From a2353e6a0346f25a1f623aba3981eb4de923ee10 Mon Sep 17 00:00:00 2001
From: Etienne Pichot Damon <etienne@mobilitydata.org>
Date: Wed, 4 Nov 2026 10:34:28 -0500
Subject: [PATCH] feat(specifications): add change history, adopters chart and
 shared mobility modes

History section on every specification page:
- Read from GitHub's public API in the visitor's browser, so an open pull
  request appears as soon as it is opened, without a site rebuild.
- "Proposed changes": open pull requests touching the entry's file, with
  "Review in progress", who proposed it, the start of the description and a
  Field / Before / Proposed table (vocabulary labels, at most 6 rows).
- "Recent changes": the last 4 changes merged into main, with who proposed
  and who merged them; the field table is folded under "What changed".
  Commits made without a pull request show as "Committed".
- Responses are cached for 10 minutes in sessionStorage and shared between
  pages to stay within the 60 unauthenticated calls per hour. When GitHub
  cannot be reached, the section falls back to a link to the file history.
- Before/after values are compared by parsing both revisions of the file
  with js-yaml 4.1.0 (MIT), vendored under overrides/assets/javascript/vendor
  and loaded only on specification pages.

Known adopters chart in the Adoption section:
- Built at build time from the git history of each data file
  (scripts/spec_history.py). One point per count date; edits that leave the
  count unchanged are ignored.
- Shown only when there are at least 2 points. Time on the x axis, adopters
  from 0 on the y axis, no legend, latest value labelled, exact values on
  hover/focus and in a screen-reader table.
- Without git history (shallow clone) the chart is simply left out.

Modes: add bikeshare, shared_scooter and carsharing to the vocabulary and
data/README.md.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 data/README.md                                |   2 +-
 hooks/specifications.py                       | 157 ++++++-
 overrides/assets/javascript/specifications.js | 426 ++++++++++++++++++
 .../assets/javascript/vendor/js-yaml.LICENSE  |  21 +
 .../assets/javascript/vendor/js-yaml.min.js   |   2 +
 .../assets/stylesheets/specifications.css     | 275 ++++++++++-
 scripts/spec_data.py                          |  10 +-
 scripts/spec_history.py                       | 119 +++++
 8 files changed, 1006 insertions(+), 6 deletions(-)
 create mode 100644 overrides/assets/javascript/vendor/js-yaml.LICENSE
 create mode 100644 overrides/assets/javascript/vendor/js-yaml.min.js
 create mode 100644 scripts/spec_history.py

diff --git a/data/README.md b/data/README.md
index 0745650..f9e865a 100644
--- a/data/README.md
+++ b/data/README.md
@@ -85,7 +85,7 @@ Travel information: Transit schedules, geography, fares.
 | `full_name` | Free text. |
 | `homepage_url` | URL. |
 | `status` | The coalition's overall finding: `compliant`, `partially_compliant`, `not_compliant`, `inactive` or `under_review`. |
-| `modes` | Any of `public_transport`, `microtransit_drt`, `taxi_ridehail`, `bicycle`, `pedestrian_accessibility`, `parking`. Empty shows as "Unclassified". |
+| `modes` | Any of `public_transport`, `microtransit_drt`, `taxi_ridehail`, `bicycle`, `bikeshare`, `shared_scooter`, `carsharing`, `pedestrian_accessibility`, `parking`. Empty shows as "Unclassified". |
 | `maintainers` | Organization ids: file names in `organizations/`. |
 | `licences` | A list of licences, each with an `id` from `licences.csv` and optional `scopes`: `specification`, `documentation`, `code`, `data`. Empty means no licence is stated. |
 | `licence_evidence_url` | URL of the licence text, when it is not the licence's own page. |
diff --git a/hooks/specifications.py b/hooks/specifications.py
index b0d5794..fdfd75d 100644
--- a/hooks/specifications.py
+++ b/hooks/specifications.py
@@ -38,6 +38,7 @@
 
 import spec_api  # noqa: E402  (path set above)
 import spec_data  # noqa: E402
+import spec_history  # noqa: E402
 
 SECTION = "specifications"
 
@@ -642,6 +643,7 @@ def render_detail(spec, data, base):
         sections.append(("adoption", "Adoption", "account-group"))
     if spec["maintainers"]:
         sections.append(("maintainers", "Maintainers", "domain"))
+    sections.append(("history", "History", "history"))
     o.append('<nav class="spec-nav" aria-label="On this page"><ul>')
     for sid, label, ico in sections:
         o.append('<li><a href="#%s">%s<span>%s</span></a></li>' % (sid, icon(ico), escape(label)))
@@ -776,7 +778,12 @@ def render_detail(spec, data, base):
         if spec["adopters_registry"]:
             o.append(dl_row("database-outline", "Adopters registry",
                             ext_link(spec["adopters_registry"], "Open registry")))
-        o.append("</dl></section>")
+        o.append("</dl>")
+        series = spec_history.adopters_series(spec)
+        if len(series) >= 2:
+            o.append('<div class="adopt-hist"><h3>%s<span>History</span></h3>%s</div>'
+                     % (icon("chart-line"), render_adopters_chart(series)))
+        o.append("</section>")
 
     # ---- maintainers
     if spec["maintainers"]:
@@ -809,6 +816,8 @@ def render_detail(spec, data, base):
             o.append("</ul></div>")
         o.append("</section>")
 
+    o.append(render_history(spec, data))
+
     o.append("</div>")  # body
 
     o.append(render_contribute(data, spec))
@@ -817,6 +826,152 @@ def render_detail(spec, data, base):
     return "\n".join(o)
 
 
+def nice_ceiling(value):
+    """A round number a little above `value`, for the top of a chart axis."""
+    import math
+    if value <= 0:
+        return 1
+    target = value * 1.1
+    mag = 10 ** math.floor(math.log10(target))
+    for step in (1, 1.2, 1.5, 2, 2.5, 3, 4, 5, 6, 8, 10):
+        if step * mag >= target:
+            return int(step * mag) if step * mag >= 1 else step * mag
+    return 10 * mag
+
+
+def short_date(iso):
+    import datetime
+    d = datetime.date.fromisoformat(iso)
+    return "%d %s %d" % (d.day, d.strftime("%b"), d.year)
+
+
+def render_adopters_chart(points):
+    """Known adopters over time: one line, time across, count up from zero.
+
+    Deliberately bare: no legend (there is one series and the heading names
+    it), two dates and three values on the axes, and a direct label on the
+    latest count only. Every point carries its exact value and date on hover
+    or focus, and the same numbers are in a table for screen readers.
+
+    The line is drawn in a stretched 100x100 SVG and the dots and labels are
+    HTML placed in percentages on top of it, so the plot fills any width
+    without distorting the dots or the text.
+    """
+    import datetime
+    days = [datetime.date.fromisoformat(p["date"]).toordinal() for p in points]
+    span = max(days[-1] - days[0], 1)
+    top = nice_ceiling(max(p["count"] for p in points))
+    xy = [((d - days[0]) * 100.0 / span, 100 - p["count"] * 100.0 / top)
+          for d, p in zip(days, points)]
+    line = " ".join("%.2f,%.2f" % c for c in xy)
+
+    o = ['<figure class="adopt-chart">']
+    o.append('<div class="adopt-chart__plot">')
+    for value, pos in ((top, 0), (top / 2.0, 50), (0, 100)):
+        o.append('<span class="adopt-chart__y" style="top:%d%%" aria-hidden="true">%s</span>'
+                 % (pos, "{:,}".format(int(value)) if value == int(value) else value))
+    o.append('<svg viewBox="0 0 100 100" preserveAspectRatio="none" aria-hidden="true" '
+             'focusable="false">')
+    for y in (0, 50):
+        o.append('<line class="adopt-chart__grid" x1="0" x2="100" y1="%d" y2="%d" '
+                 'vector-effect="non-scaling-stroke"/>' % (y, y))
+    o.append('<line class="adopt-chart__base" x1="0" x2="100" y1="100" y2="100" '
+             'vector-effect="non-scaling-stroke"/>')
+    o.append('<polygon class="adopt-chart__area" points="0,100 %s 100,100"/>' % line)
+    o.append('<polyline class="adopt-chart__line" points="%s" '
+             'vector-effect="non-scaling-stroke"/>' % line)
+    o.append("</svg>")
+    for n, ((x, y), p) in enumerate(zip(xy, points)):
+        last = n == len(points) - 1
+        tip = "%s adopters, %s" % ("{:,}".format(p["count"]), short_date(p["date"]))
+        o.append('<span class="adopt-chart__dot%s" style="left:%.2f%%;top:%.2f%%" tabindex="0" '
+                 'aria-label="%s"><span class="adopt-chart__tip" aria-hidden="true">%s</span>'
+                 "</span>" % (" is-last" if last else "", x, y, escape(tip), escape(tip)))
+    o.append('<span class="adopt-chart__val" style="left:%.2f%%;top:%.2f%%" aria-hidden="true">'
+             "%s</span>" % (xy[-1][0], xy[-1][1], "{:,}".format(points[-1]["count"])))
+    o.append("</div>")
+    o.append('<div class="adopt-chart__x" aria-hidden="true"><span>%s</span><span>%s</span></div>'
+             % (short_date(points[0]["date"]), short_date(points[-1]["date"])))
+    o.append('<table class="u-sr"><caption>Known adopters over time</caption><thead><tr>'
+             '<th scope="col">Date</th><th scope="col">Known adopters</th></tr></thead><tbody>')
+    for p in points:
+        o.append("<tr><td>%s</td><td>%s</td></tr>"
+                 % (escape(p["date"]), "{:,}".format(p["count"])))
+    o.append("</tbody></table></figure>")
+    return "".join(o)
+
+
+def history_labels(data):
+    """Field names and value labels the History script needs, in one object.
+
+    The script compares two versions of the file as written, so it sees keys
+    joined with dots ("adoption.adopters_count") and ids
+    ("partially_compliant", "mobilitydata"). These are the words the rest of
+    the page uses for the same things.
+    """
+    fields = {
+        "short_name": "Short name",
+        "full_name": "Full name",
+        "homepage_url": "Homepage",
+        "status": "MDIP status",
+        "modes": "Mode",
+        "maintainers": "Maintainers",
+        "licences": "Licence",
+        "licence_evidence_url": "Licence text",
+        "first_release_year": "First release",
+        "adoption.lifecycle": "Lifecycle",
+        "adoption.tier": "Adoption tier",
+        "adoption.adopters_count": "Known adopters",
+        "adoption.adopters_count_updated": "Adopters counted on",
+        "adoption.adopters_registry_url": "Adopters registry",
+        "adoption.confirmed_by_maintainer": "Confirmed by maintainer",
+        "description": "Description",
+    }
+    for c in data["criteria"]:
+        base = "principles.%s." % c["key"]
+        fields[base + "verdict"] = c["label"]
+        fields[base + "rationale"] = "%s: rationale" % c["label"]
+        fields[base + "evidence_url"] = "%s: evidence" % c["label"]
+    values = {
+        "status": dict((k, v["label"]) for k, v in spec_data.STATUS.items()),
+        "verdict": dict((k, v["label"]) for k, v in spec_data.VERDICT.items()),
+        "adoption.lifecycle": dict((k, v["label"]) for k, v in spec_data.LIFECYCLE.items()),
+        "adoption.tier": dict((k, v["label"]) for k, v in spec_data.ADOPTION_TIER.items()),
+        "modes": dict(spec_data.MODES),
+        "maintainers": dict((k, o["name"]) for k, o in data["organizations"].items()),
+    }
+    icons = dict((name, icon(name)) for name in (
+        "source-pull", "source-merge", "source-commit", "plus-circle-outline",
+        "delete-outline", "open-in-new"))
+    return {"fields": fields, "values": values, "icons": icons}
+
+
+def render_history(spec, data):
+    """Recent changes to this entry on GitHub, filled in by the page script.
+
+    The list is read from GitHub's API in the visitor's browser rather than at
+    build time, so a pull request shows up here as soon as it is opened, not
+    at the next deploy. Only the frame is rendered here: the heading, a link
+    to the file's full history (which is all a reader gets without JavaScript
+    or when GitHub cannot be reached), and the labels the script needs.
+    """
+    path = spec["source_path"]
+    commits = "https://github.com/%s/commits/%s/%s" % (
+        spec_data.GITHUB_REPO, spec_data.GITHUB_BRANCH, path)
+    o = ['<section class="spec-section hist" id="history" data-history data-repo="%s" '
+         'data-branch="%s" data-path="%s">'
+         % (escape(spec_data.GITHUB_REPO), escape(spec_data.GITHUB_BRANCH), escape(path))]
+    o.append('<h2 class="spec-h2">%s<span>History</span></h2>' % icon("history"))
+    o.append('<div class="hist__body" data-history-body aria-live="polite">'
+             '<p class="hist__note">Changes to this entry are reviewed on GitHub. '
+             '<a href="%s" rel="noopener">See its full history</a>.</p></div>' % escape(commits))
+    o.append('<p class="hist__foot">%s</p>' % ext_link(commits, "Full history on GitHub"))
+    o.append('<script type="application/json" data-history-labels>%s</script>'
+             % json.dumps(history_labels(data), separators=(",", ":")).replace("</", "<\\/"))
+    o.append("</section>")
+    return "".join(o)
+
+
 SCOPE_LABEL = spec_data.LICENCE_SCOPES
 
 
diff --git a/overrides/assets/javascript/specifications.js b/overrides/assets/javascript/specifications.js
index 68955d0..2a3adb4 100644
--- a/overrides/assets/javascript/specifications.js
+++ b/overrides/assets/javascript/specifications.js
@@ -23,6 +23,10 @@
   var SEP = "::";
   var DEFAULT_SORT = "default";
 
