placeholder
+`<!-- PMC_ROSTER_TABLE -->`; this hook expands it into a Markdown table when the
+docs are built, so the table never has to be maintained by hand.
+
+Registered via `hooks:` in `mkdocs.yml`.
+"""
+
+import pathlib
+
+import yaml
+
+PLACEHOLDER = "<!-- PMC_ROSTER_TABLE -->"
+
+COLUMNS = [
+    ("Name", "name"),
+    ("GitHub Handle", "handle"),
+    ("Affiliation", "affiliation"),
+    ("Ecosystem Roles", "ecosystem_roles"),
+]
+
+
+def _render_table(members):
+    headers = [title for title, _ in COLUMNS]
+    rows = [[str(m.get(key, "") or "") for _, key in COLUMNS] for m in members]
+    widths = [
+        max([len(headers[i])] + [len(row[i]) for row in rows])
+        for i in range(len(COLUMNS))
+    ]
+
+    def row(cells):
+        return "| " + " | ".join(c.ljust(widths[i]) for i, c in enumerate(cells)) + " |"
+
+    lines = [row(headers), "|" + "|".join("-" * (w + 2) for w in widths) + "|"]
+    lines.extend(row(r) for r in rows)
+    return "\n".join(lines)
+
+
+def on_page_markdown(markdown, page, config, files):
+    if PLACEHOLDER not in markdown:
+        return markdown
+    roster_path = pathlib.Path(config["docs_dir"]) / "community" / "pmc.yaml"
+    roster = yaml.safe_load(roster_path.read_text())
+    return markdown.replace(PLACEHOLDER, _render_table(roster["members"]))
diff --git a/docs/mkdocs.yml b/docs/mkdocs.yml
index 8144a42e5f5..ff7db4c3ab2 100644
--- a/docs/mkdocs.yml
+++ b/docs/mkdocs.yml
@@ -66,6 +66,9 @@ plugins:
   - mkdocs_protobuf:
       proto_dir: ../protos
 
+hooks:
+  - hooks/pmc_roster.py
+
 extra:
   generator: false
   social:
diff --git a/docs/src/community/pmc.md b/docs/src/community/pmc.md
index 70cb0692def..5088e45d6ae 100644
--- a/docs/src/community/pmc.md
+++ b/docs/src/community/pmc.md
@@ -27,31 +27,9 @@ In addition to the [activities of maintainers](./maintainers.md#activities), PMC
 
 ## Roster
 
-<!-- This table is generated from `pmc.yaml`. Edit that file and run
-     `python ci/sync_pmc_docs.py` to update it; do not edit the table by hand. -->
-<!-- BEGIN PMC ROSTER -->
-| Name            | GitHub Handle   | Affiliation  | Ecosystem Roles                                                                                               |
-|-----------------|-----------------|--------------|---------------------------------------------------------------------------------------------------------------|
-| Yang Cen        | BubbleCal       | LanceDB      | Milvus Contributor                                                                                            |
-| Pablo Delgado   | pablete         | Netflix      |                                                                                                               |
-| Hao Ding        | Xuanwo          | LanceDB      | Apache OpenDAL PMC Chair, Apache Iceberg Committer, Apache Member and [more](https://xuanwo.io/about/)        |
-| Zhaowei Huang   | SaintBacchus    | Alibaba      | Apache Doris Committer                                                                                        |
-| Will Jones      | wjones127       | LanceDB      | Apache Arrow PMC Member, Apache DataFusion PMC Member, Delta Lake Maintainer                                  |
-| Matt Kafonek    | kafonek         | Runway AI    |                                                                                                               |
-| Denny Lee       | dennyglee       | Databricks   | Unity Catalog Maintainer, Delta Lake Maintainer, Apache Spark Contributor, MLflow Contributor                 |
-| Rob Meng        | chebbyChefNEQ   | Jump Trading |                                                                                                               |
-| Dao Mi          | dowjones226     | Netflix      |                                                                                                               |
-| Weston Pace     | westonpace      | LanceDB      | Apache Arrow PMC Member, Substrait SMC Member                                                                 |
-| Calvin Qi       | calvinqi        | Harvey.ai    |                                                                                                               |
-| Prashanth Rao   | prrao87         | LanceDB      |                                                                                                               |
-| Ethan Rosenthal | EthanRosenthal  | Runway AI    |                                                                                                               |
-| Tim Saucer      | timsaucer       | Rerun.io     | Apache DataFusion PMC Member                                                                                  |
-| Chang She       | changhiskhan    | LanceDB      | Pandas Co-Author                                                                                              |
-| Jasmine Wang    | onigiriisabunny | LanceDB      | Alluxio PMC Community Manager                                                                                 |
-| Lei Xu          | eddyxu          | LanceDB      | Apache Hadoop PMC Member                                                                                      |
-| Vino Yang       | yanghua         | Bytedance    | Apache Hudi PMC Member, Apache Kyuubi PMC Member, Apache Kylin Committer, Apache Incubation Program Committer |
-| Jack Ye         | jackye1995      | LanceDB      | Apache Iceberg PMC Member, Apache Polaris (incubating) PPMC Member, Apache Incubation Program Committer       |
-<!-- END PMC ROSTER -->
+<!-- The roster table is generated at build time from `pmc.yaml` by the
+     `hooks/pmc_roster.py` MkDocs hook. Edit `pmc.yaml`, not this placeholder. -->
+<!-- PMC_ROSTER_TABLE -->
 
