diff --git a/RNAlien.cabal b/RNAlien.cabal
--- a/RNAlien.cabal
+++ b/RNAlien.cabal
@@ -1,8 +1,5 @@
--- Initial RNAlien.cabal generated by cabal init.  For further documentation, 
--- see http://haskell.org/cabal/users-guide/
-
 name:                RNAlien
-version:             1.2.6
+version:             1.2.8
 synopsis:            Unsupervized construction of RNA family models
 description:         RNAlien is a tool for automatic construction of RNAfamily models from a single sequence.
                      .
@@ -53,8 +50,8 @@
 
 source-repository this
   type:     git
-  location: https://github.com/eggzilla/RNAlien/tree/1.2.6
-  tag:      1.2.6
+  location: https://github.com/eggzilla/RNAlien/tree/1.2.8
+  tag:      1.2.8
                      
 executable RNAlien
   Hs-Source-Dirs:      ./src/Bio/
@@ -89,7 +86,7 @@
 Library
   Hs-Source-Dirs:      ./src/
   ghc-options:         -Wall -O2 -fno-warn-unused-do-bind
-  build-depends:       base >=4.5 && <5, cmdargs, ViennaRNAParser>=1.3.1, process, directory, blastxml>=0.3.2, biofasta, parsec, random, BlastHTTP>=1.2.1, biocore, bytestring, Taxonomy >= 1.0.2, either-unwrap, containers, ClustalParser>=1.1.0, EntrezHTTP>=1.0.3, vector, edit-distance, cassava, matrix, hierarchical-clustering, filepath, HTTP, http-conduit, hxt, network, aeson, text, transformers, pureMD5
+  build-depends:       base >=4.5 && <5, cmdargs, ViennaRNAParser>=1.3.1, process, directory, blastxml>=0.3.2, biofasta, parsec, random, BlastHTTP>=1.2.1, biocore, bytestring, Taxonomy >= 1.0.2, either-unwrap, containers, ClustalParser>=1.1.0, EntrezHTTP>=1.0.3, vector, edit-distance, cassava, matrix, hierarchical-clustering, filepath, HTTP, http-conduit, hxt, network, aeson, text, transformers, pureMD5, http-types
   Exposed-Modules:     Bio.RNAlienData
                        Bio.RNAlienLibrary
                        Bio.RNAcentralHTTP
diff --git a/src/Bio/RNAcentralHTTP.hs b/src/Bio/RNAcentralHTTP.hs
--- a/src/Bio/RNAcentralHTTP.hs
+++ b/src/Bio/RNAcentralHTTP.hs
@@ -9,8 +9,8 @@
                       buildStringViaMD5Query,                        
                       getRNACentralEntries,
                       showRNAcentralAlienEvaluation,
-                      RNAcentralEntryResponse,
-                      RNAcentralEntry
+                      RNAcentralEntryResponse(..),
+                      RNAcentralEntry(..)
                       ) where
 
 import Network.HTTP.Conduit    
@@ -24,7 +24,6 @@
 import Bio.Core.Sequence 
 import Bio.Sequence.Fasta
 import Data.Either
-import Data.Aeson.Types
 
 --Datatypes
 -- | Data structure for RNAcentral entry response
diff --git a/src/Bio/RNAcentralHTTPRequest.hs b/src/Bio/RNAcentralHTTPRequest.hs
--- a/src/Bio/RNAcentralHTTPRequest.hs
+++ b/src/Bio/RNAcentralHTTPRequest.hs
@@ -6,8 +6,6 @@
 module Main where
     
 import System.Console.CmdArgs    
-import Bio.RNAlienLibrary
-import Data.Either.Unwrap
 import Bio.RNAcentralHTTP
 
 data Options = Options            
diff --git a/src/Bio/RNAlien.hs b/src/Bio/RNAlien.hs
--- a/src/Bio/RNAlien.hs
+++ b/src/Bio/RNAlien.hs
@@ -33,7 +33,8 @@
     inputQueryNumber :: Int,
     threads :: Int,
     taxonomyRestriction :: Maybe String,
-    sessionIdentificator :: Maybe String
+    sessionIdentificator :: Maybe String,
+    performEvaluation :: Bool
   } deriving (Show,Data,Typeable)
 
 options :: Options
@@ -52,8 +53,9 @@
     inputQueryNumber = (5 :: Int) &= name "n" &= help "Number of queries used for candidate search. Default: 5",
     threads = 1 &= name "c" &= help "Number of available cpu slots/cores. Default: 1",
     taxonomyRestriction = Nothing &= name "r" &= help "Restrict search space to taxonomic kingdom (bacteria,archea,eukaryia). Default: not set",
-    sessionIdentificator = Nothing &= name "d" &= help "Optional session id that is used instead of automatically generated one."
-  } &= summary ("RNAlien " ++ alienVersion) &= help "Florian Eggenhofer, Ivo L. Hofacker, Christian Höner zu Siederdissen - 2013 - 2016" &= verbosity       
+    sessionIdentificator = Nothing &= name "d" &= help "Optional session id that is used instead of automatically generated one.",
+    performEvaluation = True &= name "x" &= help "Perform evaluation step. Default: True"
+  } &= summary ("RNAlien " ++ alienVersion) &= help "Florian Eggenhofer, Ivo L. Hofacker, Christian Höner zu Siederdissen - 2013 - 2017" &= verbosity       
                 