+  /* Where this file is served from, to find vendor/ next to it. Only known
+     while the script first runs. */
+  var SCRIPT_SRC = document.currentScript ? document.currentScript.src : "";
+
   function ready(fn) {
     if (document.readyState !== "loading") { fn(); }
     else { document.addEventListener("DOMContentLoaded", fn); }
@@ -35,6 +39,7 @@
     initStickyOffset();
     initList();
     initDetail();
+    initHistory();
     initDisclosureAnchors();
   });
 
@@ -451,4 +456,425 @@
 
     sections.forEach(function (s) { observer.observe(s); });
   }
+
+  /* -------------------------------------------------------------- history */
+
+  /*
+   * The History section of a specification page, read from GitHub's public
+   * API in the browser so that an open pull request shows up as soon as it
+   * exists, without waiting for the site to be rebuilt.
+   *
+   * Two lists: pull requests still open on this entry's file ("Review in
+   * progress"), then the last MAX_CHANGES changes merged into the branch the
+   * site is built from. What a change did is worked out by reading the file
+   * before and after it (raw.githubusercontent.com, which has no rate limit)
+   * and comparing the two field by field.
+   *
+   * Without a token GitHub allows 60 API calls an hour per visitor, so every
+   * answer is kept in sessionStorage for a few minutes and shared between
+   * specification pages, and the per-commit lookups stop as soon as enough
+   * changes are found. If GitHub cannot be reached, the server-rendered link
+   * to the file's history stays as it is.
+   */
+  var MAX_CHANGES = 4;
+  var MAX_ROWS = 6;
+  var EXCERPT = 180;
+  var CACHE_MS = 10 * 60 * 1000;
+
+  function initHistory() {
+    var root = document.querySelector("[data-history]");
+    var labelsEl = root && root.querySelector("[data-history-labels]");
+    if (!root || !labelsEl || !window.fetch || !window.Promise) { return; }
+
+    var cfg = JSON.parse(labelsEl.textContent);
+    var repo = root.getAttribute("data-repo");
+    var branch = root.getAttribute("data-branch");
+    var path = root.getAttribute("data-path");
+    var body = root.querySelector("[data-history-body]");
+    var api = "https://api.github.com/repos/" + repo;
+    var fallback = body.innerHTML;
+
+    body.innerHTML = '<p class="hist__note">Loading changes from GitHub...</p>';
+
+    Promise.all([loadYaml(), openProposals(api, path), mergedChanges(api, repo, branch, path)])
+      .then(function (res) {
+        var open = res[1];
+        var merged = res[2];
+        return Promise.all([
+          Promise.all(open.map(function (pr) {
+            return diffOf(
+              raw(repo, pr.base, path),
+              raw(pr.headRepo || repo, pr.head, path)
+            ).then(function (d) { pr.diff = d; return pr; });
+          })),
+          Promise.all(merged.map(function (ch) {
+            return diffOf(
+              ch.parent ? raw(repo, ch.parent, path) : Promise.resolve(null),
+              raw(repo, ch.sha, path)
+            ).then(function (d) { ch.diff = d; return ch; });
+          }))
+        ]);
+      })
+      .then(function (lists) {
+        body.innerHTML = render(lists[0], lists[1]);
+      })
+      .catch(function () {
+        body.innerHTML = '<p class="hist__note">Recent changes could not be loaded from GitHub ' +
+          "right now.</p>" + fallback;
+      });
+
+    /* ---- rendering */
+
+    function render(open, merged) {
+      if (!open.length && !merged.length) {
+        return '<p class="hist__note">No change recorded on GitHub yet.</p>';
+      }
+      var h = "";
+      if (open.length) {
+        h += '<h3 class="hist__group">Proposed changes</h3><ol class="hist__list">' +
+          open.map(function (pr) {
+            return item({
+              tone: "info", ico: "source-pull", status: "Review in progress",
+              title: pr.title, number: pr.number, url: pr.url, date: pr.created,
+              people: [["Change proposed by", pr.user]],
+              text: pr.body, diff: pr.diff, after: "Proposed", folded: false
+            });
+          }).join("") + "</ol>";
+      }
+      if (merged.length) {
+        h += '<h3 class="hist__group">Recent changes</h3><ol class="hist__list">' +
+          merged.map(function (ch) {
+            var added = ch.diff && ch.diff.added;
+            return item({
+              tone: added ? "muted" : ch.pr ? "pass" : "muted",
+              ico: added ? "plus-circle-outline" : ch.pr ? "source-merge" : "source-commit",
+              status: added ? "Added to the registry" : ch.pr ? "Merged" : "Committed",
+              title: ch.title, number: ch.pr, url: ch.url, date: ch.date,
+              people: ch.pr
+                ? [["Change proposed by", ch.user], ["Change merged by", ch.mergedBy]]
+                : [["Changed by", ch.user]],
+              text: ch.body, diff: added ? null : ch.diff, after: "After", folded: true
+            });
+          }).join("") + "</ol>";
+      }
+      return h;
+    }
+
+    function item(it) {
+      var h = '<li class="hist__item">';
+      h += '<div class="hist__top"><span class="pill pill--' + it.tone + '">' +
+        cfg.icons[it.ico] + "<span>" + esc(it.status) + "</span></span>";
+      if (it.date) {
+        h += '<time class="hist__date" datetime="' + esc(it.date) + '">' +
+          esc(dateLabel(it.date)) + "</time>";
+      }
+      h += "</div>";
+      h += '<a class="hist__title" href="' + esc(it.url) + '" rel="noopener">' +
+        "<span>" + esc(it.title) + "</span>" +
+        (it.number ? '<span class="hist__num">#' + it.number + "</span>" : "") + "</a>";
+      var people = it.people.filter(function (p) { return p[1]; });
+      if (people.length) {
+        h += '<p class="hist__by">' + people.map(function (p) {
+          return "<span>" + esc(p[0]) + ' <a href="' + esc(p[1].url) + '" rel="noopener">@' +
+            esc(p[1].login) + "</a></span>";
+        }).join("") + "</p>";
+      }
+      var text = excerpt(it.text);
+      if (text) { h += '<p class="hist__desc">' + esc(text) + "</p>"; }
+      if (it.diff && it.diff.removed) {
+        h += '<p class="hist__note">' + cfg.icons["delete-outline"] +
+          " Removes this entry from the registry.</p>";
+      } else if (it.diff && it.diff.rows.length) {
+        var table = diffTable(it.diff.rows, it.after, it.url);
+        h += it.folded
+          ? '<details class="hist__more"><summary>What changed<span class="hist__n">' +
+            it.diff.rows.length + (it.diff.rows.length === 1 ? " field" : " fields") +
+            "</span></summary>" + table + "</details>"
+          : table;
+      }
+      return h + "</li>";
+    }
+
+    function diffTable(rows, after, url) {
+      var shown = rows.slice(0, MAX_ROWS);
+      var h = '<div class="hist__scroll"><table class="hist__t"><thead><tr>' +
+        '<th scope="col">Field</th><th scope="col">Before</th><th scope="col">' +
+        esc(after) + "</th></tr></thead><tbody>";
+      shown.forEach(function (r) {
+        h += '<tr><th scope="row">' + esc(r.label) + "</th>" + cell(r.before, "old") +
+          cell(r.after, "new") + "</tr>";
+      });
+      h += "</tbody></table></div>";
+      if (rows.length > shown.length) {
+        h += '<p class="hist__extra"><a href="' + esc(url) + '" rel="noopener">and ' +
+          (rows.length - shown.length) + " more on GitHub</a></p>";
+      }
+      return h;
+    }
+
+    function cell(value, kind) {
+      if (value === "") { return '<td class="hist__' + kind + ' is-empty">Not set</td>'; }
+      var short = value.length > 90 ? value.slice(0, 88).replace(/\s+\S*$/, "") + "..." : value;
+      return '<td class="hist__' + kind + '"' +
+        (short !== value ? ' title="' + esc(value) + '"' : "") + ">" + esc(short) + "</td>";
+    }
+
+    /* ---- comparing two versions of the file */
+
+    function diffOf(beforeP, afterP) {
+      return Promise.all([beforeP, afterP]).then(function (texts) {
+        if (texts[0] === null && texts[1] === null) { return null; }
+        if (texts[0] === null) { return { added: true, rows: [] }; }
+        if (texts[1] === null) { return { removed: true, rows: [] }; }
+        var a = flatten(texts[0]);
+        var b = flatten(texts[1]);
+        if (!a || !b) { return null; }
+        var keys = Object.keys(cfg.fields).filter(function (k) { return k in a || k in b; });
+        Object.keys(a).concat(Object.keys(b)).forEach(function (k) {
+          if (keys.indexOf(k) < 0) { keys.push(k); }
+        });
+        var rows = [];
+        keys.forEach(function (k) {
+          var x = show(k, a[k]);
+          var y = show(k, b[k]);
+          if (x !== y) { rows.push({ label: cfg.fields[k] || k, before: x, after: y }); }
+        });
+        return { rows: rows };
+      });
+    }
+
+    /* The file's fields as { "dotted.path": value }, plus its description. */
+    function flatten(text) {
+      text = text.replace(/\r\n/g, "\n");
+      var m = /^---\n([\s\S]*?)\n---\n?([\s\S]*)$/.exec(text);
+      if (!m) { return null; }
+      var front;
+      try { front = window.jsyaml.load(m[1], { schema: window.jsyaml.CORE_SCHEMA }) || {}; }
+      catch (e) { return null; }
+      var out = {};
+      Object.keys(front).forEach(function (k) {
+        var v = front[k];
+        if (k === "adoption" && isObj(v)) {
+          Object.keys(v).forEach(function (j) { out[k + "." + j] = v[j]; });
+        } else if (k === "principles" && isObj(v)) {
+          Object.keys(v).forEach(function (p) {
+            if (!isObj(v[p])) { return; }
+            Object.keys(v[p]).forEach(function (j) {
+              out["principles." + p + "." + j] = v[p][j];
+            });
+          });
+        } else if (k === "licences" && Array.isArray(v)) {
+          out[k] = v.map(function (l) {
+            if (!isObj(l)) { return String(l); }
+            var scopes = [].concat(l.scopes || []);
+            return l.id + (scopes.length ? " (" + scopes.join(", ") + ")" : "");
+          });
+        } else {
+          out[k] = v;
+        }
+      });
+      var d = /^#\s+Description\s*$([\s\S]*?)(?=^#\s|$(?![\s\S]))/m.exec(m[2]);
+      out.description = d ? d[1].trim() : "";
+      return out;
+    }
+
+    /* One value as the page words it: vocabulary labels, Yes/No, numbers. */
+    function show(key, v) {
+      if (v === undefined || v === null || v === "") { return ""; }
+      var vocab = cfg.values[/^principles\..+\.verdict$/.test(key) ? "verdict" : key];
+      var one = function (x) {
+        if (x === true) { return "Yes"; }
+        if (x === false) { return "No"; }
+        if (typeof x === "number" && key !== "first_release_year") {
+          return x.toLocaleString("en-US");
+        }
+        if (isObj(x)) { return JSON.stringify(x); }
+        return vocab && vocab[x] ? vocab[x] : String(x);
+      };
+      return Array.isArray(v) ? v.map(one).join(", ") : one(v);
+    }
+  }
+
+  /* ---- what GitHub knows */
+
+  function openProposals(api, path) {
+    return getJSON(api + "/pulls?state=open&per_page=100", function (list) {
+      return list.map(function (p) {
+        return {
+          number: p.number, title: p.title, url: p.html_url, body: p.body || "",
+          created: p.created_at, user: person(p.user), base: p.base.sha, head: p.head.sha,
+          headRepo: p.head.repo ? p.head.repo.full_name : null
+        };
+      });
+    }).then(function (prs) {
+      return Promise.all(prs.slice(0, 40).map(function (pr) {
+        return getJSON(api + "/pulls/" + pr.number + "/files?per_page=100", function (files) {
+          return files.map(function (f) { return [f.filename, f.previous_filename || ""]; });
+        }, pr.head).then(function (files) {
+          var touches = files.some(function (f) { return f[0] === path || f[1] === path; });
+          return touches ? pr : null;
+        });
+      }));
+    }).then(function (prs) { return prs.filter(Boolean); });
+  }
+
+  /*
+   * The latest changes on the branch, one per pull request. A squash merge
+   * names its pull request in the message ("Title (#12)"), as does a merge
+   * commit; any other commit is looked up once to find whether it came in
+   * through a pull request at all. Commits of the same pull request are
+   * grouped, and the file before the oldest of them is the "before" side.
+   */
+  function mergedChanges(api, repo, branch, path) {
+    var url = api + "/commits?sha=" + encodeURIComponent(branch) + "&path=" +
+      encodeURIComponent(path) + "&per_page=30";
+    return getJSON(url, function (list) {
+      return list.map(function (c) {
+        return {
+          sha: c.sha, url: c.html_url, date: c.commit.committer.date,
+          message: c.commit.message, user: person(c.author),
+          parent: c.parents.length ? c.parents[0].sha : null
+        };
+      });
+    }).then(function (commits) {
+      var changes = [];
+      var byPr = {};
+      var lookups = 0;
+
+      function step(i) {
+        if (i >= commits.length) { return Promise.resolve(); }
+        var c = commits[i];
+        var first = c.message.split("\n")[0];
+        var m = /\(#(\d+)\)\s*$/.exec(first) || /^Merge pull request #(\d+)/.exec(first);
+        var found = m ? Promise.resolve(Number(m[1]))
+          : lookups++ < 8
+            ? getJSON(api + "/commits/" + c.sha + "/pulls", function (prs) {
+              var pr = prs.filter(function (p) { return p.merged_at; })[0];
+              return pr ? pr.number : 0;
+            }).catch(function () { return 0; })
+            : Promise.resolve(0);
+        return found.then(function (num) {
+          if (num && byPr[num]) {
+            byPr[num].parent = c.parent;       // older commit of the same PR
+          } else {
+            if (changes.length === MAX_CHANGES) { return; }
+            var ch = {
+              sha: c.sha, parent: c.parent, pr: num || 0, url: c.url, date: c.date,
+              title: first, body: c.message.split("\n").slice(1).join("\n"), user: c.user
+            };
+            changes.push(ch);
+            if (num) { byPr[num] = ch; }
+          }
+          return step(i + 1);
+        });
+      }
+
+      return step(0).then(function () {
+        return Promise.all(changes.map(function (ch) {
+          if (!ch.pr) { return ch; }
+          return getJSON(api + "/pulls/" + ch.pr, function (p) {
+            return {
+              title: p.title, url: p.html_url, body: p.body || "", user: person(p.user),
+              mergedBy: person(p.merged_by), merged: p.merged_at
+            };
+          }).then(function (p) {
