1 files changed, 2 insertions, 2 deletions

diff --git a/spec/src/Thermoprint/API.hs b/spec/src/Thermoprint/API.hs
index 4f9d074..b27c0b5 100644
--- a/spec/src/Thermoprint/API.hs
+++ b/spec/src/Thermoprint/API.hs
@@ -65,10 +65,10 @@ data PrintingError = UnknownError
 type DraftTitle = Text
 
 instance FromText UTCTime where
-  fromText = parseTimeM True defaultTimeLocale "%s%Q" . T.unpack
+  fromText = parseTimeM True defaultTimeLocale "%F_%T%Q" . T.unpack
 
 instance ToText UTCTime where
-  toText = T.pack . formatTime defaultTimeLocale "%s%Q"
+  toText = T.pack . formatTime defaultTimeLocale "%F_%T%Q"
 
 type ThermoprintAPI = "printers" :> Get '[JSON] (Map PrinterId PrinterStatus)
                       :<|> "jobs" :> (