diff --git a/judge/caching.py b/judge/caching.py
index b8fb810..8f42d24 100644
--- a/judge/caching.py
+++ b/judge/caching.py
@@ -1,27 +1,32 @@
 from inspect import signature
-from django.core.cache import cache
+from django.core.cache import cache, caches
 from django.db.models.query import QuerySet
 from django.core.handlers.wsgi import WSGIRequest
 
 import hashlib
 
-MAX_NUM_CHAR = 15
+MAX_NUM_CHAR = 50
 NONE_RESULT = "__None__"
 
 
+def arg_to_str(arg):
+    if hasattr(arg, "id"):
+        return str(arg.id)
+    if isinstance(arg, list) or isinstance(arg, QuerySet):
+        return hashlib.sha1(str(list(arg)).encode()).hexdigest()[:MAX_NUM_CHAR]
+    if len(str(arg)) > MAX_NUM_CHAR:
+        return str(arg)[:MAX_NUM_CHAR]
+    return str(arg)
+
+
+def filter_args(args_list):
+    return [x for x in args_list if not isinstance(x, WSGIRequest)]
+
+
+l0_cache = caches["l0"] if "l0" in caches else None
+
+
 def cache_wrapper(prefix, timeout=None):
-    def arg_to_str(arg):
-        if hasattr(arg, "id"):
-            return str(arg.id)
-        if isinstance(arg, list) or isinstance(arg, QuerySet):
-            return hashlib.sha1(str(list(arg)).encode()).hexdigest()[:MAX_NUM_CHAR]
-        if len(str(arg)) > MAX_NUM_CHAR:
-            return str(arg)[:MAX_NUM_CHAR]
-        return str(arg)
-
-    def filter_args(args_list):
-        return [x for x in args_list if not isinstance(x, WSGIRequest)]
-
     def get_key(func, *args, **kwargs):
         args_list = list(args)
         signature_args = list(signature(func).parameters.keys())
@@ -32,23 +37,41 @@ def cache_wrapper(prefix, timeout=None):
         key = key.replace(" ", "_")
         return key
 
+    def _get(key):
+        if not l0_cache:
+            return cache.get(key)
+        print("GET", key, l0_cache.get(key))
+        return l0_cache.get(key) or cache.get(key)
+
+    def _set_l0(key, value):
+        if l0_cache:
+            print("SET", key, value)
+            l0_cache.set(key, value, 30)
+
+    def _set(key, value, timeout):
+        _set_l0(key, value)
+        cache.set(key, value, timeout)
+
     def decorator(func):
         def wrapper(*args, **kwargs):
             cache_key = get_key(func, *args, **kwargs)
-            result = cache.get(cache_key)
+            result = _get(cache_key)
             if result is not None:
+                _set_l0(cache_key, result)
                 if result == NONE_RESULT:
                     result = None
                 return result
             result = func(*args, **kwargs)
             if result is None:
                 result = NONE_RESULT
-            cache.set(cache_key, result, timeout)
+            _set(cache_key, result, timeout)
             return result
 
         def dirty(*args, **kwargs):
             cache_key = get_key(func, *args, **kwargs)
             cache.delete(cache_key)
+            if l0_cache:
+                l0_cache.delete(cache_key)
 
