diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 168163ee2..c0acfa9b5 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -45,6 +45,7 @@ jobs:
 
       - name: Build testproject
         run: |
+          set PATH=%PATH%;"C:/Program Files/Microsoft Visual Studio/2022/Enterprise/VC/Tools/MSVC/14.40.33807/bin/Hostx64/x64"
           cd resources/testproject
           ..\..\build\${{ matrix.build_type }}\c3c.exe --debug-log --emit-llvm run hello_world_win32
           dir build\llvm_ir
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4f7a37822..894de8500 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -244,6 +244,7 @@ add_executable(c3c
         src/build/builder.c
         src/build/build_options.c
         src/build/project_creation.c
+        src/build/libraries.c
         src/compiler/ast.c
         src/compiler/bigint.c
         src/compiler/codegen_general.c
@@ -256,7 +257,6 @@ add_executable(c3c
         src/compiler/headers.c
         src/compiler/json_output.c
         src/compiler/lexer.c
-        src/compiler/libraries.c
         src/compiler/linker.c
         src/compiler/llvm_codegen.c
         src/compiler/abi/c_abi_aarch64.c
@@ -325,7 +325,8 @@ add_executable(c3c
         src/compiler/expr.c
         src/utils/time.c
         src/utils/http.c
-        src/compiler/sema_liveness.c)
+        src/compiler/sema_liveness.c
+        src/build/common_build.c)
 
 
 if (C3_USE_TB)
diff --git a/releasenotes.md b/releasenotes.md
index 306f0d554..a76042666 100644
--- a/releasenotes.md
+++ b/releasenotes.md
@@ -13,6 +13,7 @@
 - Updated mangling.
 - Added `$$unaligned_load` and `$$unaligned_store`.
 - `--no-headers` option to suppress creating headers when generating a library.
+- Support c-file compilation in libraries.
 
 ### Fixes
 - Error with unsigned compare in `@ensure` when early returning 0 #1207.
diff --git a/resources/testproject/hello_world.c3 b/resources/testproject/hello_world.c3
index 0909b0113..97c720056 100644
--- a/resources/testproject/hello_world.c3
+++ b/resources/testproject/hello_world.c3
@@ -1,6 +1,7 @@
 module hello_world;
 import std;
 import bar;
+import clib;
 
 fn int test_doubler(int x) @if(env::WIN32) => x * x;
 extern fn int test_doubler(int) @if(!env::WIN32);
@@ -12,6 +13,6 @@ fn int main()
     bar::test();
     printf("Hello double: %d\n", test_doubler(11));
 	if ($feature(ABCD)) io::printn("ABCD");
-
+	clib::hello_from_c();
     return 0;
 }
\ No newline at end of file
diff --git a/resources/testproject/lib/clib.c3l/clib.c3i b/resources/testproject/lib/clib.c3l/clib.c3i
new file mode 100644
index 000000000..dee7235d9
--- /dev/null
+++ b/resources/testproject/lib/clib.c3l/clib.c3i
@@ -0,0 +1,3 @@
+module clib;
+
+extern fn void hello_from_c();
diff --git a/resources/testproject/lib/clib.c3l/hello.c b/resources/testproject/lib/clib.c3l/hello.c
new file mode 100644
index 000000000..85c7216b1
--- /dev/null
+++ b/resources/testproject/lib/clib.c3l/hello.c
@@ -0,0 +1,5 @@
+#include <stdio.h>
+void hello_from_c(void)
+{
+	puts("Hello from C!");
+}
\ No newline at end of file
diff --git a/resources/testproject/lib/clib.c3l/manifest.json b/resources/testproject/lib/clib.c3l/manifest.json
new file mode 100644
index 000000000..8169c6505
--- /dev/null
+++ b/resources/testproject/lib/clib.c3l/manifest.json
@@ -0,0 +1,13 @@
+{ 
+  "provides" : "clib",
+  "c-sources" : ["hello.c"],
+  "targets" : {
+    "macos-x64" : {
+    },
+    "macos-aarch64" : {},
+    "linux-x64" : {
+      "c-flags-override": "-fPIE"
+    },
+	"windows-x64" : { }
+  }
+}
diff --git a/resources/testproject/project.json b/resources/testproject/project.json
index 68e21e6e3..9698f7010 100644
--- a/resources/testproject/project.json
+++ b/resources/testproject/project.json
@@ -11,23 +11,23 @@
   "sources": [
     "./**"
   ],
-  // libraries to use
-  "dependencies": [],
+  "dependency-search-paths": [ "./lib" ],
+  "dependencies": ["clib"],
 
   "features": ["ABCD"],
 
-  // c compiler
-  "cc": "cc",
   // c sources
   "targets": {
     "hello_world": {
       "type": "executable",
       "c-sources-override": [
         "./csource/**"
-      ]
+      ],
+      "reloc": "PIE",
     },
     "hello_world_win32": {
       "type": "executable",
+      "cc" : "cl.exe",
       "c-sources-override": [
       ]
     },
diff --git a/src/build/build.h b/src/build/build.h
index 75a34040b..a5f1b8765 100644
--- a/src/build/build.h
+++ b/src/build/build.h
@@ -419,19 +419,27 @@ typedef enum
 
 typedef struct
 {
+	struct Library__ *parent;
 	ArchOsTarget arch_os;
+	const char *cc;
+	const char *cflags;
+	const char **csource_dirs;
+	const char **csources;
 	const char **execs;
 	const char **link_flags;
 	const char **linked_libs;
 	const char **depends;
 } LibraryTarget;
 
-typedef struct
+typedef struct Library__
 {
 	const char *dir;
 	const char *provides;
 	const char **depends;
 	const char **execs;
+	const char *cc;
+	const char *cflags;
+	const char **csource_dirs;
 	LibraryTarget *target_used;
 	LibraryTarget **targets;
 } Library;
@@ -441,6 +449,7 @@ typedef struct
 {
 	TargetType type;
 	Library **library_list;
+	LibraryTarget **ccompling_libraries;
 	const char *name;
 	const char *version;
 	const char *langrev;
@@ -501,9 +510,9 @@ typedef struct
 	const char *testfn;
 	const char *cc;
 	const char *cflags;
-	const char **exec;
 	const char **csource_dirs;
 	const char **csources;
+	const char **exec;
 	const char **feature_list;
 	const char *custom_linker_path;
 	struct
@@ -566,7 +575,7 @@ static BuildTarget default_build_target = {
 		.strip_unused = STRIP_UNUSED_NOT_SET,
 		.symtab_size = DEFAULT_SYMTAB_SIZE,
 		.reloc_model = RELOC_DEFAULT,
-		.cc = "cc",
+		.cc = NULL,
 		.version = "1.0.0",
 		.langrev = "1",
 		.cpu = "generic",
@@ -591,3 +600,4 @@ bool command_accepts_files(CompilerCommand command);
 void update_build_target_with_opt_level(BuildTarget *target, OptimizationSetting level);
 void create_project(BuildOptions *build_options);
 void create_library(BuildOptions *build_options);
+void resolve_libraries(BuildTarget *build_target);
\ No newline at end of file
diff --git a/src/build/build_internal.h b/src/build/build_internal.h
index 6e51b992c..7e142bd70 100644
--- a/src/build/build_internal.h
+++ b/src/build/build_internal.h
@@ -12,6 +12,8 @@ typedef struct
 	BuildTarget **targets;
 } Project;
 