 ## Becoming a PMC Member
 
diff --git a/docs/src/community/pmc.yaml b/docs/src/community/pmc.yaml
index 673e5d7123d..34819652c00 100644
--- a/docs/src/community/pmc.yaml
+++ b/docs/src/community/pmc.yaml
@@ -1,13 +1,13 @@
 # Source of truth for the Project Management Committee (PMC) roster.
 #
 # This file drives two things, so keep it accurate:
-#   1. The roster table in `pmc.md` (regenerated by `ci/sync_pmc_docs.py`).
+#   1. The roster table in `pmc.md`, rendered at docs build time by the
+#      `docs/hooks/pmc_roster.py` MkDocs hook.
 #   2. The format-specification vote gate, which only counts PR approvals from
 #      the `handle`s listed here (see `.github/workflows/format-vote-gate.yml`).
 #
 # Adding or removing a member is itself a PMC vote (roster change). After the
-# vote passes, edit this file and run `python ci/sync_pmc_docs.py` to update the
-# docs table.
+# vote passes, edit this file; the docs table updates automatically.
 #
 # `handle` must match the member's GitHub login exactly (case-insensitive when
 # matched). `ecosystem_roles` is free-form markdown and may be empty.
diff --git a/docs/src/community/voting.md b/docs/src/community/voting.md
index 338da66790c..875a3029270 100644
--- a/docs/src/community/voting.md
+++ b/docs/src/community/voting.md
@@ -59,9 +59,10 @@ pull request, and the requirement is enforced structurally in CI rather than by
 convention.
 
 A PR is considered a format-specification change when it modifies the protobuf
-definitions (`protos/**/*.proto`) or the spec documentation (`docs/src/format/**`).
-The [format spec vote gate](https://github.com/lance-format/lance/blob/main/.github/workflows/format-vote-gate.yml)
-labels such PRs `format-change` and blocks merging until all of the following hold:
+definitions (`protos/**/*.proto`) or the spec documentation (`docs/src/format/**`);
+such PRs are labelled `format-change` automatically. The
+[format spec vote gate](https://github.com/lance-format/lance/blob/main/.github/workflows/format-vote-gate.yml)
+blocks merging a `format-change` PR until all of the following hold:
 
 - **Three binding +1 votes.** Three PMC members have approved the PR, excluding
   the proposer. Cast +1 by approving the PR. Only approvals on the latest commit
@@ -78,5 +79,5 @@ The PMC roster used to count votes is read from
 [`docs/src/community/pmc.yaml`](./pmc.md).
 
 For a trivial edit that does not change the format — a typo, wording, or
-formatting fix — a PMC member may remove the `format-change` label to waive the
+formatting fix — a PMC member may apply the `format-waived` label to waive the
 vote.