diff --git a/backend/app/controllers/wiki_pages_controller.rb b/backend/app/controllers/wiki_pages_controller.rb
index 47a388a..c792fb7 100644
--- a/backend/app/controllers/wiki_pages_controller.rb
+++ b/backend/app/controllers/wiki_pages_controller.rb
@@ -66,14 +66,14 @@ class WikiPagesController < ApplicationController
   end
 
   def search
-    q = WikiPage.all
+    title = params[:title]&.strip
 
-    if params[:title].present?
-      title = params[:title].to_s.strip
-      q = q.where('title LIKE ?', "%#{ WikiPage.sanitize_sql_like(title) }%")
-    end
+    q = WikiPage.all
+    q = q.where('title LIKE ?', "%#{ WikiPage.sanitize_sql_like(title) }%") if title.present?
 
-    render json: q.limit(20)
+    render json: q.limit(20).map { |page|
+        page.sha = nil
+        page }
   end
 
   def changes
diff --git a/frontend/src/components/TopNav.tsx b/frontend/src/components/TopNav.tsx
index 1598e0f..3da0091 100644
--- a/frontend/src/components/TopNav.tsx
+++ b/frontend/src/components/TopNav.tsx
@@ -12,7 +12,7 @@ type Props = { user:    User
 
 const enum Menu { None,
                   Post,
-                  Deerjikist,
+                  User,
                   Tag,
                   Wiki }
 
@@ -28,6 +28,8 @@ const TopNav: React.FC = ({ user, setUser }: Props) => {
   const [activeIndex, setActiveIndex] = useState (-1)
   const [suggestions, setSuggestions] = useState<WikiPage[]> ([])
   const [suggestionsVsbl, setSuggestionsVsbl] = useState (false)
+  const [tagSearch, setTagSearch] = useState ('')
+  const [userSearch, setUserSearch] = useState ('')
 
   const MyLink = ({ to, title, menu, base }: { to:    string
                                                title: string
@@ -40,16 +42,43 @@ const TopNav: React.FC = ({ user, setUser }: Props) => {
         {title}
       </Link>)
 
-  const whenWikiSearchChanged = e => {
-    setWikiSearch (e.target.value)
+  const whenTagSearchChanged = ev => {
+    // TODO: 実装
 
-    const q: string = e.target.value.split (' ').at (-1)
+    setTagSearch (ev.target.value)
+
+    const q: string = ev.target.value.split (' ').at (-1)
+    if (!(q))
+      {
+        setSuggestions ([])
+        return
+      }
+  }
+
+  const whenWikiSearchChanged = ev => {
+    // TODO: 実装
+
+    setWikiSearch (ev.target.value)
+
+    const q: string = ev.target.value.split (' ').at (-1)
+    if (!(q))
+      {
+        setSuggestions ([])
+        return
+      }
+  }
+
+  const whenUserSearchChanged = ev => {
+    // TODO: 実装
+
+    setUserSearch (ev.target.value)
+
+    const q: string = ev.target.value.split (' ').at (-1)
     if (!(q))
       {
         setSuggestions ([])
         return
       }
-    // void (axios.get(`${ API_BASE_URL }/`))
   }
 
   const handleKeyDown = (e: React.KeyboardEvent<HTMLInputElement>) => {
@@ -70,8 +99,8 @@ const TopNav: React.FC = ({ user, setUser }: Props) => {
   useEffect (() => {
     if (location.pathname.startsWith ('/posts'))
       setSelectedMenu (Menu.Post)
-    else if (location.pathname.startsWith ('/deerjikists'))
-      setSelectedMenu (Menu.Deerjikist)
+    else if (location.pathname.startsWith ('/users'))
+      setSelectedMenu (Menu.User)
     else if (location.pathname.startsWith ('/tags'))
       setSelectedMenu (Menu.Tag)
     else if (location.pathname.startsWith ('/wiki'))
@@ -86,9 +115,9 @@ const TopNav: React.FC = ({ user, setUser }: Props) => {
           <div className="flex items-center gap-2 h-full">
             <Link to="/posts" className="mx-4 text-xl font-bold text-orange-500">ぼざクリ タグ広場</Link>
             <MyLink to="/posts" title="広場" />
-            <MyLink to="/deerjikists" title="ニジラー" />
             <MyLink to="/tags" title="タグ" />
             <MyLink to="/wiki/ヘルプ:ホーム" base="/wiki" title="Wiki" />
+            <MyLink to="/users" title="ニジラー" />
           </div>
           <div className="ml-auto pr-4">
             <Button onClick={() => setSettingsVsbl (true)}>{user?.name || '名もなきニジラー'}</Button>
@@ -112,6 +141,23 @@ const TopNav: React.FC = ({ user, setUser }: Props) => {
                   <Link to="/posts/new" className={subClass}>投稿追加</Link>
                   <Link to="/wiki/ヘルプ:広場" className={subClass}>ヘルプ</Link>
                 </div>)
+          case Menu.Tag:
+            return (
+                <div className={className}>
+                  <input type="text"
+                         className={inputBox}
+                         placeholder="タグ検索"
+                         value={tagSearch}
+                         onChange={whenTagSearchChanged}
+                         onFocus={() => setSuggestionsVsbl (true)}
+                         onBlur={() => setSuggestionsVsbl (false)}
+                         onKeyDown={handleKeyDown} />
+                  <Link to="/tags" className={subClass}>タグ</Link>
+                  <Link to="/tags/aliases" className={subClass}>別名タグ</Link>
+                  <Link to="/tags/implications" className={subClass}>上位タグ</Link>
+                  <Link to="/wiki/ヘルプ:タグのつけ方" className={subClass}>タグのつけ方</Link>
+                  <Link to="/wiki/ヘルプ:タグ" className={subClass}>ヘルプ</Link>
+                </div>)
           case Menu.Wiki:
             return (
                 <div className={className}>
@@ -135,6 +181,20 @@ const TopNav: React.FC = ({ user, setUser }: Props) => {
                         <Link to={`/wiki/${ wikiId || location.pathname.split ('/')[2] }/edit`} className={subClass}>編輯</Link>
                       </>}
                 </div>)
+          case Menu.User:
+            return (
+                <div className={className}>
+                  <input type="text"
+                         className={inputBox}
+                         placeholder="ニジラー検索"
+                         value={userSearch}
+                         onChange={whenUserSearchChanged}
+                         onFocus={() => setSuggestionsVsbl (true)}
+                         onBlur={() => setSuggestionsVsbl (false)}
+                         onKeyDown={handleKeyDown} />
+                  <Link to="/users" className={subClass}>一覧</Link>
+                  {user && <Link to={`/users/${ user.id }`} className={subClass}>お前</Link>}
+                </div>)
           }
         }) ()}
       </>)
diff --git a/frontend/src/pages/posts/PostListPage.tsx b/frontend/src/pages/posts/PostListPage.tsx
index 5344d13..2d12448 100644
--- a/frontend/src/pages/posts/PostListPage.tsx
+++ b/frontend/src/pages/posts/PostListPage.tsx
@@ -14,7 +14,7 @@ import type { Post, Tag, WikiPage } from '@/types'
 