+extern const char *trust_level[3];
+
 static const char *memory_environment[6] = {
 	[MEMORY_ENV_NORMAL] = "normal",
 	[MEMORY_ENV_SMALL] = "small",
@@ -85,3 +87,15 @@ static const char *reloc_models[5] = {
 Project *project_load(void);
 BuildTarget *project_select_target(Project *project, const char *optional_target);
 void update_feature_flags(const char ***flags, const char ***removed_flag, const char *arg, bool add);
+
+const char *get_string(const char *file, const char *category, JSONObject *table, const char *key,
+                       const char *default_value);
+int get_valid_bool(const char *file, const char *target, JSONObject *json, const char *key, int default_val);
+const char *get_optional_string(const char *file, const char *category, JSONObject *table, const char *key);
+const char *get_mandatory_string(const char *file, const char *category, JSONObject *object, const char *key);
+const char **get_string_array(const char *file, const char *category, JSONObject *table, const char *key, bool mandatory);
+const char **get_optional_string_array(const char *file, const char *target, JSONObject *table, const char *key);
+const char *get_cflags(const char *file, const char *target, JSONObject *json, const char *original_flags);
+void get_list_append_strings(const char *file, const char *target, JSONObject *json, const char ***list_ptr,
+                             const char *base, const char *override, const char *add);
+int get_valid_string_setting(const char *file, const char *target, JSONObject *json, const char *key, const char** values, int first_result, int count, const char *expected);
diff --git a/src/build/common_build.c b/src/build/common_build.c
new file mode 100644
index 000000000..aac546a7e
--- /dev/null
+++ b/src/build/common_build.c
@@ -0,0 +1,135 @@
+#include "build_internal.h"
+#include "utils/common.h"
+
+const char *get_optional_string(const char *file, const char *category, JSONObject *table, const char *key)
+{
+	JSONObject *value = json_obj_get(table, key);
+	if (!value) return NULL;
+	if (value->type != J_STRING)
+	{
+		if (category) error_exit("In file '%s': '%s' had an invalid '%s' field that was not a string, please correct it.", file, category, key);
+		error_exit("File '%s' had an invalid '%s' field that was not a string, please correct it.", file, category, key);
+	}
+	return value->str;
+}
+
+const char *get_mandatory_string(const char *file, const char *category, JSONObject *object, const char *key)
+{
+	const char *value = get_optional_string(file, category, object, key);
+	if (!value)
+	{
+		if (category) error_exit("In file '%s': The mandatory field '%s' was missing in '%s'.", file, key, category);
+		error_exit("In file '%s': The mandatory field '%s' was missing.", file);
+	}
+	return value;
+}
+
+const char *get_string(const char *file, const char *category, JSONObject *table, const char *key,
+                       const char *default_value)
+{
+	const char *value = get_optional_string(file, category, table, key);
+	return value ? value : default_value;
+}
+
+
+int get_valid_bool(const char *file, const char *target, JSONObject *json, const char *key, int default_val)
+{
+	JSONObject *value = json_obj_get(json, key);
+	if (!value) return default_val;
+	if (value->type != J_BOOL)
+	{
+		if (target) error_exit("In file '%s': '%s' had an invalid '%s' field that was not a boolean, please correct it.", file, target, key);
+		error_exit("In file '%s': An invalid '%s' field that was not a boolean, please correct it.", file, target, key);
+	}
+	return value->b;
+}
+
+const char **get_string_array(const char *file, const char *category, JSONObject *table, const char *key, bool mandatory)
+{
+	JSONObject *value = json_obj_get(table, key);
+	if (!value)
+	{
+		if (mandatory)
+		{
+			if (category) error_exit("In file '%s': '%s' was missing a mandatory '%s' field, please add it.", file, category, key);
+			error_exit("In file '%s': mandatory '%s' field is missing, please add it.", file, key);
+		}
+		return NULL;
+	}
+	if (value->type != J_ARRAY) goto NOT_ARRAY;
+	const char **values = NULL;
+	for (unsigned i = 0; i < value->array_len; i++)
+	{
+		JSONObject *val = value->elements[i];
+		if (val->type != J_STRING) goto NOT_ARRAY;
+		vec_add(values, val->str);
+	}
+	return values;
+NOT_ARRAY:
+	if (category) error_exit("In file '%s': '%s' had an invalid mandatory '%s' field that was not a string array, please correct it", file, category, key);
+	error_exit("In file '%s': mandatory '%s' field that was not a string array, please correct it.", file, key);
+}
+
+const char **get_optional_string_array(const char *file, const char *target, JSONObject *table, const char *key)
+{
+	return get_string_array(file, target, table, key, false);
+}
+
+const char *get_cflags(const char *file, const char *target, JSONObject *json, const char *original_flags)
+{
+	// CFlags
+	const char *cflags = get_optional_string(file, target, json, target ? "cflags-override" : "cflags");
+	const char *cflags_add = target ? get_optional_string(file, target, json, "cflags-add") : NULL;
+	if (cflags && cflags_add)
+	{
+		error_exit("In file '%s': '%s' is combining both 'cflags-add' and 'cflags-override', only one may be used.", file, target);
+	}
+	if (cflags) original_flags = cflags;
+	if (!cflags_add) return original_flags;
+	if (original_flags)
+	{
+		return str_printf("%s %s", original_flags, cflags_add);
+	}
+	return cflags_add;
+}
+
+INLINE void append_strings_to_strings(const char*** list_of_strings_ptr, const char **strings_to_append)
+{
+	FOREACH(const char *, string, strings_to_append) vec_add(*list_of_strings_ptr, string);
+}
+
+void get_list_append_strings(const char *file, const char *target, JSONObject *json, const char ***list_ptr,
+                             const char *base, const char *override, const char *add)
+{
+	const char **value = get_optional_string_array(file, target, json, target ? override : base);
+	const char **add_value = target ? get_optional_string_array(file, target, json, add) : NULL;
+	if (value && add_value)
+	{
+		error_exit("In file '%s': '%s' is combining both '%s' and '%s', only one may be used.", file, target, override, add);
+	}
+	if (value) *list_ptr = value;
+	if (add_value)
+	{
+		append_strings_to_strings(&add_value, *list_ptr);
+		*list_ptr = add_value;
+	}
+}
+
+int get_valid_string_setting(const char *file, const char *target, JSONObject *json, const char *key, const char** values, int first_result, int count, const char *expected)
+{
+	JSONObject *value = json_obj_get(json, key);
+	if (!value)
+	{
+		return -1;
+	}
+	if (value->type == J_STRING)
+	{
+		int res = str_findlist(value->str, count, values);
+		if (res >= 0) return res + first_result;
+	}
+	if (target)
+	{
+		error_exit("In file '%s': '%s' had an invalid value for '%s', expected %s", file, target, key, expected);
+	}
+	error_exit("In file '%s': Invalid value for '%s', expected %s", file, key, expected);
+}
diff --git a/src/compiler/libraries.c b/src/build/libraries.c
similarity index 61%
rename from src/compiler/libraries.c
rename to src/build/libraries.c
index 21004bdd3..cdf638bb1 100644
--- a/src/compiler/libraries.c
+++ b/src/build/libraries.c
@@ -1,49 +1,10 @@
-#include "compiler_internal.h"
-#include "../utils/json.h"
+#include "build_internal.h"
+#include "compiler/compiler.h"
 
