diff --git a/AWS.hs b/AWS.hs
--- a/AWS.hs
+++ b/AWS.hs
@@ -24,7 +24,7 @@
 -- >     cred <- loadCredential
 -- >     doc <- runResourceT $
 -- >         runEC2 cred $
--- >             Util.asList $ describeInstances [] []
+-- >             Util.list $ describeInstances [] []
 -- >     print doc
 -- >     putStr "Length: "
 -- >     print $ length doc
@@ -38,6 +38,7 @@
       -- * Environment
     , AWS
     , AWSException(..)
+    , getLastRequestId
     ) where
 
 import AWS.Credential
diff --git a/AWS/Class.hs b/AWS/Class.hs
--- a/AWS/Class.hs
+++ b/AWS/Class.hs
@@ -11,6 +11,8 @@
     , runAWS
     , AWSException(..)
     , AWSContext(..)
+    , getLastRequestId
+    , monadThrow
     ) where
 
 import Control.Monad.State (StateT(..), MonadState)
@@ -18,7 +20,7 @@
 import Control.Monad.Reader (ReaderT(..), MonadReader)
 import qualified Control.Monad.Reader as R
 import Control.Applicative
-import Control.Monad (liftM)
+import Control.Monad
 import Control.Monad.Base (MonadBase)
 import Control.Monad.IO.Class (MonadIO, liftIO)
 import Control.Monad.Trans.Class (MonadTrans, lift)
@@ -31,6 +33,7 @@
     )
 import Control.Exception (Exception)
 import Data.Typeable (Typeable)
+import Data.Conduit (MonadThrow, monadThrow)
 
 import qualified Network.HTTP.Conduit as HTTP
 import Data.Text (Text)
@@ -41,11 +44,15 @@
 
 data AWSException
     = ClientError
-        { errorStatus :: Int
+        { errorAction :: ByteString
+        , errorStatus :: Int
         , errorCode :: Text
         , errorMessage :: Text
         , errorRequestId :: Text
         } -- ^ This error is caused by client requests.
+    | ResponseParseError Text
+    | TextConversionException Text
+        -- ^ parse error: cannot convert Text to oher data type.
     | NextToken Text -- ^ This response has next token.
   deriving (Show, Typeable)
 
@@ -100,3 +107,6 @@
     R.runReaderT
         (S.evalStateT (runAWST app) $ ctx mgr)
         cred
+
+getLastRequestId :: (Monad m, Functor m) => AWS AWSContext m (Maybe Text)
+getLastRequestId = lastRequestId <$> S.get
diff --git a/AWS/CloudWatch.hs b/AWS/CloudWatch.hs
--- a/AWS/CloudWatch.hs
+++ b/AWS/CloudWatch.hs
@@ -19,7 +19,7 @@
 import Data.Monoid ((<>))
 
 import AWS.Class
-import AWS.Util
+import AWS.Lib.Query (textToBS)
 
 import AWS
 import AWS.CloudWatch.Internal
diff --git a/AWS/CloudWatch/Metric.hs b/AWS/CloudWatch/Metric.hs
--- a/AWS/CloudWatch/Metric.hs
+++ b/AWS/CloudWatch/Metric.hs
@@ -61,13 +61,13 @@
 getMetricStatistics ds start end mn ns pe sts unit =
     cloudWatchQuery "GetMetricStatistics" params $ (,)
         <$> members "Datapoints" (Datapoint
-            <$> getF "Timestamp" textToTime
-            <*> getM "SampleCount" (textToDouble <$>)
+            <$> getT "Timestamp"
+            <*> getT "SampleCount"
             <*> getT "Unit"
-            <*> getM "Minimum" (textToDouble <$>)
-            <*> getM "Maximum" (textToDouble <$>)
-            <*> getM "Sum" (textToDouble <$>)
-            <*> getM "Average" (textToDouble <$>)
+            <*> getT "Minimum"
+            <*> getT "Maximum"
+            <*> getT "Sum"
+            <*> getT "Average"
             )
         <*> getT "Label"
   where
diff --git a/AWS/EC2.hs b/AWS/EC2.hs
--- a/AWS/EC2.hs
+++ b/AWS/EC2.hs
@@ -6,6 +6,7 @@
       EC2
     , runEC2
     , setRegion
+    , setEndpoint
       -- * Instances
     , module AWS.EC2.Instance
       -- * Images
@@ -20,6 +21,8 @@
     , module AWS.EC2.KeyPair
       -- * SecurityGroups
     , module AWS.EC2.SecurityGroup
+      -- * NetworkInterface
+    , module AWS.EC2.NetworkInterface
       -- * Placements
     , module AWS.EC2.Region
     , module AWS.EC2.AvailabilityZone
@@ -36,9 +39,10 @@
 import Control.Monad.Trans.Control (MonadBaseControl)
 import qualified Control.Monad.State as State
 import Data.Text (Text)
+import Data.ByteString (ByteString)
 
-import AWS.Util
 import AWS.Class
+import AWS.Lib.Query (textToBS)
 import AWS.EC2.Internal
 import AWS.EC2.Types
 import qualified AWS.EC2.Util as Util
@@ -57,18 +61,23 @@
 import AWS.EC2.Subnets
 import AWS.EC2.Acl
 import AWS.EC2.RouteTable
+import AWS.EC2.NetworkInterface
 
--- | set endpoint to EC2 context.
+-- | set endpoint to EC2 context by giving the EC2 region.
 setRegion
     :: (MonadResource m, MonadBaseControl IO m)
     => Text -- ^ RegionName
     -> EC2 m ()
 setRegion name = do
     region <- Util.head $ describeRegions [name] []
-    ctx <- State.get
-    maybe
-        (fail "region not found")
-        (\r -> State.put ctx { endpoint = f r })
-        region
+    maybe (fail "region not found") (setEndpoint . g) region
   where
-    f = textToBS . regionEndpoint
+    g = textToBS . regionEndpoint
+
+-- | set endpoint to EC2 context.
+setEndpoint :: (MonadResource m, MonadBaseControl IO m)
+    => ByteString -- ^ ec2 endpoint domain <http://docs.amazonwebservices.com/general/latest/gr/rande.html>
+    -> EC2 m ()
+setEndpoint endpoint = do
+    ctx <- State.get
+    State.put ctx { endpoint = endpoint }
diff --git a/AWS/EC2/Acl.hs b/AWS/EC2/Acl.hs
--- a/AWS/EC2/Acl.hs
+++ b/AWS/EC2/Acl.hs
@@ -16,7 +16,6 @@
 import Control.Monad.Trans.Control (MonadBaseControl)
 import Control.Applicative
 
-import AWS.EC2.Convert
 import AWS.EC2.Internal
 import AWS.EC2.Types
 import AWS.EC2.Query
@@ -42,20 +41,20 @@
 networkAclSink = NetworkAcl
     <$> getT "networkAclId"
     <*> getT "vpcId"
-    <*> getF "default" textToBool
+    <*> getT "default"
     <*> itemsSet "entrySet" (NetworkAclEntry
-        <$> getF "ruleNumber" textToInt
-        <*> getF "protocol" textToInt
-        <*> getF "ruleAction" networkAclRuleAction
-        <*> getF "egress" textToBool
+        <$> getT "ruleNumber"
+        <*> getT "protocol"
+        <*> getT "ruleAction"
+        <*> getT "egress"
         <*> getT "cidrBlock"
         <*> elementM "icmpTypeCode" (IcmpTypeCode
-            <$> getF "code" textToInt
-            <*> getF "type" textToInt
+            <$> getT "code"
+            <*> getT "type"
             )
         <*> elementM "portRange" (PortRange
-            <$> getF "from" textToInt
-            <*> getF "to" textToInt))
+            <$> getT "from"
+            <*> getT "to"))
     <*> itemsSet "associationSet" (NetworkAclAssociation
         <$> getT "networkAclAssociationId"
         <*> getT "networkAclId"
@@ -98,7 +97,7 @@
     => NetworkAclEntryRequest
     -> EC2 m Bool
 createNetworkAclEntry req =
-    ec2Query "CreateNetworkAclEntry" params returnBool
+    ec2Query "CreateNetworkAclEntry" params $ getT "return"
   where
     params = reqToParams req
 
@@ -145,7 +144,7 @@
     -> Bool -- ^ Egress
     -> EC2 m Bool
 deleteNetworkAclEntry aclid rule egress =
-    ec2Query "DeleteNetworkAclEntry" params returnBool
+    ec2Query "DeleteNetworkAclEntry" params $ getT "return"
   where
     params =
         [ ValueParam "NetworkAclId" aclid
@@ -158,6 +157,6 @@
     => NetworkAclEntryRequest
     -> EC2 m Bool
 replaceNetworkAclEntry req =
-    ec2Query "ReplaceNetworkAclEntry" params returnBool
+    ec2Query "ReplaceNetworkAclEntry" params $ getT "return"
   where
     params = reqToParams req
diff --git a/AWS/EC2/Address.hs b/AWS/EC2/Address.hs
--- a/AWS/EC2/Address.hs
+++ b/AWS/EC2/Address.hs
@@ -11,13 +11,12 @@
     ) where
 
 import Data.Text (Text)
-
+import Data.IP (IPv4)
 import Data.XML.Types (Event)
 import Data.Conduit
 import Control.Monad.Trans.Control (MonadBaseControl)
 import Control.Applicative
 
-import AWS.EC2.Convert
 import AWS.EC2.Internal
 import AWS.EC2.Types
 import AWS.EC2.Query
@@ -44,13 +43,13 @@
     addressSet :: MonadThrow m => GLConduit Event m Address
     addressSet = itemConduit "addressesSet" $ Address
         <$> getT "publicIp"
-        <*> getMT "allocationId"
-        <*> getM "domain" addressDomain'
-        <*> getMT "instanceId"
-        <*> getMT "associationId"
-        <*> getMT "networkInterfaceId"
-        <*> getMT "networkInterfaceOwnerId"
-        <*> getMT "privateIpAddress"
+        <*> getT "allocationId"
+        <*> getT "domain"
+        <*> getT "instanceId"
+        <*> getT "associationId"
+        <*> getT "networkInterfaceId"
+        <*> getT "networkInterfaceOwnerId"
+        <*> getT "privateIpAddress"
 
 -----------------------------------------------------
 -- AllocateAddress
@@ -63,8 +62,8 @@
     ec2Query "AllocateAddress" params $
         AllocateAddress
         <$> getT "publicIp"
-        <*> getM "domain" addressDomain'
-        <*> getMT "allocationId"
+        <*> getT "domain"
+        <*> getT "allocationId"
   where
     params = if isVpc then [ValueParam "Domain" "vpc"] else []
 
@@ -73,14 +72,14 @@
 -----------------------------------------------------
 releaseAddress
     :: (MonadResource m, MonadBaseControl IO m)
-    => Maybe Text -- ^ PublicIp
+    => Maybe IPv4 -- ^ PublicIp
     -> Maybe Text -- ^ AllocationId
     -> EC2 m EC2Return
 releaseAddress addr allocid = do
-    ec2Query "ReleaseAddress" params $ getF "return" ec2Return
+    ec2Query "ReleaseAddress" params $ getT "return"
   where
     params = maybeParams
-        [ ("PublicIp", addr)
+        [ ("PublicIp", toText <$> addr)
         , ("AllocationId", allocid)
         ]
 
@@ -92,15 +91,15 @@
     => AssociateAddressRequest
     -> EC2 m (Bool, Maybe Text)
 associateAddress param = ec2Query "AssociateAddress" params $
-    (,) <$> getF "return" textToBool
-        <*> getMT "associationId"
+    (,) <$> getT "return"
+        <*> getT "associationId"
   where
     params = associateAddressParam param
 
 associateAddressParam
     :: AssociateAddressRequest -> [QueryParam]
 associateAddressParam (AssociateAddressRequestEc2 ip iid) =
-    [ ValueParam "PublicIp" ip
+    [ ValueParam "PublicIp" $ toText ip
     , ValueParam "InstanceId" iid
     ]
 associateAddressParam
@@ -109,7 +108,7 @@
     ++ maybeParams
         [ ("InstanceId", iid)
         , ("NetworkInterfaceId", nid)
-        , ("PrivateIpAddress", pip)
+        , ("PrivateIpAddress", toText <$> pip)
         , ("AllowReassociation", boolToText <$> ar)
         ]
 
@@ -119,9 +118,9 @@
     -> EC2 m Bool
 disassociateAddress param =
     ec2Query "DisassociateAddress" (p param)
-        $ getF "return" textToBool
+        $ getT "return"
   where
     p (DisassociateAddressRequestEc2 pip)
-        = [ValueParam "PublicIp" pip]
+        = [ValueParam "PublicIp" $ toText pip]
     p (DisassociateAddressRequestVpc aid)
-        = [ValueParam "AssociationId" aid]
+        = [ValueParam "AssociationId" $ toText aid]
diff --git a/AWS/EC2/Convert.hs b/AWS/EC2/Convert.hs
deleted file mode 100644
--- a/AWS/EC2/Convert.hs
+++ /dev/null
@@ -1,200 +0,0 @@
-{-# LANGUAGE RankNTypes, TemplateHaskell #-}
-
-module AWS.EC2.Convert
-    where
-
-import Data.Text (Text)
-
-import AWS.Util
-import AWS.Lib.Convert
-import AWS.EC2.Types
-
-mkConvertFunc
-    "imageState"
-    ''ImageState
-    ["available", "pending", "failed"]
-
-mkConvertFunc
-    "productCodeType'"
-    ''ProductCodeType
-    ["devpay", "marketplace"]
-
-mkConvertFunc
-    "imageType"
-    ''ImageType
-    ["machine", "kernel", "ramdisk"]
-
-platform :: Maybe Text -> Platform
-platform Nothing   = PlatformOther
-platform (Just t)
-    | t == "windows" = PlatformWindows
-    | otherwise      = PlatformOther
-
-mkConvertFunc
-    "rootDeviceType"
-    ''RootDeviceType
-    ["ebs", "instance-store"]
-
-volumeType :: Text -> Maybe Int -> VolumeType
-volumeType t Nothing  | t == "standard" = VolumeTypeStandard
-volumeType t (Just i) | t == "io1"      = VolumeTypeIO1 i
-volumeType t _ = err "volume type" t
-
-mkConvertFunc
-    "virtualizationType"
-    ''VirtualizationType ["paravirtual", "hvm"]
-
-mkConvertFunc "hypervisor" ''Hypervisor ["ovm", "xen"]
-
-mkConvertFunc
-    "instanceStatusEventCode'"
-    ''InstanceStatusEventCode
-    [ "instance-reboot"
-    , "instance-stop"
-    , "system-reboot"
-    , "instance-retirement"
-    ]
-
-mkConvertFunc
-    "instanceStatusTypeStatus'"
-    ''InstanceStatusTypeStatus
-    ["ok", "impaired", "insufficient-data", "not-applicable"]
-
-instanceStateCodes :: [(Int, InstanceState)]
-instanceStateCodes =
-    [ (0, InstanceStatePending)
-    , (16, InstanceStateRunning)
-    , (32, InstanceStateShuttingDown)
-    , (48, InstanceStateTerminated)
-    , (64, InstanceStateStopping)
-    , (80, InstanceStateStopped)
-    ]
-
-codeToState :: Int -> InstanceState
-codeToState code = maybe
-    (InstanceStateUnknown code)
-    id
-    (lookup code instanceStateCodes)
-
-mkConvertFunc
-    "instanceMonitoringState"
-    ''InstanceMonitoringState
-    ["disabled", "enabled", "pending"]
-
-mkConvertFunc "architecture" ''Architecture ["i386", "x86_64"]
-
-addressDomain' :: Maybe Text -> AddressDomain
-addressDomain' Nothing = AddressDomainStandard
-addressDomain' (Just t)
-    | t == "standard" = AddressDomainStandard
-    | t == "vpc"      = AddressDomainVPC
-    | otherwise       = err "address domain" t
-
-ec2Return :: Text -> EC2Return
-ec2Return t
-    | t == "true" = EC2Success
-    | otherwise   = EC2Error t
-
-mkConvertFunc
-    "snapshotStatus'"
-    ''SnapshotStatus
-    ["pending", "completed", "error"]
-
-mkConvertFunc
-    "volumeStatus'"
-    ''VolumeState
-    [ "creating"
-    , "available"
-    , "in-use"
-    , "deleting"
-    , "deleted"
-    , "error"]
-
-mkConvertFunc
-    "attachmentSetItemResponseStatus'"
-    ''AttachmentSetItemResponseStatus
-    ["attaching", "attached", "detaching", "detached"]
-
-mkConvertFunc
-    "shutdownBehavior"
-    ''ShutdownBehavior
-    ["stop", "terminate"]
-
-mkConvertFunc
-    "vpnConnectionState'"
-    ''VpnConnectionState
-    ["pending", "available", "deleting", "deleted"]
-
-mkConvertFunc
-    "vpnTunnelTelemetryStatus'"
-    ''VpnTunnelTelemetryStatus
-    ["UP", "DOWN"]
-
-mkConvertFunc
-    "vpnStaticRouteSource'"
-    ''VpnStaticRouteSource
-    ["Static"]
-
-mkConvertFunc
-    "vpnStaticRouteState'"
-    ''VpnStaticRouteState
-    ["pending", "available", "deleting", "deleted"]
-
-instanceLifecycle :: Maybe Text -> InstanceLifecycle
-instanceLifecycle Nothing = LifecycleNone
-instanceLifecycle (Just t)
-    | t == "spot"   = LifecycleSpot
-    | otherwise     = err "lifecycle" t
-
-mkConvertFunc
-    "subnetState'"
-    ''SubnetState
-    ["pending", "available"]
-
-mkConvertFunc
-    "volumeStatusInfoStatus'"
-    ''VolumeStatusInfoStatus
-    ["ok", "impaired", "insufficient-data"]
-
-mkConvertFunc
-    "networkAclRuleAction"
-    ''NetworkAclRuleAction
-    ["allow", "deny"]
-
-mkConvertFunc
-    "routeState'"
-    ''RouteState
-    ["active", "blackhole"]
-
-mkConvertFunc
-    "routeOrigin'"
-    ''RouteOrigin
-    [ "CreateRouteTable"
-    , "CreateRoute"
-    , "EnableVgwRoutePropagation"
-    ]
-
-mkConvertFunc
-    "vpcState'"
-    ''VpcState
-    ["pending", "available"]
-
-mkConvertFunc
-    "vpnGatewayState'"
-    ''VpnGatewayState
-    ["pending", "available", "deleting", "deleted"]
-
-mkConvertFunc
-    "attachmentState'"
-    ''AttachmentState
-    ["attaching", "attached", "detaching", "detached"]
-
-mkConvertFunc
-    "customerGatewayState'"
-    ''CustomerGatewayState
-    ["pending", "available", "deleting", "deleted"]
-
-mkConvertFunc
-    "internetGatewayAttachmentState'"
-    ''InternetGatewayAttachmentState
-    ["attaching", "attached", "detaching", "detached", "available"]
diff --git a/AWS/EC2/Image.hs b/AWS/EC2/Image.hs
--- a/AWS/EC2/Image.hs
+++ b/AWS/EC2/Image.hs
@@ -17,7 +17,6 @@
 import Control.Applicative
 import Control.Monad (join)
 