+            ch.title = p.title;
+            ch.url = p.url;
+            ch.body = p.body;
+            ch.user = p.user;
+            ch.mergedBy = p.mergedBy;
+            ch.date = p.merged || ch.date;
+            return ch;
+          }, function () { return ch; });
+        }));
+      });
+    });
+  }
+
+  function person(u) {
+    return u && u.login ? { login: u.login, url: u.html_url } : null;
+  }
+
+  /* A file at one commit, or null where it does not exist there. Commits
+     never change, so the answer is kept for the whole session. */
+  var RAW = {};
+  function raw(repo, sha, path) {
+    var url = "https://raw.githubusercontent.com/" + repo + "/" + sha + "/" +
+      path.split("/").map(encodeURIComponent).join("/");
+    if (!RAW[url]) {
+      RAW[url] = fetch(url).then(function (r) {
+        if (r.status === 404) { return null; }
+        if (!r.ok) { throw new Error("HTTP " + r.status); }
+        return r.text();
+      });
+    }
+    return RAW[url];
+  }
+
+  /* GET from the API, keep only what `pick` returns, and remember it for
+     CACHE_MS. `version` invalidates an entry early (a pull request's head). */
+  function getJSON(url, pick, version) {
+    var key = "mdip-gh:" + url + (version ? "@" + version : "");
+    try {
+      var hit = JSON.parse(sessionStorage.getItem(key));
+      if (hit && Date.now() - hit.t < CACHE_MS) { return Promise.resolve(hit.v); }
+    } catch (e) { /* storage off or full: fetch */ }
+    return fetch(url, { headers: { Accept: "application/vnd.github+json" } })
+      .then(function (r) {
+        if (!r.ok) { throw new Error("HTTP " + r.status); }
+        return r.json();
+      })
+      .then(function (json) {
+        var v = pick(json);
+        try { sessionStorage.setItem(key, JSON.stringify({ t: Date.now(), v: v })); }
+        catch (e) { /* not cached, still shown */ }
+        return v;
+      });
+  }
+
+  /* js-yaml, served next to this script, loaded only on pages that need it. */
+  var yamlLoad = null;
+  function loadYaml() {
+    if (window.jsyaml) { return Promise.resolve(); }
+    if (!yamlLoad) {
+      yamlLoad = new Promise(function (resolve, reject) {
+        var s = document.createElement("script");
+        s.src = SCRIPT_SRC.replace(/[^/]*$/, "") + "vendor/js-yaml.min.js";
+        s.onload = resolve;
+        s.onerror = reject;
+        document.head.appendChild(s);
+      });
+    }
+    return yamlLoad;
+  }
+
+  /* The first lines of a pull request description, as plain text: headings
+     ("## Summary") and list bullets are template scaffolding, not content. */
+  function excerpt(text) {
+    var t = (text || "")
+      .replace(/<!--[\s\S]*?-->/g, " ")
+      .replace(/^\s*#+\s.*$/gm, " ")
+      .replace(/^\s*(?:[-*+]|\d+\.)\s+/gm, " ")
+      .replace(/!?\[([^\]]*)\]\([^)]*\)/g, "$1")
+      .replace(/[*`]+/g, "")
+      .replace(/^\s*>\s?/gm, " ")
+      .replace(/\s+/g, " ")
+      .trim();
+    if (t.length <= EXCERPT) { return t; }
+    return t.slice(0, EXCERPT).replace(/\s+\S*$/, "").replace(/[\s.,;:-]+$/, "") + "...";
+  }
+
+  function dateLabel(iso) {
+    var d = new Date(iso);
+    if (isNaN(d)) { return iso; }
+    return d.toLocaleDateString("en-GB", { day: "numeric", month: "short", year: "numeric" });
+  }
+
+  function isObj(v) { return v && typeof v === "object" && !Array.isArray(v); }
+
+  function esc(s) {
+    return String(s === undefined || s === null ? "" : s)
+      .replace(/&/g, "&amp;").replace(/</g, "&lt;").replace(/>/g, "&gt;")
+      .replace(/"/g, "&quot;");
+  }
 })();
diff --git a/overrides/assets/javascript/vendor/js-yaml.LICENSE b/overrides/assets/javascript/vendor/js-yaml.LICENSE
new file mode 100644
index 0000000..09d3a29
--- /dev/null
+++ b/overrides/assets/javascript/vendor/js-yaml.LICENSE
@@ -0,0 +1,21 @@
+(The MIT License)
+
+Copyright (C) 2011-2015 by Vitaly Puzrin
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
diff --git a/overrides/assets/javascript/vendor/js-yaml.min.js b/overrides/assets/javascript/vendor/js-yaml.min.js
new file mode 100644
index 0000000..bdd8eef
--- /dev/null
+++ b/overrides/assets/javascript/vendor/js-yaml.min.js
@@ -0,0 +1,2 @@
+/*! js-yaml 4.1.0 https://github.com/nodeca/js-yaml @license MIT */
+!function(e,t){"object"==typeof exports&&"undefined"!=typeof module?t(exports):"function"==typeof define&&define.amd?define(["exports"],t):t((e="undefined"!=typeof globalThis?globalThis:e||self).jsyaml={})}(this,(function(e){"use strict";function t(e){return null==e}var n={isNothing:t,isObject:function(e){return"object"==typeof e&&null!==e},toArray:function(e){return Array.isArray(e)?e:t(e)?[]:[e]},repeat:function(e,t){var n,i="";for(n=0;n<t;n+=1)i+=e;return i},isNegativeZero:function(e){return 0===e&&Number.NEGATIVE_INFINITY===1/e},extend:function(e,t){var n,i,r,o;if(t)for(n=0,i=(o=Object.keys(t)).length;n<i;n+=1)e[r=o[n]]=t[r];return e}};function i(e,t){var n="",i=e.reason||"(unknown reason)";return e.mark?(e.mark.name&&(n+='in "'+e.mark.name+'" '),n+="("+(e.mark.line+1)+":"+(e.mark.column+1)+")",!t&&e.mark.snippet&&(n+="\n\n"+e.mark.snippet),i+" "+n):i}function r(e,t){Error.call(this),this.name="YAMLException",this.reason=e,this.mark=t,this.message=i(this,!1),Error.captureStackTrace?Error.captureStackTrace(this,this.constructor):this.stack=(new Error).stack||""}r.prototype=Object.create(Error.prototype),r.prototype.constructor=r,r.prototype.toString=function(e){return this.name+": "+i(this,e)};var o=r;function a(e,t,n,i,r){var o="",a="",l=Math.floor(r/2)-1;return i-t>l&&(t=i-l+(o=" ... ").length),n-i>l&&(n=i+l-(a=" ...").length),{str:o+e.slice(t,n).replace(/\t/g,"→")+a,pos:i-t+o.length}}function l(e,t){return n.repeat(" ",t-e.length)+e}var c=function(e,t){if(t=Object.create(t||null),!e.buffer)return null;t.maxLength||(t.maxLength=79),"number"!=typeof t.indent&&(t.indent=1),"number"!=typeof t.linesBefore&&(t.linesBefore=3),"number"!=typeof t.linesAfter&&(t.linesAfter=2);for(var i,r=/\r?\n|\r|\0/g,o=[0],c=[],s=-1;i=r.exec(e.buffer);)c.push(i.index),o.push(i.index+i[0].length),e.position<=i.index&&s<0&&(s=o.length-2);s<0&&(s=o.length-1);var u,p,f="",d=Math.min(e.line+t.linesAfter,c.length).toString().length,h=t.maxLength-(t.indent+d+3);for(u=1;u<=t.linesBefore&&!(s-u<0);u++)p=a(e.buffer,o[s-u],c[s-u],e.position-(o[s]-o[s-u]),h),f=n.repeat(" ",t.indent)+l((e.line-u+1).toString(),d)+" | "+p.str+"\n"+f;for(p=a(e.buffer,o[s],c[s],e.position,h),f+=n.repeat(" ",t.indent)+l((e.line+1).toString(),d)+" | "+p.str+"\n",f+=n.repeat("-",t.indent+d+3+p.pos)+"^\n",u=1;u<=t.linesAfter&&!(s+u>=c.length);u++)p=a(e.buffer,o[s+u],c[s+u],e.position-(o[s]-o[s+u]),h),f+=n.repeat(" ",t.indent)+l((e.line+u+1).toString(),d)+" | "+p.str+"\n";return f.replace(/\n$/,"")},s=["kind","multi","resolve","construct","instanceOf","predicate","represent","representName","defaultStyle","styleAliases"],u=["scalar","sequence","mapping"];var p=function(e,t){if(t=t||{},Object.keys(t).forEach((function(t){if(-1===s.indexOf(t))throw new o('Unknown option "'+t+'" is met in definition of "'+e+'" YAML type.')})),this.options=t,this.tag=e,this.kind=t.kind||null,this.resolve=t.resolve||function(){return!0},this.construct=t.construct||function(e){return e},this.instanceOf=t.instanceOf||null,this.predicate=t.predicate||null,this.represent=t.represent||null,this.representName=t.representName||null,this.defaultStyle=t.defaultStyle||null,this.multi=t.multi||!1,this.styleAliases=function(e){var t={};return null!==e&&Object.keys(e).forEach((function(n){e[n].forEach((function(e){t[String(e)]=n}))})),t}(t.styleAliases||null),-1===u.indexOf(this.kind))throw new o('Unknown kind "'+this.kind+'" is specified for "'+e+'" YAML type.')};function f(e,t){var n=[];return e[t].forEach((function(e){var t=n.length;n.forEach((function(n,i){n.tag===e.tag&&n.kind===e.kind&&n.multi===e.multi&&(t=i)})),n[t]=e})),n}function d(e){return this.extend(e)}d.prototype.extend=function(e){var t=[],n=[];if(e instanceof p)n.push(e);else if(Array.isArray(e))n=n.concat(e);else{if(!e||!Array.isArray(e.implicit)&&!Array.isArray(e.explicit))throw new o("Schema.extend argument should be a Type, [ Type ], or a schema definition ({ implicit: [...], explicit: [...] })");e.implicit&&(t=t.concat(e.implicit)),e.explicit&&(n=n.concat(e.explicit))}t.forEach((function(e){if(!(e instanceof p))throw new o("Specified list of YAML types (or a single Type object) contains a non-Type object.");if(e.loadKind&&"scalar"!==e.loadKind)throw new o("There is a non-scalar type in the implicit list of a schema. Implicit resolving of such types is not supported.");if(e.multi)throw new o("There is a multi type in the implicit list of a schema. Multi tags can only be listed as explicit.")})),n.forEach((function(e){if(!(e instanceof p))throw new o("Specified list of YAML types (or a single Type object) contains a non-Type object.")}));var i=Object.create(d.prototype);return i.implicit=(this.implicit||[]).concat(t),i.explicit=(this.explicit||[]).concat(n),i.compiledImplicit=f(i,"implicit"),i.compiledExplicit=f(i,"explicit"),i.compiledTypeMap=function(){var e,t,n={scalar:{},sequence:{},mapping:{},fallback:{},multi:{scalar:[],sequence:[],mapping:[],fallback:[]}};function i(e){e.multi?(n.multi[e.kind].push(e),n.multi.fallback.push(e)):n[e.kind][e.tag]=n.fallback[e.tag]=e}for(e=0,t=arguments.length;e<t;e+=1)arguments[e].forEach(i);return n}(i.compiledImplicit,i.compiledExplicit),i};var h=d,g=new p("tag:yaml.org,2002:str",{kind:"scalar",construct:function(e){return null!==e?e:""}}),m=new p("tag:yaml.org,2002:seq",{kind:"sequence",construct:function(e){return null!==e?e:[]}}),y=new p("tag:yaml.org,2002:map",{kind:"mapping",construct:function(e){return null!==e?e:{}}}),b=new h({explicit:[g,m,y]});var A=new p("tag:yaml.org,2002:null",{kind:"scalar",resolve:function(e){if(null===e)return!0;var t=e.length;return 1===t&&"~"===e||4===t&&("null"===e||"Null"===e||"NULL"===e)},construct:function(){return null},predicate:function(e){return null===e},represent:{canonical:function(){return"~"},lowercase:function(){return"null"},uppercase:function(){return"NULL"},camelcase:function(){return"Null"},empty:function(){return""}},defaultStyle:"lowercase"});var v=new p("tag:yaml.org,2002:bool",{kind:"scalar",resolve:function(e){if(null===e)return!1;var t=e.length;return 4===t&&("true"===e||"True"===e||"TRUE"===e)||5===t&&("false"===e||"False"===e||"FALSE"===e)},construct:function(e){return"true"===e||"True"===e||"TRUE"===e},predicate:function(e){return"[object Boolean]"===Object.prototype.toString.call(e)},represent:{lowercase:function(e){return e?"true":"false"},uppercase:function(e){return e?"TRUE":"FALSE"},camelcase:function(e){return e?"True":"False"}},defaultStyle:"lowercase"});function w(e){return 48<=e&&e<=55}function k(e){return 48<=e&&e<=57}var C=new p("tag:yaml.org,2002:int",{kind:"scalar",resolve:function(e){if(null===e)return!1;var t,n,i=e.length,r=0,o=!1;if(!i)return!1;if("-"!==(t=e[r])&&"+"!==t||(t=e[++r]),"0"===t){if(r+1===i)return!0;if("b"===(t=e[++r])){for(r++;r<i;r++)if("_"!==(t=e[r])){if("0"!==t&&"1"!==t)return!1;o=!0}return o&&"_"!==t}if("x"===t){for(r++;r<i;r++)if("_"!==(t=e[r])){if(!(48<=(n=e.charCodeAt(r))&&n<=57||65<=n&&n<=70||97<=n&&n<=102))return!1;o=!0}return o&&"_"!==t}if("o"===t){for(r++;r<i;r++)if("_"!==(t=e[r])){if(!w(e.charCodeAt(r)))return!1;o=!0}return o&&"_"!==t}}if("_"===t)return!1;for(;r<i;r++)if("_"!==(t=e[r])){if(!k(e.charCodeAt(r)))return!1;o=!0}return!(!o||"_"===t)},construct:function(e){var t,n=e,i=1;if(-1!==n.indexOf("_")&&(n=n.replace(/_/g,"")),"-"!==(t=n[0])&&"+"!==t||("-"===t&&(i=-1),t=(n=n.slice(1))[0]),"0"===n)return 0;if("0"===t){if("b"===n[1])return i*parseInt(n.slice(2),2);if("x"===n[1])return i*parseInt(n.slice(2),16);if("o"===n[1])return i*parseInt(n.slice(2),8)}return i*parseInt(n,10)},predicate:function(e){return"[object Number]"===Object.prototype.toString.call(e)&&e%1==0&&!n.isNegativeZero(e)},represent:{binary:function(e){return e>=0?"0b"+e.toString(2):"-0b"+e.toString(2).slice(1)},octal:function(e){return e>=0?"0o"+e.toString(8):"-0o"+e.toString(8).slice(1)},decimal:function(e){return e.toString(10)},hexadecimal:function(e){return e>=0?"0x"+e.toString(16).toUpperCase():"-0x"+e.toString(16).toUpperCase().slice(1)}},defaultStyle:"decimal",styleAliases:{binary:[2,"bin"],octal:[8,"oct"],decimal:[10,"dec"],hexadecimal:[16,"hex"]}}),x=new RegExp("^(?:[-+]?(?:[0-9][0-9_]*)(?:\\.[0-9_]*)?(?:[eE][-+]?[0-9]+)?|\\.[0-9_]+(?:[eE][-+]?[0-9]+)?|[-+]?\\.(?:inf|Inf|INF)|\\.(?:nan|NaN|NAN))$");var I=/^[-+]?[0-9]+e/;var S=new p("tag:yaml.org,2002:float",{kind:"scalar",resolve:function(e){return null!==e&&!(!x.test(e)||"_"===e[e.length-1])},construct:function(e){var t,n;return n="-"===(t=e.replace(/_/g,"").toLowerCase())[0]?-1:1,"+-".indexOf(t[0])>=0&&(t=t.slice(1)),".inf"===t?1===n?Number.POSITIVE_INFINITY:Number.NEGATIVE_INFINITY:".nan"===t?NaN:n*parseFloat(t,10)},predicate:function(e){return"[object Number]"===Object.prototype.toString.call(e)&&(e%1!=0||n.isNegativeZero(e))},represent:function(e,t){var i;if(isNaN(e))switch(t){case"lowercase":return".nan";case"uppercase":return".NAN";case"camelcase":return".NaN"}else if(Number.POSITIVE_INFINITY===e)switch(t){case"lowercase":return".inf";case"uppercase":return".INF";case"camelcase":return".Inf"}else if(Number.NEGATIVE_INFINITY===e)switch(t){case"lowercase":return"-.inf";case"uppercase":return"-.INF";case"camelcase":return"-.Inf"}else if(n.isNegativeZero(e))return"-0.0";return i=e.toString(10),I.test(i)?i.replace("e",".e"):i},defaultStyle:"lowercase"}),O=b.extend({implicit:[A,v,C,S]}),j=O,T=new RegExp("^([0-9][0-9][0-9][0-9])-([0-9][0-9])-([0-9][0-9])$"),N=new RegExp("^([0-9][0-9][0-9][0-9])-([0-9][0-9]?)-([0-9][0-9]?)(?:[Tt]|[ \\t]+)([0-9][0-9]?):([0-9][0-9]):([0-9][0-9])(?:\\.([0-9]*))?(?:[ \\t]*(Z|([-+])([0-9][0-9]?)(?::([0-9][0-9]))?))?$");var F=new p("tag:yaml.org,2002:timestamp",{kind:"scalar",resolve:function(e){return null!==e&&(null!==T.exec(e)||null!==N.exec(e))},construct:function(e){var t,n,i,r,o,a,l,c,s=0,u=null;if(null===(t=T.exec(e))&&(t=N.exec(e)),null===t)throw new Error("Date resolve error");if(n=+t[1],i=+t[2]-1,r=+t[3],!t[4])return new Date(Date.UTC(n,i,r));if(o=+t[4],a=+t[5],l=+t[6],t[7]){for(s=t[7].slice(0,3);s.length<3;)s+="0";s=+s}return t[9]&&(u=6e4*(60*+t[10]+ +(t[11]||0)),"-"===t[9]&&(u=-u)),c=new Date(Date.UTC(n,i,r,o,a,l,s)),u&&c.setTime(c.getTime()-u),c},instanceOf:Date,represent:function(e){return e.toISOString()}});var E=new p("tag:yaml.org,2002:merge",{kind:"scalar",resolve:function(e){return"<<"===e||null===e}}),M="ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/=\n\r";var L=new p("tag:yaml.org,2002:binary",{kind:"scalar",resolve:function(e){if(null===e)return!1;var t,n,i=0,r=e.length,o=M;for(n=0;n<r;n++)if(!