 #define MANIFEST_FILE "manifest.json"
 
-static inline void parse_library_target(Library *library, LibraryTarget *target, JSONObject *object);
-
-static inline JSONObject *get_mandatory(Library *library, JSONObject *object, const char *key)
-{
-	JSONObject *value = json_obj_get(object, key);
-	if (!value) error_exit("The mandatory '%s' field was missing in '%s'.", library->dir);
-	return value;
-}
-
-static inline const char *get_mandatory_string(Library *library, JSONObject *object, const char *key)
-{
-	JSONObject *value = get_mandatory(library, object, key);
-	if (value->type != J_STRING) error_exit("Expected string value for '%s' in '%s'.", library->dir);
-	return value->str;
-}
-
-static inline JSONObject *get_optional_string_array(Library *library, JSONObject *object, const char *key)
-{
-	JSONObject *value = json_obj_get(object, key);
-	if (!value) return NULL;
-	if (value->type != J_ARRAY) error_exit("Expected an array value for '%s' in '%s'.", library->dir);
-	for (int i = 0; i < value->array_len; i++)
-	{
-		JSONObject *val = value->elements[i];
-		if (val->type != J_STRING) error_exit("Expected only strings in array '%s' in '%s'.", library->dir);
-	}
-	return value;
-}
-
-static inline const char **get_optional_string_array_as_array(Library *library, JSONObject *object, const char *key)
-{
-	JSONObject *array = get_optional_string_array(library, object, key);
-	if (!array || !array->array_len) return NULL;
-	const char **array_result = VECNEW(const char*, array->array_len);
-	for (size_t i = 0; i < array->array_len; i++)
-	{
-		vec_add(array_result, array->elements[i]->str);
-	}
-	return array_result;
-}
-
+static inline void parse_library_target(Library *library, LibraryTarget *target, const char *target_name,
+                                        JSONObject *object);
 
 static inline void parse_library_type(Library *library, LibraryTarget ***target_group, JSONObject *object)
 {
@@ -55,6 +16,7 @@ static inline void parse_library_type(Library *library, LibraryTarget ***target_
 		const char *key = object->keys[i];
 		if (member->type != J_OBJECT) error_exit("Expected a list of properties for a target in %s.", library->dir);
 		LibraryTarget *library_target = CALLOCS(LibraryTarget);
+		library_target->parent = library;
 		ArchOsTarget target = arch_os_target_from_string(key);
 		if (target == ARCH_OS_TARGET_DEFAULT)
 		{
@@ -62,39 +24,45 @@ static inline void parse_library_type(Library *library, LibraryTarget ***target_
 		}
 		library_target->arch_os = target;
 		vec_add(*target_group, library_target);
-		parse_library_target(library, library_target, member);
+		parse_library_target(library, library_target, key, member);
 	}
 }
 
-static inline void parse_library_target(Library *library, LibraryTarget *target, JSONObject *object)
+static inline void parse_library_target(Library *library, LibraryTarget *target, const char *target_name,
+                                        JSONObject *object)
 {
-	target->link_flags = get_optional_string_array_as_array(library, object, "linkflags");
-	target->linked_libs = get_optional_string_array_as_array(library, object, "linked-libs");
-	target->depends = get_optional_string_array_as_array(library, object, "depends");
-	target->execs = get_optional_string_array_as_array(library, object, "execs");
+	target->link_flags = get_string_array(library->dir, target_name, object, "linkflags", false);
+	target->linked_libs = get_string_array(library->dir, target_name, object, "linked-libs", false);
+	target->depends = get_string_array(library->dir, target_name, object, "depends", false);
+	target->execs = get_string_array(library->dir, target_name, object, "execs", false);
+	target->cc = get_string(library->dir, target_name, object, "cc", library->cc);
+	target->cflags = get_cflags(library->dir, target_name, object, library->cflags);
+	target->csource_dirs = library->csource_dirs;
+	get_list_append_strings(library->dir, target_name, object, &target->csource_dirs, "c-sources", "c-sources-override", "c-sources-add");
 }
 
 static Library *add_library(JSONObject *object, const char *dir)
 {
 	Library *library = CALLOCS(Library);
 	library->dir = dir;
-	const char *provides = get_mandatory_string(library, object, "provides");
+	const char *provides = get_mandatory_string(dir, NULL, object, "provides");
+	DEBUG_LOG("Added library %s", provides);
 	if (!str_is_valid_lowercase_name(provides))
 	{
 		char *res = strdup(provides);
 		str_ellide_in_place(res, 32);
-		error_exit("Invalid 'provides' module name in %s, was '%s'.", library->dir,
-		           json_obj_get(object, "provides")->str);
+		error_exit("Invalid 'provides' module name in %s, was '%s'.", library->dir, res);
 	}
 	library->provides = provides;
-	library->execs = get_optional_string_array_as_array(library, object, "execs");
-	library->depends = get_optional_string_array_as_array(library, object, "depends");
+	library->execs = get_optional_string_array(library->dir, NULL, object, "execs");
+	library->depends = get_optional_string_array(library->dir, NULL, object, "depends");
+	library->cc = get_optional_string(dir, NULL, object, "cc");
+	library->cflags = get_cflags(library->dir, NULL, object, NULL);
+	get_list_append_strings(library->dir, NULL, object, &library->csource_dirs, "c-sources", "c-sources-override", "c-sources-add");
 	parse_library_type(library, &library->targets, json_obj_get(object, "targets"));
 	return library;
 }
 
-
-
 static Library *find_library(Library **libs, size_t lib_count, const char *name)
 {
 	for (size_t i = 0; i < lib_count; i++)
@@ -104,13 +72,13 @@ static Library *find_library(Library **libs, size_t lib_count, const char *name)
 	error_exit("Required library '%s' could not be found. You can add additional library search paths using '--libdir' in case you forgot one.", name);
 }
 
-static void add_library_dependency(Library *library, Library **library_list, size_t lib_count)
+static void add_library_dependency(BuildTarget *build_target, Library *library, Library **library_list, size_t lib_count)
 {
 	if (library->target_used) return;
 	LibraryTarget *target_found = NULL;
 	FOREACH(LibraryTarget *, target, library->targets)
 	{
-		if (target->arch_os == active_target.arch_os_target)
+		if (target->arch_os == build_target->arch_os_target)
 		{
 			target_found = target;
 			break;
@@ -118,16 +86,17 @@ static void add_library_dependency(Library *library, Library **library_list, siz
 	}
 	if (!target_found)
 	{
-		error_exit("Library '%s' cannot be used with arch/os '%s'.", library->provides, arch_os_target[active_target.arch_os_target]);
+		error_exit("Library '%s' cannot be used with arch/os '%s'.", library->provides, arch_os_target[build_target->arch_os_target]);
 	}
 	library->target_used = target_found;
 	FOREACH(const char *, dependency, library->depends)
 	{
-		add_library_dependency(find_library(library_list, lib_count, dependency), library_list, lib_count);
+		add_library_dependency(build_target, find_library(library_list, lib_count, dependency), library_list, lib_count);
 	}
 	FOREACH(const char *, dependency, target_found->depends)
 	{
-		add_library_dependency(find_library(library_list, lib_count, dependency),
+		add_library_dependency(build_target,
+							   find_library(library_list, lib_count, dependency),
 							   library_list,
 							   lib_count);
 	}
@@ -150,7 +119,7 @@ INLINE JSONObject* read_manifest(const char *lib, const char *manifest_data)
 	return json;
 }
 