-import AWS.EC2.Convert
 import AWS.EC2.Internal
 import AWS.EC2.Types
 import AWS.EC2.Params
@@ -48,38 +47,38 @@
 imageItem = Image
     <$> getT "imageId"
     <*> getT "imageLocation"
-    <*> getF "imageState" imageState
+    <*> getT "imageState"
     <*> getT "imageOwnerId"
-    <*> getF "isPublic" textToBool
+    <*> getT "isPublic"
     <*> productCodeSink
     <*> getT "architecture"
-    <*> getF "imageType" imageType
-    <*> getMT "kernelId"
-    <*> getMT "ramdiskId"
-    <*> getM "platform" platform
+    <*> getT "imageType"
+    <*> getT "kernelId"
+    <*> getT "ramdiskId"
+    <*> getT "platform"
     <*> stateReasonSink
-    <*> getM "viridianEnabled" (textToBool <$>)
-    <*> getMT "imageOwnerAlias"
-    <*> getM "name" orEmpty
-    <*> getM "description" orEmpty
+    <*> getT "viridianEnabled"
+    <*> getT "imageOwnerAlias"
+    <*> getT "name"
+    <*> getT "description"
     <*> itemsSet "billingProducts" (getT "billingProduct")
-    <*> getF "rootDeviceType" rootDeviceType
-    <*> getMT "rootDeviceName"
+    <*> getT "rootDeviceType"
+    <*> getT "rootDeviceName"
     <*> blockDeviceMappingSink
-    <*> getF "virtualizationType" virtualizationType
+    <*> getT "virtualizationType"
     <*> resourceTagSink
-    <*> getF "hypervisor" hypervisor
+    <*> getT "hypervisor"
 
 blockDeviceMappingSink :: MonadThrow m => GLSink Event m [BlockDeviceMapping]
 blockDeviceMappingSink = itemsSet "blockDeviceMapping" (
     BlockDeviceMapping
     <$> getT "deviceName"
-    <*> getMT "virtualName"
+    <*> getT "virtualName"
     <*> elementM "ebs" (
         EbsBlockDevice
-        <$> getMT "snapshotId"
-        <*> getF "volumeSize" textToInt
-        <*> getF "deleteOnTermination" textToBool
+        <$> getT "snapshotId"
+        <*> getT "volumeSize"
+        <*> getT "deleteOnTermination"
         <*> volumeTypeSink
         )
     )
@@ -133,7 +132,7 @@
     => Text -- ^ ImageId
     -> EC2 m Bool
 deregisterImage iid =
-    ec2Query "DeregisterImage" params returnBool
+    ec2Query "DeregisterImage" params $ getT "return"
   where
     params = [ValueParam "ImageId" iid]
 
@@ -157,7 +156,7 @@
         <*> getMMT "description"
         <*> blockDeviceMappingSink
   where
-    getMMT name = join <$> elementM name (getMT "value")
+    getMMT name = join <$> elementM name (getT "value")
     params = [ ValueParam "ImageId" iid
              , ValueParam "Attribute" param
              ]
diff --git a/AWS/EC2/Instance.hs b/AWS/EC2/Instance.hs
--- a/AWS/EC2/Instance.hs
+++ b/AWS/EC2/Instance.hs
@@ -21,10 +21,11 @@
 import Data.Conduit
 import Control.Monad.Trans.Control (MonadBaseControl)
 import Control.Applicative
-import Data.Maybe (fromJust)
+import Data.Maybe (fromMaybe, fromJust)
 import qualified Data.Map as Map
+import Data.Monoid
+import Control.Monad
 
-import AWS.EC2.Convert
 import AWS.EC2.Internal
 import AWS.EC2.Types
 import AWS.EC2.Params
@@ -57,12 +58,7 @@
     <*> getT "ownerId"
     <*> groupSetSink
     <*> instanceSetSink
-    <*> getMT "requesterId"
-
-groupSetSink :: MonadThrow m => GLSink Event m [Group]
-groupSetSink = itemsSet "groupSet" $ Group
-    <$> getT "groupId"
-    <*> getT "groupName"
+    <*> getT "requesterId"
 
 instanceSetSink :: MonadThrow m
     => GLSink Event m [Instance]
@@ -74,45 +70,45 @@
     <*> getT "privateDnsName"
     <*> getT "dnsName"
     <*> getT "reason"
-    <*> getMT "keyName"
+    <*> getT "keyName"
     <*> getT "amiLaunchIndex"
     <*> productCodeSink
     <*> getT "instanceType"
-    <*> getF "launchTime" textToTime
+    <*> getT "launchTime"
     <*> element "placement" (
         Placement
         <$> getT "availabilityZone"
         <*> getT "groupName"
         <*> getT "tenancy"
         )
-    <*> getMT "kernelId"
-    <*> getMT "ramdiskId"
-    <*> getMT "platform"
-    <*> element "monitoring" (getF "state" instanceMonitoringState)
-    <*> getMT "subnetId"
-    <*> getMT "vpcId"
-    <*> getMT "privateIpAddress"
-    <*> getMT "ipAddress"
-    <*> getM "sourceDestCheck" (textToBool <$>)
+    <*> getT "kernelId"
+    <*> getT "ramdiskId"
+    <*> getT "platform"
+    <*> element "monitoring" (getT "state")
+    <*> getT "subnetId"
+    <*> getT "vpcId"
+    <*> getT "privateIpAddress"
+    <*> getT "ipAddress"
+    <*> getT "sourceDestCheck"
     <*> groupSetSink
     <*> stateReasonSink
-    <*> getF "architecture" architecture
-    <*> getF "rootDeviceType" rootDeviceType
-    <*> getMT "rootDeviceName"
+    <*> getT "architecture"
+    <*> getT "rootDeviceType"
+    <*> getT "rootDeviceName"
     <*> instanceBlockDeviceMappingsSink
-    <*> getM "instanceLifecycle" instanceLifecycle
-    <*> getMT "spotInstanceRequestId"
-    <*> getF "virtualizationType" virtualizationType
+    <*> getT "instanceLifecycle"
+    <*> getT "spotInstanceRequestId"
+    <*> getT "virtualizationType"
     <*> getT "clientToken"
     <*> resourceTagSink
-    <*> getF "hypervisor" hypervisor
+    <*> getT "hypervisor"
     <*> networkInterfaceSink
     <*> elementM "iamInstanceProfile" (
         IamInstanceProfile
         <$> getT "arn"
         <*> getT "id"
         )
-    <*> getF "ebsOptimized" textToBool
+    <*> getT "ebsOptimized"
 
 instanceBlockDeviceMappingsSink :: MonadThrow m
     => GLSink Event m [InstanceBlockDeviceMapping]
@@ -122,18 +118,32 @@
     <*> element "ebs" (
         EbsInstanceBlockDevice
         <$> getT "volumeId"
-        <*> getF "status" attachmentSetItemResponseStatus'
-        <*> getF "attachTime" textToTime
-        <*> getF "deleteOnTermination" textToBool
+        <*> getT "status"
+        <*> getT "attachTime"
+        <*> getT "deleteOnTermination"
         )
     )
 
+instanceStateCodes :: [(Int, InstanceState)]
+instanceStateCodes =
+    [ ( 0, InstanceStatePending)
+    , (16, InstanceStateRunning)
+    , (32, InstanceStateShuttingDown)
+    , (48, InstanceStateTerminated)
+    , (64, InstanceStateStopping)
+    , (80, InstanceStateStopped)
+    ]
+
+codeToState :: Int -> Text -> InstanceState
+codeToState code _name = fromMaybe
+    (InstanceStateUnknown code)
+    (lookup code instanceStateCodes)
+
 instanceStateSink :: MonadThrow m
     => Text -> GLSink Event m InstanceState
-instanceStateSink label = element label $
-    codeToState
-    <$> getF "code" textToInt
-    <* getT "name"
+instanceStateSink label = element label $ codeToState
+    <$> getT "code"
+    <*> getT "name"
 
 networkInterfaceSink :: MonadThrow m
     => GLSink Event m [InstanceNetworkInterface]
@@ -142,33 +152,33 @@
     <$> getT "networkInterfaceId"
     <*> getT "subnetId"
     <*> getT "vpcId"
-    <*> getM "description" orEmpty
+    <*> getT "description"
     <*> getT "ownerId"
     <*> getT "status"
     <*> getT "privateIpAddress"
-    <*> getMT "privateDnsName"
-    <*> getF "sourceDestCheck" textToBool
+    <*> getT "privateDnsName"
+    <*> getT "sourceDestCheck"
     <*> groupSetSink
     <*> element "attachment" (
-        NetworkInterfaceAttachment
+        InstanceNetworkInterfaceAttachment
         <$> getT "attachmentId"
-        <*> getF "deviceIndex" textToInt
+        <*> getT "deviceIndex"
         <*> getT "status"
-        <*> getF "attachTime" textToTime
-        <*> getF "deleteOnTermination" textToBool
+        <*> getT "attachTime"
+        <*> getT "deleteOnTermination"
         )
-    <*> niAssociationSink
+    <*> instanceNetworkInterfaceAssociationSink
     <*> itemsSet "privateIpAddressesSet" (
         InstancePrivateIpAddress
         <$> getT "privateIpAddress"
-        <*> getF "primary" textToBool
-        <*> niAssociationSink
+        <*> getT "primary"
+        <*> instanceNetworkInterfaceAssociationSink
         )
 
-niAssociationSink :: MonadThrow m
-    => GLSink Event m (Maybe NetworkInterfaceAssociation)
-niAssociationSink = elementM "association" $
-    NetworkInterfaceAssociation
+instanceNetworkInterfaceAssociationSink :: MonadThrow m
+    => GLSink Event m (Maybe InstanceNetworkInterfaceAssociation)
+instanceNetworkInterfaceAssociationSink = elementM "association" $
+    InstanceNetworkInterfaceAssociation
     <$> getT "publicIp"
     <*> getT "ipOwnerId"
 
@@ -201,10 +211,10 @@
         <*> getT "availabilityZone"
         <*> itemsSet "eventsSet" (
             InstanceStatusEvent
-            <$> getF "code" instanceStatusEventCode'
+            <$> getT "code"
             <*> getT "description"
-            <*> getM "notBefore" (textToTime <$>)
-            <*> getM "notAfter" (textToTime <$>)
+            <*> getT "notBefore"
+            <*> getT "notAfter"
             )
         <*> instanceStateSink "instanceState"
         <*> instanceStatusTypeSink "systemStatus"
@@ -214,12 +224,12 @@
     => Text -> GLSink Event m InstanceStatusType
 instanceStatusTypeSink name = element name $
     InstanceStatusType
-    <$> getF "status" instanceStatusTypeStatus'
+    <$> getT "status"
     <*> itemsSet "details" (
         InstanceStatusDetail
         <$> getT "name"
         <*> getT "status"
-        <*> getM "impairedSince" (textToTime <$>)
+        <*> getT "impairedSince"
         )
 
 ------------------------------------------------------------
@@ -266,7 +276,7 @@
     => [Text] -- ^ InstanceIds
     -> EC2 m Bool
 rebootInstances instanceIds =
-    ec2Query "RebootInstances" params returnBool
+    ec2Query "RebootInstances" params $ getT "return"
   where
     params = [ArrayParams "InstanceId" instanceIds]
 
@@ -306,7 +316,9 @@
             $ runInstancesRequestSecurityGroups param
         , blockDeviceMappingParams
             $ runInstancesRequestBlockDeviceMappings param
-        ] ++ maybeParams
+        ] ++ networkInterfaceParams
+             (runInstancesRequestNetworkInterfaces param)
+          ++ maybeParams
             [ ("KeyName", runInstancesRequestKeyName param)
             , ("UserData"
               , bsToText <$> runInstancesRequestUserData param
@@ -339,7 +351,8 @@
                 <$> runInstancesRequestShutdownBehavior param
               )
             , ("PrivateIpAddress"
-              , runInstancesRequestPrivateIpAddress param
+              , toText
+                <$> runInstancesRequestPrivateIpAddress param
               )
             , ("ClientToken", runInstancesRequestClientToken param)
             , ("IamInstanceProfile.Arn"
@@ -388,6 +401,42 @@
         Nothing
         Nothing
 
