diff --git a/Data/X509/Validation.hs b/Data/X509/Validation.hs
--- a/Data/X509/Validation.hs
+++ b/Data/X509/Validation.hs
@@ -39,7 +39,8 @@
 import Data.X509.Validation.Fingerprint
 import Data.X509.Validation.Cache
 import Data.X509.Validation.Types
-import Data.Time.Clock
+import Data.Hourglass
+import System.Hourglass
 import Data.Maybe
 import Data.List
 
@@ -77,7 +78,7 @@
       checkTimeValidity   :: Bool
     -- | The time when the validity check happens. When set to Nothing,
     -- the current time will be used
-    , checkAtTime         :: Maybe UTCTime
+    , checkAtTime         :: Maybe DateTime
     -- | Check that no certificate is included that shouldn't be included.
     -- unfortunately despite the specification violation, a lots of
     -- real world server serves useless and usually old certificates
@@ -120,7 +121,7 @@
     -- of a certificate.
       hookMatchSubjectIssuer :: DistinguishedName -> Certificate -> Bool
     -- | validate that the parametrized time valide with the certificate in argument
-    , hookValidateTime       :: UTCTime -> Certificate -> [FailedReason]
+    , hookValidateTime       :: DateTime -> Certificate -> [FailedReason]
     -- | validate the certificate leaf name with the DNS named used to connect
     , hookValidateName       :: HostName -> Certificate -> [FailedReason]
     -- | user filter to modify the list of failure reasons
@@ -190,7 +191,7 @@
         ValidationCachePass     -> return []
         ValidationCacheDenied s -> return [CacheSaysNo s]
         ValidationCacheUnknown  -> do
-            validationTime <- maybe getCurrentTime return $ checkAtTime checks
+            validationTime <- maybe (timeConvert <$> timeCurrent) return $ checkAtTime checks
             failedReasons <- doValidate validationTime hooks checks store ident cc
             when (null failedReasons) $ (cacheAdd cache) ident fingerPrint (getCertificate top)
             return failedReasons
@@ -198,7 +199,7 @@
 
 
 -- | Validate a certificate chain with explicit parameters
-doValidate :: UTCTime
+doValidate :: DateTime
            -> ValidationHooks
            -> ValidationChecks
            -> CertificateStore
@@ -308,7 +309,7 @@
                 SignatureFailed r -> [InvalidSignature r]
 
 -- | Validate that the current time is between validity bounds
-validateTime :: UTCTime -> Certificate -> [FailedReason]
+validateTime :: DateTime -> Certificate -> [FailedReason]
 validateTime currentTime cert
     | currentTime < before = [InFuture]
     | currentTime > after  = [Expired]
@@ -353,7 +354,7 @@
         wildcardMatch l
             -- <star>.com or <star> is always invalid
             | length l < 2 = [InvalidWildcard]
-            -- some TLD like .uk got small subTLS like (.co.uk), and we don't want to accept *.co.uk
+            -- some TLD like .uk got small subTLD like (.co.uk), and we don't want to accept *.co.uk
             | length (head l) <= 2 && length (head $ drop 1 l) <= 3 && length l < 3 = [InvalidWildcard]
             | l == take (length l) (reverse $ splitDot fqhn) = [] -- success: we got a match
             | otherwise                                      = [NameMismatch fqhn]
diff --git a/x509-validation.cabal b/x509-validation.cabal
--- a/x509-validation.cabal
+++ b/x509-validation.cabal
@@ -1,5 +1,5 @@
 Name:                x509-validation
-Version:             1.5.0
+Version:             1.5.1
 Description:         X.509 Certificate and CRL validation
 License:             BSD3
 License-file:        LICENSE
@@ -23,13 +23,13 @@
                    , directory
                    , filepath
                    , process
-                   , time
+                   , hourglass
                    , data-default-class
                    , pem >= 0.1 && < 0.3
-                   , asn1-types >= 0.2 && < 0.3
-                   , asn1-encoding >= 0.8 && < 0.9
-                   , x509 >= 1.4.7 && < 1.5
-                   , x509-store >= 1.4 && < 1.5
+                   , asn1-types >= 0.3 && < 0.4
+                   , asn1-encoding >= 0.9 && < 0.10
+                   , x509 >= 1.5.0 && < 1.6
+                   , x509-store >= 1.5 && < 1.6
                    , crypto-pubkey >= 0.1.4 && < 0.3
                    , crypto-pubkey-types >= 0.4 && < 0.5
                    , cryptohash >= 0.9 && < 0.12