diff --git a/tools/preproc/.gitignore b/tools/preproc/.gitignore
deleted file mode 100755
index eb347087..00000000
--- a/tools/preproc/.gitignore
+++ /dev/null
@@ -1 +0,0 @@
-preproc
diff --git a/tools/preproc/Makefile b/tools/preproc/Makefile
deleted file mode 100755
index 63dedda1..00000000
--- a/tools/preproc/Makefile
+++ /dev/null
@@ -1,20 +0,0 @@
-CXX := g++
-
-CXXFLAGS := -std=c++11 -O2 -Wall -Wno-switch -Werror
-
-SRCS := asm_file.cpp c_file.cpp charmap.cpp preproc.cpp string_parser.cpp \
-	utf8.cpp
-
-HEADERS := asm_file.h c_file.h char_util.h charmap.h preproc.h string_parser.h \
-	utf8.h
-
-.PHONY: all clean
-
-all: preproc
-	@:
-
-preproc: $(SRCS) $(HEADERS)
-	$(CXX) $(CXXFLAGS) $(SRCS) -o $@ $(LDFLAGS)
-
-clean:
-	$(RM) preproc preproc.exe
diff --git a/tools/src/CMakeLists.txt b/tools/src/CMakeLists.txt
index 2f0f141f..5d77a206 100644
--- a/tools/src/CMakeLists.txt
+++ b/tools/src/CMakeLists.txt
@@ -5,3 +5,4 @@ add_subdirectory(bin2c)
 add_subdirectory(gbafix)
 add_subdirectory(gbagfx)
 add_subdirectory(mid2agb)
+add_subdirectory(preproc)
diff --git a/tools/src/preproc/CMakeLists.txt b/tools/src/preproc/CMakeLists.txt
new file mode 100644
index 00000000..f2674fae
--- /dev/null
+++ b/tools/src/preproc/CMakeLists.txt
@@ -0,0 +1,6 @@
+file(GLOB_RECURSE sources *.cpp)
+
+add_executable(preproc ${sources})
+target_include_directories(preproc PRIVATE .)
+
+install(TARGETS preproc RUNTIME DESTINATION bin)
diff --git a/tools/preproc/LICENSE b/tools/src/preproc/LICENSE
similarity index 100%
rename from tools/preproc/LICENSE
rename to tools/src/preproc/LICENSE
diff --git a/tools/preproc/asm_file.cpp b/tools/src/preproc/asm_file.cpp
similarity index 100%
rename from tools/preproc/asm_file.cpp
rename to tools/src/preproc/asm_file.cpp
diff --git a/tools/preproc/asm_file.h b/tools/src/preproc/asm_file.h
similarity index 100%
rename from tools/preproc/asm_file.h
rename to tools/src/preproc/asm_file.h
diff --git a/tools/preproc/c_file.cpp b/tools/src/preproc/c_file.cpp
similarity index 100%
rename from tools/preproc/c_file.cpp
rename to tools/src/preproc/c_file.cpp
diff --git a/tools/preproc/c_file.h b/tools/src/preproc/c_file.h
similarity index 100%
rename from tools/preproc/c_file.h
rename to tools/src/preproc/c_file.h
diff --git a/tools/preproc/char_util.h b/tools/src/preproc/char_util.h
similarity index 100%
rename from tools/preproc/char_util.h
rename to tools/src/preproc/char_util.h
diff --git a/tools/preproc/charmap.cpp b/tools/src/preproc/charmap.cpp
similarity index 100%
rename from tools/preproc/charmap.cpp
rename to tools/src/preproc/charmap.cpp
diff --git a/tools/preproc/charmap.h b/tools/src/preproc/charmap.h
similarity index 100%
rename from tools/preproc/charmap.h
rename to tools/src/preproc/charmap.h
diff --git a/tools/preproc/preproc.cpp b/tools/src/preproc/preproc.cpp
similarity index 100%
rename from tools/preproc/preproc.cpp
rename to tools/src/preproc/preproc.cpp
diff --git a/tools/preproc/preproc.h b/tools/src/preproc/preproc.h
similarity index 100%
rename from tools/preproc/preproc.h
rename to tools/src/preproc/preproc.h
diff --git a/tools/preproc/string_parser.cpp b/tools/src/preproc/string_parser.cpp
similarity index 100%
rename from tools/preproc/string_parser.cpp
rename to tools/src/preproc/string_parser.cpp
diff --git a/tools/preproc/string_parser.h b/tools/src/preproc/string_parser.h
similarity index 100%
rename from tools/preproc/string_parser.h
rename to tools/src/preproc/string_parser.h
diff --git a/tools/preproc/utf8.cpp b/tools/src/preproc/utf8.cpp
similarity index 100%
rename from tools/preproc/utf8.cpp
rename to tools/src/preproc/utf8.cpp
diff --git a/tools/preproc/utf8.h b/tools/src/preproc/utf8.h
similarity index 100%
rename from tools/preproc/utf8.h
rename to tools/src/preproc/utf8.h