+networkInterfaceParams :: [NetworkInterfaceParam] -> [QueryParam]
+networkInterfaceParams nips = f 1 nips
+  where
+    f :: Int -> [NetworkInterfaceParam] -> [QueryParam]
+    f _ [] = []
+    f n (ni:nis) = g n ni ++ f (n + 1) nis
+    g n (NetworkInterfaceParamAttach nid idx dot) =
+        [ ValueParam (p n "NetworkInterfaceId") nid
+        , ValueParam (p n "DeviceIndex") $ toText idx
+        , ValueParam (p n "DeleteOnTermination") $ boolToText dot
+        ]
+    g n (NetworkInterfaceParamCreate idx sn desc pip sip sec dot) =
+        [ ValueParam (p n "DeviceIndex") $ toText idx
+        , ValueParam (p n "SubnetId") sn
+        , ValueParam (p n "Description") desc
+        , ArrayParams (p n "SecurityroupId") sec
+        , ValueParam (p n "DeleteOnTermination") $ boolToText dot
+        ] ++ maybeParams [(p n "PrivateIpAddress", toText <$> pip)]
+          ++ s n sip
+    p n name = "NetworkInterface." <> toText n <> "." <> name
+    s _ SecondaryPrivateIpAddressParamNothing = []
+    s n (SecondaryPrivateIpAddressParamCount c) =
+        [ ValueParam
+          (p n "SecondaryPrivateIpAddressCount")
+          $ toText c
+        ]
+    s n (SecondaryPrivateIpAddressParamSpecified addrs pr) =
+        [ privateIpAddressesParam (p n "PrivateIpAddresses") addrs
+        ] ++ maybe
+            []
+            (\i -> [
+              ValueParam
+              (p n "PrivateIpAddresses." <> toText i <> ".Primary")
+              "true"])
+            pr
+
 sbToText :: ShutdownBehavior -> Text
 sbToText ShutdownBehaviorStop      = "stop"
 sbToText ShutdownBehaviorTerminate = "terminate"
@@ -403,7 +452,7 @@
     ec2Query "GetConsoleOutput" [ValueParam "InstanceId" iid] $
         ConsoleOutput
         <$> getT "instanceId"
-        <*> getF "timestamp" textToTime
+        <*> getT "timestamp"
         <*> getT "output"
 
 ------------------------------------------------------------
@@ -417,7 +466,7 @@
     ec2Query "GetPasswordData" [ValueParam "InstanceId" iid] $
         PasswordData
         <$> getT "instanceId"
-        <*> getF "timestamp" textToTime
+        <*> getT "timestamp"
         <*> getT "passwordData"
 
 describeInstanceAttribute
@@ -427,7 +476,7 @@
     -> EC2 m InstanceAttribute
 describeInstanceAttribute iid attr =
     ec2Query "DescribeInstanceAttribute" params
-        $ getT "instanceId" *> f attr
+        $ getT_ "instanceId" *> f attr
   where
     str = iar attr
     params =
@@ -449,19 +498,21 @@
         , (InstanceAttributeRequestRamdiskId, InstanceAttributeRamdiskId)
         , (InstanceAttributeRequestUserData, InstanceAttributeUserData)
         , (InstanceAttributeRequestDisableApiTermination,
-           InstanceAttributeDisableApiTermination
-           . textToBool . fromJust)
+           InstanceAttributeDisableApiTermination . just)
         , (InstanceAttributeRequestShutdownBehavior,
            InstanceAttributeShutdownBehavior
-           . shutdownBehavior . fromJust)
-        , (InstanceAttributeRequestRootDeviceName, InstanceAttributeRootDeviceName)
+           . fromJust . fromTextMay . fromJust)
+        , (InstanceAttributeRequestRootDeviceName,
+           InstanceAttributeRootDeviceName)
         , (InstanceAttributeRequestSourceDestCheck,
-           InstanceAttributeSourceDestCheck . (textToBool <$>))
+           InstanceAttributeSourceDestCheck
+           . fromTextMay . fromJust)
         , (InstanceAttributeRequestEbsOptimized,
-           InstanceAttributeEbsOptimized . textToBool . fromJust)
+           InstanceAttributeEbsOptimized . just)
         ]
+    just = fromJust . join . (fromTextMay <$>)
     valueSink name val =
-        (element name $ getMT "value") >>= return . val
+        (element name $ getT "value") >>= return . val
 
 iar :: InstanceAttributeRequest -> Text
 iar InstanceAttributeRequestInstanceType          = "instanceType"
@@ -488,7 +539,7 @@
     -> ResetInstanceAttributeRequest
     -> EC2 m Bool
 resetInstanceAttribute iid attr =
-    ec2Query "ResetInstanceAttribute" params returnBool
+    ec2Query "ResetInstanceAttribute" params $ getT "return"
   where
     params =
         [ ValueParam "InstanceId" iid
@@ -502,7 +553,7 @@
     -> [ModifyInstanceAttributeRequest]
     -> EC2 m Bool
 modifyInstanceAttribute iid attrs =
-    ec2Query "ModifyInstanceAttribute" params returnBool
+    ec2Query "ModifyInstanceAttribute" params $ getT "return"
   where
     params = ValueParam "InstanceId" iid:concatMap miap attrs
 
diff --git a/AWS/EC2/Internal.hs b/AWS/EC2/Internal.hs
--- a/AWS/EC2/Internal.hs
+++ b/AWS/EC2/Internal.hs
@@ -1,9 +1,22 @@
 {-# LANGUAGE RankNTypes #-}
+{-# LANGUAGE ScopedTypeVariables #-}
 
 module AWS.EC2.Internal
-    where
+    ( module AWS.Class
+    , EC2
+    , initialEC2Context
+    , runEC2
+    , itemConduit
+    , itemsSet
+    , resourceTagSink
+    , productCodeSink
+    , stateReasonSink
+    , volumeTypeSink
+    , groupSetSink
+    ) where
 
 import Control.Monad.IO.Class (MonadIO)
+import Control.Monad.Trans.Class (lift)
 import qualified Network.HTTP.Conduit as HTTP
 import Data.ByteString.Char8 ()
 import Control.Applicative
@@ -13,9 +26,7 @@
 import Data.Text (Text)
 
 import AWS.Class
-import AWS.EC2.Convert
 import AWS.Credential
-import AWS.Util
 import AWS.Lib.Parser
 import AWS.EC2.Types
 
@@ -49,14 +60,14 @@
 resourceTagSink = itemsSet "tagSet" $
     ResourceTag
     <$> getT "key"
-    <*> getMT "value"
+    <*> getT "value"
 
 productCodeSink :: MonadThrow m
     => GLSink Event m [ProductCode]
 productCodeSink = itemsSet "productCodes" $
     ProductCode
     <$> getT "productCode"
-    <*> getF "type" productCodeType'
+    <*> getT "type"
 
 stateReasonSink :: MonadThrow m
     => GLSink Event m (Maybe StateReason)
@@ -65,11 +76,16 @@
     <$> getT "code"
     <*> getT "message"
 
+volumeType :: MonadThrow m => Text -> Maybe Int -> m VolumeType
+volumeType t Nothing  | t == "standard" = return $ VolumeTypeStandard
+volumeType t (Just i) | t == "io1"      = return $ VolumeTypeIO1 i
+volumeType t _ = monadThrow $ TextConversionException t
+
 volumeTypeSink :: MonadThrow m
-    => GLSink Event m VolumeType
-volumeTypeSink = volumeType
-    <$> getT "volumeType"
-    <*> getM "iops" (textToInt <$>)
+    => Pipe Event Event o u m VolumeType
+volumeTypeSink = volumeType <$> getT "volumeType" <*> getT "iops" >>= lift
 
-returnBool :: MonadThrow m => GLSink Event m Bool
-returnBool = getF "return" textToBool
+groupSetSink :: MonadThrow m => GLSink Event m [Group]
+groupSetSink = itemsSet "groupSet" $ Group
+    <$> getT "groupId"
+    <*> getT "groupName"
diff --git a/AWS/EC2/NetworkInterface.hs b/AWS/EC2/NetworkInterface.hs
new file mode 100644
--- /dev/null
+++ b/AWS/EC2/NetworkInterface.hs
@@ -0,0 +1,111 @@
+{-# LANGUAGE FlexibleContexts, RankNTypes #-}
+
+module AWS.EC2.NetworkInterface
+    ( assignPrivateIpAddresses
+    , unassignPrivateIpAddresses
+    , describeNetworkInterfaces
+    ) where
+
+import Data.IP (IPv4)
+import Data.Text (Text)
+import Data.XML.Types (Event)
+import Data.Conduit
+import Control.Monad.Trans.Control (MonadBaseControl)
+import Control.Applicative
+
+import AWS.EC2.Internal
+import AWS.EC2.Types
+import AWS.EC2.Params
+import AWS.EC2.Query
+import AWS.Lib.Parser
+import AWS.Util
+
+assignPrivateIpAddresses
+    :: (MonadBaseControl IO m, MonadResource m)
+    => Text -- ^ NetworkInterfaceId
+    -> Either [IPv4] Int -- ^ PrivateIpAddresses or Count
+    -> Maybe Bool
+    -> EC2 m Bool
+assignPrivateIpAddresses niid epip ar =
+    ec2Query "AssignPrivateIpAddresses" params $ getT "return"
+  where
+    params = [ValueParam "NetworkInterfaceId" niid]
+        ++ either f g epip
+        ++ maybeParams [("AllowReassignment", boolToText <$> ar)]
+    f addrs = [privateIpAddressesParam "PrivateIpAddress" addrs]
+    g cnt = [ValueParam "SecondaryPrivateIpAddressCount"
+        $ toText cnt]
+
+unassignPrivateIpAddresses
+    :: (MonadBaseControl IO m, MonadResource m)
+    => Text -- ^ NetworkInterfaceId
+    -> [IPv4] -- ^ PrivateIpAddresses
+    -> EC2 m Bool
+unassignPrivateIpAddresses niid addrs =
+    ec2Query "UnassignPrivateIpAddresses" params $ getT "return"
+  where
+    params =
+        [ ValueParam "NetworkInterfaceId" niid
+        , privateIpAddressesParam "PrivateIpAddress" addrs
+        ]
+
+describeNetworkInterfaces
+    :: (MonadBaseControl IO m, MonadResource m)
+    => [Text] -- ^ NetworkInterfaceIds
+    -> [Filter]
+    -> EC2 m (ResumableSource m NetworkInterface)
+describeNetworkInterfaces niid filters =
+    ec2QuerySource "DescribeNetworkInterfaces" params
+        $ itemConduit "networkInterfaceSet" networkInterfaceSink
+  where
+    params =
+        [ ArrayParams "NetworkInterfaceId" niid
+        , FilterParams filters
+        ]
+
+networkInterfaceSink
+    :: MonadThrow m
+    => GLSink Event m NetworkInterface
+networkInterfaceSink = NetworkInterface
+    <$> getT "networkInterfaceId"
+    <*> getT "subnetId"
+    <*> getT "vpcId"
+    <*> getT "availabilityZone"
+    <*> getT "description"
+    <*> getT "ownerId"
+    <*> getT "requesterId"
+    <*> getT "requesterManaged"
+    <*> getT "status"
+    <*> getT "macAddress"
+    <*> getT "privateIpAddress"
+    <*> getT "privateDnsName"
+    <*> getT "sourceDestCheck"
+    <*> groupSetSink
+    <*> elementM "attachment" (NetworkInterfaceAttachment
+        <$> getT "attachmentId"
+        <*> getT "instanceId"
+        <*> getT "instanceOwnerId"
+        <*> getT "deviceIndex"
+        <*> getT "status"
+        <*> getT "attachTime"
+        <*> getT "deleteOnTermination"
+        )
+    <*> networkInterfaceAssociationSink
+    <*> resourceTagSink
+    <*> itemsSet "privateIpAddressesSet" (
+        NetworkInterfacePrivateIpAddress
+        <$> getT "privateIpAddress"
+        <*> getT "primary"
+        <*> networkInterfaceAssociationSink
+        )
+
+networkInterfaceAssociationSink
+    :: MonadThrow m
+    => GLSink Event m (Maybe NetworkInterfaceAssociation)
+networkInterfaceAssociationSink =
+    elementM "association" $ NetworkInterfaceAssociation
+        <$> getT "attachmentId"
+        <*> getT "instanceId"
+        <*> getT "publicIp"
+        <*> getT "ipOwnerId"
+        <*> getT "associationId"
diff --git a/AWS/EC2/Params.hs b/AWS/EC2/Params.hs
--- a/AWS/EC2/Params.hs
+++ b/AWS/EC2/Params.hs
@@ -1,7 +1,9 @@
 module AWS.EC2.Params where
 
 import Control.Applicative
+import Data.Text (Text)
 import qualified Data.Text as T
+import Data.IP (IPv4)
 
 import AWS.EC2.Query (QueryParam(..))
 import AWS.EC2.Types
@@ -37,3 +39,9 @@
         [ ("Ebs.VolumeType", "io1")
         , ("Ebs.Iops", T.pack $ show iops)
         ]
+
+privateIpAddressesParam :: Text -> [IPv4] -> QueryParam
+privateIpAddressesParam name addrs = StructArrayParams
+    name
+    $ unconcat $ zip (repeat "PrivateIpAddress")
+    $ map toText addrs
diff --git a/AWS/EC2/Query.hs b/AWS/EC2/Query.hs
--- a/AWS/EC2/Query.hs
+++ b/AWS/EC2/Query.hs
@@ -36,6 +36,7 @@
 
 #ifdef DEBUG
 import Debug.Trace
+import Control.Monad.IO.Class (liftIO)
 import qualified Data.Conduit.Binary as CB
 #endif
 
@@ -49,14 +50,14 @@
     await -- EventBeginElement DescribeImagesResponse
     getT "requestId"
 
-sinkError :: MonadThrow m => Int -> GLSink Event m a
-sinkError s = do
+sinkError :: MonadThrow m => ByteString -> Int -> GLSink Event m a
+sinkError a s = do
     await
     element "Response" $ do
         (c,m) <- element "Errors" $ element "Error" $
             (,) <$> getT "Code" <*> getT "Message"
         r <- getT "RequestID"
-        lift $ monadThrow $ ClientError s c m r
+        lift $ monadThrow $ ClientError a s c m r
 
 ec2Query
     :: (MonadResource m, MonadBaseControl IO m)
@@ -106,18 +107,19 @@
         (\t -> ValueParam "NextToken" t:params) token
 
 nextToken :: MonadThrow m => Conduit Event m o
-nextToken = getMT "nextToken" >>= maybe (return ()) (E.throw . NextToken)
+nextToken = getT "nextToken" >>= maybe (return ()) (E.throw . NextToken)
 
 #ifdef DEBUG
 ec2QueryDebug
     :: (MonadResource m, MonadBaseControl IO m)
     => ByteString
     -> [QueryParam]
-    -> EC2 m (Source m o)
+    -> EC2 m a
 ec2QueryDebug action params = do
     cred <- Reader.ask
     ctx <- State.get
     lift $ do
+        liftIO $ mapM_ print params
         response <- requestQuery cred ctx action params apiVersion sinkError
         (res, _) <- unwrapResumable response
         res $$ CB.sinkFile "debug.txt" >>= fail "debug"
@@ -130,4 +132,4 @@
     -> Text -- ^ ID of Target
     -> EC2 m Bool
 ec2Delete apiName idName targetId = do
-    ec2Query apiName [ ValueParam idName targetId ] returnBool
+    ec2Query apiName [ ValueParam idName targetId ] $ getT "return"
diff --git a/AWS/EC2/RouteTable.hs b/AWS/EC2/RouteTable.hs
--- a/AWS/EC2/RouteTable.hs
+++ b/AWS/EC2/RouteTable.hs
@@ -15,12 +15,10 @@
 import Control.Monad.Trans.Control (MonadBaseControl)
 import Control.Applicative
 
-import AWS.EC2.Convert
 import AWS.EC2.Internal
 import AWS.EC2.Types
 import AWS.EC2.Query
 import AWS.Lib.Parser
-import AWS.Util
 
