diff --git a/Hash2Pub.cabal b/Hash2Pub.cabal
index f7a1676..5e8d25d 100644
--- a/Hash2Pub.cabal
+++ b/Hash2Pub.cabal
@@ -47,7 +47,7 @@ extra-source-files:  CHANGELOG.md
 
 common deps
   build-depends:       base ^>=4.12.0.0, containers ^>=0.6.0.1, bytestring, utf8-string ^>=1.0.1.1, network ^>=2.8.0.1, time ^>=1.8.0.2, cmdargs ^>= 0.10, cryptonite ^>= 0.25, memory, async, stm, asn1-encoding, asn1-types, asn1-parse, publicsuffix, network-byte-order, safe, iproute, mtl, random, servant, servant-server, servant-client, warp, text, unordered-containers, hashable, unicode-transforms, http-client, http-types, unbounded-delays, dlist
-  ghc-options:         -Wall -Wpartial-fields
+  ghc-options:         -Wall -Wpartial-fields -O2
 
 
 
diff --git a/src/Hash2Pub/PostService.hs b/src/Hash2Pub/PostService.hs
index 7a082d0..608551f 100644
--- a/src/Hash2Pub/PostService.hs
+++ b/src/Hash2Pub/PostService.hs
@@ -121,8 +121,8 @@ instance DHT d => Service PostService d where
                 -- web server
                 (Warp.runSettings warpSettings $ postServiceApplication thisService)
                 $ concurrently
-                    -- background processing workers
-                    (launchWorkerThreads thisService)
+                    -- post queue processing
+                    (processIncomingPosts thisService)
                     -- statistics/ measurements
                     (launchStatsThreads thisService)
         -- update thread ID after fork
@@ -559,9 +559,9 @@ lookupTagSubscriptions :: Hashtag -> RingMap NodeID a -> Maybe a
 lookupTagSubscriptions tag = rMapLookup (hashtagToId tag)
 
 
--- normalise the unicode representation of a string to NFC and convert to lower case
+-- normalise the unicode representation of a string to NFC
 normaliseTag :: Text -> Text
-normaliseTag = Txt.toLower . Txt.fromStrict . normalize NFC . Txt.toStrict
+normaliseTag = Txt.fromStrict . normalize NFC . Txt.toStrict
 
 
 -- | convert a hashtag to its representation on the DHT
@@ -604,13 +604,6 @@ instance {-# OVERLAPPABLE #-} Read a => MimeUnrender PlainText a where
 -- TODO: make configurable
 numParallelDeliveries = 10
 
-launchWorkerThreads :: DHT d => PostService d -> IO ()
-launchWorkerThreads serv = concurrently_
-    (processIncomingPosts serv)
-    $ concurrently_
-        (fetchTagPosts serv)
-        (relayWorker serv)
-
 
 -- | process the pending relay inbox of incoming posts from the internal queue:
 -- Look up responsible relay node for given hashtag and forward post to it
@@ -643,7 +636,7 @@ processIncomingPosts serv = forever $ do
                   now <- getPOSIXTime
                   subscriptionStatus <- HMap.lookup (hashtagToId tag) <$> readTVarIO (ownSubscriptions serv)
                   -- if not yet subscribed or subscription expires within 2 minutes, (re)subscribe to tag
-                  when (maybe True (\subLease -> now - subLease < 120) subscriptionStatus) $
+                  when (maybe False (\subLease -> now - subLease < 120) subscriptionStatus) $
                       void $ clientSubscribeTo serv tag
 
                   -- for evaluation, return the tag of the successfully forwarded post