 
 export default () => {
-  const [posts, setPosts] = useState<Post[]> ([])
+  const [posts, setPosts] = useState<Post[] | null> (null)
   const [wikiPage, setWikiPage] = useState<WikiPage | null> (null)
 
   const location = useLocation ()
@@ -30,7 +30,7 @@ export default () => {
           .then (res => setPosts (toCamel (res.data, { deep: true })))
           .catch (err => {
             console.error ('Failed to fetch posts:', err)
-            setPosts ([])
+            setPosts (null)
           }))
 
     setWikiPage (null)
@@ -53,25 +53,26 @@ export default () => {
              : `${ SITE_TITLE }　〜 ぼざクリも、ぼざろ外も、外伝もあるんだよ`}
           </title>
         </Helmet>
-        <TagSidebar posts={posts} />
+        <TagSidebar posts={posts || []} />
         <MainArea>
           <TabGroup key={wikiPage}>
             <Tab name="広場">
-              {posts.length
-               ? (
-                  <div className="flex flex-wrap gap-4 p-4">
-                    {posts.map (post => (
-                        <Link to={`/posts/${ post.id }`}
-                              key={post.id}
-                              className="w-40 h-40 overflow-hidden rounded-lg shadow-md hover:shadow-lg">
-                          <img src={post.thumbnail ?? post.thumbnailBase}
-                               className="object-none w-full h-full" />
-                        </Link>))}
-                  </div>)
-               : '広場には何もありませんよ．'}
+              {posts == null ? 'Loading...' : (
+                  posts.length
+                  ? (
+                     <div className="flex flex-wrap gap-4 p-4">
+                       {posts.map (post => (
+                           <Link to={`/posts/${ post.id }`}
+                                 key={post.id}
+                                 className="w-40 h-40 overflow-hidden rounded-lg shadow-md hover:shadow-lg">
+                             <img src={post.thumbnail ?? post.thumbnailBase}
+                                  className="object-none w-full h-full" />
+                           </Link>))}
+                     </div>)
+                  : '広場には何もありませんよ．')}
             </Tab>
             {(wikiPage && wikiPage.body) && (
-                <Tab name="Wiki" init={!(posts.length)}>
+                <Tab name="Wiki" init={!(posts?.length)}>
                   <WikiBody body={wikiPage.body} />
                   <div className="my-2">
                     <Link to={`/wiki/${ wikiPage.title }`}>Wiki を見る</Link>
diff --git a/frontend/src/pages/wiki/WikiSearchPage.tsx b/frontend/src/pages/wiki/WikiSearchPage.tsx
index 855fb4a..41243d7 100644
--- a/frontend/src/pages/wiki/WikiSearchPage.tsx
+++ b/frontend/src/pages/wiki/WikiSearchPage.tsx
@@ -1,4 +1,5 @@
 import axios from 'axios'
+import toCamel from 'camelcase-keys'
 import React, { useEffect, useState } from 'react'
 import { Helmet } from 'react-helmet'
 import { Link } from 'react-router-dom'
@@ -17,7 +18,7 @@ export default () => {
 
   const search = () => {
     void (axios.get (`${ API_BASE_URL }/wiki/search`, { params: { title } })
-          .then (res => setResults (res.data)))
+          .then (res => setResults (toCamel (res.data, { deep: true }))))
   }
 
   const handleSearch = (e: React.FormEvent) => {
@@ -82,7 +83,7 @@ export default () => {
                       </Link>
                     </td>
                     <td className="p-2 text-gray-100 text-sm">
-                      {page.updated_at}
+                      {page.updatedAt}
                     </td>
                   </tr>))}
             </tbody>