--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -131,6 +131,11 @@ find_package(Qt6    6.5 REQUIRED COMPONE
 include_directories(${Boost_INCLUDE_DIRS})
 include_directories(${FFTW3_INCLUDE_DIRS})
 
+# Debian: use system libraries
+find_package(PkgConfig)
+pkg_check_modules(EIGEN REQUIRED IMPORTED_TARGET GLOBAL eigen3)
+pkg_check_modules(SQLITE REQUIRED IMPORTED_TARGET GLOBAL sqlite3)
+
 #------------------------------------------------------------------------------#
 # OSX requires an icon file resource.
 #------------------------------------------------------------------------------#
@@ -208,7 +213,6 @@ target_precompile_headers(
 
 target_sources(
   ${TARGET} PRIVATE
-  vendor/sqlite3/sqlite3.c
   JS8_Audio/AudioDevice.cpp
   JS8_Audio/BWFFile.cpp
   JS8_Audio/NotificationAudio.cpp
@@ -308,6 +312,8 @@ target_link_libraries(
   Qt::Network
   Qt::SerialPort
   Qt::Widgets
+  PkgConfig::EIGEN
+  PkgConfig::SQLITE
 )
 
 #------------------------------------------------------------------------------#
--- a/JS8_Main/Flatten.cpp
+++ b/JS8_Main/Flatten.cpp
@@ -6,7 +6,7 @@
 #include <numbers>
 #include <utility>
 #include <vector>
-#include <vendor/Eigen/Dense>
+#include <Eigen/Dense>
 
 // This is an emulation, in spirit at least, of the effect of of the
 // Fortran flat4() subroutine. While our implementation differs from
--- a/JS8_Mode/Detector.h
+++ b/JS8_Mode/Detector.h
@@ -3,7 +3,7 @@
 #include "JS8_Audio/AudioDevice.h"
 #include <QMutex>
 #include <array>
-#include <vendor/Eigen/Dense>
+#include <Eigen/Dense>
 
 // Output device that distributes data in predefined chunks via a signal;
 // underlying device for this abstraction is just the buffer that stores
--- a/JS8_Mode/JS8.cpp
+++ b/JS8_Mode/JS8.cpp
@@ -40,7 +40,7 @@
 #include <unordered_map>
 #include <utility>
 #include <vector>
-#include <vendor/Eigen/Dense>
+#include <Eigen/Dense>
 
 Q_DECLARE_LOGGING_CATEGORY(decoder_js8);
 
--- a/JS8_Main/Inbox.h
+++ b/JS8_Main/Inbox.h
@@ -10,7 +10,7 @@
 #include <QString>
 #include <QVariant>
 
-#include "vendor/sqlite3/sqlite3.h"
+#include "sqlite3.h"
 
 #include "Message.h"
 
