diff --git a/NetSNMP.cabal b/NetSNMP.cabal
--- a/NetSNMP.cabal
+++ b/NetSNMP.cabal
@@ -1,6 +1,6 @@
 
 Name:               NetSNMP
-Version:            0.1.0
+Version:            0.1.1
 Synopsis:           Bindings for net-snmp's C API for clients
 Description:        Network.Protocol.NetSNMP is a partial binding to the
                     library portion of the net-snmp package.  It uses the
@@ -22,7 +22,7 @@
 
 library
   hs-source-dirs:   src
-  build-depends:    base
+  build-depends:    base >=4 && <5
   build-tools:      hsc2hs
   exposed-modules:  Network.Protocol.NetSNMP
   extensions:       ForeignFunctionInterface, CPP, EmptyDataDecls
diff --git a/src/Network/Protocol/NetSNMP.hsc b/src/Network/Protocol/NetSNMP.hsc
--- a/src/Network/Protocol/NetSNMP.hsc
+++ b/src/Network/Protocol/NetSNMP.hsc
@@ -136,7 +136,7 @@
 -- |An SNMP value together with its OID.  Returned by the query
 --     routines 'snmpGet', 'snmpNext', and 'snmpWalk'.
 data SnmpResult  = SnmpResult {
-  oid :: String,               -- ^Dotted-decimal ObjectId of the value
+  oid   :: String,             -- ^Dotted-decimal ObjectId of the value
   value :: ASNValue            -- ^Typed representation of the value
   } deriving (Eq, Show)
 
@@ -300,12 +300,10 @@
   -> Community   -- ^SNMP community (password)
   -> String      -- ^OID to be queried
   -> IO (Either String SnmpResult)
-snmpGet version hostname community oid = runTrouble $ do
-  session <- readyCommunitySession version hostname community
-  let get = mkSnmpGet snmp_msg_get session
-  result <- get oid
-  closeSession session
-  return result
+snmpGet version hostname community oid = runTrouble $ bracketT
+  (readyCommunitySession version hostname community) -- session
+  closeSession
+  (flip (mkSnmpGet snmp_msg_get) oid)
 
 -- |Simple community-authenticated SNMP getnext.  Returns the first object
 --     after the OID queried, or a descriptive error message.
@@ -322,12 +320,10 @@
   -> Community   -- ^SNMP community (password)
   -> String      -- ^OID to be queried
   -> IO (Either String SnmpResult)
-snmpNext version hostname community oid = runTrouble $ do
-  session <- readyCommunitySession version hostname community
-  let next = mkSnmpGet snmp_msg_getnext session
-  result <- next oid
-  closeSession session
-  return result
+snmpNext version hostname community oid = runTrouble $ bracketT
+  (readyCommunitySession version hostname community) -- session
+  closeSession
+  (flip (mkSnmpGet snmp_msg_getnext) oid)
 
 -- |Simple community-authenticated SNMP walk.  Returns a list of objects,
 --     starting with the object after the OID queried, and continuing
@@ -349,21 +345,18 @@
   -> Community   -- ^SNMP community (password)
   -> String      -- ^OID to be queried
   -> IO (Either String [SnmpResult])
-snmpWalk version hostname community walkoid = runTrouble $ do
-    session <- readyCommunitySession version hostname community
-    let next = mkSnmpGet snmp_msg_getnext session
-    result <- go next walkoid
-    closeSession session
-    return result
+snmpWalk version hostname community walkoid = runTrouble $ bracketT
+    (readyCommunitySession version hostname community) -- session
+    closeSession
+    (go walkoid . mkSnmpGet snmp_msg_getnext)
   where
-    go :: (String -> Trouble SnmpResult) -> String -> Trouble [SnmpResult]
-    -- go next oid = flip catchT (const $ return []) $ do
-    go next oid = do
+    go :: String -> (String -> Trouble SnmpResult) -> Trouble [SnmpResult]
+    go oid next = do
       v@(SnmpResult nextoid val) <- next oid
       case () of
         _ | nextoid == oid -> return [] -- throwT "end of mib" -- return []
           | walkoid `isPrefixOf` nextoid -> do
-            vs <- go next nextoid
+            vs <- go nextoid next
             return (v:vs)
           | otherwise -> return [] -- throwT "end of walk" -- return []
 
@@ -824,6 +817,17 @@
   r <- runTrouble m
   case r of (Left s)  -> runTrouble (h s)
             (Right v) -> return r
+
+handleT :: (String -> Trouble a) -> Trouble a -> Trouble a
+handleT = flip catchT
+
+bracketT :: Trouble a -> (a -> Trouble b) -> (a -> Trouble c) -> Trouble c
+bracketT before after thing = do
+  a <- before
+  handleT (\s -> after a >> throwT s) $ do
+    result <- thing a
+    after a
+    return result
 
 -- Routines to 'hoist' anything with IO return type into the
 -- equivalent with (Trouble a) ie. IO (Either String a) return type.