-static inline JSONObject *resolve_zip_library(const char *lib, const char **resulting_library)
+static inline JSONObject *resolve_zip_library(BuildTarget *build_target, const char *lib, const char **resulting_library)
 {
 	FILE *f = fopen(lib, "rb");
 	if (!f) error_exit("Failed to open library '%s' for reading.", lib);
@@ -176,7 +145,7 @@ static inline JSONObject *resolve_zip_library(const char *lib, const char **resu
 	// Create the directory for the temporary files.
 	const char *lib_name = filename(lib);
 	scratch_buffer_clear();
-	scratch_buffer_append(active_target.build_dir ? active_target.build_dir : "_temp_build");
+	scratch_buffer_append(build_target->build_dir ? build_target->build_dir : "_temp_build");
 	scratch_buffer_printf("/_c3l/%s_%x/", lib_name, file.file_crc32);
 	const char *lib_dir = scratch_buffer_copy();
 	dir_make_recursive(scratch_buffer_to_string());
@@ -197,21 +166,24 @@ static inline JSONObject *resolve_zip_library(const char *lib, const char **resu
 	return json;
 
 }
-void resolve_libraries(void)
+void resolve_libraries(BuildTarget *build_target)
 {
+	DEBUG_LOG("Resolve libraries");
 	static const char *c3lib_suffix = ".c3l";
 	const char **c3_libs = NULL;
-	unsigned libdir_count = vec_size(active_target.libdirs);
+	unsigned libdir_count = vec_size(build_target->libdirs);
 	if (libdir_count)
 	{
-		FOREACH(const char *, dir, active_target.libdirs)
+		FOREACH(const char *, dir, build_target->libdirs)
 		{
+			DEBUG_LOG("Search %s", dir);
 			file_add_wildcard_files(&c3_libs, dir, false, &c3lib_suffix, 1);
 		}
 	}
 	else
 	{
 		// Default to '.'
+		DEBUG_LOG("Search '.'");
 		file_add_wildcard_files(&c3_libs, ".", false, &c3lib_suffix, 1);
 	}
 	Library *libraries[MAX_LIB_DIRS * 2];
@@ -221,7 +193,7 @@ void resolve_libraries(void)
 		JSONObject *json;
 		if (!file_is_dir(lib))
 		{
-			json = resolve_zip_library(lib, &lib);
+			json = resolve_zip_library(build_target, lib, &lib);
 		}
 		else
 		{
@@ -232,24 +204,28 @@ void resolve_libraries(void)
 		if (lib_count == MAX_LIB_DIRS * 2) error_exit("Too many libraries added, exceeded %d.", MAX_LIB_DIRS * 2);
 		libraries[lib_count++] = add_library(json, lib);
 	}
-	FOREACH(const char *, lib_name, active_target.libs)
+	FOREACH(const char *, lib_name, build_target->libs)
 	{
-		add_library_dependency(find_library(libraries, lib_count, lib_name), libraries, lib_count);
+		add_library_dependency(build_target, find_library(libraries, lib_count, lib_name), libraries, lib_count);
 	}
 	for (size_t i = 0; i < lib_count; i++)
 	{
 		Library *library = libraries[i];
 		LibraryTarget *target = library->target_used;
 		if (!target) continue;
-		file_add_wildcard_files(&active_target.sources, library->dir, false, c3_suffix_list, 3);
-		vec_add(active_target.library_list, library);
-		const char *libdir = file_append_path(library->dir, arch_os_target[active_target.arch_os_target]);
-		if (file_is_dir(libdir)) vec_add(active_target.linker_libdirs, libdir);
-		if ((vec_size(library->execs) || vec_size(target->execs)) && active_target.trust_level < TRUST_FULL)
+		if (vec_size(target->csource_dirs))
+		{
+			vec_add(build_target->ccompling_libraries, target);
+		}
+		file_add_wildcard_files(&build_target->sources, library->dir, false, c3_suffix_list, 3);
+		vec_add(build_target->library_list, library);
+		const char *libdir = file_append_path(library->dir, arch_os_target[build_target->arch_os_target]);
+		if (file_is_dir(libdir)) vec_add(build_target->linker_libdirs, libdir);
+		if ((vec_size(library->execs) || vec_size(target->execs)) && build_target->trust_level < TRUST_FULL)
 		{
 			error_exit("Could not use library '%s' as it requires 'exec' trust level to execute (it "
 			           "is currently '%s'). Use the '--trust=full' option to enable it.",
-					   library->provides, trust_level[active_target.trust_level]);
+					   library->provides, trust_level[build_target->trust_level]);
 		}
 		FOREACH(const char *, exec, library->execs)
 		{
diff --git a/src/build/project.c b/src/build/project.c
index 20a8553ea..cca127336 100644
--- a/src/build/project.c
+++ b/src/build/project.c
@@ -4,8 +4,13 @@
 
 #include <math.h>
 #include "build_internal.h"
+#include "utils/json.h"
+
 #define MAX_SYMTAB_SIZE (1024 * 1024)
 
+#define GET_SETTING(type__, key__, strings__, comment__) \
+  (type__)get_valid_string_setting(PROJECT_JSON, target_name, json, key__, strings__, 0, ELEMENTLEN(strings__), comment__)
+
 const char *project_default_keys[][2] = {
 		{"authors", "Authors, optionally with email."},
 		{"benchfn", "Override the benchmark function."},
@@ -120,54 +125,6 @@ const char* project_target_keys[][2] = {
 
 const int project_target_keys_count = ELEMENTLEN(project_target_keys);
 
-static const char *get_string(JSONObject *table, const char *key, const char *category, const char *default_value)
-{
-	JSONObject *value = json_obj_get(table, key);
-	if (!value) return default_value;
-	if (value->type != J_STRING)
-	{
-		error_exit("%s had an invalid '%s' field that was not a string, please correct it.", category, key);
-	}
-	return value->str;
-}
-
-static const char *get_valid_string(JSONObject *table, const char *key, const char *category)
-{
-	JSONObject *value = json_obj_get(table, key);
-	if (!value) return NULL;
-	if (value->type != J_STRING)
-	{
-		error_exit("%s had an invalid '%s' field that was not a string, please correct it.", category, key);
-	}
-	return value->str;
-}
-
-int get_valid_bool(JSONObject *json, const char *key, const char *category, int default_val)
-{
-	JSONObject *value = json_obj_get(json, key);
-	if (!value) return default_val;
-	if (value->type != J_BOOL)
-	{
-		error_exit("%s had an invalid mandatory '%s' field that was not a boolean, please correct it.", category, key);
-	}
-	return value->b;
-}
-
-
-static int get_valid_string_setting(JSONObject *json, const char *key, const char *category, const char** values, int first_result, int count, const char *expected)
-{
-	JSONObject *value = json_obj_get(json, key);
-	if (!value)
-	{
-		return -1;
-	}
-	if (value->type == J_STRING)
-	{
-		int res = str_findlist(value->str, count, values);
-		if (res >= 0) return res + first_result;
-	}
-	error_exit("%s had an invalid value for '%s', expected %s", category, key, expected);
-}
 
 long get_valid_integer(JSONObject *table, const char *key, const char *category, bool mandatory)
 {
@@ -187,36 +144,7 @@ long get_valid_integer(JSONObject *table, const char *key, const char *category,
 	return (long)trunc(value->f);
 }
 