 ------------------------------------------------------------
 -- describeRouteTables
@@ -46,27 +44,27 @@
     <*> getT "vpcId"
     <*> routeSink
     <*> routeTableAssociationSink
-    <*> getMT "propagatingVgwSet"
+    <*> getT "propagatingVgwSet"
     <*> resourceTagSink
 
 routeSink :: MonadThrow m
     => GLSink Event m [Route]
 routeSink = itemsSet "routeSet" $ Route
     <$> getT "destinationCidrBlock"
-    <*> getMT "gatewayId"
-    <*> getMT "instanceId"
-    <*> getMT "instanceOwnerId"
-    <*> getMT "networkInterfaceId"
-    <*> getF "state" routeState'
-    <*> getM "origin" (routeOrigin' <$>)
+    <*> getT "gatewayId"
+    <*> getT "instanceId"
+    <*> getT "instanceOwnerId"
+    <*> getT "networkInterfaceId"
+    <*> getT "state"
+    <*> getT "origin"
 
 routeTableAssociationSink :: MonadThrow m
     => GLSink Event m [RouteTableAssociation]
 routeTableAssociationSink = itemsSet "associationSet" $ RouteTableAssociation
     <$> getT "routeTableAssociationId"
     <*> getT "routeTableId"
-    <*> getMT "subnetId"
-    <*> getM "main" (textToBool <$>)
+    <*> getT "subnetId"
+    <*> getT "main"
 
 ------------------------------------------------------------
 -- createRouteTable
@@ -112,8 +110,9 @@
     => Text -- ^ AssociationId
     -> EC2 m Bool -- ^ return
 disassociateRouteTable aid =
-   ec2Query "DisassociateRouteTable" [ValueParam "AssociationId" aid]
-        $ getF "return" textToBool
+    ec2Query "DisassociateRouteTable"
+        [ValueParam "AssociationId" aid]
+            $ getT "return"
 
 ------------------------------------------------------------
 -- replaceRouteTableAssociation
diff --git a/AWS/EC2/SecurityGroup.hs b/AWS/EC2/SecurityGroup.hs
--- a/AWS/EC2/SecurityGroup.hs
+++ b/AWS/EC2/SecurityGroup.hs
@@ -39,7 +39,7 @@
         <*> getT "groupId"
         <*> getT "groupName"
         <*> getT "groupDescription"
-        <*> getMT "vpcId"
+        <*> getT "vpcId"
         <*> ipPermissionsSink "ipPermissions"
         <*> ipPermissionsSink "ipPermissionsEgress"
         <*> resourceTagSink
@@ -53,15 +53,16 @@
 ipPermissionsSink :: MonadThrow m
     => Text -> GLSink Event m [IpPermission]
 ipPermissionsSink name = itemsSet name $ IpPermission
-    <$> getT "ipProtocol" <*> getM "fromPort" (textToInt <$>)
-    <*> getM "toPort" (textToInt <$>)
+    <$> getT "ipProtocol"
+    <*> getT "fromPort"
+    <*> getT "toPort"
     <*> itemsSet "groups" (
         UserIdGroupPair
-        <$> getMT "userId"
+        <$> getT "userId"
         <*> getT "groupId"
-        <*> getMT "groupName"
+        <*> getT "groupName"
         )
-    <*> itemsSet "ipRanges" (IpRange <$> getT "cidrIp")
+    <*> itemsSet "ipRanges" (getT "cidrIp")
 
 createSecurityGroup
     :: (MonadResource m, MonadBaseControl IO m)
@@ -71,7 +72,7 @@
     -> EC2 m (Maybe Text) -- ^ GroupId
 createSecurityGroup name desc vpc =
     ec2Query "CreateSecurityGroup" params
-        $ getT "return" *> getMT "groupId"
+        $ getT_ "return" *> getT "groupId"
   where
     params =
         [ ValueParam "GroupName" name
@@ -83,8 +84,7 @@
     => SecurityGroupRequest
     -> EC2 m Bool
 deleteSecurityGroup param =
-    ec2Query "DeleteSecurityGroup" [p param]
-        $ getF "return" textToBool
+    ec2Query "DeleteSecurityGroup" [p param] $ getT "return"
 
 p :: SecurityGroupRequest -> QueryParam
 p (SecurityGroupRequestGroupId t)   = ValueParam "GroupId" t
@@ -135,7 +135,7 @@
     -> [IpPermission]
     -> EC2 m Bool
 securityGroupQuery act param ipps =
-    ec2Query act params $ getF "return" textToBool
+    ec2Query act params $ getT "return"
   where
     params = [p param]
         ++ concatMap (uncurry ipPermissionParam) (zip intstr ipps)
@@ -170,4 +170,4 @@
             ])
     ipr n r = ValueParam
         (pre <> ".IPRanges." <> toText n <> ".CidrIp")
-        $ ipRangeCidrIp r
+        $ toText r
diff --git a/AWS/EC2/Snapshot.hs b/AWS/EC2/Snapshot.hs
--- a/AWS/EC2/Snapshot.hs
+++ b/AWS/EC2/Snapshot.hs
@@ -17,8 +17,6 @@
 import AWS.EC2.Types
 import AWS.EC2.Query
 import AWS.Lib.Parser
-import AWS.Util
-import AWS.EC2.Convert
 
 describeSnapshots
     :: (MonadResource m, MonadBaseControl IO m)
@@ -43,18 +41,18 @@
 snapshotSink = Snapshot
         <$> getT "snapshotId"
         <*> getT "volumeId"
-        <*> getF "status" snapshotStatus'
-        <*> getF "startTime" textToTime
+        <*> getT "status"
+        <*> getT "startTime"
         <*> getT "progress"
         <*> getT "ownerId"
-        <*> getF "volumeSize" textToInt
+        <*> getT "volumeSize"
         <*> getT "description"
-        <*> getMT "ownerAlias"
+        <*> getT "ownerAlias"
         <*> resourceTagSink
 
 createSnapshot
     :: (MonadResource m, MonadBaseControl IO m)
-    => Text -- ^ SnapshotId
+    => Text -- ^ VolumeId
     -> Maybe Text -- ^ Description
     -> EC2 m Snapshot
 createSnapshot volid desc =
@@ -68,6 +66,6 @@
     => Text -- ^ SnapshotId
     -> EC2 m Bool
 deleteSnapshot ssid =
-    ec2Query "DeleteSnapshot" params $ getF "return" textToBool
+    ec2Query "DeleteSnapshot" params $ getT "return"
   where
     params = [ValueParam "SnapshotId" ssid]
diff --git a/AWS/EC2/Subnets.hs b/AWS/EC2/Subnets.hs
--- a/AWS/EC2/Subnets.hs
+++ b/AWS/EC2/Subnets.hs
@@ -12,7 +12,6 @@
 import Control.Monad.Trans.Control (MonadBaseControl)
 import Control.Applicative
 
-import AWS.EC2.Convert
 import AWS.EC2.Internal
 import AWS.EC2.Types
 import AWS.EC2.Query
@@ -40,10 +39,10 @@
     => GLSink Event m Subnet
 subnetSink = Subnet
     <$> getT "subnetId"
-    <*> getF "state" subnetState'
+    <*> getT "state"
     <*> getT "vpcId"
     <*> getT "cidrBlock"
-    <*> getF "availableIpAddressCount" textToInt
+    <*> getT "availableIpAddressCount"
     <*> getT "availabilityZone"
     <*> resourceTagSink
 
@@ -63,7 +62,7 @@
 createSubnetParam :: CreateSubnetRequest -> [QueryParam]
 createSubnetParam (CreateSubnetRequest vid cidr zone) =
     [ ValueParam "VpcId" vid
-    , ValueParam "CidrBlock" cidr
+    , ValueParam "CidrBlock" $ toText cidr
     ] ++ maybe [] (\a -> [ValueParam "AvailabilityZone" a]) zone
 
 ------------------------------------------------------------
diff --git a/AWS/EC2/Tag.hs b/AWS/EC2/Tag.hs
--- a/AWS/EC2/Tag.hs
+++ b/AWS/EC2/Tag.hs
@@ -28,7 +28,7 @@
         <$> getT "resourceId"
         <*> getT "resourceType"
         <*> getT "key"
-        <*> getMT "value"
+        <*> getT "value"
   where
     params = [FilterParams filters]
 
@@ -38,7 +38,7 @@
     -> [(Text, Text)] -- ^ (Key, Value)
     -> EC2 m Bool
 createTags rids kvs =
-    ec2Query "CreateTags" params returnBool
+    ec2Query "CreateTags" params $ getT "return"
   where
     params =
         [ ArrayParams "ResourceId" rids ]
@@ -54,7 +54,7 @@
     -> [ResourceTag]
     -> EC2 m Bool
 deleteTags rids tags =
-    ec2Query "DeleteTags" params returnBool
+    ec2Query "DeleteTags" params $ getT "return"
   where
     params =
         [ ArrayParams "ResourceId" rids ]
diff --git a/AWS/EC2/Types.hs b/AWS/EC2/Types.hs
--- a/AWS/EC2/Types.hs
+++ b/AWS/EC2/Types.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE TemplateHaskell #-}
 module AWS.EC2.Types
     ( Address(..)
     , AddressDomain(..)
@@ -25,6 +26,7 @@
     , EbsInstanceBlockDevice(..)
     , EbsSource(..)
     , EC2Return(..)
+    , Filter
     , Group(..)
     , Hypervisor(..)
     , IamInstanceProfile(..)
@@ -39,6 +41,8 @@
     , InstanceLifecycle(..)
     , InstanceMonitoringState(..)
     , InstanceNetworkInterface(..)
+    , InstanceNetworkInterfaceAssociation(..)
+    , InstanceNetworkInterfaceAttachment(..)
     , InstancePrivateIpAddress(..)
     , InstanceState(..)
     , InstanceStateChange(..)
@@ -51,7 +55,6 @@
     , InstanceStatusDetailName
     , InstanceStatusDetailStatus
     , IpPermission(..)
-    , IpRange(..)
     , KeyPair(..)
     , ModifyInstanceAttributeRequest(..)
     , LaunchPermissionItem(..)
@@ -60,9 +63,12 @@
     , NetworkAclEntry(..)
     , NetworkAclEntryRequest(..)
     , NetworkAclRuleAction(..)
+    , NetworkInterface(..)
     , NetworkInterfaceAssociation(..)
     , NetworkInterfaceAttachment(..)
     , NetworkInterfaceParam(..)
+    , NetworkInterfacePrivateIpAddress(..)
+    , NetworkInterfaceStatus(..)
     , PasswordData(..)
     , Placement(..)
     , Platform(..)
@@ -82,6 +88,7 @@
     , RouteState(..)
     , RouteOrigin(..)
     , RunInstancesRequest(..)
+    , SecondaryPrivateIpAddressParam(..)
     , SecurityGroup(..)
     , SecurityGroupRequest(..)
     , ShutdownBehavior(..)
@@ -121,10 +128,14 @@
     , InternetGatewayAttachmentState(..)
     ) where
 
+import Data.IP (IPv4, AddrRange)
 import Data.Text (Text)
 import Data.ByteString (ByteString)
 import Data.Time (UTCTime)
 
+import AWS.Class
+import AWS.Lib.FromText
+
 data Image = Image
     { imageId :: Text
     , imageLocation :: Text
@@ -140,8 +151,8 @@
     , imageStateReason :: Maybe StateReason
     , imageViridianEnabled :: Maybe Bool
     , imageOwnerAlias :: Maybe Text
-    , imageName :: Text
-    , imageDescription :: Text
+    , imageName :: Maybe Text
+    , imageDescription :: Maybe Text
     , imageBillingProducts :: [Text]
     , imageRootDeviceType :: RootDeviceType
     , imageRootDeviceName :: Maybe Text
@@ -150,7 +161,7 @@
     , imageTagSet :: [ResourceTag]
     , imageHypervisor :: Hypervisor
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data AMIAttribute
     = AMIDescription
@@ -159,7 +170,7 @@
     | AMILaunchPermission
     | AMIProductCodes
     | AMIBlockDeviceMapping
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data AMIAttributeDescription = AMIAttributeDescription
     { amiAttributeDescriptionImageId :: Text
@@ -170,64 +181,64 @@
     , amiAttributeDescriptionDescription :: Maybe Text
     , amiAttributeDescriptionBlockDeviceMapping :: [BlockDeviceMapping]
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data LaunchPermissionItem = LaunchPermissionItem
     { launchPermissionItemGroup :: Text
     , launchPermissionUserId :: Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data ImageState
     = ImageStateAvailable
     | ImageStatePending
     | ImageStateFailed
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data ProductCode = ProductCode
     { productCodeCode :: Text
     , productCodeType :: ProductCodeType
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data ProductCodeItem = ProductCodeItem
     { productCodeItemProductCode :: Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data ProductCodeType
     = ProductCodeDevpay
     | ProductCodeMarketplace
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data ImageType
     = ImageTypeMachine
     | ImageTypeKernel
     | ImageTypeRamDisk
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data Platform
     = PlatformWindows
     | PlatformOther
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data StateReason = StateReason
     { stateReasonCode :: Text
     , stateReasonMessage :: Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data RootDeviceType
     = RootDeviceTypeEBS
     | RootDeviceTypeInstanceStore
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data BlockDeviceMapping = BlockDeviceMapping
     { blockDeviceMappingDeviceName :: Text
     , blockDeviceMappingVirtualName :: Maybe Text
     , blockDeviceMappingEbs :: Maybe EbsBlockDevice
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data EbsBlockDevice = EbsBlockDevice
     { ebsSnapshotId :: Maybe Text
@@ -235,34 +246,34 @@
     , ebsDeleteOnTermination :: Bool
     , ebsVolumeType :: VolumeType
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VolumeType
     = VolumeTypeStandard
     | VolumeTypeIO1 Int
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VirtualizationType
     = VirtualizationTypeParavirtual
     | VirtualizationTypeHVM
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data ResourceTag = ResourceTag
     { resourceTagKey :: Text
     , resourceTagValue :: Maybe Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data Hypervisor
     = HypervisorOVM
     | HypervisorXen
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data Region = Region
     { regionName :: Text
     , regionEndpoint :: Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data AvailabilityZone = AvailabilityZone
     { zoneName :: Text
@@ -270,7 +281,7 @@
     , zoneRegionName :: Text
     , zoneMessageSet :: [AvailabilityZoneMessage]
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 type AvailabilityZoneMessage = Text
 
@@ -281,7 +292,7 @@
     , reservationInstanceSet :: [Instance]
     , reservationRequesterId :: Maybe Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data Instance = Instance
     { instanceId :: Text
@@ -302,8 +313,8 @@
     , instanceMonitoring :: InstanceMonitoringState
     , instanceSubnetId :: Maybe Text
     , instanceVpcId :: Maybe Text
-    , instancePrivateIpAddress :: Maybe Text
-    , instanceIpAddress :: Maybe Text
+    , instancePrivateIpAddress :: Maybe IPv4
+    , instanceIpAddress :: Maybe IPv4
     , instanceSourceDestCheck :: Maybe Bool
     , instancevpcGroupSet :: [Group]
     , instanceStateReason :: Maybe StateReason
@@ -321,7 +332,7 @@
     , instanceIamInstanceProfile :: Maybe IamInstanceProfile
     , instanceEbsOptimized :: Bool -- default: false
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data InstanceStatus = InstanceStatus
     { instanceStatusInstanceId :: Text
@@ -331,7 +342,7 @@
     , instanceStatusSystemStatus :: InstanceStatusType
     , instanceStatusInstanceStatus :: InstanceStatusType
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data InstanceStatusEvent = InstanceStatusEvent
     { instanceStatusEventCode :: InstanceStatusEventCode
@@ -339,34 +350,34 @@
     , instanceStatusEventNotBefore :: Maybe UTCTime
     , instanceStatusEventNotAfter :: Maybe UTCTime
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data InstanceStatusEventCode
     = InstanceStatusEventCodeInstanceReboot
     | InstanceStatusEventCodeInstanceStop
     | InstanceStatusEventCodeSystemReboot
     | InstanceStatusEventCodeInstanceRetirement
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data InstanceStatusType = InstanceStatusType
     { instanceStatusTypeStatus :: InstanceStatusTypeStatus
     , instanceStatusTypeDetails :: [InstanceStatusDetail]
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data InstanceStatusTypeStatus
     = InstanceStatusTypeStatusOK
     | InstanceStatusTypeStatusImpaired
     | InstanceStatusTypeStatusInsufficientData
     | InstanceStatusTypeStatusNotApplicable
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data InstanceStatusDetail = InstanceStatusDetail
     { instanceStatusDetailName :: InstanceStatusDetailName
     , instanceStatusDetailStatus :: InstanceStatusDetailStatus
     , instanceStatusDetailImpairedSince :: Maybe UTCTime
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 type InstanceStatusDetailName = Text
 