((t=o.indexOf(e.charAt(n)))>64)){if(t<0)return!1;i+=6}return i%8==0},construct:function(e){var t,n,i=e.replace(/[\r\n=]/g,""),r=i.length,o=M,a=0,l=[];for(t=0;t<r;t++)t%4==0&&t&&(l.push(a>>16&255),l.push(a>>8&255),l.push(255&a)),a=a<<6|o.indexOf(i.charAt(t));return 0===(n=r%4*6)?(l.push(a>>16&255),l.push(a>>8&255),l.push(255&a)):18===n?(l.push(a>>10&255),l.push(a>>2&255)):12===n&&l.push(a>>4&255),new Uint8Array(l)},predicate:function(e){return"[object Uint8Array]"===Object.prototype.toString.call(e)},represent:function(e){var t,n,i="",r=0,o=e.length,a=M;for(t=0;t<o;t++)t%3==0&&t&&(i+=a[r>>18&63],i+=a[r>>12&63],i+=a[r>>6&63],i+=a[63&r]),r=(r<<8)+e[t];return 0===(n=o%3)?(i+=a[r>>18&63],i+=a[r>>12&63],i+=a[r>>6&63],i+=a[63&r]):2===n?(i+=a[r>>10&63],i+=a[r>>4&63],i+=a[r<<2&63],i+=a[64]):1===n&&(i+=a[r>>2&63],i+=a[r<<4&63],i+=a[64],i+=a[64]),i}}),_=Object.prototype.hasOwnProperty,D=Object.prototype.toString;var U=new p("tag:yaml.org,2002:omap",{kind:"sequence",resolve:function(e){if(null===e)return!0;var t,n,i,r,o,a=[],l=e;for(t=0,n=l.length;t<n;t+=1){if(i=l[t],o=!1,"[object Object]"!==D.call(i))return!1;for(r in i)if(_.call(i,r)){if(o)return!1;o=!0}if(!o)return!1;if(-1!==a.indexOf(r))return!1;a.push(r)}return!0},construct:function(e){return null!==e?e:[]}}),q=Object.prototype.toString;var Y=new p("tag:yaml.org,2002:pairs",{kind:"sequence",resolve:function(e){if(null===e)return!0;var t,n,i,r,o,a=e;for(o=new Array(a.length),t=0,n=a.length;t<n;t+=1){if(i=a[t],"[object Object]"!==q.call(i))return!1;if(1!==(r=Object.keys(i)).length)return!1;o[t]=[r[0],i[r[0]]]}return!0},construct:function(e){if(null===e)return[];var t,n,i,r,o,a=e;for(o=new Array(a.length),t=0,n=a.length;t<n;t+=1)i=a[t],r=Object.keys(i),o[t]=[r[0],i[r[0]]];return o}}),R=Object.prototype.hasOwnProperty;var B=new p("tag:yaml.org,2002:set",{kind:"mapping",resolve:function(e){if(null===e)return!0;var t,n=e;for(t in n)if(R.call(n,t)&&null!==n[t])return!1;return!0},construct:function(e){return null!==e?e:{}}}),K=j.extend({implicit:[F,E],explicit:[L,U,Y,B]}),P=Object.prototype.hasOwnProperty,W=/[\x00-\x08\x0B\x0C\x0E-\x1F\x7F-\x84\x86-\x9F\uFFFE\uFFFF]|[\uD800-\uDBFF](?![\uDC00-\uDFFF])|(?:[^\uD800-\uDBFF]|^)[\uDC00-\uDFFF]/,H=/[\x85\u2028\u2029]/,$=/[,\[\]\{\}]/,G=/^(?:!|!!|![a-z\-]+!)$/i,V=/^(?:!|[^,\[\]\{\}])(?:%[0-9a-f]{2}|[0-9a-z\-#;\/\?:@&=\+\$,_\.!~\*'\(\)\[\]])*$/i;function Z(e){return Object.prototype.toString.call(e)}function J(e){return 10===e||13===e}function Q(e){return 9===e||32===e}function z(e){return 9===e||32===e||10===e||13===e}function X(e){return 44===e||91===e||93===e||123===e||125===e}function ee(e){var t;return 48<=e&&e<=57?e-48:97<=(t=32|e)&&t<=102?t-97+10:-1}function te(e){return 48===e?"\0":97===e?"":98===e?"\b":116===e||9===e?"\t":110===e?"\n":118===e?"\v":102===e?"\f":114===e?"\r":101===e?"":32===e?" ":34===e?'"':47===e?"/":92===e?"\\":78===e?"…":95===e?" ":76===e?"\u2028":80===e?"\u2029":""}function ne(e){return e<=65535?String.fromCharCode(e):String.fromCharCode(55296+(e-65536>>10),56320+(e-65536&1023))}for(var ie=new Array(256),re=new Array(256),oe=0;oe<256;oe++)ie[oe]=te(oe)?1:0,re[oe]=te(oe);function ae(e,t){this.input=e,this.filename=t.filename||null,this.schema=t.schema||K,this.onWarning=t.onWarning||null,this.legacy=t.legacy||!1,this.json=t.json||!1,this.listener=t.listener||null,this.implicitTypes=this.schema.compiledImplicit,this.typeMap=this.schema.compiledTypeMap,this.length=e.length,this.position=0,this.line=0,this.lineStart=0,this.lineIndent=0,this.firstTabInLine=-1,this.documents=[]}function le(e,t){var n={name:e.filename,buffer:e.input.slice(0,-1),position:e.position,line:e.line,column:e.position-e.lineStart};return n.snippet=c(n),new o(t,n)}function ce(e,t){throw le(e,t)}function se(e,t){e.onWarning&&e.onWarning.call(null,le(e,t))}var ue={YAML:function(e,t,n){var i,r,o;null!==e.version&&ce(e,"duplication of %YAML directive"),1!==n.length&&ce(e,"YAML directive accepts exactly one argument"),null===(i=/^([0-9]+)\.([0-9]+)$/.exec(n[0]))&&ce(e,"ill-formed argument of the YAML directive"),r=parseInt(i[1],10),o=parseInt(i[2],10),1!==r&&ce(e,"unacceptable YAML version of the document"),e.version=n[0],e.checkLineBreaks=o<2,1!==o&&2!==o&&se(e,"unsupported YAML version of the document")},TAG:function(e,t,n){var i,r;2!==n.length&&ce(e,"TAG directive accepts exactly two arguments"),i=n[0],r=n[1],G.test(i)||ce(e,"ill-formed tag handle (first argument) of the TAG directive"),P.call(e.tagMap,i)&&ce(e,'there is a previously declared suffix for "'+i+'" tag handle'),V.test(r)||ce(e,"ill-formed tag prefix (second argument) of the TAG directive");try{r=decodeURIComponent(r)}catch(t){ce(e,"tag prefix is malformed: "+r)}e.tagMap[i]=r}};function pe(e,t,n,i){var r,o,a,l;if(t<n){if(l=e.input.slice(t,n),i)for(r=0,o=l.length;r<o;r+=1)9===(a=l.charCodeAt(r))||32<=a&&a<=1114111||ce(e,"expected valid JSON character");else W.test(l)&&ce(e,"the stream contains non-printable characters");e.result+=l}}function fe(e,t,i,r){var o,a,l,c;for(n.isObject(i)||ce(e,"cannot merge mappings; the provided source object is unacceptable"),l=0,c=(o=Object.keys(i)).length;l<c;l+=1)a=o[l],P.call(t,a)||(t[a]=i[a],r[a]=!0)}function de(e,t,n,i,r,o,a,l,c){var s,u;if(Array.isArray(r))for(s=0,u=(r=Array.prototype.slice.call(r)).length;s<u;s+=1)Array.isArray(r[s])&&ce(e,"nested arrays are not supported inside keys"),"object"==typeof r&&"[object Object]"===Z(r[s])&&(r[s]="[object Object]");if("object"==typeof r&&"[object Object]"===Z(r)&&(r="[object Object]"),r=String(r),null===t&&(t={}),"tag:yaml.org,2002:merge"===i)if(Array.isArray(o))for(s=0,u=o.length;s<u;s+=1)fe(e,t,o[s],n);else fe(e,t,o,n);else e.json||P.call(n,r)||!P.call(t,r)||(e.line=a||e.line,e.lineStart=l||e.lineStart,e.position=c||e.position,ce(e,"duplicated mapping key")),"__proto__"===r?Object.defineProperty(t,r,{configurable:!0,enumerable:!0,writable:!0,value:o}):t[r]=o,delete n[r];return t}function he(e){var t;10===(t=e.input.charCodeAt(e.position))?e.position++:13===t?(e.position++,10===e.input.charCodeAt(e.position)&&e.position++):ce(e,"a line break is expected"),e.line+=1,e.lineStart=e.position,e.firstTabInLine=-1}function ge(e,t,n){for(var i=0,r=e.input.charCodeAt(e.position);0!==r;){for(;Q(r);)9===r&&-1===e.firstTabInLine&&(e.firstTabInLine=e.position),r=e.input.charCodeAt(++e.position);if(t&&35===r)do{r=e.input.charCodeAt(++e.position)}while(10!==r&&13!==r&&0!==r);if(!J(r))break;for(he(e),r=e.input.charCodeAt(e.position),i++,e.lineIndent=0;32===r;)e.lineIndent++,r=e.input.charCodeAt(++e.position)}return-1!==n&&0!==i&&e.lineIndent<n&&se(e,"deficient indentation"),i}function me(e){var t,n=e.position;return!(45!==(t=e.input.charCodeAt(n))&&46!==t||t!==e.input.charCodeAt(n+1)||t!==e.input.charCodeAt(n+2)||(n+=3,0!==(t=e.input.charCodeAt(n))&&!z(t)))}function ye(e,t){1===t?e.result+=" ":t>1&&(e.result+=n.repeat("\n",t-1))}function be(e,t){var n,i,r=e.tag,o=e.anchor,a=[],l=!1;if(-1!==e.firstTabInLine)return!1;for(null!==e.anchor&&(e.anchorMap[e.anchor]=a),i=e.input.charCodeAt(e.position);0!==i&&(-1!==e.firstTabInLine&&(e.position=e.firstTabInLine,ce(e,"tab characters must not be used in indentation")),45===i)&&z(e.input.charCodeAt(e.position+1));)if(l=!0,e.position++,ge(e,!0,-1)&&e.lineIndent<=t)a.push(null),i=e.input.charCodeAt(e.position);else if(n=e.line,we(e,t,3,!1,!0),a.push(e.result),ge(e,!0,-1),i=e.input.charCodeAt(e.position),(e.line===n||e.lineIndent>t)&&0!==i)ce(e,"bad indentation of a sequence entry");else if(e.lineIndent<t)break;return!!l&&(e.tag=r,e.anchor=o,e.kind="sequence",e.result=a,!0)}function Ae(e){var t,n,i,r,o=!1,a=!1;if(33!==(r=e.input.charCodeAt(e.position)))return!1;if(null!==e.tag&&ce(e,"duplication of a tag property"),60===(r=e.input.charCodeAt(++e.position))?(o=!0,r=e.input.charCodeAt(++e.position)):33===r?(a=!0,n="!!",r=e.input.charCodeAt(++e.position)):n="!",t=e.position,o){do{r=e.input.charCodeAt(++e.position)}while(0!==r&&62!==r);e.position<e.length?(i=e.input.slice(t,e.position),r=e.input.charCodeAt(++e.position)):ce(e,"unexpected end of the stream within a verbatim tag")}else{for(;0!==r&&!z(r);)33===r&&(a?ce(e,"tag suffix cannot contain exclamation marks"):(n=e.input.slice(t-1,e.position+1),G.test(n)||ce(e,"named tag handle cannot contain such characters"),a=!0,t=e.position+1)),r=e.input.charCodeAt(++e.position);i=e.input.slice(t,e.position),$.test(i)&&ce(e,"tag suffix cannot contain flow indicator characters")}i&&!V.test(i)&&ce(e,"tag name cannot contain such characters: "+i);try{i=decodeURIComponent(i)}catch(t){ce(e,"tag name is malformed: "+i)}return o?e.tag=i:P.call(e.tagMap,n)?e.tag=e.tagMap[n]+i:"!"===n?e.tag="!"+i:"!!"===n?e.tag="tag:yaml.org,2002:"+i:ce(e,'undeclared tag handle "'+n+'"'),!0}function ve(e){var t,n;if(38!==(n=e.input.charCodeAt(e.position)))return!1;for(null!==e.anchor&&ce(e,"duplication of an anchor property"),n=e.input.charCodeAt(++e.position),t=e.position;0!==n&&!z(n)&&!X(n);)n=e.input.charCodeAt(++e.position);return e.position===t&&ce(e,"name of an anchor node must contain at least one character"),e.anchor=e.input.slice(t,e.position),!0}function we(e,t,i,r,o){var a,l,c,s,u,p,f,d,h,g=1,m=!1,y=!1;if(null!==e.listener&&e.listener("open",e),e.tag=null,e.anchor=null,e.kind=null,e.result=null,a=l=c=4===i||3===i,r&&ge(e,!0,-1)&&(m=!0,e.lineIndent>t?g=1:e.lineIndent===t?g=0:e.lineIndent<t&&(g=-1)),1===g)for(;Ae(e)||ve(e);)ge(e,!0,-1)?(m=!0,c=a,e.lineIndent>t?g=1:e.lineIndent===t?g=0:e.lineIndent<t&&(g=-1)):c=!1;if(c&&(c=m||o),1!==g&&4!==i||(d=1===i||2===i?t:t+1,h=e.position-e.lineStart,1===g?c&&(be(e,h)||function(e,t,n){var i,r,o,a,l,c,s,u=e.tag,p=e.anchor,f={},d=Object.create(null),h=null,g=null,m=null,y=!1,b=!1;if(-1!==e.firstTabInLine)return!1;for(null!==e.anchor&&(e.anchorMap[e.anchor]=f),s=e.input.charCodeAt(e.position);0!==s;){if(y||-1===e.firstTabInLine||(e.position=e.firstTabInLine,ce(e,"tab characters must not be used in indentation")),i=e.input.charCodeAt(e.position+1),o=e.line,63!==s&&58!==s||!z(i)){if(a=e.line,l=e.lineStart,c=e.position,!we(e,n,2,!1,!0))break;if(e.line===o){for(s=e.input.charCodeAt(e.position);Q(s);)s=e.input.charCodeAt(++e.position);if(58===s)z(s=e.input.charCodeAt(++e.position))||ce(e,"a whitespace character is expected after the key-value separator within a block mapping"),y&&(de(e,f,d,h,g,null,a,l,c),h=g=m=null),b=!0,y=!1,r=!1,h=e.tag,g=e.result;else{if(!b)return e.tag=u,e.anchor=p,!0;ce(e,"can not read an implicit mapping pair; a colon is missed")}}else{if(!b)return e.tag=u,e.anchor=p,!0;ce(e,"can not read a block mapping entry; a multiline key may not be an implicit key")}}else 63===s?(y&&(de(e,f,d,h,g,null,a,l,c),h=g=m=null),b=!0,y=!0,r=!0):y?(y=!1,r=!0):ce(e,"incomplete explicit mapping pair; a key node is missed; or followed by a non-tabulated empty line"),e.position+=1,s=i;if((e.line===o||e.lineIndent>t)&&(y&&(a=e.line,l=e.lineStart,c=e.position),we(e,t,4,!0,r)&&(y?g=e.result:m=e.result),y||(de(e,f,d,h,g,m,a,l,c),h=g=m=null),ge(e,!0,-1),s=e.input.charCodeAt(e.position)),(e.line===o||e.lineIndent>t)&&0!==s)ce(e,"bad indentation of a mapping entry");else if(e.lineIndent<t)break}return y&&de(e,f,d,h,g,null,a,l,c),b&&(e.tag=u,e.anchor=p,e.kind="mapping",e.result=f),b}(e,h,d))||function(e,t){var n,i,r,o,a,l,c,s,u,p,f,d,h=!0,g=e.tag,m=e.anchor,y=Object.create(null);if(91===(d=e.input.charCodeAt(e.position)))a=93,s=!1,o=[];else{if(123!==d)return!1;a=125,s=!0,o={}}for(null!==e.anchor&&(e.anchorMap[e.anchor]=o),d=e.input.charCodeAt(++e.position);0!==d;){if(ge(e,!0,t),(d=e.input.charCodeAt(e.position))===a)return e.position++,e.tag=g,e.anchor=m,e.kind=s?"mapping":"sequence",e.result=o,!0;h?44===d&&ce(e,"expected the node content, but found ','"):ce(e,"missed comma between flow collection entries"),f=null,l=c=!1,63===d&&z(e.input.charCodeAt(e.position+1))&&(l=c=!0,e.position++,ge(e,!0,t)),n=e.line,i=e.lineStart,r=e.position,we(e,t,1,!1,!0),p=e.tag,u=e.result,ge(e,!0,t),d=e.input.charCodeAt(e.position),!c&&e.line!==n||58!==d||(l=!0,d=e.input.charCodeAt(++e.position),ge(e,!0,t),we(e,t,1,!1,!0),f=e.result),s?de(e,o,y,p,u,f,n,i,r):l?o.push(de(e,null,y,p,u,f,n,i,r)):o.push(u),ge(e,!0,t),44===(d=e.input.charCodeAt(e.position))?(h=!0,d=e.input.charCodeAt(++e.position)):h=!1}ce(e,"unexpected end of the stream within a flow collection")}(e,d)?y=!0:(l&&function(e,t){var i,r,o,a,l,c=1,s=!1,u=!1,p=t,f=0,d=!1;if(124===(a=e.input.charCodeAt(e.position)))r=!1;else{if(62!==a)return!1;r=!0}for(e.kind="scalar",e.result="";0!==a;)if(43===(a=e.input.charCodeAt(++e.position))||45===a)1===c?c=43===a?3:2:ce(e,"repeat of a chomping mode identifier");else{if(!((o=48<=(l=a)&&l<=57?l-48:-1)>=0))break;0===o?ce(e,"bad explicit indentation width of a block scalar; it cannot be less than one"):u?ce(e,"repeat of an indentation width identifier"):(p=t+o-1,u=!0)}if(Q(a)){do{a=e.input.charCodeAt(++e.position)}while(Q(a));if(35===a)do{a=e.input.charCodeAt(++e.position)}while(!J(a)&&0!==a)}for(;0!==a;){for(he(e),e.lineIndent=0,a=e.input.charCodeAt(e.position);(!u||e.lineIndent<p)&&32===a;)e.lineIndent++,a=e.input.charCodeAt(++e.position);if(!u&&e.lineIndent>p&&(p=e.lineIndent),J(a))f++;else{if(e.lineIndent<p){3===c?e.result+=n.repeat("\n",s?1+f:f):1===c&&s&&(e.result+="\n");break}for(r?Q(a)?(d=!0,e.result+=n.repeat("\n",s?1+f:f)):d?(d=!1,e.result+=n.repeat("\n",f+1)):0===f?s&&(e.result+=" "):e.result+=n.repeat("\n",f):e.result+=n.repeat("\n",s?1+f:f),s=!0,u=!0,f=0,i=e.position;!J(a)&&0!==a;)a=e.input.charCodeAt(++e.position);pe(e,i,e.position,!1)}}return!0}(e,d)||function(e,t){var n,i,r;if(39!==(n=e.input.charCodeAt(e.position)))return!1;for(e.kind="scalar",e.result="",e.position++,i=r=e.position;0!==(n=e.input.charCodeAt(e.position));)if(39===n){if(pe(e,i,e.position,!0),39!==(n=e.input.charCodeAt(++e.position)))return!0;i=e.position,e.position++,r=e.position}else J(n)?(pe(e,i,r,!0),ye(e,ge(e,!1,t)),i=r=e.position):e.position===e.lineStart&&me(e)?ce(e,"unexpected end of the document within a single quoted scalar"):(e.position++,r=e.position);ce(e,"unexpected end of the stream within a single quoted scalar")}(e,d)||function(e,t){var n,i,r,o,a,l,c;if(34!==(l=e.input.charCodeAt(e.position)))return!1;for(e.kind="scalar",e.result="",e.position++,n=i=e.position;0!==(l=e.input.charCodeAt(e.position));){if(34===l)return pe(e,n,e.position,!0),e.position++,!0;if(92===l){if(pe(e,n,e.position,!0),J(l=e.input.charCodeAt(++e.position)))ge(e,!1,t);else if(l<256&&ie[l])e.result+=re[l],e.position++;else if((a=120===(c=l)?2:117===c?4:85===c?8:0)>0){for(r=a,o=0;r>0;r--)(a=ee(l=e.input.charCodeAt(++e.position)))>=0?o=(o<<4)+a:ce(e,"expected hexadecimal character");e.result+=ne(o),e.position++}else ce(e,"unknown escape sequence");n=i=e.position}else J(l)?