diff --git a/apps/web/src/pierre-icons.test.ts b/apps/web/src/pierre-icons.test.ts
index 0ffceec70136c..734cac8655379 100644
--- a/apps/web/src/pierre-icons.test.ts
+++ b/apps/web/src/pierre-icons.test.ts
@@ -3,6 +3,7 @@ import { assert, describe, it } from "vite-plus/test";
 import {
   hasSpecificPierreIconForFileName,
   resolvePierreIconForEntry,
+  syntheticFileNameForLanguageId,
   T3_PIERRE_ICONS,
 } from "./pierre-icons";
 
@@ -64,4 +65,22 @@ describe("Pierre file icons", () => {
       assert.include(T3_PIERRE_ICONS.spriteSheet, `id="${iconName}"`);
     }
   });
+
+  it.each([
+    ["luau", "lua"],
+    ["xsd", "xml"],
+    ["xsl", "xml"],
+    ["xslt", "xml"],
+  ])("gives %s files and fences the %s icon", (dialect, base) => {
+    const baseIcon = resolvePierreIconForEntry(`file.${base}`, "file")?.name;
+    assert.equal(baseIcon, `t3-file-icon-${base}`);
+    for (const path of [`src/init.${dialect}`, `src/INIT.${dialect.toUpperCase()}`]) {
+      assert.equal(resolvePierreIconForEntry(path, "file")?.name, baseIcon);
+      assert.isTrue(hasSpecificPierreIconForFileName(path));
+    }
+    assert.equal(
+      resolvePierreIconForEntry(syntheticFileNameForLanguageId(dialect), "file")?.name,
+      baseIcon,
+    );
+  });
 });
diff --git a/apps/web/src/pierre-icons.ts b/apps/web/src/pierre-icons.ts
index 852ccc26e127e..aa45b3025c103 100644
--- a/apps/web/src/pierre-icons.ts
+++ b/apps/web/src/pierre-icons.ts
@@ -176,6 +176,7 @@ export const T3_PIERRE_ICONS = {
     kt: "t3-file-icon-kotlin",
     kts: "t3-file-icon-kotlin",
     lua: "t3-file-icon-lua",
+    luau: "t3-file-icon-lua",
     php: "t3-file-icon-php",
     ps1: "t3-file-icon-powershell",
     psm1: "t3-file-icon-powershell",
@@ -184,6 +185,9 @@ export const T3_PIERRE_ICONS = {
     scala: "t3-file-icon-scala",
     toml: "t3-file-icon-toml",
     xml: "t3-file-icon-xml",
+    xsd: "t3-file-icon-xml",
+    xsl: "t3-file-icon-xml",
+    xslt: "t3-file-icon-xml",
   },
 } satisfies FileTreeIcons;