         wrapper.dirty = dirty
 
diff --git a/judge/jinja2/__init__.py b/judge/jinja2/__init__.py
index 93d0ed5..93ab0ad 100644
--- a/judge/jinja2/__init__.py
+++ b/judge/jinja2/__init__.py
@@ -21,7 +21,6 @@ from . import (
     render,
     social,
     spaceless,
-    submission,
     timedelta,
 )
 from . import registry
diff --git a/judge/jinja2/submission.py b/judge/jinja2/submission.py
deleted file mode 100644
index cdb3634..0000000
--- a/judge/jinja2/submission.py
+++ /dev/null
@@ -1,41 +0,0 @@
-from . import registry
-
-
-@registry.function
-def submission_layout(
-    submission,
-    profile_id,
-    user,
-    editable_problem_ids,
-    completed_problem_ids,
-    tester_problem_ids,
-):
-    problem_id = submission.problem_id
-
-    if problem_id in editable_problem_ids:
-        return True
-
-    if problem_id in tester_problem_ids:
-        return True
-
-    if profile_id == submission.user_id:
-        return True
-
-    if user.has_perm("judge.change_submission"):
-        return True
-
-    if user.has_perm("judge.view_all_submission"):
-        return True
-
-    if submission.problem.is_public and user.has_perm("judge.view_public_submission"):
-        return True
-
-    if hasattr(submission, "contest"):
-        contest = submission.contest.participation.contest
-        if contest.is_editable_by(user):
-            return True
-
-    if submission.problem_id in completed_problem_ids and submission.problem.is_public:
-        return True
-
-    return False
diff --git a/judge/models/submission.py b/judge/models/submission.py
index fea9b64..842b627 100644
--- a/judge/models/submission.py
+++ b/judge/models/submission.py
@@ -220,6 +220,47 @@ class Submission(models.Model):
     def id_secret(self):
         return self.get_id_secret(self.id)
 
+    def is_accessible_by(self, profile):
+        from judge.utils.problems import (
+            user_completed_ids,
+            user_tester_ids,
+            user_editable_ids,
+        )
+
+        if not profile:
+            return False
+
+        problem_id = self.problem_id
+        user = profile.user
+
+        if profile.id == self.user_id:
+            return True
+
+        if problem_id in user_editable_ids(profile):
+            return True
+
+        if self.problem_id in user_completed_ids(profile):
+            if self.problem.is_public:
+                return True
+            if problem_id in user_tester_ids(profile):
+                return True
+
+        if user.has_perm("judge.change_submission"):
+            return True
+
+        if user.has_perm("judge.view_all_submission"):
+            return True
+
+        if self.problem.is_public and user.has_perm("judge.view_public_submission"):
+            return True
+
+        if hasattr(
+            self, "contest"
+        ) and self.contest.participation.contest.is_editable_by(user):
+            return True
+
+        return False
+
     class Meta:
         permissions = (
             ("abort_any_submission", "Abort any submission"),
diff --git a/judge/utils/problems.py b/judge/utils/problems.py
index 6c351aa..5861fa7 100644
--- a/judge/utils/problems.py
+++ b/judge/utils/problems.py
@@ -10,6 +10,8 @@ from django.db.models import Case, Count, ExpressionWrapper, F, Max, Q, When
 from django.db.models.fields import FloatField
 from django.utils import timezone
 from django.utils.translation import gettext as _, gettext_noop
+from django.db.models.signals import pre_save
+from django.dispatch import receiver
 
 from judge.models import Problem, Submission
 from judge.ml.collab_filter import CollabFilter
@@ -24,6 +26,7 @@ __all__ = [
 ]
 
 
+@cache_wrapper(prefix="user_tester")
 def user_tester_ids(profile):
     return set(
         Problem.testers.through.objects.filter(profile=profile).values_list(
@@ -32,6 +35,7 @@ def user_tester_ids(profile):
     )
 
 
+@cache_wrapper(prefix="user_editable")
 def user_editable_ids(profile):
     result = set(
         (
@@ -42,22 +46,19 @@ def user_editable_ids(profile):
     return result
 
 
+@cache_wrapper(prefix="contest_complete")
 def contest_completed_ids(participation):
-    key = "contest_complete:%d" % participation.id
-    result = cache.get(key)
-    if result is None:
-        result = set(
-            participation.submissions.filter(
-                submission__result="AC", points=F("problem__points")
-            )
-            .values_list("problem__problem__id", flat=True)
-            .distinct()
+    result = set(
+        participation.submissions.filter(
+            submission__result="AC", points=F("problem__points")
         )
-        cache.set(key, result, 86400)
+        .values_list("problem__problem__id", flat=True)
+        .distinct()
+    )
     return result
 
 
-@cache_wrapper(prefix="user_complete", timeout=86400)
+@cache_wrapper(prefix="user_complete")
 def user_completed_ids(profile):
     result = set(
         Submission.objects.filter(
@@ -69,7 +70,7 @@ def user_completed_ids(profile):
     return result
 