(pe(e,n,i,!0),ye(e,ge(e,!1,t)),n=i=e.position):e.position===e.lineStart&&me(e)?ce(e,"unexpected end of the document within a double quoted scalar"):(e.position++,i=e.position)}ce(e,"unexpected end of the stream within a double quoted scalar")}(e,d)?y=!0:!function(e){var t,n,i;if(42!==(i=e.input.charCodeAt(e.position)))return!1;for(i=e.input.charCodeAt(++e.position),t=e.position;0!==i&&!z(i)&&!X(i);)i=e.input.charCodeAt(++e.position);return e.position===t&&ce(e,"name of an alias node must contain at least one character"),n=e.input.slice(t,e.position),P.call(e.anchorMap,n)||ce(e,'unidentified alias "'+n+'"'),e.result=e.anchorMap[n],ge(e,!0,-1),!0}(e)?function(e,t,n){var i,r,o,a,l,c,s,u,p=e.kind,f=e.result;if(z(u=e.input.charCodeAt(e.position))||X(u)||35===u||38===u||42===u||33===u||124===u||62===u||39===u||34===u||37===u||64===u||96===u)return!1;if((63===u||45===u)&&(z(i=e.input.charCodeAt(e.position+1))||n&&X(i)))return!1;for(e.kind="scalar",e.result="",r=o=e.position,a=!1;0!==u;){if(58===u){if(z(i=e.input.charCodeAt(e.position+1))||n&&X(i))break}else if(35===u){if(z(e.input.charCodeAt(e.position-1)))break}else{if(e.position===e.lineStart&&me(e)||n&&X(u))break;if(J(u)){if(l=e.line,c=e.lineStart,s=e.lineIndent,ge(e,!1,-1),e.lineIndent>=t){a=!0,u=e.input.charCodeAt(e.position);continue}e.position=o,e.line=l,e.lineStart=c,e.lineIndent=s;break}}a&&(pe(e,r,o,!1),ye(e,e.line-l),r=o=e.position,a=!1),Q(u)||(o=e.position+1),u=e.input.charCodeAt(++e.position)}return pe(e,r,o,!1),!!e.result||(e.kind=p,e.result=f,!1)}(e,d,1===i)&&(y=!0,null===e.tag&&(e.tag="?")):(y=!0,null===e.tag&&null===e.anchor||ce(e,"alias node should not have any properties")),null!==e.anchor&&(e.anchorMap[e.anchor]=e.result)):0===g&&(y=c&&be(e,h))),null===e.tag)null!==e.anchor&&(e.anchorMap[e.anchor]=e.result);else if("?"===e.tag){for(null!==e.result&&"scalar"!==e.kind&&ce(e,'unacceptable node kind for !<?> tag; it should be "scalar", not "'+e.kind+'"'),s=0,u=e.implicitTypes.length;s<u;s+=1)if((f=e.implicitTypes[s]).resolve(e.result)){e.result=f.construct(e.result),e.tag=f.tag,null!==e.anchor&&(e.anchorMap[e.anchor]=e.result);break}}else if("!"!==e.tag){if(P.call(e.typeMap[e.kind||"fallback"],e.tag))f=e.typeMap[e.kind||"fallback"][e.tag];else for(f=null,s=0,u=(p=e.typeMap.multi[e.kind||"fallback"]).length;s<u;s+=1)if(e.tag.slice(0,p[s].tag.length)===p[s].tag){f=p[s];break}f||ce(e,"unknown tag !<"+e.tag+">"),null!==e.result&&f.kind!==e.kind&&ce(e,"unacceptable node kind for !<"+e.tag+'> tag; it should be "'+f.kind+'", not "'+e.kind+'"'),f.resolve(e.result,e.tag)?(e.result=f.construct(e.result,e.tag),null!==e.anchor&&(e.anchorMap[e.anchor]=e.result)):ce(e,"cannot resolve a node with !<"+e.tag+"> explicit tag")}return null!==e.listener&&e.listener("close",e),null!==e.tag||null!==e.anchor||y}function ke(e){var t,n,i,r,o=e.position,a=!1;for(e.version=null,e.checkLineBreaks=e.legacy,e.tagMap=Object.create(null),e.anchorMap=Object.create(null);0!==(r=e.input.charCodeAt(e.position))&&(ge(e,!0,-1),r=e.input.charCodeAt(e.position),!(e.lineIndent>0||37!==r));){for(a=!0,r=e.input.charCodeAt(++e.position),t=e.position;0!==r&&!z(r);)r=e.input.charCodeAt(++e.position);for(i=[],(n=e.input.slice(t,e.position)).length<1&&ce(e,"directive name must not be less than one character in length");0!==r;){for(;Q(r);)r=e.input.charCodeAt(++e.position);if(35===r){do{r=e.input.charCodeAt(++e.position)}while(0!==r&&!J(r));break}if(J(r))break;for(t=e.position;0!==r&&!z(r);)r=e.input.charCodeAt(++e.position);i.push(e.input.slice(t,e.position))}0!==r&&he(e),P.call(ue,n)?ue[n](e,n,i):se(e,'unknown document directive "'+n+'"')}ge(e,!0,-1),0===e.lineIndent&&45===e.input.charCodeAt(e.position)&&45===e.input.charCodeAt(e.position+1)&&45===e.input.charCodeAt(e.position+2)?(e.position+=3,ge(e,!0,-1)):a&&ce(e,"directives end mark is expected"),we(e,e.lineIndent-1,4,!1,!0),ge(e,!0,-1),e.checkLineBreaks&&H.test(e.input.slice(o,e.position))&&se(e,"non-ASCII line breaks are interpreted as content"),e.documents.push(e.result),e.position===e.lineStart&&me(e)?46===e.input.charCodeAt(e.position)&&(e.position+=3,ge(e,!0,-1)):e.position<e.length-1&&ce(e,"end of the stream or a document separator is expected")}function Ce(e,t){t=t||{},0!==(e=String(e)).length&&(10!==e.charCodeAt(e.length-1)&&13!==e.charCodeAt(e.length-1)&&(e+="\n"),65279===e.charCodeAt(0)&&(e=e.slice(1)));var n=new ae(e,t),i=e.indexOf("\0");for(-1!==i&&(n.position=i,ce(n,"null byte is not allowed in input")),n.input+="\0";32===n.input.charCodeAt(n.position);)n.lineIndent+=1,n.position+=1;for(;n.position<n.length-1;)ke(n);return n.documents}var xe={loadAll:function(e,t,n){null!==t&&"object"==typeof t&&void 0===n&&(n=t,t=null);var i=Ce(e,n);if("function"!=typeof t)return i;for(var r=0,o=i.length;r<o;r+=1)t(i[r])},load:function(e,t){var n=Ce(e,t);if(0!==n.length){if(1===n.length)return n[0];throw new o("expected a single document in the stream, but found more")}}},Ie=Object.prototype.toString,Se=Object.prototype.hasOwnProperty,Oe=65279,je={0:"\\0",7:"\\a",8:"\\b",9:"\\t",10:"\\n",11:"\\v",12:"\\f",13:"\\r",27:"\\e",34:'\\"',92:"\\\\",133:"\\N",160:"\\_",8232:"\\L",8233:"\\P"},Te=["y","Y","yes","Yes","YES","on","On","ON","n","N","no","No","NO","off","Off","OFF"],Ne=/^[-+]?[0-9_]+(?::[0-9_]+)+(?:\.[0-9_]*)?$/;function Fe(e){var t,i,r;if(t=e.toString(16).toUpperCase(),e<=255)i="x",r=2;else if(e<=65535)i="u",r=4;else{if(!(e<=4294967295))throw new o("code point within a string may not be greater than 0xFFFFFFFF");i="U",r=8}return"\\"+i+n.repeat("0",r-t.length)+t}function Ee(e){this.schema=e.schema||K,this.indent=Math.max(1,e.indent||2),this.noArrayIndent=e.noArrayIndent||!1,this.skipInvalid=e.skipInvalid||!1,this.flowLevel=n.isNothing(e.flowLevel)?-1:e.flowLevel,this.styleMap=function(e,t){var n,i,r,o,a,l,c;if(null===t)return{};for(n={},r=0,o=(i=Object.keys(t)).length;r<o;r+=1)a=i[r],l=String(t[a]),"!!"===a.slice(0,2)&&(a="tag:yaml.org,2002:"+a.slice(2)),(c=e.compiledTypeMap.fallback[a])&&Se.call(c.styleAliases,l)&&(l=c.styleAliases[l]),n[a]=l;return n}(this.schema,e.styles||null),this.sortKeys=e.sortKeys||!1,this.lineWidth=e.lineWidth||80,this.noRefs=e.noRefs||!1,this.noCompatMode=e.noCompatMode||!1,this.condenseFlow=e.condenseFlow||!1,this.quotingType='"'===e.quotingType?2:1,this.forceQuotes=e.forceQuotes||!1,this.replacer="function"==typeof e.replacer?e.replacer:null,this.implicitTypes=this.schema.compiledImplicit,this.explicitTypes=this.schema.compiledExplicit,this.tag=null,this.result="",this.duplicates=[],this.usedDuplicates=null}function Me(e,t){for(var i,r=n.repeat(" ",t),o=0,a=-1,l="",c=e.length;o<c;)-1===(a=e.indexOf("\n",o))?(i=e.slice(o),o=c):(i=e.slice(o,a+1),o=a+1),i.length&&"\n"!==i&&(l+=r),l+=i;return l}function Le(e,t){return"\n"+n.repeat(" ",e.indent*t)}function _e(e){return 32===e||9===e}function De(e){return 32<=e&&e<=126||161<=e&&e<=55295&&8232!==e&&8233!==e||57344<=e&&e<=65533&&e!==Oe||65536<=e&&e<=1114111}function Ue(e){return De(e)&&e!==Oe&&13!==e&&10!==e}function qe(e,t,n){var i=Ue(e),r=i&&!_e(e);return(n?i:i&&44!==e&&91!==e&&93!==e&&123!==e&&125!==e)&&35!==e&&!(58===t&&!r)||Ue(t)&&!_e(t)&&35===e||58===t&&r}function Ye(e,t){var n,i=e.charCodeAt(t);return i>=55296&&i<=56319&&t+1<e.length&&(n=e.charCodeAt(t+1))>=56320&&n<=57343?1024*(i-55296)+n-56320+65536:i}function Re(e){return/^\n* /.test(e)}function Be(e,t,n,i,r,o,a,l){var c,s,u=0,p=null,f=!1,d=!1,h=-1!==i,g=-1,m=De(s=Ye(e,0))&&s!==Oe&&!_e(s)&&45!==s&&63!==s&&58!==s&&44!==s&&91!==s&&93!==s&&123!==s&&125!==s&&35!==s&&38!==s&&42!==s&&33!==s&&124!==s&&61!==s&&62!==s&&39!==s&&34!==s&&37!==s&&64!==s&&96!==s&&function(e){return!_e(e)&&58!==e}(Ye(e,e.length-1));if(t||a)for(c=0;c<e.length;u>=65536?c+=2:c++){if(!De(u=Ye(e,c)))return 5;m=m&&qe(u,p,l),p=u}else{for(c=0;c<e.length;u>=65536?c+=2:c++){if(10===(u=Ye(e,c)))f=!0,h&&(d=d||c-g-1>i&&" "!==e[g+1],g=c);else if(!De(u))return 5;m=m&&qe(u,p,l),p=u}d=d||h&&c-g-1>i&&" "!==e[g+1]}return f||d?n>9&&Re(e)?5:a?2===o?5:2:d?4:3:!m||a||r(e)?2===o?5:2:1}function Ke(e,t,n,i,r){e.dump=function(){if(0===t.length)return 2===e.quotingType?'""':"''";if(!e.noCompatMode&&(-1!==Te.indexOf(t)||Ne.test(t)))return 2===e.quotingType?'"'+t+'"':"'"+t+"'";var a=e.indent*Math.max(1,n),l=-1===e.lineWidth?-1:Math.max(Math.min(e.lineWidth,40),e.lineWidth-a),c=i||e.flowLevel>-1&&n>=e.flowLevel;switch(Be(t,c,e.indent,l,(function(t){return function(e,t){var n,i;for(n=0,i=e.implicitTypes.length;n<i;n+=1)if(e.implicitTypes[n].resolve(t))return!0;return!1}(e,t)}),e.quotingType,e.forceQuotes&&!i,r)){case 1:return t;case 2:return"'"+t.replace(/'/g,"''")+"'";case 3:return"|"+Pe(t,e.indent)+We(Me(t,a));case 4:return">"+Pe(t,e.indent)+We(Me(function(e,t){var n,i,r=/(\n+)([^\n]*)/g,o=(l=e.indexOf("\n"),l=-1!==l?l:e.length,r.lastIndex=l,He(e.slice(0,l),t)),a="\n"===e[0]||" "===e[0];var l;for(;i=r.exec(e);){var c=i[1],s=i[2];n=" "===s[0],o+=c+(a||n||""===s?"":"\n")+He(s,t),a=n}return o}(t,l),a));case 5:return'"'+function(e){for(var t,n="",i=0,r=0;r<e.length;i>=65536?r+=2:r++)i=Ye(e,r),!(t=je[i])&&De(i)?(n+=e[r],i>=65536&&(n+=e[r+1])):n+=t||Fe(i);return n}(t)+'"';default:throw new o("impossible error: invalid scalar style")}}()}function Pe(e,t){var n=Re(e)?String(t):"",i="\n"===e[e.length-1];return n+(i&&("\n"===e[e.length-2]||"\n"===e)?"+":i?"":"-")+"\n"}function We(e){return"\n"===e[e.length-1]?e.slice(0,-1):e}function He(e,t){if(""===e||" "===e[0])return e;for(var n,i,r=/ [^ ]/g,o=0,a=0,l=0,c="";n=r.exec(e);)(l=n.index)-o>t&&(i=a>o?a:l,c+="\n"+e.slice(o,i),o=i+1),a=l;return c+="\n",e.length-o>t&&a>o?c+=e.slice(o,a)+"\n"+e.slice(a+1):c+=e.slice(o),c.slice(1)}function $e(e,t,n,i){var r,o,a,l="",c=e.tag;for(r=0,o=n.length;r<o;r+=1)a=n[r],e.replacer&&(a=e.replacer.call(n,String(r),a)),(Ve(e,t+1,a,!0,!0,!1,!0)||void 0===a&&Ve(e,t+1,null,!0,!0,!1,!0))&&(i&&""===l||(l+=Le(e,t)),e.dump&&10===e.dump.charCodeAt(0)?l+="-":l+="- ",l+=e.dump);e.tag=c,e.dump=l||"[]"}function Ge(e,t,n){var i,r,a,l,c,s;for(a=0,l=(r=n?e.explicitTypes:e.implicitTypes).length;a<l;a+=1)if(((c=r[a]).instanceOf||c.predicate)&&(!c.instanceOf||"object"==typeof t&&t instanceof c.instanceOf)&&(!c.predicate||c.predicate(t))){if(n?c.multi&&c.representName?e.tag=c.representName(t):e.tag=c.tag:e.tag="?",c.represent){if(s=e.styleMap[c.tag]||c.defaultStyle,"[object Function]"===Ie.call(c.represent))i=c.represent(t,s);else{if(!Se.call(c.represent,s))throw new o("!<"+c.tag+'> tag resolver accepts not "'+s+'" style');i=c.represent[s](t,s)}e.dump=i}return!0}return!1}function Ve(e,t,n,i,r,a,l){e.tag=null,e.dump=n,Ge(e,n,!1)||Ge(e,n,!0);var c,s=Ie.call(e.dump),u=i;i&&(i=e.flowLevel<0||e.flowLevel>t);var p,f,d="[object Object]"===s||"[object Array]"===s;if(d&&(f=-1!==(p=e.duplicates.indexOf(n))),(null!==e.tag&&"?"!==e.tag||f||2!==e.indent&&t>0)&&(r=!1),f&&e.usedDuplicates[p])e.dump="*ref_"+p;else{if(d&&f&&!e.usedDuplicates[p]&&(e.usedDuplicates[p]=!0),"[object Object]"===s)i&&0!==Object.keys(e.dump).length?(!function(e,t,n,i){var r,a,l,c,s,u,p="",f=e.tag,d=Object.keys(n);if(!0===e.sortKeys)d.sort();else if("function"==typeof e.sortKeys)d.sort(e.sortKeys);else if(e.sortKeys)throw new o("sortKeys must be a boolean or a function");for(r=0,a=d.length;r<a;r+=1)u="",i&&""===p||(u+=Le(e,t)),c=n[l=d[r]],e.replacer&&(c=e.replacer.call(n,l,c)),Ve(e,t+1,l,!0,!0,!0)&&((s=null!==e.tag&&"?"!==e.tag||e.dump&&e.dump.length>1024)&&(e.dump&&10===e.dump.charCodeAt(0)?u+="?":u+="? "),u+=e.dump,s&&(u+=Le(e,t)),Ve(e,t+1,c,!0,s)&&(e.dump&&10===e.dump.charCodeAt(0)?u+=":":u+=": ",p+=u+=e.dump));e.tag=f,e.dump=p||"{}"}(e,t,e.dump,r),f&&(e.dump="&ref_"+p+e.dump)):(!function(e,t,n){var i,r,o,a,l,c="",s=e.tag,u=Object.keys(n);for(i=0,r=u.length;i<r;i+=1)l="",""!==c&&(l+=", "),e.condenseFlow&&(l+='"'),a=n[o=u[i]],e.replacer&&(a=e.replacer.call(n,o,a)),Ve(e,t,o,!1,!1)&&(e.dump.length>1024&&(l+="? "),l+=e.dump+(e.condenseFlow?'"':"")+":"+(e.condenseFlow?"":" "),Ve(e,t,a,!1,!1)&&(c+=l+=e.dump));e.tag=s,e.dump="{"+c+"}"}(e,t,e.dump),f&&(e.dump="&ref_"+p+" "+e.dump));else if("[object Array]"===s)i&&0!==e.dump.length?(e.noArrayIndent&&!l&&t>0?$e(e,t-1,e.dump,r):$e(e,t,e.dump,r),f&&(e.dump="&ref_"+p+e.dump)):(!function(e,t,n){var i,r,o,a="",l=e.tag;for(i=0,r=n.length;i<r;i+=1)o=n[i],e.replacer&&(o=e.replacer.call(n,String(i),o)),(Ve(e,t,o,!1,!1)||void 0===o&&Ve(e,t,null,!1,!1))&&(""!==a&&(a+=","+(e.condenseFlow?"":" ")),a+=e.dump);e.tag=l,e.dump="["+a+"]"}(e,t,e.dump),f&&(e.dump="&ref_"+p+" "+e.dump));else{if("[object String]"!==s){if("[object Undefined]"===s)return!1;if(e.skipInvalid)return!1;throw new o("unacceptable kind of an object to dump "+s)}"?"!==e.tag&&Ke(e,e.dump,t,a,u)}null!==e.tag&&"?"!==e.tag&&(c=encodeURI("!"===e.tag[0]?e.tag.slice(1):e.tag).replace(/!/g,"%21"),c="!"===e.tag[0]?"!"+c:"tag:yaml.org,2002:"===c.slice(0,18)?"!!"+c.slice(18):"!<"+c+">",e.dump=c+" "+e.dump)}return!0}function Ze(e,t){var n,i,r=[],o=[];for(Je(e,r,o),n=0,i=o.length;n<i;n+=1)t.duplicates.push(r[o[n]]);t.usedDuplicates=new Array(i)}function Je(e,t,n){var i,r,o;if(null!==e&&"object"==typeof e)if(-1!==(r=t.indexOf(e)))-1===n.indexOf(r)&&n.push(r);else if(t.push(e),Array.isArray(e))for(r=0,o=e.length;r<o;r+=1)Je(e[r],t,n);else for(r=0,o=(i=Object.keys(e)).length;r<o;r+=1)Je(e[i[r]],t,n)}function Qe(e,t){return function(){throw new Error("Function yaml."+e+" is removed in js-yaml 4. Use yaml."+t+" instead, which is now safe by default.")}}var ze=p,Xe=h,et=b,tt=O,nt=j,it=K,rt=xe.load,ot=xe.loadAll,at={dump:function(e,t){var n=new Ee(t=t||{});n.noRefs||Ze(e,n);var i=e;return n.replacer&&(i=n.replacer.call({"":i},"",i)),Ve(n,0,i,!0,!0)?n.dump+"\n":""}}.dump,lt=o,ct={binary:L,float:S,map:y,null:A,pairs:Y,set:B,timestamp:F,bool:v,int:C,merge:E,omap:U,seq:m,str:g},st=Qe("safeLoad","load"),ut=Qe("safeLoadAll","loadAll"),pt=Qe("safeDump","dump"),ft={Type:ze,Schema:Xe,FAILSAFE_SCHEMA:et,JSON_SCHEMA:tt,CORE_SCHEMA:nt,DEFAULT_SCHEMA:it,load:rt,loadAll:ot,dump:at,YAMLException:lt,types:ct,safeLoad:st,safeLoadAll:ut,safeDump:pt};e.CORE_SCHEMA=nt,e.DEFAULT_SCHEMA=it,e.FAILSAFE_SCHEMA=et,e.JSON_SCHEMA=tt,e.Schema=Xe,e.Type=ze,e.YAMLException=lt,e.default=ft,e.dump=at,e.load=rt,e.loadAll=ot,e.safeDump=pt,e.safeLoad=st,e.safeLoadAll=ut,e.types=ct,Object.defineProperty(e,"__esModule",{value:!0})}));
diff --git a/overrides/assets/stylesheets/specifications.css b/overrides/assets/stylesheets/specifications.css
index 54aa65a..fc87ee8 100644
--- a/overrides/assets/stylesheets/specifications.css
+++ b/overrides/assets/stylesheets/specifications.css
@@ -1673,6 +1673,269 @@ buttons
 :is(.mdip-specs, .mdip-spec) li.spec-row { display: block; }
 :is(.mdip-specs, .mdip-spec) li.spec-row[hidden] { display: none; }
 