-
-static const char **get_valid_array(JSONObject *table, const char *key, const char *category, bool mandatory)
-{
-	JSONObject *value = json_obj_get(table, key);
-	if (!value)
-	{
-		if (mandatory)
-		{
-			error_exit("Error reading %s: %s was missing a mandatory '%s' field, please add it.", PROJECT_JSON, category, key);
-		}
-		return NULL;
-	}
-	if (value->type != J_ARRAY)
-	{
-		error_exit("Error reading %s: %s had an invalid mandatory '%s' field that was not an array, please correct it.", PROJECT_JSON, category, key);
-	}
-	const char **values = NULL;
-	for (unsigned i = 0; i < value->array_len; i++)
-	{
-		JSONObject *val = value->elements[i];
-		if (val->type != J_STRING)
-		{
-			error_exit("Error reading %s: %s had an invalid mandatory '%s' array that did not only hold strings, please correct it.", PROJECT_JSON, category, key);
-		}
-		vec_add(values, val->str);
-	}
-	return values;
-}
-
-static void check_json_keys(const char* valid_keys[][2], size_t key_count, JSONObject *json, const char *type)
+static void check_json_keys(const char* valid_keys[][2], size_t key_count, JSONObject *json, const char *target_name)
 {
 	static bool failed_shown = false;
 	bool failed = false;
@@ -227,7 +155,7 @@ static void check_json_keys(const char* valid_keys[][2], size_t key_count, JSONO
 		{
 			if (strcmp(key, valid_keys[j][0]) == 0) goto OK;
 		}
-		eprintf("WARNING: Unknown parameter '%s' in '%s'.\n", key, type);
+		eprintf("WARNING: Unknown parameter '%s' in '%s'.\n", key, target_name ? target_name : "default_target");
 		failed = true;
 	OK:;
 	}
@@ -238,103 +166,48 @@ static void check_json_keys(const char* valid_keys[][2], size_t key_count, JSONO
 	}
 }
 
-INLINE void append_strings_to_strings(const char*** list_of_strings_ptr, const char **strings_to_append)
+static void load_into_build_target(JSONObject *json, const char *target_name, BuildTarget *target)
 {
-	FOREACH(const char *, string, strings_to_append)
+	if (target_name)
 	{
-		vec_add(*list_of_strings_ptr, string);
-	}
-}
-
-static void target_append_strings(JSONObject *json, const char *type, const char ***list_ptr, const char *base, const char *override, const char *add, bool is_default)
-{
-	const char **value = get_valid_array(json, is_default ? base : override, type, false);
-	const char **add_value = is_default ? NULL : get_valid_array(json, add, type, false);
-	if (value && add_value)
-	{
-		error_exit("'%s' is combining both '%s' and '%s', only one may be used.", type, override, add);
-	}
-	if (value) *list_ptr = value;
-	if (add_value)
-	{
-		append_strings_to_strings(&add_value, *list_ptr);
-		*list_ptr = add_value;
-	}
-}
-static void load_into_build_target(JSONObject *json, const char *type, BuildTarget *target, bool is_default)
-{
-	if (is_default)
-	{
-		check_json_keys(project_default_keys, project_default_keys_count, json, type);
+		check_json_keys(project_target_keys, project_target_keys_count, json, target_name);
 	}
 	else
 	{
-		check_json_keys(project_target_keys, project_target_keys_count, json, type);
+		check_json_keys(project_default_keys, project_default_keys_count, json, NULL);
 	}
-	target->cc = get_string(json, "cc", type, target->cc);
+	target->cc = get_string(PROJECT_JSON, target_name, json, "cc", target->cc);
 
-	target->script_dir = get_string(json, "script-dir", type, target->script_dir);
+	target->script_dir = get_string(PROJECT_JSON, target_name, json, "script-dir", target->script_dir);
 
 	// Exec
-	const char **exec = get_valid_array(json, is_default ? "exec" : "exec-override" , type, false);
-	const char **exec_add = is_default ? NULL : get_valid_array(json, "exec-add" , type, false);
-	if (exec && exec_add)
-	{
-		error_exit("'%s' is combining both 'exec-add' and 'exec-override', only one may be used.", type);
-	}
-	if (exec_add && !target->exec)
-	{
-		target->exec = exec_add;
-		exec_add = NULL;
-	}
-	if (exec) target->exec = exec;
-	if (exec_add)
-	{
-		assert(target->exec);
-		FOREACH(const char *, exec_command, exec_add) vec_add(target->exec, exec_command);
-	}
-
-	target->output_dir = get_string(json, "output", type, target->output_dir);
+	get_list_append_strings(PROJECT_JSON, target_name, json, &target->exec, "exec", "exec-override", "exec-add");
+	
+	target->output_dir = get_string(PROJECT_JSON, target_name, json,"output", target->output_dir);
 
 	// CFlags
-	const char *cflags = get_valid_string(json, is_default ? "cflags" : "cflags-override" , type);
-	const char *cflags_add = is_default ? NULL : get_valid_string(json, "cflags-add" , type);
-	if (cflags && cflags_add)
-	{
-		error_exit("'%s' is combining both 'cflags-add' and 'cflags-override', only one may be used.", type);
-	}
-	if (cflags) target->cflags = cflags;
-	if (cflags_add)
-	{
-		if (target->cflags)
-		{
-			target->cflags = str_printf("%s %s", target->cflags, cflags_add);
-		}
-		else
-		{
-			target->cflags = cflags_add;
-		}
-	}
+	target->cflags = get_cflags(PROJECT_JSON, target_name, json, target->cflags);
+	
 	// C source dirs.
-	target_append_strings(json, type, &target->csource_dirs, "c-sources", "c-sources-override", "c-sources-add", is_default);
+	get_list_append_strings(PROJECT_JSON, target_name, json, &target->csource_dirs, "c-sources", "c-sources-override", "c-sources-add");
 
 	// Sources
-	target_append_strings(json, type, &target->source_dirs, "sources", "sources-override", "sources-add", is_default);
+	get_list_append_strings(PROJECT_JSON, target_name, json, &target->source_dirs, "sources", "sources-override", "sources-add");
 
 	// Linked-libraries - libraries to add at link time
-	target_append_strings(json, type, &target->linker_libs, "linked-libraries", "linked-libraries-override", "linked-libraries-add", is_default);
+	get_list_append_strings(PROJECT_JSON, target_name, json, &target->linker_libs, "linked-libraries", "linked-libraries-override", "linked-libraries-add");
 
 	// linker-search-paths libs dir - libraries to add at link time
-	target_append_strings(json, type, &target->linker_libdirs, "linker-search-paths", "linker-search-paths-override", "linker-search-paths-add", is_default);
+	get_list_append_strings(PROJECT_JSON, target_name, json, &target->linker_libdirs, "linker-search-paths", "linker-search-paths-override", "linker-search-paths-add");
 
 	// link-args - link args to add at link time
-	target_append_strings(json, type, &target->link_args, "link-args", "link-args-override", "link-args-add", is_default);
+	get_list_append_strings(PROJECT_JSON, target_name, json, &target->link_args, "link-args", "link-args-override", "link-args-add");
 
