diff --git a/frontend_tests/zjsunit/bugdown_assert.js b/frontend_tests/zjsunit/bugdown_assert.js
index c303049d55..46bfd8989a 100644
--- a/frontend_tests/zjsunit/bugdown_assert.js
+++ b/frontend_tests/zjsunit/bugdown_assert.js
@@ -58,10 +58,8 @@ class MarkdownComparer {
         if (node1.content.childNodes.length !== node2.content.childNodes.length) {
             return false;
         }
-        return _.reduce(
-            _.zip(node1.content.childNodes, node2.content.childNodes),
-            (prev, nodePair) => { return prev && nodePair[0].isEqualNode(nodePair[1]); },
-            true
+        return _.zip(node1.content.childNodes, node2.content.childNodes).every(([child1, child2]) =>
+            child1.isEqualNode(child2)
         );
     }
 
diff --git a/static/js/composebox_typeahead.js b/static/js/composebox_typeahead.js
index 55d7210c9a..805b9ceb36 100644
--- a/static/js/composebox_typeahead.js
+++ b/static/js/composebox_typeahead.js
@@ -366,12 +366,7 @@ function should_show_custom_query(query, items) {
     if (!query) {
         return false;
     }
-    const matched = _.reduce(items, function (matched, elem) {
-        if (elem.toLowerCase() === query.toLowerCase()) {
-            return true;
-        }
-        return matched;
-    }, false);
+    const matched = items.some(elem => elem.toLowerCase() === query.toLowerCase());
     return !matched;
 }
 
diff --git a/static/js/list_render.js b/static/js/list_render.js
index 0b6c9649b6..8ca0c9002c 100644
--- a/static/js/list_render.js
+++ b/static/js/list_render.js
@@ -93,7 +93,8 @@ exports.create = function ($container, list, opts) {
             const slice = meta.filtered_list.slice(meta.offset, meta.offset + load_count);
 
             const finish = blueslip.start_timing('list_render ' + opts.name);
-            const html = _.reduce(slice, function (acc, item) {
+            let html = "";
+            for (const item of slice) {
                 let _item = opts.modifier(item);
 
                 // if valid jQuery selection, attempt to grab all elements within
@@ -116,9 +117,9 @@ exports.create = function ($container, list, opts) {
                     _item = _item.outerHTML;
                 }
 
-                // return the modified HTML or nothing if corrupt (null, undef, etc.).
-                return acc + (_item || "");
-            }, "");
+                // append the HTML or nothing if corrupt (null, undef, etc.).
+                html += _item || "";
+            }
 
             finish();