diff --git a/.env.sample b/.env.sample
index c381797..29c0208 100644
--- a/.env.sample
+++ b/.env.sample
@@ -11,6 +11,7 @@ GH_SECRET=moresecrets
 GH_ORG=29205
 GH_ORG_NAME=localytics
 GH_REPOS=repo1,repo2
+GH_COMMENT=true
 LANGS=rb,js;rb
 MODE=proxy
 MONGO_URI=mongodb://heroku_appxyz:abcd@ds031978.mongolab.com:31978/heroku_appxyz
diff --git a/app.json b/app.json
index b286f75..a00c77d 100644
--- a/app.json
+++ b/app.json
@@ -43,6 +43,10 @@
     "GH_REPOS": {
       "description": "Comma-separated Github repo names to track coverage for"
     },
+    "GH_COMMENT": {
+      "description": "Whether to comment on GitHub PRs",
+      "value": "true"
+    },
     "LANGS": {
       "description": "Comma-separated language file extensions (such as rb,js) to collect coverage for (semicolon-separated for multiple repos, one per repo)"
     },
diff --git a/app.py b/app.py
index e4bd89b..4b0773d 100644
--- a/app.py
+++ b/app.py
@@ -18,10 +18,12 @@
 LANGS = dict(zip(constants.get('GH_REPOS').split(','), constants.get('LANGS').split(';')))
 CURRENT = dict(zip(constants.get('GH_REPOS').split(','), constants.get('CURRENT').split(';')))
 
-try:
-  s3 = S3(constants.get('AWS_ACCESS_KEY'), constants.get('AWS_SECRET_KEY'), constants.get('AWS_BUCKET'))
-except:
-  s3 = None
+s3 = None
+if constants.get('GH_COMMENT').lower() == 'true':
+  try:
+    s3 = S3(constants.get('AWS_ACCESS_KEY'), constants.get('AWS_SECRET_KEY'), constants.get('AWS_BUCKET'))
+  except:
+    pass
 
 collections = zip(constants.get('GH_REPOS').split(','), constants.get('STORAGE_COLLECTIONS').split(','))
 storages = {}
@@ -50,7 +52,7 @@ def preprocess_request():
       return redirect(url_for('login_view'))
     if session.get('next'):
       return redirect(session.pop('next'))
-    if not s3:
+    if constants.get('GH_COMMENT').lower() == 'true' and not s3:
       flash('Your S3 keys are invalid!', 'danger')
       return 'Your S3 keys are invalid!'
 
diff --git a/helpers/githubbot.py b/helpers/githubbot.py
index 9a5e778..9b86e7f 100644
--- a/helpers/githubbot.py
+++ b/helpers/githubbot.py
@@ -14,6 +14,7 @@ def __init__(self, constants, repo_name, langs, current):
     self.current = current.split(',')
     self.constants = constants
     self.cache = defaultdict(dict)
+    self.post_comments = constants.get('GH_COMMENT').lower() == 'true'
 
   def past_comment(self, pr):
     cached = self.cache['comments'].get(pr.id)
@@ -96,6 +97,9 @@ def comment(self, pull_request_id, message, url, args, storage, coverage_diffs,
     self.post_comment(body, pr)
 
   def post_comment(self, body, pr):
+    if not self.post_comments:
+      return
+
     past_comment = self.past_comment(pr)
     if past_comment:
       past_comment.edit(body)