@@ -376,7 +387,7 @@
     { groupId :: Text
     , groupName :: Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data InstanceState
     = InstanceStatePending
@@ -386,28 +397,28 @@
     | InstanceStateStopping
     | InstanceStateStopped
     | InstanceStateUnknown Int
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data Placement = Placement
     { placementAvailabilityZone :: Text
     , placementGroupName :: Text
     , placementTenancy :: Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data InstanceMonitoringState
     = MonitoringDisabled
     | MonitoringEnabled
     | MonitoringPending
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
-data Architecture = I386 | X86_64 deriving (Show, Eq)
+data Architecture = I386 | X86_64 deriving (Show, Read, Eq)
 
 data InstanceBlockDeviceMapping = InstanceBlockDeviceMapping
     { instanceBlockDeviceMappingDeviceName :: Text
     , instanceBlockDeviceMappingEbs :: EbsInstanceBlockDevice
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data EbsInstanceBlockDevice = EbsInstanceBlockDevice
     { ebsInstanceBlockDeviceVolumeId :: Text
@@ -415,65 +426,68 @@
     , ebsInstanceBlockDeviceAttachTime :: UTCTime
     , ebsInstanceBlockDeviceDeleteOnTermination :: Bool
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data InstanceLifecycle
     = LifecycleSpot
     | LifecycleNone
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data InstanceNetworkInterface = InstanceNetworkInterface
     { instanceNetworkInterfaceId :: Text
     , instanceNetworkInterfaceSubnetId :: Text
     , instanceNetworkInterfaceVpcId :: Text
-    , instanceNetworkInterfaceDescription :: Text
+    , instanceNetworkInterfaceDescription :: Maybe Text
     , instanceNetworkInterfaceOwnerId :: Text
     , instanceNetworkInterfaceStatus :: Text
-    , instanceNetworkInterfacePrivateIpAddress :: Text
+    , instanceNetworkInterfacePrivateIpAddress :: IPv4
     , instanceNetworkInterfacePrivateDnsName :: Maybe Text
     , instanceNetworkInterfaceSourceDestCheck :: Bool
     , instanceNetworkInterfaceGroupSet :: [Group]
     , instanceNetworkInterfaceAttachment
-        :: NetworkInterfaceAttachment
+        :: InstanceNetworkInterfaceAttachment
     , instanceNetworkInterfaceAssociation
-        :: Maybe NetworkInterfaceAssociation
-    , instanceNetworkInterfacePrivateIpAddressSet
+        :: Maybe InstanceNetworkInterfaceAssociation
+    , instanceNetworkInterfacePrivateIpAddressesSet
         :: [InstancePrivateIpAddress]
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
-data NetworkInterfaceAttachment = NetworkInterfaceAttachment
-    { networkInterfaceAttachmentId :: Text
-    , networkInterfaceAttachmentDeviceIndex :: Int
-    , networkInterfaceAttachmentStatus :: Text
-    , networkInterfaceAttachmentAttachTime :: UTCTime
-    , networkInterfaceAttachmentDeleteOnTermination :: Bool
+data InstanceNetworkInterfaceAttachment = InstanceNetworkInterfaceAttachment
+    { instanceNetworkInterfaceAttachmentId :: Text
+    , instanceNetworkInterfaceAttachmentDeviceIndex :: Int
+    , instanceNetworkInterfaceAttachmentStatus :: Text
+    , instanceNetworkInterfaceAttachmentAttachTime :: UTCTime
+    , instanceNetworkInterfaceAttachmentDeleteOnTermination
+        :: Bool
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
-data NetworkInterfaceAssociation = NetworkInterfaceAssociation
-    { networkInterfaceAssociationPublicIp :: Text
-    , networkInterfaceAssociationIpOwnerId :: Text
+data InstanceNetworkInterfaceAssociation
+    = InstanceNetworkInterfaceAssociation
+    { instanceNetworkInterfaceAssociationPublicIp :: Text
+    , instanceNetworkInterfaceAssociationIpOwnerId :: Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data InstancePrivateIpAddress = InstancePrivateIpAddress
-    { instancePrivateIpAddressAddress :: Text
+    { instancePrivateIpAddressAddress :: IPv4
     , instancePrivateIpAddressPrimary :: Bool
-    , instancePrivateIpAddressAssociation :: Maybe NetworkInterfaceAssociation
+    , instancePrivateIpAddressAssociation
+        :: Maybe InstanceNetworkInterfaceAssociation
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data IamInstanceProfile = IamInstanceProfile
     { iamInstanceProfileArn :: Text
     , iamInstanceProfileId :: Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data ShutdownBehavior
     = ShutdownBehaviorStop
     | ShutdownBehaviorTerminate
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data InstanceAttribute
     = InstanceAttributeInstanceType Text
@@ -488,32 +502,32 @@
     | InstanceAttributeGroupSet [Text]
     | InstanceAttributeProductCodes [ProductCode]
     | InstanceAttributeEbsOptimized Bool
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data Address = Address
-    { addressPublicIp :: Text
+    { addressPublicIp :: IPv4
     , addressAllocationId :: Maybe Text
     , addressDomain :: AddressDomain
     , addressInstanceId :: Maybe Text
     , addressAssociationId :: Maybe Text
     , addressNetworkInterfaceId :: Maybe Text
     , addressNetworkInterfaceOwnerId :: Maybe Text
-    , addressPrivateIpAddress :: Maybe Text
+    , addressPrivateIpAddress :: Maybe IPv4
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data AddressDomain = AddressDomainStandard | AddressDomainVPC
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data AllocateAddress = AllocateAddress
-    { allocateAddressPublicIp :: Text
+    { allocateAddressPublicIp :: IPv4
     , allocateAddressDomain :: AddressDomain
     , allocateAddressAllocationId :: Maybe Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data EC2Return = EC2Success | EC2Error Text
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data Tag = Tag
     { tagResourceId :: Text
@@ -521,14 +535,14 @@
     , tagKey :: Text
     , tagValue :: Maybe Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data InstanceStateChange = InstanceStateChange
     { instanceStateChangeInstanceId :: Text
     , instanceStateChangeCurrentState :: InstanceState
     , instanceStateChangePreviousState :: InstanceState
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data ConsoleOutput = ConsoleOutput
     { consoleOutputInstanceId :: Text
@@ -536,7 +550,7 @@
         -- ^ The time the data was last updated.
     , consoleOutputOutput :: Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data PasswordData = PasswordData
     { passwordDataInstanceId :: Text
@@ -544,7 +558,7 @@
       -- ^ The time the data was last updated.
     , passwordDataPasswordData :: Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data Snapshot = Snapshot
     { snapshotId :: Text
@@ -558,13 +572,13 @@
     , snapshotOwnerAlias :: Maybe Text
     , snapshotTagSet :: [ResourceTag]
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data SnapshotStatus
     = SnapshotPending
     | SnapshotCompleted
     | SnapshotError
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data Volume = Volume
     { volumeId :: Text
@@ -577,7 +591,7 @@
     , volumeTagSet :: [ResourceTag]
     , volumeVolumeType :: VolumeType
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VolumeState
     = VolumeStateCreating
@@ -586,7 +600,7 @@
     | VolumeStateDeleting
     | VolumeStateDeleted
     | VolumeStateError
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data AttachmentSetItemResponse = AttachmentSetItemResponse
     { attachmentSetItemResponseVolumeId :: Text
@@ -597,20 +611,20 @@
     , attachmentSetItemResponseAttachTime :: UTCTime
     , attachmentSetItemResponseDeleteOnTermination :: Maybe Bool
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data AttachmentSetItemResponseStatus
     = AttachmentSetItemResponseStatusAttaching
     | AttachmentSetItemResponseStatusAttached
     | AttachmentSetItemResponseStatusDetaching
     | AttachmentSetItemResponseStatusDetached
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data KeyPair = KeyPair
     { keyPairName :: Text
     , keyPairFingerprint :: Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data SecurityGroup = SecurityGroup
     { securityGroupOwnerId :: Text
@@ -622,28 +636,23 @@
     , securityGroupIpPermissionsEgress :: [IpPermission]
     , securityGroupTagSet :: [ResourceTag]
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data IpPermission = IpPermission
     { ipPermissionIpProtocol :: Text
     , ipPermissionFromPort :: Maybe Int
     , ipPermissionToPort :: Maybe Int
     , ipPermissionGroups :: [UserIdGroupPair]
-    , ipPermissionIpRanges :: [IpRange]
+    , ipPermissionIpRanges :: [AddrRange IPv4]
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data UserIdGroupPair = UserIdGroupPair
     { userIdGroupPairUserId :: Maybe Text
     , userIdGroupPairGroupId :: Text
     , userIdGroupPairGroupName :: Maybe Text
     }
-  deriving (Show, Eq)
-
-data IpRange = IpRange
-    { ipRangeCidrIp :: Text
-    }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data BlockDeviceMappingParam
     = BlockDeviceMappingParamEbs
@@ -661,24 +670,42 @@
         , blockDeviceMappingParamInstanceStoreVirtualName
             :: Maybe Text
         }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data EbsSource
     = EbsSourceSnapshotId Text
     | EbsSourceVolumeSize Int
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
-data NetworkInterfaceParam = NetworkInterfaceParam
-    { networkInterfaceParamInterfaceId :: Maybe Text
-    , networkInterfaceParamDeviceIndex :: Maybe Text
-    , networkInterfaceParamSubnetId :: Maybe Text
-    , networkInterfaceParamDescription :: Maybe Text
-    , networkInterfaceParamPrivateIpAddresses :: [Text]
-    , networkInterfaceParamSecurityGroupIds :: [Text]
-    , networkInterfaceParamDeleteOnTermination :: Maybe Bool
-    }
-  deriving (Show, Eq)
+data NetworkInterfaceParam
+    = NetworkInterfaceParamCreate
+        { networkInterfaceParamCreateDeviceIndex :: Int
+        , networkInterfaceParamCreateSubnetId :: Text
+        , networkInterfaceParamCreateDescription :: Text
+        , networkInterfaceParamCreatePrivateIpAddress
+            :: Maybe IPv4
+        , networkInterfaceParamCreatePrivateIpAddresses
+            :: SecondaryPrivateIpAddressParam
+        , networkInterfaceParamCreateSecurityGroupIds :: [Text]
+        , networkInterfaceParamCreateDeleteOnTermination :: Bool
+        }
+    | NetworkInterfaceParamAttach
+        { networkInterfaceParamAttachInterfaceId :: Text
+        , networkInterfaceParamAttachDeviceIndex :: Int
+        , networkInterfaceParamAttachDeleteOnTermination :: Bool
+        }
+  deriving (Show, Read, Eq)
 