 main :: IO ()
 main = do
@@ -100,11 +102,16 @@
               logMessage (show initialization) temporaryDirectoryPath
               modelConstructionResults <- modelConstructer staticOptions initialization
               let resultTaxonomyRecordsCSVTable = constructTaxonomyRecordsCSVTable modelConstructionResults
-              resultEvaluation <- evaluateConstructionResult staticOptions modelConstructionResults
-              appendFile (temporaryDirectoryPath ++ "Log") resultEvaluation
               writeFile (temporaryDirectoryPath ++ "result.csv") resultTaxonomyRecordsCSVTable
-              resultSummary modelConstructionResults staticOptions
-              writeFile (temporaryDirectoryPath ++ "done") ""
+              if performEvaluation
+                then do
+                  resultEvaluation <- evaluateConstructionResult staticOptions modelConstructionResults
+                  appendFile (temporaryDirectoryPath ++ "Log") resultEvaluation
+                  resultSummary modelConstructionResults staticOptions
+                  writeFile (temporaryDirectoryPath ++ "done") ""
+                else do
+                  resultSummary modelConstructionResults staticOptions
+                  writeFile (temporaryDirectoryPath ++ "done") ""
 
 alienVersion :: String
 alienVersion = showVersion version
diff --git a/src/Bio/RNAlienLibrary.hs b/src/Bio/RNAlienLibrary.hs
--- a/src/Bio/RNAlienLibrary.hs
+++ b/src/Bio/RNAlienLibrary.hs
@@ -43,6 +43,7 @@
 import Data.Int (Int16)
 import Bio.RNAlienData
 import qualified Data.ByteString.Lazy.Char8 as L
+import qualified Data.ByteString.Char8 as B
 import Bio.Taxonomy 
 import Data.Either.Unwrap
 import Data.Maybe
@@ -63,9 +64,10 @@
 import Bio.RNAfoldParser
 import Bio.RNAalifoldParser
 import Bio.RNAzParser
-import Network.HTTP
+import qualified Network.HTTP.Conduit as N
+import Network.HTTP.Types.Status
 import qualified Bio.RNAcodeParser as RC
-import Bio.RNAcentralHTTP
+import qualified Bio.RNAcentralHTTP as RCH
 import Bio.InfernalParser
 import qualified Data.Text as T
 import qualified Data.Text.IO as TI
@@ -1509,9 +1511,9 @@
   let cmFilepath = tempDirPath staticOptions ++ "result.cm"
   let resultSequences = (inputFasta mCResult):map nucleotideSequence (concatMap sequenceRecords (taxRecords mCResult))
   let resultNumber = length resultSequences + 1 
-  let rnaCentralQueries = map buildSequenceViaMD5Query resultSequences    
-  rnaCentralEntries <- getRNACentralEntries rnaCentralQueries
-  let rnaCentralEvaluationResult = showRNAcentralAlienEvaluation rnaCentralEntries
+  let rnaCentralQueries = map RCH.buildSequenceViaMD5Query resultSequences    
+  rnaCentralEntries <- RCH.getRNACentralEntries rnaCentralQueries
+  let rnaCentralEvaluationResult = RCH.showRNAcentralAlienEvaluation rnaCentralEntries
   writeFile (tempDirPath staticOptions ++ "result.rnacentral") rnaCentralEvaluationResult
   systemCMalign ("--outformat=Clustal --cpu " ++ show (cpuThreads staticOptions)) cmFilepath fastaFilepath clustalFilepath
   let resultModelStatistics = tempDirPath staticOptions ++ "result.cmstat"
@@ -1652,14 +1654,13 @@
 -- | Check if alien can connect to NCBI
 checkNCBIConnection :: IO (Either String String)
 checkNCBIConnection = do
-   response <- simpleHTTP (getRequest "https://www.ncbi.nlm.nih.gov")
-   if isRight response
-     then do
-       let rightResponse = fromRight response
-       if rspCode rightResponse == (2,0,0)
-         then return (Right ("Network connection with NCBI server is ok: "  ++ show (rspCode rightResponse)))
-         else return (Left ("Could not connect to NCBI server \"https://www.ncbi.nlm.nih.gov\". Response Code: " ++ show (rspCode rightResponse)))
-     else return (Left ("Could not connect to NCBI server: \"https://www.ncbi.nlm.nih.gov\": " ++ show (fromLeft response)))
+   req <- N.parseRequest "https://www.ncbi.nlm.nih.gov"
+   manager <- N.newManager N.tlsManagerSettings
+   response <- N.httpLbs req manager
+   let sta = N.responseStatus response
+   if statusIsSuccessful sta
+     then return (Right ("Network connection with NCBI server was successful"))
+     else return (Left ("Could not connect to NCBI server \"https://www.ncbi.nlm.nih.gov\". Response Code: " ++ show (statusCode sta) ++ " \n" ++ B.unpack (statusMessage sta)))
 
 -- | Blast evalue is set stricter in inital alignment mode
 setBlastExpectThreshold :: ModelConstruction -> Double
