diff --git a/common/components/primitives.py b/common/components/primitives.py
index ef1ec21..16a5dae 100644
--- a/common/components/primitives.py
+++ b/common/components/primitives.py
@@ -542,9 +542,15 @@ def StaticScript(filename: str) -> SafeText:
     return mark_safe(f'<script src="{static("js/" + filename)}"></script>')
 
 
-# Media for the Flowbite-datepicker year picker (vendored UMD bundle). Declared
-# on the YearPicker node so Page() loads it wherever a YearPicker appears.
-_YEAR_PICKER_MEDIA = Media(js_external=("datepicker.umd.js",))
+# Media for the Flowbite-datepicker year picker: the vendored UMD bundle
+# (classic script) plus the ts/year_picker.ts glue (compiled module). Declared
+# on the YearPicker node so Page() loads both wherever a YearPicker appears. The
+# UMD bundle is a classic script (runs during parse) while year_picker.js is a
+# deferred module (runs after parse), so Datepicker is defined by the time the
+# module executes regardless of tag order.
+_YEAR_PICKER_MEDIA = Media(
+    js_external=("datepicker.umd.js",), js=("dist/year_picker.js",)
+)
 
 
 def YearPicker(
@@ -589,44 +595,7 @@ def YearPicker(
            data-available-years="{years_csv}"
            data-selected-year="{selected}"
            data-url-template="{url_template}">
-</div>
-<script>
-document.addEventListener('DOMContentLoaded', () => {{
-    const pickerEl = document.getElementById('year-picker-input');
-    if (!pickerEl || pickerEl._pickerInstance) return;
-
-    const selectedYear = pickerEl.dataset.selectedYear;
-    const urlTemplate = pickerEl.dataset.urlTemplate;
-    const currentYear = new Date().getFullYear();
-    const availableYears = new Set(pickerEl.dataset.availableYears
-        .split(',').map(s => parseInt(s.trim())).filter(n => !isNaN(n)));
-
-    const picker = new Datepicker(pickerEl, {{
-        pickLevel: 2,
-        format: 'yyyy',
-        minDate: new Date(1999, 0, 1),
-        maxDate: new Date(currentYear, 11, 31),
-        autohide: false,
-        orientation: 'bottom end',
-        showOnClick: false,
-        showOnFocus: false,
-        beforeShowYear: (date) => ({{ enabled: availableYears.has(date.getFullYear()) }})
-    }});
-    pickerEl._pickerInstance = picker;
-
-    picker.element.addEventListener('changeDate', (e) => {{
-        const year = e.detail.date?.getFullYear();
-        if (year && urlTemplate) {{
-            window.location.href = urlTemplate.replace('__year__', year);
-        }}
-    }});
-
-    if (selectedYear) {{
-        picker.dates = [new Date(parseInt(selectedYear), 0, 1)];
-        picker.update();
-    }}
-}});
-</script>""",
+</div>""",
         media=_YEAR_PICKER_MEDIA,
     )
 
diff --git a/games/static/js/year_picker.js b/games/static/js/year_picker.js
deleted file mode 100644
index 7eeb843..0000000
--- a/games/static/js/year_picker.js
+++ /dev/null
@@ -1,38 +0,0 @@
-import { onSwap } from "./utils.js";
-
-onSwap("#year-picker-input", function(pickerEl) {
-    const selectedYear = pickerEl.dataset.selectedYear;
-    const urlTemplate = pickerEl.dataset.urlTemplate;
-    const currentYear = new Date().getFullYear();
-    const availableYears = new Set(
-        pickerEl.dataset.availableYears
-            .split(",")
-            .map(s => parseInt(s.trim()))
-            .filter(n => !isNaN(n))
-    );
-
-    const picker = new Datepicker(pickerEl, {
-        pickLevel: 2,
-        format: "yyyy",
-        minDate: new Date(1999, 0, 1),
-        maxDate: new Date(currentYear, 11, 31),
-        autohide: false,
-        orientation: "bottom end",
-        showOnClick: false,
-        showOnFocus: false,
-        beforeShowYear: (date) => ({ enabled: availableYears.has(date.getFullYear()) }),
-    });
-    pickerEl._pickerInstance = picker;
-
-    picker.element.addEventListener("changeDate", (event) => {
-        const year = event.detail.date?.getFullYear();
-        if (year && urlTemplate) {
-            window.location.href = urlTemplate.replace("__year__", year);
-        }
-    });
-
-    if (selectedYear) {
-        picker.dates = [new Date(parseInt(selectedYear), 0, 1)];
-        picker.update();
-    }
-});
diff --git a/ts/year_picker.ts b/ts/year_picker.ts
new file mode 100644
index 0000000..a11d3aa
--- /dev/null
+++ b/ts/year_picker.ts
@@ -0,0 +1,54 @@
+/**
+ * YearPicker — wires the Flowbite-datepicker year grid behind the YearPicker
+ * component (common/components/primitives.py). The component renders a hidden
+ * #year-picker-input carrying data-available-years / data-selected-year /
+ * data-url-template; this turns it into a year-level Datepicker and navigates
+ * to the chosen year's URL. Datepicker comes from the vendored UMD bundle
+ * (datepicker.umd.js), loaded as a classic script before this module runs.
+ */
+import { onSwap } from "./utils.js";
+
+declare const Datepicker: any;
+
+// The Alpine toggle button reaches the Datepicker instance through this prop.
+interface PickerElement extends HTMLInputElement {
+  _pickerInstance?: any;
+}
+
+onSwap("#year-picker-input", (element) => {
+  const pickerElement = element as PickerElement;
+  const selectedYear = pickerElement.dataset.selectedYear;
+  const urlTemplate = pickerElement.dataset.urlTemplate;
+  const currentYear = new Date().getFullYear();
+  const availableYears = new Set(
+    (pickerElement.dataset.availableYears ?? "")
+      .split(",")
+      .map((part) => parseInt(part.trim(), 10))
+      .filter((year) => !isNaN(year))
+  );
+
+  const picker = new Datepicker(pickerElement, {
+    pickLevel: 2,
+    format: "yyyy",
+    minDate: new Date(1999, 0, 1),
+    maxDate: new Date(currentYear, 11, 31),
+    autohide: false,
+    orientation: "bottom end",
+    showOnClick: false,
+    showOnFocus: false,
+    beforeShowYear: (date: Date) => ({ enabled: availableYears.has(date.getFullYear()) }),
+  });
+  pickerElement._pickerInstance = picker;
+
+  picker.element.addEventListener("changeDate", (event: Event) => {
+    const year = (event as CustomEvent).detail.date?.getFullYear();
+    if (year && urlTemplate) {
+      window.location.href = urlTemplate.replace("__year__", String(year));
+    }
+  });
+
+  if (selectedYear) {
+    picker.dates = [new Date(parseInt(selectedYear, 10), 0, 1)];
+    picker.update();
+  }
+});