+data SecondaryPrivateIpAddressParam
+    = SecondaryPrivateIpAddressParamNothing
+    | SecondaryPrivateIpAddressParamCount Int
+    | SecondaryPrivateIpAddressParamSpecified
+      { secondaryPrivateIpAddressParamSpecifiedAddresses :: [IPv4]
+      , secondaryPrivateIpAddressParamSpecifiedPrimary
+        :: Maybe Int
+      }
+  deriving (Show, Read, Eq)
+
 data VpnConnection = VpnConnection
     { vpnConnectionId :: Text
     , vpnConnectionState :: VpnConnectionState
@@ -691,50 +718,50 @@
     , vpnConnectionOptions :: Maybe VpnConnectionOptionsRequest
     , vpnConnectionRoutes :: Maybe VpnStaticRoute
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VpnConnectionState
     = VpnConnectionStatePending
     | VpnConnectionStateAvailable
     | VpnConnectionStateDeleting
     | VpnConnectionStateDeleted
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VpnTunnelTelemetry = VpnTunnelTelemetry
-    { vpnTunnelTelemetryOutsideIpAddress :: Text
+    { vpnTunnelTelemetryOutsideIpAddress :: IPv4
     , vpnTunnelTelemetryStatus :: VpnTunnelTelemetryStatus
     , vpnTunnelTelemetryLastStatusChange :: UTCTime
     , vpnTunnelTelemetryStatusMessage :: Text
     , vpnTunnelTelemetryAcceptRouteCount :: Int
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VpnTunnelTelemetryStatus
     = VpnTunnelTelemetryStatusUp
     | VpnTunnelTelemetryStatusDown
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VpnConnectionOptionsRequest = VpnConnectionOptionsRequest
     { vpnConnectionOptionsRequestStaticRoutesOnly :: Bool
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VpnStaticRoute = VpnStaticRoute
     { vpnStaticRouteDestinationCidrBlock :: Text
     , vpnStaticRouteSource :: VpnStaticRouteSource
     , vpnStaticRouteState :: VpnStaticRouteState
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VpnStaticRouteSource = VpnStaticRouteSourceStatic
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VpnStaticRouteState
     = VpnStaticRouteStatePending
     | VpnStaticRouteStateAvailable
     | VpnStaticRouteStateDeleting
     | VpnStaticRouteStateDeleted
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data RunInstancesRequest = RunInstancesRequest
     { runInstancesRequestImageId :: Text -- ^ Required
@@ -760,15 +787,15 @@
     , runInstancesRequestDisableApiTermination :: Maybe Bool
     , runInstancesRequestShutdownBehavior
         :: Maybe ShutdownBehavior
-    , runInstancesRequestPrivateIpAddress :: Maybe Text
+    , runInstancesRequestPrivateIpAddress :: Maybe IPv4
     , runInstancesRequestClientToken :: Maybe Text
-    , runInstancesRequestNetworkInterface
-        :: [NetworkInterfaceParam] -- ^ XXX: not implemented
+    , runInstancesRequestNetworkInterfaces
+        :: [NetworkInterfaceParam]
     , runInstancesRequestIamInstanceProfile
         :: Maybe IamInstanceProfile
     , runInstancesRequestEbsOptimized :: Maybe Bool
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data InstanceAttributeRequest
     = InstanceAttributeRequestInstanceType
@@ -789,7 +816,7 @@
     = ResetInstanceAttributeRequestKernel
     | ResetInstanceAttributeRequestRamdisk
     | ResetInstanceAttributeRequestSourceDestCheck
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data ModifyInstanceAttributeRequest
     = ModifyInstanceAttributeRequestInstanceType Text
@@ -805,7 +832,7 @@
     | ModifyInstanceAttributeRequestSourceDestCheck Bool
     | ModifyInstanceAttributeRequestGroupSet [Text]
     | ModifyInstanceAttributeRequestEbsOptimized Bool
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data RegisterImageRequest = RegisterImageRequest
     { registerImageRequestName :: Text
@@ -818,7 +845,7 @@
     , registerImageRequestBlockDeviceMappings
         :: [BlockDeviceMappingParam]
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data CreateVolumeRequest
     = CreateNewVolume
@@ -832,11 +859,11 @@
         , createFromSnapshotSize :: Maybe Int
         , createFromSnapshotVolumeType :: Maybe VolumeType
         }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data AssociateAddressRequest
     = AssociateAddressRequestEc2
-        { associateAddressRequestEc2PublicIp :: Text
+        { associateAddressRequestEc2PublicIp :: IPv4
         , associateAddressRequestEc2InstanceId :: Text
         }
     | AssociateAddressRequestVpc
@@ -844,43 +871,43 @@
         , associateAddressRequestVpcInstanceId :: Maybe Text
         , associateAddressRequestVpcNetworkInterfaceId
             :: Maybe Text
-        , associateAddressRequestVpcPrivateIpAddress :: Maybe Text
+        , associateAddressRequestVpcPrivateIpAddress :: Maybe IPv4
         , associateAddressRequestVpcAllowReassociation
             :: Maybe Bool
         }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data DisassociateAddressRequest
-    = DisassociateAddressRequestEc2 Text -- ^ PublicIp for EC2
-    | DisassociateAddressRequestVpc Text
+    = DisassociateAddressRequestEc2 IPv4 -- ^ PublicIp for EC2
+    | DisassociateAddressRequestVpc IPv4
       -- ^ AssociationId for VPC
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data SecurityGroupRequest
     = SecurityGroupRequestGroupId Text
     | SecurityGroupRequestGroupName Text
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data Subnet = Subnet
     { subnetId :: Text
     , subnetState :: SubnetState
     , subnetVpicId :: Text
-    , subnetCidrBlock :: Text
+    , subnetCidrBlock :: AddrRange IPv4
     , subnetAvailableIpAddressCount :: Int
     , subnetAvailabilityZone :: Text
     , subnetTagSet :: [ResourceTag]
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data SubnetState = SubnetStatePending | SubnetStateAvailable
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data CreateSubnetRequest = CreateSubnetRequest
     { createSubnetRequestVpcId :: Text
-    , createSubnetRequestCidrBlock :: Text
+    , createSubnetRequestCidrBlock :: AddrRange IPv4
     , createSubnetRequestAvailabilityZone :: Maybe Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VolumeStatus = VolumeStatus
     { volumeStatusVolumeId :: Text
@@ -889,25 +916,25 @@
     , volumeStatusEventSet :: [VolumeStatusEvent]
     , volumeStatusActionSet :: [VolumeStatusAction]
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VolumeStatusInfo = VolumeStatusInfo
     { volumeStatusInfoStatus :: VolumeStatusInfoStatus
     , volumeStatusInfoDetails :: [VolumeStatusDetail]
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VolumeStatusInfoStatus
     = VolumeStatusInfoStatusOK
     | VolumeStatusInfoStatusImpaired
     | VolumeStatusInfoStatusInsufficientData
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VolumeStatusDetail = VolumeStatusDetail
     { volumeStatusDetailName :: Text
     , volumeStatusDetailStatus :: Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VolumeStatusEvent = VolumeStatusEvent
     { volumeStatusEventType :: Text
@@ -916,7 +943,7 @@
     , volumeStatusEventNotBefore :: Maybe UTCTime
     , volumeStatusEventNotAfter :: Maybe UTCTime
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VolumeStatusAction = VolumeStatusAction
     { volumeStatusActionCode :: Text
@@ -924,17 +951,17 @@
     , volumeStatusActionEventId :: Text
     , volumeStatusActionDescription :: Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VolumeAttribute
     = VolumeAttributeAutoEnableIO Bool
     | VolumeAttributeProductCodes [ProductCode]
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VolumeAttributeRequest
     = VolumeAttributeRequestAutoEnableIO
     | VolumeAttributeRequestProductCodes
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data NetworkAcl = NetworkAcl
     { networkAclId :: Text
@@ -944,7 +971,7 @@
     , networkAclAssociationSet :: [NetworkAclAssociation]
     , networkAclTagSet :: [ResourceTag]
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data NetworkAclEntry = NetworkAclEntry
     { networkAclEntryRuleNumber :: Int
@@ -955,31 +982,31 @@
     , networkAclEntryIcmpTypeCode :: Maybe IcmpTypeCode
     , networkAclEntryPortRange :: Maybe PortRange
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data NetworkAclRuleAction
     = NetworkAclRuleActionAllow
     | NetworkAclRuleActionDeny
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data IcmpTypeCode = IcmpTypeCode
     { icmpTypeCodeCode :: Int
     , icmpTypeCodeType :: Int
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data PortRange = PortRange
     { portRangeFrom :: Int
     , portRangeTo :: Int
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data NetworkAclAssociation = NetworkAclAssociation
     { networkAclAssociationId :: Text
     , networkAclAssociationNetworkAclId :: Text
     , networkAclAssociationSubnetId :: Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data NetworkAclEntryRequest = NetworkAclEntryRequest
     { networkAclEntryRequestNetworkAclId :: Text
@@ -992,7 +1019,7 @@
     , networkAclEntryRequestIcmp :: Maybe IcmpTypeCode
     , networkAclEntryRequestPortRange :: Maybe PortRange
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data RouteTable = RouteTable
     { routeTableId :: Text
@@ -1002,7 +1029,7 @@
     , routeTablePropagatingVgw :: Maybe PropagatingVgw
     , routeTableTagSet :: [ResourceTag]
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data Route = Route
     { routeDestinationCidrBlock :: Text
@@ -1013,16 +1040,16 @@
     , routeState :: RouteState
     , routeOrigin :: Maybe RouteOrigin
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data RouteState = RouteStateActive | RouteStateBlackhole
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data RouteOrigin
     = RouteOriginCreateRouteTable
     | RouteOriginCreateRoute
     | RouteOriginTableEnableVgwRoutePropagation
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data RouteTableAssociation = RouteTableAssociation
     { routeTableAssociationId :: Text
@@ -1030,22 +1057,22 @@
     , routeTableAssociationSubnetId :: Maybe Text
     , routeTableAssociationMain :: Maybe Bool
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 type PropagatingVgw = Text
 
 data Vpc = Vpc
     { vpcId :: Text
     , vpcState :: VpcState
-    , vpcCidrBlock :: Text
+    , vpcCidrBlock :: AddrRange IPv4
     , vpcDhcpOptionsId :: Text
     , vpcTagSet :: [ResourceTag]
     , vpcInstanceTenancy :: Text
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VpcState = VpcStatePending | VpcStateAvailable
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VpnGateway = VpnGateway
     { vpnGatewayId :: Text
@@ -1055,27 +1082,27 @@
     , vpnGatewayAttachments :: [Attachment]
     , vpnGatewayTagSet :: [ResourceTag]
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data VpnGatewayState
     = VpnGatewayStatePending
     | VpnGatewayStateAvailable
     | VpnGatewayStateDeleting
     | VpnGatewayStateDeleted
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data Attachment = Attachment
     { attachmentVpcId :: Text
     , attachmentState :: AttachmentState
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data AttachmentState
     = AttachmentStateAttaching
     | AttachmentStateAttached
     | AttachmentStateDetaching
     | AttachmentStateDetached
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data CreateVpnGatewayType = CreateVpnGatewayTypeIpsec1
 
@@ -1083,31 +1110,31 @@
     { customerGatewayId :: Text
     , customerGatewayState :: CustomerGatewayState
     , customerGatewayType :: Text
-    , customerGatewayIpAddress :: Text
+    , customerGatewayIpAddress :: IPv4
     , customerGatewayBgpAsn :: Int
     , customerGatewayTagSet :: [ResourceTag]
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data CustomerGatewayState
     = CustomerGatewayStatePending
     | CustomerGatewayStateAvailable
     | CustomerGatewayStateDeleting
     | CustomerGatewayStateDeleted
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data InternetGateway = InternetGateway
     { internetGatewayInternetGatewayId :: Text
     , internetGatewayAttachmentSet :: [InternetGatewayAttachment]
     , internetGatewayTagSet :: [ResourceTag]
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data InternetGatewayAttachment = InternetGatewayAttachment
     { internetGatewayAttachmentVpcId :: Text
     , internetGatewayAttachmentState :: InternetGatewayAttachmentState
     }
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
 
 data InternetGatewayAttachmentState
     = InternetGatewayAttachmentStateAttaching
@@ -1115,4 +1142,149 @@
     | InternetGatewayAttachmentStateDetaching
     | InternetGatewayAttachmentStateDetached
     | InternetGatewayAttachmentStateAvailable
-  deriving (Show, Eq)
+  deriving (Show, Read, Eq)
+
+data NetworkInterface = NetworkInterface
+    { networkInterfaceId :: Text
+    , networkInterfaceSubnetId :: Text
+    , networkInterfaceVpcId :: Text
+    , networkInterfaceAvailabilityZone :: Text
+    , networkInterfaceDescription :: Text
+    , networkInterfaceOwnerId :: Text
+    , networkInterfaceRequesterId :: Maybe Text
+    , networkInterfaceRequesterManaged :: Text
+    , networkInterfaceStatus :: NetworkInterfaceStatus
+    , networkInterfaceMacAddress :: Text
+    , networkInterfacePrivateIpAddress :: IPv4
+    , networkInterfacePrivateDnsName :: Maybe Text
+    , networkInterfaceSourceDestCheck :: Bool
+    , networkInterfaceGroupSet :: [Group]
+    , networkInterfaceAttachment
+        :: Maybe NetworkInterfaceAttachment
+    , networkInterfaceAssociation
+        :: Maybe NetworkInterfaceAssociation
+    , networkInterfaceTagSet :: [ResourceTag]
+    , networkInterfacePrivateIpAddressesSet
+        :: [NetworkInterfacePrivateIpAddress]
+    }
+  deriving (Show, Read, Eq)
+
+type Filter = (Text, [Text])
+
+data NetworkInterfaceStatus
+    = NetworkInterfaceStatusAvailable
+    | NetworkInterfaceStatusInUse
+  deriving (Show, Read, Eq)
+
+data NetworkInterfaceAttachment = NetworkInterfaceAttachment
+    { networkInterfaceAttachmentId :: Text
+    , networkInterfaceAttachmentInstanceId :: Maybe Text
+    , networkInterfaceAttachmentInstanceOwnerId :: Text
+    , networkInterfaceAttachmentDeviceIndex :: Int
+    , networkInterfaceAttachmentStatus :: Text
+    , networkInterfaceAttachmentAttachTime :: UTCTime
+    , networkInterfaceAttachmentDeleteOnTermination :: Bool
+    }
+  deriving (Show, Read, Eq)
+
+data NetworkInterfaceAssociation = NetworkInterfaceAssociation
+    { networkInterfaceAssociationAttachmentId :: Maybe Text
+    , networkInterfaceAssociationInstanceId :: Maybe Text
+    , networkInterfaceAssociationPublicIp :: IPv4
+    , networkInterfaceAssociationIpOwnerId :: Text
+    , networkInterfaceAssociationId :: Text
+    }
+  deriving (Show, Read, Eq)
+
+data NetworkInterfacePrivateIpAddress
+    = NetworkInterfacePrivateIpAddress
+    { networkInterfacePrivateIpAddressPrivateIpAddress :: IPv4
+    , networkInterfacePrivateIpAddressPrimary :: Bool
+    , networkInterfacePrivateIpAddressAssociation
+        :: Maybe NetworkInterfaceAssociation
+    }
+  deriving (Show, Read, Eq)
+
+instance FromText Platform
+  where
+    fromMaybeText Nothing  = return PlatformOther
+    fromMaybeText (Just t)
+        | t == "windows" = return PlatformWindows
+        | otherwise      = return PlatformOther
+
+instance FromText AddressDomain
+  where
+    fromMaybeText Nothing  = return AddressDomainStandard
+    fromMaybeText (Just t)
+        | t == "standard" = return AddressDomainStandard
+        | t == "vpc"      = return AddressDomainVPC
+        | otherwise       = monadThrow $ TextConversionException t
+
+instance FromText EC2Return
+  where
+    fromTextMay t
+        | t == "true" = Just EC2Success
+        | otherwise   = Just $ EC2Error t
+
+instance FromText InstanceLifecycle
+  where
+    fromMaybeText Nothing  = return LifecycleNone
+    fromMaybeText (Just t)
+        | t == "spot" = return LifecycleSpot
+        | otherwise   = monadThrow $ TextConversionException t
+
+deriveFromText "ImageState" ["available", "pending", "failed"]
+deriveFromText "ProductCodeType" ["devpay", "marketplace"]
+deriveFromText "ImageType" ["machine", "kernel", "ramdisk"]
+deriveFromText "RootDeviceType" ["ebs", "instance-store"]
+deriveFromText "VirtualizationType" ["paravirtual", "hvm"]
+deriveFromText "Hypervisor" ["ovm", "xen"]
+deriveFromText "InstanceStatusEventCode"
+    [ "instance-reboot"
+    , "instance-stop"
+    , "system-reboot"
+    , "instance-retirement"
+    ]
+deriveFromText "InstanceStatusTypeStatus"
+    ["ok", "impaired", "insufficient-data", "not-applicable"]
+deriveFromText "InstanceMonitoringState"
+    ["disabled", "enabled", "pending"]
+deriveFromText "Architecture" ["i386", "x86_64"]
+deriveFromText "SnapshotStatus" ["pending", "completed", "error"]
+deriveFromText "VolumeState"
+    [ "creating"
+    , "available"
+    , "in-use"
+    , "deleting"
+    , "deleted"
+    , "error"
+    ]
+deriveFromText "AttachmentSetItemResponseStatus"
+    ["attaching", "attached", "detaching", "detached"]
+deriveFromText "ShutdownBehavior" ["stop", "terminate"]
+deriveFromText "VpnConnectionState"
+    ["pending", "available", "deleting", "deleted"]
+deriveFromText "VpnTunnelTelemetryStatus" ["UP", "DOWN"]
+deriveFromText "VpnStaticRouteSource" ["Static"]
+deriveFromText "VpnStaticRouteState"
+    ["pending", "available", "deleting", "deleted"]
+deriveFromText "SubnetState" ["pending", "available"]
+deriveFromText "VolumeStatusInfoStatus"
+    ["ok", "impaired", "insufficient-data"]
+deriveFromText "NetworkAclRuleAction" ["allow", "deny"]
+deriveFromText "RouteState" ["active", "blackhole"]
+deriveFromText "RouteOrigin"
+    [ "CreateRouteTable"
+    , "CreateRoute"
+    , "EnableVgwRoutePropagation"
+    ]
+deriveFromText "VpcState" ["pending", "available"]
+deriveFromText "VpnGatewayState"
+    ["pending", "available", "deleting", "deleted"]
+deriveFromText "AttachmentState"
+    ["attaching", "attached", "detaching", "detached"]
+deriveFromText "CustomerGatewayState"
+    ["pending", "available", "deleting", "deleted"]
+deriveFromText "InternetGatewayAttachmentState"
+    ["attaching", "attached", "detaching", "detached", "available"]
+deriveFromText "NetworkInterfaceStatus" ["available", "in-use"]
diff --git a/AWS/EC2/Util.hs b/AWS/EC2/Util.hs
--- a/AWS/EC2/Util.hs
+++ b/AWS/EC2/Util.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE FlexibleContexts #-}
+{-# LANGUAGE FlexibleContexts, ScopedTypeVariables #-}
 
 module AWS.EC2.Util
     ( list
@@ -8,6 +8,8 @@
     , wait
     , count
     , findTag
+    , sleep
+    , retry
     ) where
 
 import Data.Conduit
@@ -22,6 +24,8 @@
 import Control.Applicative
 import Control.Parallel (par)
 import Data.List (find)
+import qualified Control.Exception.Lifted as E
+import Control.Monad.Trans.Control (MonadBaseControl)
 
 import AWS.EC2.Internal
 import AWS.EC2.Types (ResourceTag(resourceTagKey))
@@ -111,3 +115,20 @@
 findTag key tags = find f tags
   where
     f t = resourceTagKey t == key
+
+sleep :: MonadIO m => Int -> EC2 m ()
+sleep sec = liftIO $ CC.threadDelay $ sec * 1000 * 1000
+
+retry
+    :: forall m a. (MonadBaseControl IO m, MonadResource m)
+    => Int -- ^ sleep count
+    -> Int -- ^ number of retry
+    -> EC2 m a
+    -> EC2 m a
+retry _   0   f = f
+retry sec cnt f = f `E.catch` handler
+  where
+    handler :: E.SomeException -> EC2 m a
+    handler _ = do
+        sleep sec
+        retry sec (cnt - 1) f
diff --git a/AWS/EC2/VPC.hs b/AWS/EC2/VPC.hs
--- a/AWS/EC2/VPC.hs
+++ b/AWS/EC2/VPC.hs
@@ -19,13 +19,12 @@
     ) where
 
 import Data.Text (Text)
-
 import Data.XML.Types (Event)
 import Data.Conduit
+import Data.IP (IPv4, AddrRange)
 import Control.Monad.Trans.Control (MonadBaseControl)
 import Control.Applicative
 