+/* -- adoption: known adopters over time ------------------------------------ */
+
+/* One series, so no legend: the heading names it. Time runs across, the count
+   runs up from zero, and only the latest value is written out. The plot is a
+   stretched SVG for the line, with the dots and labels laid over it in HTML so
+   they keep their shape at any width. */
+:is(.mdip-specs, .mdip-spec) .adopt-hist { margin-top: 1.1rem; }
+:is(.mdip-specs, .mdip-spec) .adopt-hist h3,
+:is(.mdip-specs, .mdip-spec) .hist__group {
+  display: flex;
+  align-items: center;
+  gap: .4em;
+  margin: 0 0 .5rem;
+  color: var(--ink-3);
+  font-size: .6rem;
+  font-weight: 700;
+  letter-spacing: .07em;
+  text-transform: uppercase;
+}
+
+/* Material centres a figure and shrinks it to its content (`width:
+   fit-content`, a flex column); the chart is a block as wide as the section. */
+:is(.mdip-specs, .mdip-spec) figure.adopt-chart {
+  display: block;
+  width: auto;
+  max-width: none;
+  margin: 0;
+  padding: 1.1rem 1rem .6rem 3.1rem;
+  border: 1px solid var(--line);
+  border-radius: var(--r-m);
+  background: var(--surface);
+  box-shadow: var(--sh-1);
+}
+
+:is(.mdip-specs, .mdip-spec) .adopt-chart__plot { position: relative; height: 8.5rem; }
+
+:is(.mdip-specs, .mdip-spec) .adopt-chart__plot svg {
+  position: absolute;
+  inset: 0;
+  width: 100%;
+  height: 100%;
+  overflow: visible;
+}
+:is(.mdip-specs, .mdip-spec) .adopt-chart__grid { stroke: var(--line); stroke-width: 1; stroke-dasharray: 3 3; }
+:is(.mdip-specs, .mdip-spec) .adopt-chart__base { stroke: var(--line-strong); stroke-width: 1; }
+:is(.mdip-specs, .mdip-spec) .adopt-chart__area { fill: var(--brand); opacity: .08; }
+:is(.mdip-specs, .mdip-spec) .adopt-chart__line {
+  fill: none;
+  stroke: var(--brand);
+  stroke-width: 2;
+  stroke-linejoin: round;
+  stroke-linecap: round;
+}
+
+:is(.mdip-specs, .mdip-spec) .adopt-chart__y {
+  position: absolute;
+  right: calc(100% + .55rem);
+  transform: translateY(-50%);
+  color: var(--ink-3);
+  font-size: .58rem;
+  font-variant-numeric: tabular-nums;
+  line-height: 1;
+  white-space: nowrap;
+}
+
+:is(.mdip-specs, .mdip-spec) .adopt-chart__dot {
+  position: absolute;
+  width: 8px;
+  height: 8px;
+  border-radius: 50%;
+  background: var(--brand);
+  box-shadow: 0 0 0 2px var(--surface);
+  transform: translate(-50%, -50%);
+  outline: none;
+}
+/* A larger, invisible hit area than the dot itself. */
+:is(.mdip-specs, .mdip-spec) .adopt-chart__dot::before { content: ""; position: absolute; inset: -9px; border-radius: 50%; }
+:is(.mdip-specs, .mdip-spec) .adopt-chart__dot:focus-visible { box-shadow: 0 0 0 2px var(--surface), 0 0 0 4px var(--brand); }
+
+:is(.mdip-specs, .mdip-spec) .adopt-chart__tip {
+  position: absolute;
+  bottom: calc(100% + .45rem);
+  left: 50%;
+  z-index: 2;
+  padding: .2rem .45rem;
+  border-radius: 6px;
+  background: var(--ink);
+  color: var(--bg);
+  font-size: .6rem;
+  font-weight: 600;
+  white-space: nowrap;
+  transform: translateX(-50%);
+  opacity: 0;
+  pointer-events: none;
+  transition: opacity .15s var(--ease);
+}
+:is(.mdip-specs, .mdip-spec) .adopt-chart__dot.is-last .adopt-chart__tip { left: auto; right: -.3rem; transform: none; }
+:is(.mdip-specs, .mdip-spec) .adopt-chart__dot:is(:hover, :focus) .adopt-chart__tip { opacity: 1; }
+
+:is(.mdip-specs, .mdip-spec) .adopt-chart__val {
+  position: absolute;
+  transform: translate(-100%, -170%);
+  color: var(--ink);
+  font-size: .7rem;
+  font-weight: 700;
+  font-variant-numeric: tabular-nums;
+  line-height: 1;
+  white-space: nowrap;
+  pointer-events: none;
+}
+
+:is(.mdip-specs, .mdip-spec) .adopt-chart__x {
+  display: flex;
+  justify-content: space-between;
+  margin-top: .45rem;
+  color: var(--ink-3);
+  font-size: .58rem;
+}
+
+/* The slate scheme sets its attribute on <body>, an ancestor of the roots. */
+[data-md-color-scheme="slate"] .mdip-spec .adopt-chart__line { stroke: var(--info); }
+[data-md-color-scheme="slate"] .mdip-spec .adopt-chart__area { fill: var(--info); }
+[data-md-color-scheme="slate"] .mdip-spec .adopt-chart__dot { background: var(--info); }
+[data-md-color-scheme="slate"] .mdip-spec .adopt-chart__dot:focus-visible { box-shadow: 0 0 0 2px var(--surface), 0 0 0 4px var(--info); }
+
+/* -- history --------------------------------------------------------------- */
+
+/* Each change is one row of a single card: what state it is in, what it is
+   called, who proposed and merged it, and the start of its description. The
+   field-by-field table is open for proposals, which are what a reader comes
+   to check, and folded for merged changes, whose result is already the page. */
+:is(.mdip-specs, .mdip-spec) .hist__group { margin-top: 1rem; }
+:is(.mdip-specs, .mdip-spec) .hist__group:first-child { margin-top: 0; }
+
+/* Element and class together: Material's `[dir=ltr] .md-typeset ol li`
+   indents and numbers list items at 0-2-2. */
+:is(.mdip-specs, .mdip-spec) ol.hist__list {
+  margin: 0;
+  padding: 0;
+  list-style: none;
+  border: 1px solid var(--line);
+  border-radius: var(--r-m);
+  background: var(--surface);
+  box-shadow: var(--sh-1);
+  overflow: hidden;
+}
+
+:is(.mdip-specs, .mdip-spec) ol.hist__list > li.hist__item { margin: 0; padding: .7rem .9rem .75rem; }
+:is(.mdip-specs, .mdip-spec) ol.hist__list > li.hist__item + li.hist__item { border-top: 1px solid var(--line); }
+
+:is(.mdip-specs, .mdip-spec) .hist__top {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: .5rem;
+  margin-bottom: .35rem;
+}
+:is(.mdip-specs, .mdip-spec) .hist__date {
+  color: var(--ink-3);
+  font-size: .62rem;
+  font-variant-numeric: tabular-nums;
+  white-space: nowrap;
+}
+
+:is(.mdip-specs, .mdip-spec) .hist__title {
+  display: inline;
+  color: var(--ink) !important;
+  font-family: "Raleway", system-ui, sans-serif;
+  font-size: .78rem;
+  font-weight: 700;
+  line-height: 1.35;
+  text-decoration: none;
+}
+:is(.mdip-specs, .mdip-spec) .hist__title:hover span:first-child { color: var(--brand); text-decoration: underline; }
+:is(.mdip-specs, .mdip-spec) .hist__num {
+  margin-left: .35em;
+  color: var(--ink-3);
+  font-family: "Poppins", system-ui, sans-serif;
+  font-size: .66rem;
+  font-weight: 500;
+}
+
+:is(.mdip-specs, .mdip-spec) .hist__by {
+  display: flex;
+  flex-wrap: wrap;
+  gap: .1rem .9rem;
+  margin: .25rem 0 0;
+  color: var(--ink-3);
+  font-size: .64rem;
+}
+:is(.mdip-specs, .mdip-spec) .hist__by a { font-weight: 600; }
+
+:is(.mdip-specs, .mdip-spec) .hist__desc {
+  margin: .35rem 0 0;
+  color: var(--ink-2);
+  font-size: .66rem;
+  line-height: 1.55;
+}
+
+:is(.mdip-specs, .mdip-spec) .hist__scroll {
+  margin-top: .55rem;
+  border: 1px solid var(--line);
+  border-radius: var(--r-s);
+  overflow-x: auto;
+}
+:is(.mdip-specs, .mdip-spec) .hist__t {
+  display: table;
+  width: 100%;
+  margin: 0;
+  border-collapse: collapse;
+  font-size: .64rem;
+  line-height: 1.45;
+}
+:is(.mdip-specs, .mdip-spec) .hist__t :is(th, td) {
+  padding: .35rem .6rem;
+  border: 0;
+  border-top: 1px solid var(--line);
+  text-align: left;
+  vertical-align: top;
+  overflow-wrap: anywhere;
+}
+:is(.mdip-specs, .mdip-spec) .hist__t thead th {
+  border-top: 0;
+  background: var(--surface-2);
+  color: var(--ink-3);
+  font-size: .58rem;
+  font-weight: 700;
+  letter-spacing: .05em;
+  text-transform: uppercase;
+}
+:is(.mdip-specs, .mdip-spec) .hist__t tbody th { width: 34%; color: var(--ink-2); font-weight: 600; }
+:is(.mdip-specs, .mdip-spec) .hist__old { color: var(--ink-3); }
+:is(.mdip-specs, .mdip-spec) .hist__new { color: var(--ink); font-weight: 600; }
+:is(.mdip-specs, .mdip-spec) .hist__t .is-empty { font-style: italic; font-weight: 400; color: var(--ink-3); }
+
+:is(.mdip-specs, .mdip-spec) details.hist__more { margin-top: .4rem; }
+:is(.mdip-specs, .mdip-spec) details.hist__more > summary {
+  display: inline-flex;
+  gap: .45em;
+  padding: 0;
+  color: var(--ink-3);
+  font-size: .62rem;
+  cursor: pointer;
+}
+:is(.mdip-specs, .mdip-spec) details.hist__more > summary:hover { color: var(--ink); }
+:is(.mdip-specs, .mdip-spec) details.hist__more > summary::-webkit-details-marker { display: none; }
+:is(.mdip-specs, .mdip-spec) .hist__n { color: var(--ink-3); font-weight: 400; }
+:is(.mdip-specs, .mdip-spec) .hist__n::before { content: "\00b7"; margin-right: .45em; }
+
+:is(.mdip-specs, .mdip-spec) .hist__extra { margin: .35rem 0 0; font-size: .62rem; }
+
+:is(.mdip-specs, .mdip-spec) .hist__note {
+  display: flex;
+  align-items: center;
+  flex-wrap: wrap;
+  gap: .35em;
+  margin: .35rem 0 0;
+  color: var(--ink-3);
+  font-size: .66rem;
+}
+:is(.mdip-specs, .mdip-spec) .hist__body > .hist__note:first-child { margin-top: 0; }
+:is(.mdip-specs, .mdip-spec) .hist__foot { margin: .8rem 0 0; }
+
 /* --------------------------------------------------------------------------
    Material <details> overrides
 