 	// dependency-search-paths - path to search for libraries
-	target_append_strings(json, type, &target->libdirs, "dependency-search-paths", "dependency-search-paths-override", "dependency-search-paths-add", is_default);
+	get_list_append_strings(PROJECT_JSON, target_name, json, &target->libdirs, "dependency-search-paths", "dependency-search-paths-override", "dependency-search-paths-add");
 
 	// Dependencies
-	target_append_strings(json, type, &target->libs, "dependencies", "dependencies-override", "dependencies-add", is_default);
+	get_list_append_strings(PROJECT_JSON, target_name, json, &target->libs, "dependencies", "dependencies-override", "dependencies-add");
 	FOREACH(const char *, name, target->libs)
 	{
 		if (!str_is_valid_lowercase_name(name))
@@ -351,16 +224,14 @@ static void load_into_build_target(JSONObject *json, const char *type, BuildTarg
 			[DEBUG_INFO_NONE] = "none",
 			[DEBUG_INFO_LINE_TABLES] = "line-tables"
 	};
-	DebugInfo info = get_valid_string_setting(json, "debug-info", type, debug_infos, 0, ELEMENTLEN(debug_infos), "one of 'full' 'line-table' or 'none'.");
+	DebugInfo info = GET_SETTING(DebugInfo, "debug-info", debug_infos, "one of 'full' 'line-table' or 'none'.");
 	if (info > -1) target->debug_info = info;
 
 	// Optimization Level
-	OptimizationLevel optlevel = (OptimizationLevel)get_valid_string_setting(json, "optlevel", type, optlevels, 0, ELEMENTLEN(optlevels), "`none`, `less`, `more`, `max`.");
-	target->optlevel = optlevel;
+	target->optlevel = GET_SETTING(OptimizationLevel, "optlevel", optlevels, "`none`, `less`, `more`, `max`.");
 
 	// Size optimization
-	SizeOptimizationLevel optsize = (SizeOptimizationLevel)get_valid_string_setting(json, "optsize", type, optsizes, 0, ELEMENTLEN(optlevels), "`none`, `small`, `tiny`.");
-	target->optsize = optsize;
+	target->optsize = GET_SETTING(SizeOptimizationLevel, "optsize", optlevels, "`none`, `small`, `tiny`.");
 
 	static const char *opt_settings[8] = {
 			[OPT_SETTING_O0] = "O0",
@@ -372,62 +243,63 @@ static void load_into_build_target(JSONObject *json, const char *type, BuildTarg
 			[OPT_SETTING_OSMALL] = "Os",
 			[OPT_SETTING_OTINY] = "Oz"
 	};
-	OptimizationSetting opt = (OptimizationSetting)get_valid_string_setting(json, "opt", type, opt_settings, 0, ELEMENTLEN(opt_settings), "'O0', 'O1' etc.");
+	OptimizationSetting opt = GET_SETTING(OptimizationSetting, "opt", opt_settings, "'O0', 'O1' etc.");
 	if (opt != OPT_SETTING_NOT_SET) target->optsetting = opt;
 
 	// Safety level
-	target->feature.safe_mode = (SafetyLevel)get_valid_bool(json, "safe", type, target->feature.safe_mode);
+	target->feature.safe_mode = (SafetyLevel)get_valid_bool(PROJECT_JSON, target_name, json, "safe", target->feature.safe_mode);
 
 	// Panic level
-	target->feature.panic_level = (PanicLevel)get_valid_bool(json, "panic-msg", type, target->feature.panic_level);
+	target->feature.panic_level = (PanicLevel)get_valid_bool(PROJECT_JSON, target_name, json, "panic-msg",
+	                                                          target->feature.panic_level);
 
 	// Single module
-	target->single_module = (SingleModule)get_valid_bool(json, "single-module", type, target->single_module);
+	target->single_module = (SingleModule) get_valid_bool(PROJECT_JSON, target_name, json, "single-module", target->single_module);
 
 	// Memory environment for memory constrained environments.
-	MemoryEnvironment env = get_valid_string_setting(json, "memory-env", type, memory_environment, 0, ELEMENTLEN(memory_environment), "one of 'normal', 'small', 'tiny' or 'none'.");
-	if (env > -1) target->memory_environment = env;
+	MemoryEnvironment env = GET_SETTING(MemoryEnvironment, "memory-env", memory_environment, "one of 'normal', 'small', 'tiny' or 'none'.");
+	if (env != MEMORY_ENV_NOT_SET) target->memory_environment = env;
 
 	// Symtab
-	long symtab_size = get_valid_integer(json, "symtab", type, false);
+	long symtab_size = get_valid_integer(json, "symtab", target_name, false);
 	if (symtab_size > 0)
 	{
 		if (symtab_size < 1024)
 		{
-			error_exit("Error reading %s: %s symtab was less than 1024.", PROJECT_JSON, type);
+			error_exit("Error reading %s: %s symtab was less than 1024.", PROJECT_JSON, target_name);
 		}
 		if (symtab_size > MAX_SYMTAB_SIZE)
 		{
-			error_exit("Error reading %s: %s symtab may not exceed %d.", PROJECT_JSON, type, MAX_SYMTAB_SIZE);
+			error_exit("Error reading %s: %s symtab may not exceed %d.", PROJECT_JSON, target_name, MAX_SYMTAB_SIZE);
 		}
 		target->symtab_size = (uint32_t)symtab_size;
 	}
 
 	// Target
-	const char *arch_os_string = get_valid_string(json, "target", type);
+	const char *arch_os_string = get_optional_string(PROJECT_JSON, target_name, json, "target");
 	if (arch_os_string)
 	{
 		ArchOsTarget arch_os = arch_os_target_from_string(arch_os_string);
-		if (arch_os == ARCH_OS_TARGET_DEFAULT) error_exit("Error reading %s: %s target was not valid.", PROJECT_JSON, type);
+		if (arch_os == ARCH_OS_TARGET_DEFAULT) error_exit("Error reading %s: %s target was not valid.", PROJECT_JSON, target_name);
 		target->arch_os_target = arch_os;
 	}
 
 	// Reloc
-	int reloc = get_valid_string_setting(json, "reloc", type, reloc_models, 0, ELEMENTLEN(reloc_models), "'none', 'pic', 'PIC', 'pie' or 'PIE'.");
-	if (reloc > -1) target->reloc_model = (RelocModel)reloc;
+	RelocModel reloc = GET_SETTING(RelocModel, "reloc", reloc_models, "'none', 'pic', 'PIC', 'pie' or 'PIE'.");
+	if (reloc != RELOC_DEFAULT) target->reloc_model = reloc;
 
 	// Cpu
-	target->cpu = get_string(json, "cpu", type, target->cpu);
+	target->cpu = get_string(PROJECT_JSON, target_name, json, "cpu", target->cpu);
 
 	// WinCRT
-	int wincrt = get_valid_string_setting(json, "wincrt", type, wincrt_linking, 0, ELEMENTLEN(wincrt_linking), "'none', 'static' or 'dynamic'.");
-	if (wincrt > -1) target->win.crt_linking = (WinCrtLinking)wincrt;
+	WinCrtLinking wincrt = GET_SETTING(WinCrtLinking, "wincrt", wincrt_linking, "'none', 'static' or 'dynamic'.");
+	if (wincrt != WIN_CRT_DEFAULT) target->win.crt_linking = wincrt;
 
