diff --git a/src/main/kotlin/terminal/TerminalConfiguration.kt b/src/main/kotlin/terminal/TerminalConfiguration.kt
index b43a22e..d3b88a3 100644
--- a/src/main/kotlin/terminal/TerminalConfiguration.kt
+++ b/src/main/kotlin/terminal/TerminalConfiguration.kt
@@ -9,15 +9,11 @@ import java.io.PipedOutputStream
 
 class TerminalConfiguration {
 
-    var inputWriter: PipedOutputStream? = null
-        private set
+    lateinit var inputWriter: PipedOutputStream
     lateinit var inputReader: PipedInputStream
-        private set
-    var outputWriter: PipedOutputStream? = null
-        private set
-    var outputReader: PipedInputStream? = null
-        private set
-    var terminal: IOSafeTerminal? = null
+    lateinit var outputWriter: PipedOutputStream
+    lateinit var outputReader: PipedInputStream
+    lateinit var terminal: IOSafeTerminal
 
     fun setInputPair(inputWriter: PipedOutputStream, inputReader: PipedInputStream) {
         this.inputWriter = inputWriter
@@ -27,7 +23,7 @@ class TerminalConfiguration {
 
     private fun connectInputPair() {
         try {
-            inputWriter!!.connect(inputReader!!)
+            inputWriter.connect(inputReader)
         } catch (e: IOException) {
             throw LispIOException(e)
         }
@@ -41,7 +37,7 @@ class TerminalConfiguration {
 
     private fun connectOutputPair() {
         try {
-            outputWriter!!.connect(outputReader!!)
+            outputWriter.connect(outputReader)
         } catch (e: IOException) {
             throw LispIOException(e)
         }