diff --git a/CMakeLists.txt b/CMakeLists.txt
index 12c511b05..6b6dc9c40 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -341,13 +341,6 @@ function(get_timestamp _var)
     set(${_var} "${timestamp}" PARENT_SCOPE)
 endfunction()
 
-# Prevent boost from linking against libs when building
-add_definitions(-DBOOST_ERROR_CODE_HEADER_ONLY
-    -DBOOST_SYSTEM_NO_LIB
-    -DBOOST_DATE_TIME_NO_LIB
-    -DBOOST_REGEX_NO_LIB
-)
-
 # generate git/build information
 include(GetGitRevisionDescription)
 get_git_head_revision(GIT_REF_SPEC GIT_REV)
@@ -355,17 +348,23 @@ git_describe(GIT_DESC --always --long --dirty)
 git_branch_name(GIT_BRANCH)
 get_timestamp(BUILD_DATE)
 
-if (NOT USE_SYSTEM_BOOST)
-    add_definitions( -DBOOST_ALL_NO_LIB )
+# Boost
+# Prevent boost from linking against libs when building
+add_definitions(-DBOOST_ERROR_CODE_HEADER_ONLY
+    -DBOOST_SYSTEM_NO_LIB
+    -DBOOST_DATE_TIME_NO_LIB
+    -DBOOST_REGEX_NO_LIB
+)
+if (USE_SYSTEM_BOOST)
+    find_package(Boost 1.70.0 COMPONENTS container locale serialization iostreams REQUIRED)
 endif()
 
 enable_testing()
 add_subdirectory(externals)
 
-# Boost
-if (USE_SYSTEM_BOOST)
-    find_package(Boost 1.70.0 COMPONENTS serialization iostreams REQUIRED)
-else()
+# Boost (bundled)
+if (NOT USE_SYSTEM_BOOST)
+    add_definitions( -DBOOST_ALL_NO_LIB )
     add_library(Boost::boost ALIAS boost)
     add_library(Boost::serialization ALIAS boost_serialization)
     add_library(Boost::iostreams ALIAS boost_iostreams)
diff --git a/externals/CMakeLists.txt b/externals/CMakeLists.txt
index 4406c3d66..1927d2ef6 100644
--- a/externals/CMakeLists.txt
+++ b/externals/CMakeLists.txt
@@ -12,27 +12,29 @@ include(DownloadExternals)
 include(ExternalProject)
 
 # Boost
-set(BOOST_ROOT "${CMAKE_SOURCE_DIR}/externals/boost" CACHE STRING "")
-set(Boost_INCLUDE_DIR "${CMAKE_SOURCE_DIR}/externals/boost" CACHE STRING "")
-set(Boost_NO_SYSTEM_PATHS ON CACHE BOOL "")
-add_library(boost INTERFACE)
-target_include_directories(boost SYSTEM INTERFACE ${Boost_INCLUDE_DIR})
+if (NOT USE_SYSTEM_BOOST)
+    message(STATUS "Including vendored Boost library")
+    set(BOOST_ROOT "${CMAKE_SOURCE_DIR}/externals/boost" CACHE STRING "")
+    set(Boost_INCLUDE_DIR "${CMAKE_SOURCE_DIR}/externals/boost" CACHE STRING "")
+    set(Boost_NO_SYSTEM_PATHS ON CACHE BOOL "")
+    add_library(boost INTERFACE)
+    target_include_directories(boost SYSTEM INTERFACE ${Boost_INCLUDE_DIR})
 
-# Boost::serialization
-file(GLOB boost_serialization_SRC "${CMAKE_SOURCE_DIR}/externals/boost/libs/serialization/src/*.cpp")
-add_library(boost_serialization STATIC ${boost_serialization_SRC})
-target_link_libraries(boost_serialization PUBLIC boost)
-
-# Boost::iostreams
-add_library(
-    boost_iostreams
-    STATIC
-    ${CMAKE_SOURCE_DIR}/externals/boost/libs/iostreams/src/file_descriptor.cpp
-    ${CMAKE_SOURCE_DIR}/externals/boost/libs/iostreams/src/mapped_file.cpp
-)
-target_link_libraries(boost_iostreams PUBLIC boost)
+    # Boost::serialization
+    file(GLOB boost_serialization_SRC "${CMAKE_SOURCE_DIR}/externals/boost/libs/serialization/src/*.cpp")
+    add_library(boost_serialization STATIC ${boost_serialization_SRC})
+    target_link_libraries(boost_serialization PUBLIC boost)
 
+    # Boost::iostreams
+    add_library(
+        boost_iostreams
+        STATIC
+        ${CMAKE_SOURCE_DIR}/externals/boost/libs/iostreams/src/file_descriptor.cpp
+        ${CMAKE_SOURCE_DIR}/externals/boost/libs/iostreams/src/mapped_file.cpp
+    )
+    target_link_libraries(boost_iostreams PUBLIC boost)
 # Add additional boost libs here; remember to ALIAS them in the root CMakeLists!
+endif()
 
 # Catch2
 set(CATCH_INSTALL_DOCS OFF CACHE BOOL "")