 	// fp-math
-	int fpmath = get_valid_string_setting(json, "fp-math", type, fp_math, 0, ELEMENTLEN(fp_math), "`strict`, `relaxed` or `fast`.");
+	FpOpt fpmath = GET_SETTING(FpOpt, "fp-math", fp_math, "`strict`, `relaxed` or `fast`.");
 	if (fpmath > -1) target->feature.fp_math = fpmath;
 
-	const char **features = get_valid_array(json, "features", type, false);
+	const char **features = get_optional_string_array(PROJECT_JSON, target_name, json, "features");
 	if (features)
 	{
 		FOREACH(const char *, feature, features)
@@ -441,61 +313,61 @@ static void load_into_build_target(JSONObject *json, const char *type, BuildTarg
 	}
 
 	// x86vec
-	int x86vec = get_valid_string_setting(json, "x86vec", type, x86_vector_capability, 0, ELEMENTLEN(x86_vector_capability), "`none`, `native`, `mmx`, `sse`, `avx` or `avx512`.");
+	X86VectorCapability x86vec = GET_SETTING(X86VectorCapability, "x86vec", x86_vector_capability, "`none`, `native`, `mmx`, `sse`, `avx` or `avx512`.");
 	if (x86vec > -1) target->feature.x86_vector_capability = x86vec;
 
 	// x86vec
-	int x86cpu = get_valid_string_setting(json, "x86cpu", type, x86_cpu_set, 0, ELEMENTLEN(x86_cpu_set), "`baseline`, `ssse3`, `sse4`, `avx1`, `avx2-v1`, `avx2-v2`, `avx512` or `native`.");
-	if (x86cpu > -1) target->feature.x86_cpu_set = x86cpu;
+	X86CpuSet x86cpu = GET_SETTING(X86CpuSet, "x86cpu", x86_cpu_set, "`baseline`, `ssse3`, `sse4`, `avx1`, `avx2-v1`, `avx2-v2`, `avx512` or `native`.");
+	if (x86cpu > X86CPU_DEFAULT) target->feature.x86_cpu_set = x86cpu;
 
 	// riscvfloat
-	int riscv_float = get_valid_string_setting(json, "riscvfloat", type, riscv_capability, 0, ELEMENTLEN(riscv_capability), "`none`, `float` or `double`.");
-	if (riscv_float > -1) target->feature.riscv_float_capability = riscv_float;
+	RiscvFloatCapability riscv_float = GET_SETTING(RiscvFloatCapability, "riscvfloat", riscv_capability, "`none`, `float` or `double`.");
+	if (riscv_float != RISCVFLOAT_DEFAULT) target->feature.riscv_float_capability = riscv_float;
 
 	// winsdk
-	target->win.sdk = get_string(json, "winsdk", type, target->win.sdk);
+	target->win.sdk = get_string(PROJECT_JSON, target_name, json, "winsdk", target->win.sdk);
 
 	// windef
-	target->win.def = get_string(json, "windef", type, target->win.def);
+	target->win.def = get_string(PROJECT_JSON, target_name, json, "windef", target->win.def);
 
 	// macossdk
-	target->macos.sysroot = get_string(json, "macossdk", type, target->macos.sysroot);
+	target->macos.sysroot = get_string(PROJECT_JSON, target_name, json, "macossdk", target->macos.sysroot);
 
 	// macos-min-version
-	target->macos.min_version = get_string(json, "macos-min-version", type, target->macos.min_version);
+	target->macos.min_version = get_string(PROJECT_JSON, target_name, json, "macos-min-version", target->macos.min_version);
 
 	// macos-sdk-version
-	target->macos.sdk_version = get_string(json, "macos-sdk-version", type, target->macos.sdk_version);
+	target->macos.sdk_version = get_string(PROJECT_JSON, target_name, json, "macos-sdk-version", target->macos.sdk_version);
 
 	// Linux crt
-	target->linuxpaths.crt = get_string(json, "linux-crt", type, target->linuxpaths.crt);
+	target->linuxpaths.crt = get_string(PROJECT_JSON, target_name, json, "linux-crt", target->linuxpaths.crt);
 
 	// Linux crtbegin
-	target->linuxpaths.crtbegin = get_string(json, "linux-crtbegin", type, target->linuxpaths.crtbegin);
+	target->linuxpaths.crtbegin = get_string(PROJECT_JSON, target_name, json, "linux-crtbegin", target->linuxpaths.crtbegin);
 
 	// version
-	target->version = get_string(json, "version", type, target->version);
+	target->version = get_string(PROJECT_JSON, target_name, json, "version", target->version);
 
 	// langrev
-	target->langrev = get_string(json, "langrev", type, target->langrev);
+	target->langrev = get_string(PROJECT_JSON, target_name, json, "langrev", target->langrev);
 
 	// panicfn
-	target->panicfn = get_string(json, "panicfn", type, target->panicfn);
+	target->panicfn = get_string(PROJECT_JSON, target_name, json, "panicfn", target->panicfn);
 
 	// testfn
-	target->testfn = get_string(json, "testfn", type, target->testfn);
+	target->testfn = get_string(PROJECT_JSON, target_name, json, "testfn", target->testfn);
 
 	// testfn
-	target->benchfn = get_string(json, "benchfn", type, target->benchfn);
+	target->benchfn = get_string(PROJECT_JSON, target_name, json, "benchfn", target->benchfn);
 
 	// link-libc
-	target->link_libc = (LinkLibc)get_valid_bool(json, "link-libc", type, target->link_libc);
+	target->link_libc = (LinkLibc) get_valid_bool(PROJECT_JSON, target_name, json, "link-libc", target->link_libc);
 
 	// strip-unused
-	target->strip_unused = (StripUnused)get_valid_bool(json, "strip-unused", type, target->strip_unused);
+	target->strip_unused = (StripUnused) get_valid_bool(PROJECT_JSON, target_name, json, "strip-unused", target->strip_unused);
 
 	// linker
-	const char *linker_selection = get_string(json, "linker", type, NULL);
+	const char *linker_selection = get_optional_string(PROJECT_JSON, target_name, json, "linker");
 	if (linker_selection)
 	{
 		if (str_eq("cc", linker_selection))
@@ -516,24 +388,26 @@ static void load_into_build_target(JSONObject *json, const char *type, BuildTarg
 	}
 
 	// no-entry
-	target->no_entry = get_valid_bool(json, "no-entry", type, target->no_entry);
+	target->no_entry = get_valid_bool(PROJECT_JSON, target_name, json, "no-entry", target->no_entry);
 
 	// use-stdlib
-	target->use_stdlib = (UseStdlib)get_valid_bool(json, "use-stdlib", type, target->use_stdlib);
+	target->use_stdlib = (UseStdlib) get_valid_bool(PROJECT_JSON, target_name, json, "use-stdlib", target->use_stdlib);
 
 	// emit-stdlib
-	target->emit_stdlib = (EmitStdlib)get_valid_bool(json, "emit-stdlib", type, target->emit_stdlib);
+	target->emit_stdlib = (EmitStdlib) get_valid_bool(PROJECT_JSON, target_name, json, "emit-stdlib", target->emit_stdlib);
 
 	// single-module
-	target->single_module = (SingleModule)get_valid_bool(json, "single-module", type, target->single_module);
+	target->single_module = (SingleModule) get_valid_bool(PROJECT_JSON, target_name, json, "single-module", target->single_module);
 