-import AWS.EC2.Convert
 import AWS.EC2.Internal
 import AWS.EC2.Types
 import AWS.EC2.Query
@@ -43,8 +42,7 @@
     -> Text -- ^ VpcId
     -> EC2 m Bool
 attachInternetGateway internetGatewayId vid =
-    ec2Query "AttachInternetGateway" params $
-        getF "return" textToBool
+    ec2Query "AttachInternetGateway" params $ getT "return"
   where
     params =
         [ ValueParam "InternetGatewayId" internetGatewayId
@@ -59,8 +57,7 @@
     -> Text -- ^ VpcId
     -> EC2 m Bool
 detachInternetGateway internetGatewayId vid =
-    ec2Query "DetachInternetGateway" params $
-        getF "return" textToBool
+    ec2Query "DetachInternetGateway" params $ getT "return"
   where
     params =
         [ ValueParam "InternetGatewayId" internetGatewayId
@@ -113,7 +110,7 @@
     => GLSink Event m InternetGatewayAttachment
 internetGatewayAttachmentSink = InternetGatewayAttachment
     <$> getT "vpcId"
-    <*> getF "state" internetGatewayAttachmentState'
+    <*> getT "state"
 describeVpnConnections
     :: (MonadBaseControl IO m, MonadResource m)
     => [Text] -- ^ VpnConnectionIds
@@ -133,7 +130,7 @@
     <$> do
         a <- getT "vpnConnectionId"
         traceShow a $ return a
-    <*> getF "state" vpnConnectionState'
+    <*> getT "state"
     <*> getT "customerGatewayConfiguration"
     <*> getT "type"
     <*> getT "customerGatewayId"
@@ -142,20 +139,20 @@
     <*> itemsSet "vgwTelemetry"
         (VpnTunnelTelemetry
         <$> getT "outsideIpAddress"
-        <*> getF "status" vpnTunnelTelemetryStatus'
-        <*> getF "lastStatusChange" textToTime
+        <*> getT "status"
+        <*> getT "lastStatusChange"
         <*> getT "statusMessage"
-        <*> getF "acceptedRouteCount" textToInt
+        <*> getT "acceptedRouteCount"
         )
     <*> elementM "options"
         (VpnConnectionOptionsRequest
-        <$> getF "staticRoutesOnly" textToBool
+        <$> getT "staticRoutesOnly"
         )
     <*> elementM "routes"
         (VpnStaticRoute
         <$> getT "destinationCidrBlock"
-        <*> getF "source" vpnStaticRouteSource'
-        <*> getF "state" vpnStaticRouteState'
+        <*> getT "source"
+        <*> getT "state"
         )
 
 ------------------------------------------------------------
@@ -179,7 +176,7 @@
     => GLSink Event m Vpc
 vpcSink = Vpc
     <$> getT "vpcId"
-    <*> getF "state" vpcState'
+    <*> getT "state"
     <*> getT "cidrBlock"
     <*> getT "dhcpOptionsId"
     <*> resourceTagSink
@@ -190,7 +187,7 @@
 ------------------------------------------------------------
 createVpc
     :: (MonadResource m, MonadBaseControl IO m)
-    => Text -- ^ CidrBlock
+    => AddrRange IPv4 -- ^ CidrBlock
     -> Maybe Text -- ^ instanceTenancy
     -> EC2 m Vpc
 createVpc cidrBlock instanceTenancy =
@@ -198,7 +195,7 @@
         element "vpc" vpcSink
   where
     params =
-        [ ValueParam "CidrBlock" cidrBlock
+        [ ValueParam "CidrBlock" $ toText cidrBlock
         ] ++ maybeParams [ ("instanceTenancy", instanceTenancy) ]
 
 ------------------------------------------------------------
@@ -231,9 +228,9 @@
     => GLSink Event m VpnGateway
 vpnGatewaySink = VpnGateway
     <$> getT "vpnGatewayId"
-    <*> getF "state" vpnGatewayState'
+    <*> getT "state"
     <*> getT "type"
-    <*> getMT "availabilityZone"
+    <*> getT "availabilityZone"
     <*> itemsSet "attachments" attachmentSink
     <*> resourceTagSink
 
@@ -241,7 +238,7 @@
     => GLSink Event m Attachment
 attachmentSink = Attachment
     <$> getT "vpcId"
-    <*> getF "state" attachmentState'
+    <*> getT "state"
 
 ------------------------------------------------------------
 -- createVpnGateway
@@ -289,10 +286,10 @@
     => GLSink Event m CustomerGateway
 customerGatewaySink = CustomerGateway
     <$> getT "customerGatewayId"
-    <*> getF "state" customerGatewayState'
+    <*> getT "state"
     <*> getT "type"
     <*> getT "ipAddress"
-    <*> getF "bgpAsn" textToInt
+    <*> getT "bgpAsn"
     <*> resourceTagSink
 
 ------------------------------------------------------------
@@ -301,7 +298,7 @@
 createCustomerGateway
     :: (MonadResource m, MonadBaseControl IO m)
     => Text -- ^ Type
-    -> Text -- ^ IpAddress
+    -> IPv4 -- ^ IpAddress
     -> Int -- ^ BgpAsn
     -> EC2 m CustomerGateway
 createCustomerGateway type' ipAddr bgpAsn = do
@@ -310,7 +307,7 @@
   where
     params =
         [ ValueParam "Type" type' 
-        , ValueParam "IpAddress" ipAddr
+        , ValueParam "IpAddress" $ toText ipAddr
         , ValueParam "BgpAsn" (toText bgpAsn)
         ]
 
diff --git a/AWS/EC2/Volume.hs b/AWS/EC2/Volume.hs
--- a/AWS/EC2/Volume.hs
+++ b/AWS/EC2/Volume.hs
@@ -18,7 +18,6 @@
 import Control.Monad.Trans.Control (MonadBaseControl)
 import Control.Applicative
 
-import AWS.EC2.Convert
 import AWS.EC2.Internal
 import AWS.EC2.Types
 import AWS.EC2.Query
@@ -43,11 +42,11 @@
     => GLSink Event m Volume
 volumeSink = Volume
     <$> getT "volumeId"
-    <*> getF "size" textToInt
-    <*> getMT "snapshotId"
+    <*> getT "size"
+    <*> getT "snapshotId"
     <*> getT "availabilityZone"
-    <*> getF "status" volumeStatus'
-    <*> getF "createTime" textToTime
+    <*> getT "status"
+    <*> getT "createTime"
     <*> itemsSet "attachmentSet" attachmentSink
     <*> resourceTagSink
     <*> volumeTypeSink
@@ -57,9 +56,9 @@
     <$> getT "volumeId"
     <*> getT "instanceId"
     <*> getT "device"
-    <*> getF "status" attachmentSetItemResponseStatus'
-    <*> getF "attachTime" textToTime
-    <*> getM "deleteOnTermination" (textToBool <$>)
+    <*> getT "status"
+    <*> getT "attachTime"
+    <*> getT "deleteOnTermination"
 
 volumeTypeParam :: VolumeType -> [QueryParam]
 volumeTypeParam VolumeTypeStandard =
@@ -149,7 +148,7 @@
     <$> getT "volumeId"
     <*> getT "availabilityZone"
     <*> element "volumeStatus" (VolumeStatusInfo
-        <$> getF "status" volumeStatusInfoStatus'
+        <$> getT "status"
         <*> itemsSet "details" (VolumeStatusDetail
             <$> getT "name"
             <*> getT "status"
@@ -159,8 +158,8 @@
         <$> getT "eventType"
         <*> getT "eventId"
         <*> getT "description"
-        <*> getM "notBefore" (textToTime <$>)
-        <*> getM "notAfter" (textToTime <$>)
+        <*> getT "notBefore"
+        <*> getT "notAfter"
         )
     <*> itemsSet "actionsSet" (VolumeStatusAction
         <$> getT "code"
@@ -175,7 +174,7 @@
     -> Bool -- ^ AutoEnableIO
     -> EC2 m Bool
 modifyVolumeAttribute vid enable =
-    ec2Query "ModifyVolumeAttribute" params returnBool
+    ec2Query "ModifyVolumeAttribute" params $ getT "return"
   where
     params =
         [ ValueParam "VolumeId" vid
@@ -187,7 +186,7 @@
     => Text -- ^ VolumeId
     -> EC2 m Bool
 enableVolumeIO vid =
-    ec2Query "EnableVolumeIO" params returnBool
+    ec2Query "EnableVolumeIO" params $ getT "return"
   where
     params = [ValueParam "VolumeId" vid]
 
@@ -215,8 +214,7 @@
     -> GLSink Event m VolumeAttribute
 volumeAttributeSink VolumeAttributeRequestAutoEnableIO
     = VolumeAttributeAutoEnableIO
-    <$> element "autoEnableIO"
-        (getF "value" textToBool)
+    <$> element "autoEnableIO" (getT "value")
 volumeAttributeSink VolumeAttributeRequestProductCodes
     = VolumeAttributeProductCodes
     <$> productCodeSink
diff --git a/AWS/ELB.hs b/AWS/ELB.hs
--- a/AWS/ELB.hs
+++ b/AWS/ELB.hs
@@ -18,7 +18,7 @@
 import Data.Monoid
 
 import AWS.Class
-import AWS.Util
+import AWS.Lib.Query (textToBS)
 
 import AWS
 import AWS.ELB.Internal
diff --git a/AWS/ELB/LoadBalancer.hs b/AWS/ELB/LoadBalancer.hs
--- a/AWS/ELB/LoadBalancer.hs
+++ b/AWS/ELB/LoadBalancer.hs
@@ -10,7 +10,6 @@
 import Control.Monad.Trans.Control (MonadBaseControl)
 import Data.XML.Types (Event(..))
 
-import AWS.Util
 import AWS.Lib.Parser
 import AWS.Lib.Query
 
@@ -34,26 +33,26 @@
     LoadBalancerDescription
     <$> members "SecurityGroups" text
     <*> getT "LoadBalancerName"
-    <*> getF "CreatedTime" textToTime
+    <*> getT "CreatedTime"
     <*> element "HealthCheck"
         (HealthCheck
-        <$> getF "Interval" textToInt
+        <$> getT "Interval"
         <*> getT "Target"
-        <*> getF "HealthyThreshold" textToInt
-        <*> getF "Timeout" textToInt
-        <*> getF "UnhealthyThreshold" textToInt
+        <*> getT "HealthyThreshold"
+        <*> getT "Timeout"
+        <*> getT "UnhealthyThreshold"
         )
-    <*> getMT "VPCId"
+    <*> getT "VPCId"
     <*> members "ListenerDescriptions"
         (ListenerDescription
         <$> members "PolicyNames" text
         <*> element "Listener"
             (Listener
             <$> getT "Protocol"
-            <*> getF "LoadBalancerPort" textToInt
+            <*> getT "LoadBalancerPort"
             <*> getT "InstanceProtocol"
-            <*> getMT "SSLCertificateId"
-            <*> getF "InstancePort" textToInt
+            <*> getT "SSLCertificateId"
+            <*> getT "InstancePort"
             )
         )
     <*> members "Instances"
@@ -68,7 +67,7 @@
         <*> members "OtherPolicies" text
         <*> members "LBCookieStickinessPolicies"
             (LBCookieStickinessPolicy
-            <$> getF "CookieExpirationPeriod" textToInt
+            <$> getT "CookieExpirationPeriod"
             <*> getT "PolicyName"
             )
         )
@@ -84,7 +83,7 @@
     <*> getT "DNSName"
     <*> members "BackendServerDescriptions"
         (BackendServerDescription
-        <$> getF "InstancePort" textToInt
+        <$> getT "InstancePort"
         <*> members "PolicyNames" text
         )
     <*> members "Subnets" text
diff --git a/AWS/Lib/Convert.hs b/AWS/Lib/Convert.hs
deleted file mode 100644
--- a/AWS/Lib/Convert.hs
+++ /dev/null
@@ -1,24 +0,0 @@
-{-# LANGUAGE RankNTypes, OverloadedStrings, TemplateHaskell #-}
-
-module AWS.Lib.Convert
-    where
-
-import Language.Haskell.TH
-import Control.Applicative ((<$>))
-import Data.Text (Text)
-
-import AWS.Util
-
-mkConvertFunc :: String -> Name -> [String] -> Q [Dec]
-mkConvertFunc fs d strs = runQ $ do
-  v <- newName "v"
-  ctrs <- (\(TyConI (DataD [] _ [] x [])) -> map (\(NormalC name []) -> name) x)
-          <$> reify d
-  return $
-      [ SigD (mkName fs) (AppT (AppT ArrowT (ConT ''Text)) (ConT d))
-      , FunD (mkName fs) [Clause [VarP v] (NormalB
-        (CaseE (VarE v)
-           $ (map (\(s,t) -> Match (LitP (StringL s)) (NormalB (ConE t)) []) $ zip strs ctrs)
-           ++ [Match WildP (NormalB (AppE (AppE (VarE 'err) (LitE (StringL $ show d))) (LitE (StringL $ show v)))) []])
-      ) []]
-      ]
diff --git a/AWS/Lib/FromText.hs b/AWS/Lib/FromText.hs
new file mode 100644
--- /dev/null
+++ b/AWS/Lib/FromText.hs
@@ -0,0 +1,83 @@
+{-# LANGUAGE RankNTypes, OverloadedStrings, TemplateHaskell, FlexibleInstances #-}
+
+module AWS.Lib.FromText
+    where
+
+import Control.Applicative ((<$>))
+import Control.Monad
+import Data.Conduit (MonadThrow)
+import Data.IP (IPv4, AddrRange)
+import Data.Text (Text)
+import qualified Data.Text as T
+import Data.Time (UTCTime)
+import qualified Data.Time as Time
+import qualified Data.Time.Parse as TP
+import Language.Haskell.TH
+import Safe
+
+import AWS.Class
+
+class Read a => FromText a
+  where
+    fromText :: MonadThrow m => Text -> m a
+    fromText t
+        = maybe (monadThrow $ TextConversionException t) return
+        . fromTextMay
+        $ t
+
+    fromTextMay :: Text -> Maybe a
+    fromTextMay = readMay . T.unpack
+
+    fromMaybeText :: MonadThrow m => Maybe Text -> m a
+    fromMaybeText
+        = maybe
+            (monadThrow $ TextConversionException "no text")
+            fromText
+
+instance FromText a => FromText (Maybe a)
+  where
+    fromText = return . join . fromTextMay
+    fromMaybeText Nothing  = return Nothing
+    fromMaybeText (Just t) = fromText t >>= return . Just
+    fromTextMay = Just . fromTextMay
+
+instance FromText Int
+instance FromText Integer
+instance FromText Double
+instance FromText IPv4
+instance FromText (AddrRange IPv4)
+
+instance FromText Text
+  where
+    fromTextMay = Just
+
+instance FromText Bool
+  where
+    fromTextMay "true"  = Just True
+    fromTextMay "false" = Just False
+    fromTextMay _       = Nothing
+
+instance FromText UTCTime
+  where
+    fromTextMay t
+        = Time.localTimeToUTC Time.utc . fst
+        <$> (TP.strptime fmt $ T.unpack t)
+      where
+        fmt = "%FT%T"
+
+deriveFromText :: String -> [String] -> DecsQ
+deriveFromText dstr strs = do
+    ctrs <- map (\(NormalC name _) -> name) <$> cons
+    x <- newName "x"
+    let cases = caseE (varE x) (map f (zip strs ctrs) ++ [wild])
+    let fun = funD 'fromTextMay [clause [varP x] (normalB cases) []]
+    (:[]) <$> instanceD ctx typ [fun]
+  where
+    d = mkName dstr
+    cons = do
+        (TyConI (DataD _ _ _ cs _)) <- reify d
+        return cs
+    f (s, t) = match (litP $ stringL s) (normalB $ [|Just $(conE t)|]) []
+    wild = match wildP (normalB [|Nothing|]) []
+    typ = appT (conT ''FromText) (conT d)
+    ctx = return []
diff --git a/AWS/Lib/Parser.hs b/AWS/Lib/Parser.hs
--- a/AWS/Lib/Parser.hs
+++ b/AWS/Lib/Parser.hs
@@ -1,11 +1,28 @@
-{-# LANGUAGE FlexibleContexts #-}
-{-# LANGUAGE RankNTypes #-}
+{-# LANGUAGE FlexibleContexts, RankNTypes, ScopedTypeVariables, FlexibleInstances #-}
+{-# LANGUAGE UndecidableInstances #-}
+
 module AWS.Lib.Parser
-    where
+    ( RequestId
+    , getT
+    , getT_
+    , element
+    , elementM
+    , listConduit
+    , listConsumer
+    , isBeginTagName
+    , awaitWhile
+    , sinkResponse
+    , sinkResponseMetadata
+    , sinkError
+    , sinkEventBeginDocument
+    , members
+    , text
+    , FromText(..)
+    ) where
 
 import Data.XML.Types (Event(..), Name(..))
 import Data.Text (Text)
-import qualified Data.Text as T
+import Data.ByteString (ByteString)
 import Data.Conduit
 import qualified Data.Conduit.List as CL
 import qualified Text.XML.Stream.Parse as XML
@@ -14,6 +31,7 @@
 import Control.Monad.Trans.Class (lift)
 
 import AWS.Class
+import AWS.Lib.FromText
 
 type RequestId = Text
 
@@ -67,29 +85,17 @@
         | f a       = return $ Just a
         | otherwise = awaitWhile f
 