 
-@cache_wrapper(prefix="contest_attempted", timeout=86400)
+@cache_wrapper(prefix="contest_attempted")
 def contest_attempted_ids(participation):
     result = {
         id: {"achieved_points": points, "max_points": max_points}
@@ -84,7 +85,7 @@ def contest_attempted_ids(participation):
     return result
 
 
-@cache_wrapper(prefix="user_attempted", timeout=86400)
+@cache_wrapper(prefix="user_attempted")
 def user_attempted_ids(profile):
     result = {
         id: {
@@ -248,3 +249,22 @@ def finished_submission(sub):
         keys += ["contest_complete:%d" % participation.id]
         keys += ["contest_attempted:%d" % participation.id]
     cache.delete_many(keys)
+
+
+@receiver([pre_save], sender=Problem)
+def on_problem_save(sender, instance, **kwargs):
+    if instance.id is None:
+        return
+    prev_editors = list(sender.objects.get(id=instance.id).editor_ids)
+    new_editors = list(instance.editor_ids)
+    if prev_editors != new_editors:
+        all_editors = set(prev_editors + new_editors)
+        for profile_id in all_editors:
+            user_editable_ids.dirty(profile_id)
+
+    prev_testers = list(sender.objects.get(id=instance.id).tester_ids)
+    new_testers = list(instance.tester_ids)
+    if prev_testers != new_testers:
+        all_testers = set(prev_testers + new_testers)
+        for profile_id in all_testers:
+            user_tester_ids.dirty(profile_id)
diff --git a/judge/views/submission.py b/judge/views/submission.py
index 1556dd9..eae961b 100644
--- a/judge/views/submission.py
+++ b/judge/views/submission.py
@@ -84,31 +84,7 @@ class SubmissionMixin(object):
 class SubmissionDetailBase(LoginRequiredMixin, TitleMixin, SubmissionMixin, DetailView):
     def get_object(self, queryset=None):
         submission = super(SubmissionDetailBase, self).get_object(queryset)
-        profile = self.request.profile
-        problem = submission.problem
-        if self.request.user.has_perm("judge.view_all_submission"):
-            return submission
-        if problem.is_public and self.request.user.has_perm(
-            "judge.view_public_submission"
-        ):
-            return submission
-        if submission.user_id == profile.id:
-            return submission
-        if problem.is_editor(profile):
-            return submission
-        if problem.is_public or problem.testers.filter(id=profile.id).exists():
-            if Submission.objects.filter(
-                user_id=profile.id,
-                result="AC",
-                problem_id=problem.id,
-                points=problem.points,
-            ).exists():
-                return submission
-        if hasattr(
-            submission, "contest"
-        ) and submission.contest.participation.contest.is_editable_by(
-            self.request.user
-        ):
+        if submission.is_accessible_by(self.request.profile):
             return submission
 
         raise PermissionDenied()
@@ -483,19 +459,9 @@ class SubmissionsListBase(DiggPaginatorMixin, TitleMixin, ListView):
         authenticated = self.request.user.is_authenticated
         context["dynamic_update"] = False
         context["show_problem"] = self.show_problem
-        context["completed_problem_ids"] = (
-            user_completed_ids(self.request.profile) if authenticated else []
-        )
-        context["editable_problem_ids"] = (
-            user_editable_ids(self.request.profile) if authenticated else []
-        )
-        context["tester_problem_ids"] = (
-            user_tester_ids(self.request.profile) if authenticated else []
-        )
-
+        context["profile"] = self.request.profile
         context["all_languages"] = Language.objects.all().values_list("key", "name")
         context["selected_languages"] = self.selected_languages
-
         context["all_statuses"] = self.get_searchable_status_codes()
         context["selected_statuses"] = self.selected_statuses
 
