diff --git a/serokell-util.cabal b/serokell-util.cabal
--- a/serokell-util.cabal
+++ b/serokell-util.cabal
@@ -1,5 +1,5 @@
 name:                serokell-util
-version:             0.3.1
+version:             0.4.0
 synopsis:            General-purpose functions by Serokell
 homepage:            https://github.com/serokell/serokell-util
 license:             MIT
diff --git a/src/Serokell/Util/OptParse.hs b/src/Serokell/Util/OptParse.hs
--- a/src/Serokell/Util/OptParse.hs
+++ b/src/Serokell/Util/OptParse.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE MultiParamTypeClasses #-}
+{-# LANGUAGE NoImplicitPrelude     #-}
 
 -- | Some useful helper for optparse-applicative library
 
@@ -9,6 +10,8 @@
        , fromParsec
        ) where
 
+import           Universum
+
 import           Data.String         (IsString (fromString))
 import           Options.Applicative (ArgumentFields, Mod, OptionFields, Parser, ReadM,
                                       argument, eitherReader, option, str)
@@ -26,5 +29,6 @@
 strOption :: IsString s => Mod OptionFields s -> Parser s
 strOption = option fromStr
 
-fromParsec :: Parsec String () a -> ReadM a
-fromParsec parser = eitherReader $ either (Left . show) Right . parse parser "<CLI options>"
+fromParsec :: Parsec Text () a -> ReadM a
+fromParsec parser =
+    eitherReader $ first show . parse parser "<CLI options>" . toText
diff --git a/src/Serokell/Util/Trace.hs b/src/Serokell/Util/Trace.hs
--- a/src/Serokell/Util/Trace.hs
+++ b/src/Serokell/Util/Trace.hs
@@ -31,6 +31,7 @@
 -- Accepts formatter as first parameter, and then multiple arguments to print.
 --
 -- Examples:
+--
 -- >>> traceIdF F.ords 1
 -- 1st
 -- 1