-getF :: MonadThrow m
-    => Text
-    -> (Text -> b)
-    -> Pipe Event Event o u m b
-getF name f = tagContent name >>= return . f
-
-getT :: MonadThrow m
-    => Text
-    -> Pipe Event Event o u m Text
-getT name = getF name id
-
-getM :: MonadThrow m
+getT :: (MonadThrow m, FromText a)
     => Text
-    -> (Maybe Text -> b)
-    -> Pipe Event Event o u m b
-getM name f = tagContentM name >>= return . f
+    -> Pipe Event Event o u m a
+getT name = elementM name text >>= lift . fromMaybeText
 
-getMT :: MonadThrow m
+getT_ :: forall m o u . MonadThrow m
     => Text
-    -> Pipe Event Event o u m (Maybe Text)
-getMT name = getM name id
+    -> Pipe Event Event o u m ()
+getT_ name = () <$ (getT name :: Pipe Event Event o u m Text)
 
-elementM :: MonadThrow m
+elementM :: forall o u m a . MonadThrow m
     => Text
     -> Pipe Event Event o u m a
     -> Pipe Event Event o u m (Maybe a)
@@ -99,22 +105,12 @@
   where
     g n = (nameLocalName n == name)
 
-element :: MonadThrow m
+element :: forall o u m a . MonadThrow m
     => Text
     -> Pipe Event Event o u m a
     -> Pipe Event Event o u m a
-element name inner = XML.force ("parse error:" ++ T.unpack name) $ elementM name inner
-
-tagContentM :: MonadThrow m
-    => Text
-    -> GLSink Event m (Maybe Text)
-tagContentM name = elementM name text
-
-tagContent :: MonadThrow m
-    => Text
-    -> GLSink Event m Text
-tagContent name =
-    XML.force ("parse error:" ++ T.unpack name) $ tagContentM name
+element name inner = elementM name inner >>=
+    maybe (lift $ monadThrow $ ResponseParseError name) return
 
 sinkResponse
     :: MonadThrow m
@@ -144,15 +140,13 @@
         Just EventBeginDocument -> return ()
         Just _ -> fail $ "unexpected: " <> show me
 
-sinkError :: MonadThrow m => Int -> GLSink Event m a
-sinkError status = element "ErrorResponse" $ do
-    (_t,c,m) <- element "Error" $
-        (,,)
-        <$> getT "Type"
-        <*> getT "Code"
+sinkError :: MonadThrow m => ByteString -> Int -> GLSink Event m a
+sinkError action status = element "ErrorResponse" $ do
+    (c,m) <- element "Error" $ (,)
+        <$> (getT_ "Type" *> getT "Code")
         <*> getT "Message"
     rid <- getT "RequestId"
-    lift $ monadThrow $ ClientError status c m rid
+    lift $ monadThrow $ ClientError action status c m rid
 
 members :: MonadThrow m
     => Text
diff --git a/AWS/Lib/Query.hs b/AWS/Lib/Query.hs
--- a/AWS/Lib/Query.hs
+++ b/AWS/Lib/Query.hs
@@ -1,6 +1,5 @@
 {-# LANGUAGE FlexibleContexts, RankNTypes, CPP #-}
 
-#define DEBUG
 module AWS.Lib.Query
     ( requestQuery
     , QueryParam(..)
@@ -10,12 +9,15 @@
 #ifdef DEBUG
     , debugQuery
 #endif
+    , textToBS
     ) where
 
 import           Data.ByteString (ByteString)
 import qualified Data.ByteString as BS
 import           Data.ByteString.Lazy.Char8 ()
 import qualified Data.ByteString.Char8 as BSC
+import Data.Text (Text)
+import qualified Data.Text as T
 
 import Data.Monoid
 import Data.XML.Types (Event(..))
@@ -33,7 +35,6 @@
 import Control.Monad.IO.Class (MonadIO, liftIO)
 import Control.Monad.Trans.Class (lift)
 import Control.Exception.Lifted as E
-import Data.Text (Text)
 import qualified Control.Monad.State as State
 import qualified Control.Monad.Reader as Reader
 
@@ -41,13 +42,12 @@
 import AWS.Util
 import AWS.Credential
 import AWS.Lib.Parser
+import AWS.EC2.Types (Filter)
 
 #ifdef DEBUG
 import qualified Data.Conduit.Binary as CB
 #endif
 
-type Filter = (Text, [Text])
-
 data QueryParam
     = ArrayParams Text [Text]
     | FilterParams [Filter]
@@ -89,6 +89,9 @@
     qheader = Map.fromList $ queryHeader action time cred ver
     qparam = queryStr $ Map.unions (qheader : map toArrayParams params)
 
+textToBS :: Text -> ByteString
+textToBS = BSC.pack . T.unpack
+
 toArrayParams :: QueryParam -> Map ByteString ByteString
 toArrayParams (ArrayParams name params) = Map.fromList 
     [ (textToBS name <> "." <> bsShow i, textToBS param)
@@ -155,7 +158,7 @@
     -> ByteString
     -> [QueryParam]
     -> ByteString
-    -> (Int -> GLSink Event m a)
+    -> (ByteString -> Int -> GLSink Event m a)
     -> m (ResumableSource m ByteString)
 requestQuery cred ctx action params ver errSink = do
     let mgr = manager ctx
@@ -170,7 +173,7 @@
     if st < 400
         then return body
         else do
-            clientError st body errSink
+            clientError st body $ errSink action
             fail "not reached"
 
 maybeParams :: [(Text, Maybe Text)] -> [QueryParam]
diff --git a/AWS/RDS.hs b/AWS/RDS.hs
--- a/AWS/RDS.hs
+++ b/AWS/RDS.hs
@@ -18,7 +18,7 @@
 import Data.Monoid ((<>))
 
 import AWS.Class
-import AWS.Util
+import AWS.Lib.Query (textToBS)
 
 import AWS
 import AWS.RDS.Internal
diff --git a/AWS/RDS/DBInstance.hs b/AWS/RDS/DBInstance.hs
--- a/AWS/RDS/DBInstance.hs
+++ b/AWS/RDS/DBInstance.hs
@@ -38,9 +38,9 @@
     => GLSink Event m [DBInstance]
 sinkDBInstances = elements "DBInstance" $
     DBInstance
-    <$> getM "Iops" (textToInt <$>)
-    <*> getF "BackupRetentionPeriod" textToInt
-    <*> getF "MultiAZ" textToBool
+    <$> getT "Iops"
+    <*> getT "BackupRetentionPeriod"
+    <*> getT "MultiAZ"
     <*> getT "DBInstanceStatus"
     <*> getT "DBInstanceIdentifier"
     <*> getT "PreferredBackupWindow"
@@ -51,11 +51,11 @@
         <*> getT "Status"
         )
     <*> getT "AvailabilityZone"
-    <*> getM "LatestRestorableTime" (textToTime <$>)
+    <*> getT "LatestRestorableTime"
     <*> elements "ReadReplicaDBInstanceIdentifier" text
     <*> getT "Engine"
     <*> sinkPendingModifiedValues
-    <*> getMT "CharacterSetName"
+    <*> getT "CharacterSetName"
     <*> getT "LicenseModel"
     <*> elementM "DBSubnetGroup"
         (DBSubnetGroup
@@ -70,7 +70,7 @@
             <*> element "SubnetAvailabilityZone"
                 (AvailabilityZone
                 <$> getT "Name"
-                <*> getF "ProvisionedIopsCapable" textToBool
+                <*> getT "ProvisionedIopsCapable"
                 )
             )
         )
@@ -81,20 +81,20 @@
         )
     <*> elementM "Endpoint"
         (Endpoint
-        <$> getF "Port" textToInt
+        <$> getT "Port"
         <*> getT "Address"
         )
     <*> getT "EngineVersion"
-    <*> getMT "ReadReplicaSourceDBInstanceIdentifier"
+    <*> getT "ReadReplicaSourceDBInstanceIdentifier"
     <*> elements "DBSecurityGroup"
         (DBSecurityGroupMembership
         <$> getT "Status"
         <*> getT "DBSecurityGroupName"
         )
-    <*> getMT "DBName"
-    <*> getF "AutoMinorVersionUpgrade" textToBool
-    <*> getM "InstanceCreateTime" (textToTime <$>)
-    <*> getF "AllocatedStorage" textToInt
+    <*> getT "DBName"
+    <*> getT "AutoMinorVersionUpgrade"
+    <*> getT "InstanceCreateTime"
+    <*> getT "AllocatedStorage"
     <*> getT "DBInstanceClass"
     <*> getT "MasterUsername" 
 
@@ -102,15 +102,15 @@
     :: MonadThrow m
     => GLSink Event m [PendingModifiedValue]
 sinkPendingModifiedValues = element "PendingModifiedValues" $
-    catMaybes <$> sequence [ m "MasterUserPassword" PMVMasterUserPassword
-        , m "Iops" (PMVIops . textToInt)
-        , m "MultiAZ" (PMVMultiAZ . textToBool)
-        , m "AllocatedStorage" (PMVAllocatedStorage . textToInt)
-        , m "EngineVersion" PMVEngineVersion
-        , m "DBInstanceClass" PMVDBInstanceClass
-        , m "BackupRetentionPeriod"
-            (PMVBackupRetentionPeriod . textToInt)
-        , m "Port" (PMVPort . textToInt)
+    catMaybes <$> sequence
+        [ f PMVMasterUserPassword "MasterUserPassword"
+        , f PMVIops "Iops"
+        , f PMVMultiAZ "MultiAZ"
+        , f PMVAllocatedStorage "AllocatedStorage"
+        , f PMVEngineVersion "EngineVersion"
+        , f PMVDBInstanceClass "DBInstanceClass"
+        , f PMVBackupRetentionPeriod "BackupRetentionPeriod"
+        , f PMVPort "Port"
         ]
   where
-    m t f = getM t (f <$>)
+    f c name = fmap c <$> getT name
diff --git a/AWS/Util.hs b/AWS/Util.hs
--- a/AWS/Util.hs
+++ b/AWS/Util.hs
@@ -6,10 +6,8 @@
 import qualified Data.ByteString.Lazy as BSL
 import Data.Text (Text)
 import qualified Data.Text as T
-import qualified Data.Text.Read as TR
 import Data.Time (UTCTime)
 import qualified Data.Time as Time
-import qualified Data.Time.Parse as TP
 import System.Locale (defaultTimeLocale)
 
 toS :: BSL.ByteString -> ByteString
@@ -24,33 +22,6 @@
 err :: String -> Text -> a
 err v m = error $ "unknown " ++ v ++ ": " ++ T.unpack m
 
-textToBool :: Text -> Bool
-textToBool a
-    | a == "true"  = True
-    | a == "false" = False
-    | otherwise    = err "value" a
-
-textToInt :: Integral a => Text -> a
-textToInt t = either 
-    (const $ error "not decimal")
-    fst
-    (TR.signed TR.decimal t)
-
-textToDouble :: Fractional a => Text -> a
-textToDouble t = either
-    (const $ error "not double value")
-    fst
-    (TR.signed TR.rational t)
-
-textToTime :: Text -> UTCTime
-textToTime
-    = Time.localTimeToUTC Time.utc
-    . maybe (error "time format error.") fst
-    . TP.strptime fmt
-    . T.unpack
-  where
-    fmt = "%FT%T"
-
 timeToText :: UTCTime -> Text
 timeToText
     = T.pack
@@ -58,9 +29,6 @@
   where
     fmt = "%FT%T"
 
-orEmpty :: Maybe Text -> Text
-orEmpty = maybe "" id
-
 boolToText :: Bool -> Text
 boolToText True  = "true"
 boolToText False = "false"
@@ -71,5 +39,5 @@
 bsToText :: ByteString -> Text
 bsToText = T.pack . BSC.unpack
 
-textToBS :: Text -> ByteString
-textToBS = BSC.pack . T.unpack
+unconcat :: [a] -> [[a]]
+unconcat = map (:[])
diff --git a/Tests/Main.hs b/Tests/Main.hs
--- a/Tests/Main.hs
+++ b/Tests/Main.hs
@@ -22,3 +22,4 @@
     runAvailabilityZoneTests
     runTagTests
     runKeyPairTests
+    runNetworkInterfaceTests
diff --git a/aws-sdk.cabal b/aws-sdk.cabal
--- a/aws-sdk.cabal
+++ b/aws-sdk.cabal
@@ -1,5 +1,5 @@
 name:                aws-sdk
-version:             0.7.0.0
+version:             0.7.1.0
 synopsis:            AWS SDK for Haskell
 description:         An AWS(Amazon Web Services) liblary for Haskell.
 license:             BSD3
@@ -30,7 +30,6 @@
                    , AWS.EC2.Internal
                    , AWS.EC2.Address
                    , AWS.EC2.AvailabilityZone
-                   , AWS.EC2.Convert
                    , AWS.EC2.Image
                    , AWS.EC2.Instance
                    , AWS.EC2.Volume
@@ -43,9 +42,10 @@
                    , AWS.EC2.Region
                    , AWS.EC2.VPC
                    , AWS.EC2.Acl
+                   , AWS.EC2.NetworkInterface
                    , AWS.EC2.Tag
                    , AWS.EC2.Params
-                   , AWS.Lib.Convert
+                   , AWS.Lib.FromText
                    , AWS.Lib.Parser
                    , AWS.Lib.Query
                    , AWS.RDS.Internal
@@ -82,12 +82,15 @@
                    , strptime
                    , template-haskell
                    , parallel
+                   , iproute >= 1.2.9
 
 test-suite test
     type:              exitcode-stdio-1.0
     main-is:           Main.hs
     hs-source-dirs:    Tests
-    ghc-options:       -Wall -threaded
+    ghc-options:       -Wall
+                       -threaded
+                       -fno-warn-unused-do-bind
     extensions: OverloadedStrings
     build-depends: base
                  , aws-sdk
@@ -100,6 +103,8 @@
                  , QuickCheck
                  , hspec
                  , HUnit
+                 , lifted-base
+                 , iproute
 
 source-repository head
     type:            git