@@ -1686,7 +1949,8 @@ buttons
 :is(.mdip-specs, .mdip-spec) details.facet,
 :is(.mdip-specs, .mdip-spec) details.disclosure,
 :is(.mdip-specs, .mdip-spec) details.crit,
-:is(.mdip-specs, .mdip-spec) details.specs-defer {
+:is(.mdip-specs, .mdip-spec) details.specs-defer,
+:is(.mdip-specs, .mdip-spec) details.hist__more {
   display: block;
   overflow: visible;
   padding: 0;
@@ -1718,7 +1982,8 @@ buttons
 :is(.mdip-specs, .mdip-spec) details.facet > summary,
 :is(.mdip-specs, .mdip-spec) details.disclosure > summary,
 :is(.mdip-specs, .mdip-spec) details.crit > summary,
-:is(.mdip-specs, .mdip-spec) details.specs-defer > summary {
+:is(.mdip-specs, .mdip-spec) details.specs-defer > summary,
+:is(.mdip-specs, .mdip-spec) details.hist__more > summary {
   display: flex;
   align-items: center;
   /* Material bleeds the admonition title past its box with `margin: 0 -.6rem`,
@@ -1756,7 +2021,9 @@ buttons
 :is(.mdip-specs, .mdip-spec) details.crit > summary::before,
 :is(.mdip-specs, .mdip-spec) details.crit > summary::after,
 :is(.mdip-specs, .mdip-spec) details.specs-defer > summary::before,
-:is(.mdip-specs, .mdip-spec) details.specs-defer > summary::after {
+:is(.mdip-specs, .mdip-spec) details.specs-defer > summary::after,
+:is(.mdip-specs, .mdip-spec) details.hist__more > summary::before,
+:is(.mdip-specs, .mdip-spec) details.hist__more > summary::after {
   display: none;
   content: none;
 }
@@ -1770,6 +2037,8 @@ buttons
   padding: .55rem .75rem;
 }
 :is(.mdip-specs, .mdip-spec) details.specs-defer > summary { gap: .45em; padding: .5em .7em; font-size: .68rem; }
+:is(.mdip-specs, .mdip-spec) details.hist__more { border: 0; margin-top: .4rem; }
+:is(.mdip-specs, .mdip-spec) details.hist__more > summary { display: inline-flex; padding: 0; color: var(--ink-3); font-size: .62rem; }
 