@@ -779,19 +745,10 @@ def single_submission(request, submission_id, show_problem=True):
         "submission/row.html",
         {
             "submission": submission,
-            "completed_problem_ids": user_completed_ids(request.profile)
-            if authenticated
-            else [],
-            "editable_problem_ids": user_editable_ids(request.profile)
-            if authenticated
-            else [],
-            "tester_problem_ids": user_tester_ids(request.profile)
-            if authenticated
-            else [],
             "show_problem": show_problem,
             "problem_name": show_problem
             and submission.problem.translated_name(request.LANGUAGE_CODE),
-            "profile_id": request.profile.id if authenticated else 0,
+            "profile": request.profile if authenticated else None,
         },
     )
 
@@ -1010,9 +967,6 @@ class UserContestSubmissionsAjax(UserContestSubmissions):
         context["contest"] = self.contest
         context["problem"] = self.problem
         context["profile"] = self.profile
-        context["profile_id"] = (
-            self.request.profile.id if self.request.profile else None
-        )
 
         contest_problem = self.contest.contest_problems.get(problem=self.problem)
         filtered_submissions = []
diff --git a/resources/blog.scss b/resources/blog.scss
index ad21448..4c57cfe 100644
--- a/resources/blog.scss
+++ b/resources/blog.scss
@@ -229,7 +229,6 @@
 .show-more {
     display: flex;
     color: black;
-    font-style: italic;
     font-size: 16px;
     font-weight: 700;
     padding: 0px 12px;
diff --git a/templates/feed/has_next.html b/templates/feed/has_next.html
index 9cc45c9..f26caea 100644
--- a/templates/feed/has_next.html
+++ b/templates/feed/has_next.html
@@ -1,4 +1,4 @@
 <div class="has_next" style="display: none;" value="{{1 if has_next_page else 0}}"></div>
 {% if has_next_page %}
-  <button class="view-next-page btn-green small">{{_('View more')}}</button>
+  <button class="view-next-page">{{_('View more')}}</button>
 {% endif %}
\ No newline at end of file
diff --git a/templates/submission/row.html b/templates/submission/row.html
index 1c4d8d7..73523f6 100644
--- a/templates/submission/row.html
+++ b/templates/submission/row.html
@@ -1,4 +1,4 @@
-{% set can_view = submission_layout(submission, profile_id, request.user, editable_problem_ids, completed_problem_ids, tester_problem_ids) %}
+{% set can_view = submission.is_accessible_by(profile) %}
 <div class="sub-result {{ submission._result_class if in_hidden_subtasks_contest else submission.result_class }}">
   <div class="score">
     {%- if submission.is_graded -%}
diff --git a/templates/submission/user-ajax.html b/templates/submission/user-ajax.html
index b03248a..d060ede 100644
--- a/templates/submission/user-ajax.html
+++ b/templates/submission/user-ajax.html
@@ -1,5 +1,5 @@
 <h4>
-  {{_('Contest submissions of')}} {{link_user(profile)}}  <a href="{{url('contest_user_submissions', contest.key, profile.user.username, problem.code)}}">#</a>
+  {{_('Contest submissions of')}} {{link_user(profile)}}  <a href="{{url('contest_user_submissions', contest.key, profile.username, problem.code)}}">#</a>
 </h4>
 <hr>
 {% if best_subtasks and subtasks %}
@@ -19,7 +19,7 @@
           </td>
         {% endif %}
         {% if cur_subtask.submission %}
-          {% set can_view = submission_layout(cur_subtask.submission, profile_id, request.user, editable_problem_ids, completed_problem_ids, tester_problem_ids) %}
+          {% set can_view = cur_subtask.submission.is_accessible_by(profile) %}
           {% if can_view %}
             <td>
               → <a href="{{url('submission_status', cur_subtask.submission.id)}}">{{ cur_subtask.submission.id }}</a>
@@ -43,7 +43,7 @@
   <table class="lightbox-submissions"><tbody>
     {% for submission in submissions %}
       <tr>
-        {% set can_view = submission_layout(submission, profile_id, request.user, editable_problem_ids, completed_problem_ids, tester_problem_ids) %}
+        {% set can_view = submission.is_accessible_by(profile) %}
         <td class="lightbox-submissions-time">
           {% if submission.contest_time %}
             {{submission.contest_time}}