diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4540de0b..27a2db55 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -336,6 +336,7 @@ add_custom_command(OUTPUT ${STA_TCL_INIT}
 # Do not use REQUIRED because it also requires TK, which is not used by OpenSTA.
 find_package(TCL)
 
+# Referenced by util/StaConfig.hh.cmake
 set(TCL_READLINE 0)
 # check for tclReadline
 if (USE_TCL_READLINE)
@@ -352,13 +353,19 @@ if (USE_TCL_READLINE)
     )
   if (TCL_READLINE_LIBRARY)
     message(STATUS "TCL readline library: ${TCL_READLINE_LIBRARY}")
-    # Referenced by StaConfig.hh.cmake
-    set(TCL_READLINE 1)
+  else()
+    message(STATUS "TCL readline library: NOT FOUND")
   endif()
 
   find_path(TCL_READLINE_INCLUDE tclreadline.h)
   if (TCL_READLINE_INCLUDE)
     message(STATUS "TCL readline header: ${TCL_READLINE_INCLUDE}/tclreadline.h")
+  else()
+    message(STATUS "TCL readline header: NOT FOUND")
+  endif()
+
+  if (TCL_READLINE_LIBRARY AND TCL_READLINE_INCLUDE)
+    set(TCL_READLINE 1)
   endif()
 endif()
 
@@ -515,21 +522,14 @@ target_link_libraries(OpenSTA
   ${CUDD_LIB}
   )
 
-if (TCL_READLINE_LIBRARY)
-  target_link_libraries(OpenSTA ${TCL_READLINE_LIBRARY})
-endif()
-
 if (ZLIB_LIBRARIES)
   target_link_libraries(OpenSTA ${ZLIB_LIBRARIES})
 endif()
 
-target_link_libraries(OpenSTA )
-
 target_include_directories(OpenSTA
   PUBLIC
   include
   ${TCL_INCLUDE_PATH}
-  ${TCL_READLINE_INCLUDE}
 
   PRIVATE
   include/sta
@@ -537,6 +537,13 @@ target_include_directories(OpenSTA
   ${CUDD_INCLUDE}
   )
 
+if (TCL_READLINE)
+  target_link_libraries(OpenSTA ${TCL_READLINE_LIBRARY})
+  target_include_directories(OpenSTA
+    PUBLIC
+    ${TCL_READLINE_INCLUDE})
+endif()
+
 # common to gcc/clang
 set(CXX_FLAGS -Wall -Wextra -pedantic -Wcast-qual -Wredundant-decls -Wformat-security)
 
diff --git a/Dockerfile.ubuntu_18.04 b/Dockerfile.ubuntu_18.04
index 82ee3ef0..7d0c5647 100644
--- a/Dockerfile.ubuntu_18.04
+++ b/Dockerfile.ubuntu_18.04
@@ -2,31 +2,32 @@ FROM ubuntu:18.04
 LABEL author="James Cherry"
 LABEL maintainer="James Cherry <cherry@parallaxsw.com>"
 
-# install basics
+# Install basics
 ARG DEBIAN_FRONTEND=noninteractive
 RUN apt-get update && \
-    apt-get install -y wget apt-utils git cmake gcc tcl-dev swig bison flex
+    apt-get install -y wget cmake gcc tcl-dev tcl-tclreadline libeigen3-dev swig bison flex
 
-# download CUDD
-RUN wget https://www.davidkebo.com/source/cudd_versions/cudd-3.0.0.tar.gz && \
+# Download CUDD
+RUN wget https://raw.githubusercontent.com/davidkebo/cudd/main/cudd_versions/cudd-3.0.0.tar.gz && \
     tar -xvf cudd-3.0.0.tar.gz && \
     rm cudd-3.0.0.tar.gz
 
-# install CUDD
+# Install CUDD
 RUN cd cudd-3.0.0 && \
     mkdir ../cudd && \
-    ./configure --prefix=$HOME/cudd && \
-    make && \
+    ./configure && \
+    make -j`nproc` && \
     make install
 
-# copy files and install OpenSTA
+# Copy files and install OpenSTA
 RUN mkdir OpenSTA
 COPY . OpenSTA
 RUN cd OpenSTA && \
+    rm -rf build && \
     mkdir build && \
     cd build && \
-    cmake .. -DCUDD=$HOME/cudd && \
-    make
+    cmake .. && \
+    make -j`nproc`
 
 # Run sta on entry
 ENTRYPOINT ["OpenSTA/app/sta"]
diff --git a/app/Main.cc b/app/Main.cc
index 596eb222..1f417333 100644
--- a/app/Main.cc
+++ b/app/Main.cc
@@ -19,7 +19,6 @@
 
 #include <stdio.h>
 #include <cstdlib>              // exit
-#include <filesystem>
 #include <tcl.h>
 #if TCL_READLINE
   #include <tclreadline.h>