 /* --------------------------------------------------------------------------
    Motion preference
diff --git a/scripts/spec_data.py b/scripts/spec_data.py
index 6fc388c..1032a1e 100644
--- a/scripts/spec_data.py
+++ b/scripts/spec_data.py
@@ -102,6 +102,9 @@
     ("microtransit_drt", "Microtransit/DRT"),
     ("taxi_ridehail", "Taxi/Ridehail"),
     ("bicycle", "Bicycle"),
+    ("bikeshare", "Bikeshare"),
+    ("shared_scooter", "Shared scooter"),
+    ("carsharing", "Carsharing"),
     ("pedestrian_accessibility", "Pedestrian/Accessibility"),
     ("parking", "Parking"),
 ])
@@ -183,7 +186,12 @@ def read_entry(path):
     `# Description` and any section added later are read the same way.
     """
     with open(path, encoding="utf-8") as fh:
-        text = fh.read().replace("\r\n", "\n")
+        return parse_entry(fh.read())
+
+
+def parse_entry(text):
+    """`read_entry` on text already in memory, such as a past git revision."""
+    text = text.replace("\r\n", "\n")
     if not text.startswith("---\n"):
         raise ValueError("does not start with a --- front matter block")
     end = text.find("\n---\n", 4)
diff --git a/scripts/spec_history.py b/scripts/spec_history.py
new file mode 100644
index 0000000..848e120
--- /dev/null
+++ b/scripts/spec_history.py
@@ -0,0 +1,119 @@
+"""Past values of the registry, read from the repository's git history.
+
+Every change to a file in data/ is a commit, so the history of a value needs
+no extra bookkeeping: each revision of a specification file is read back and
+parsed like the current one. Only the known adopters count is tracked today,
+for the chart in the Adoption section of each specification page.
+
+Everything here is best effort. Without git, outside a clone, or in a shallow
+clone the history is simply shorter or empty, and the page leaves the chart
+out rather than failing the build.
+"""
+
+from __future__ import annotations
+
+import subprocess
+
+import spec_data
+
+_CACHE = {}
+
+
+def _git(args, stdin=None):
+    return subprocess.run(["git", "-C", spec_data.ROOT] + args, input=stdin,
+                          capture_output=True, check=True).stdout
+
+
+def _revisions():
+    """{repository path: [(commit, commit date), ...]}, oldest first."""
+    log = _git(["log", "--reverse", "--format=%x00%H %cs", "--name-only", "--",
+                "data/" + spec_data.SPECS_DIR]).decode("utf-8")
+    out = {}
+    for block in log.split("\0")[1:]:
+        lines = [l for l in block.splitlines() if l.strip()]
+        sha, date = lines[0].split()
+        for path in lines[1:]:
+            out.setdefault(path, []).append((sha, date))
+    return out
+
+
+def _blobs(refs):
+    """Contents of many `<commit>:<path>` at once, None where a path is gone."""
+    if not refs:
+        return {}
+    raw = _git(["cat-file", "--batch"], ("\n".join(refs) + "\n").encode("utf-8"))
+    out, pos = {}, 0
+    for ref in refs:
+        end = raw.index(b"\n", pos)
+        header = raw[pos:end].decode("utf-8")
+        pos = end + 1
+        if header.endswith(" missing"):
+            out[ref] = None
+            continue
+        size = int(header.rsplit(" ", 1)[1])
+        out[ref] = raw[pos:pos + size].decode("utf-8", "replace")
+        pos += size + 1
+    return out
+
+
+def _adopters(text):
+    try:
+        front, _sections = spec_data.parse_entry(text)
+    except Exception:       # a broken revision is skipped, not fatal
+        return None, None
+    adoption = front.get("adoption") if isinstance(front, dict) else None
+    if not isinstance(adoption, dict):
+        return None, None
+    count = adoption.get("adopters_count")
+    if not isinstance(count, int) or isinstance(count, bool) or count < 0:
+        return None, None
+    return count, spec_data.as_text(adoption.get("adopters_count_updated")) or None
+
+
+def _committed_counts():
+    """{path: [(count, count date or None, commit date), ...]} from git.
+
+    A revision that leaves the count and its date as they were (any other edit
+    to the file) is not a new count, so it is skipped.
+    """
+    try:
+        head = _git(["rev-parse", "HEAD"]).decode().strip()
+    except (OSError, subprocess.CalledProcessError):
+        return {}
+    if head not in _CACHE:
+        try:
+            revisions = _revisions()
+            refs = ["%s:%s" % (sha, path) for path, revs in revisions.items()
+                    for sha, _date in revs]
+            blobs = _blobs(refs)
+        except (OSError, subprocess.CalledProcessError, ValueError):
+            revisions, blobs = {}, {}
+        counts = {}
+        for path, revs in revisions.items():
+            for sha, date in revs:
+                text = blobs.get("%s:%s" % (sha, path))
+                count, updated = _adopters(text) if text else (None, None)
+                seen = counts.setdefault(path, [])
+                if count is not None and (not seen or seen[-1][:2] != (count, updated)):
+                    seen.append((count, updated, date))
+        _CACHE.clear()
+        _CACHE[head] = counts
+    return _CACHE[head]
+
+
+def adopters_series(spec, today=None):
+    """Known adopters over time for one specification, oldest first.
+
+    One point per date: the date the count was taken (`adopters_count_updated`)
+    when the file gives one, otherwise the date of the commit that recorded
+    it. The file as it is now is the last point, so a local edit shows up in a
+    preview before it is committed. A later value for the same date replaces
+    the earlier one, because that is a correction rather than a new count.
+    """
+    committed = _committed_counts().get(spec["source_path"], [])
+    points = dict((updated or date, count) for count, updated, date in committed)
+    current = (spec["adopters_count"], spec["adopters_count_updated"])
+    if current[0] is not None and (not committed or committed[-1][:2] != current):
+        import datetime
+        points[current[1] or today or datetime.date.today().isoformat()] = current[0]
+    return [{"date": d, "count": points[d]} for d in sorted(points)]