 	// Trap on wrap
-	target->feature.trap_on_wrap = get_valid_bool(json, "trap-on-wrap", type, target->feature.trap_on_wrap);
+	target->feature.trap_on_wrap = get_valid_bool(PROJECT_JSON, target_name, json, "trap-on-wrap", target->feature.trap_on_wrap);
 
 	// Use the fact that they correspond to 0, 1, -1
-	target->feature.x86_struct_return = get_valid_bool(json, "x86-stack-struct-return", type, target->feature.x86_struct_return);
-	target->feature.soft_float = get_valid_bool(json, "soft-float", type, target->feature.soft_float);
-	target->feature.pass_win64_simd_as_arrays = get_valid_bool(json, "win64-simd-array", type, target->feature.pass_win64_simd_as_arrays);
+	target->feature.x86_struct_return = get_valid_bool(PROJECT_JSON, target_name, json, "x86-stack-struct-return",
+	                                                   target->feature.x86_struct_return);
+	target->feature.soft_float = get_valid_bool(PROJECT_JSON, target_name, json, "soft-float", target->feature.soft_float);
+	target->feature.pass_win64_simd_as_arrays = get_valid_bool(PROJECT_JSON, target_name, json, "win64-simd-array",
+	                                                           target->feature.pass_win64_simd_as_arrays);
 
 }
 static void project_add_target(Project *project, BuildTarget *default_target,  JSONObject *json, const char *name, const char *type, TargetType target_type)
@@ -553,7 +427,7 @@ static void project_add_target(Project *project, BuildTarget *default_target,  J
 		}
 	}
 	type = str_printf("%s %s", type, target->name);
-	load_into_build_target(json, type, target, false);
+	load_into_build_target(json, type, target);
 	update_build_target_with_opt_level(target, target->optsetting);
 }
 
@@ -578,7 +452,7 @@ static void project_add_targets(Project *project, JSONObject *project_data)
 	};
 
 	BuildTarget default_target = default_build_target;
-	load_into_build_target(project_data, "default target", &default_target, true);
+	load_into_build_target(project_data, NULL, &default_target);
 	JSONObject *targets_json = json_obj_get(project_data, "targets");
 	if (!targets_json)
 	{
@@ -596,7 +470,7 @@ static void project_add_targets(Project *project, JSONObject *project_data)
 		{
 			error_exit("Invalid data in target '%s'", key);
 		}
-		int type = get_valid_string_setting(object, "type", "Target type", targets, 0, ELEMENTLEN(targets), "a target type like 'executable' or 'static-lib'");
+		int type = get_valid_string_setting(PROJECT_JSON, NULL, object, "type", targets, 0, ELEMENTLEN(targets), "a target type like 'executable' or 'static-lib'");
 		if (type < 0) error_exit("Target %s did not contain 'type' key.", key);
 		project_add_target(project, &default_target, object, key, target_desc[type], type);
 	}
diff --git a/src/compiler/compiler.c b/src/compiler/compiler.c
index c441190d5..00d122250 100644
--- a/src/compiler/compiler.c
+++ b/src/compiler/compiler.c
@@ -253,6 +253,16 @@ static void free_arenas(void)
 	if (debug_stats) print_arena_status();
 }
 
+static int compile_cfiles(const char *compiler, const char **files, const char *flags, const char **out_files)
+{
+	int total = 0;
+	FOREACH(const char *, file, files)
+	{
+		out_files[total++] = cc_compiler(compiler, file, flags);
+	}
+	return total;
+}
+
 static void compiler_print_bench(void)
 {
 	if (debug_stats)
@@ -439,8 +449,12 @@ void compiler_compile(void)
 
 	uint32_t output_file_count = vec_size(gen_contexts);
 	unsigned cfiles = vec_size(active_target.csources);
-
-	if (output_file_count + cfiles > MAX_OUTPUT_FILES)
+	unsigned cfiles_library = 0;
+	FOREACH(LibraryTarget *, lib, active_target.ccompling_libraries)
+	{
+		cfiles_library += vec_size(lib->csources);
+	}
+	if (output_file_count + cfiles + cfiles_library > MAX_OUTPUT_FILES)
 	{
 		error_exit("Too many output files.");
 	}
@@ -450,16 +464,18 @@ void compiler_compile(void)
 	}
 
 	CompileData *compile_data = ccalloc(sizeof(CompileData), output_file_count);
-	const char **obj_files = cmalloc(sizeof(char*) * (output_file_count + cfiles));
+	const char **obj_files = cmalloc(sizeof(char*) * (output_file_count + cfiles + cfiles_library));
 
 	if (cfiles)
 	{
-		for (int i = 0; i < cfiles; i++)
-		{
-			const char *file = active_target.csources[i];
-			const char *obj = platform_compiler(file, active_target.cflags);
-			obj_files[output_file_count + i] = obj;
-		}
+		int compiled = compile_cfiles(active_target.cc, active_target.csources, active_target.cflags, &obj_files[output_file_count]);
+		assert(cfiles == compiled);
+		(void)compiled;
+	}
+	const char **obj_file_next = &obj_files[output_file_count + cfiles];
+	FOREACH(LibraryTarget *, lib, active_target.ccompling_libraries)
+	{
+		obj_file_next += compile_cfiles(lib->cc ? lib->cc : active_target.cc, lib->csources, lib->cflags, obj_file_next);
 	}
 
 	Task **tasks = NULL;
@@ -501,7 +517,7 @@ void compiler_compile(void)
 		puts("# output-files-end");
 	}
 
-	output_file_count += cfiles;
+	output_file_count += cfiles + cfiles_library;
 	free(compile_data);
 	compiler_codegen_time = bench_mark();
 
@@ -663,11 +679,12 @@ void compiler_compile(void)
 	free(obj_files);
 }
 
-static const char **target_expand_source_names(const char** dirs, const char **suffix_list, int suffix_count, bool error_on_mismatch)
+static const char **target_expand_source_names(const char *base_dir, const char** dirs, const char **suffix_list, int suffix_count, bool error_on_mismatch)
 {
 	const char **files = NULL;
 	FOREACH(const char *, name, dirs)
 	{
+		if (base_dir) name = file_append_path(base_dir, name);
 		INFO_LOG("Searching for sources in %s", name);
 		size_t name_len = strlen(name);
 		if (name_len < 1) goto INVALID_NAME;
@@ -683,7 +700,7 @@ static const char **target_expand_source_names(const char** dirs, const char **s
 			INFO_LOG("Searching for wildcard sources in %s", name);
 			if (name_len == 2 || name[name_len - 3] == '/')
 			{
-				char *path = str_copy(name, name_len - 2);
+				const char *path = str_copy(name, name_len - 2);
 				DEBUG_LOG("Reduced path %s", path);
 				file_add_wildcard_files(&files, path, true, suffix_list, suffix_count);
 				continue;
@@ -705,6 +722,15 @@ static const char **target_expand_source_names(const char** dirs, const char **s
 	return files;
 }
 
+INLINE void expand_csources(const char *base_dir, const char **source_dirs, const char ***sources_ref)
+{
+	if (source_dirs)
+	{
+		static const char* c_suffix_list[3] = { ".c" };
+		*sources_ref = target_expand_source_names(base_dir, source_dirs, c_suffix_list, 1, false);
+	}
+}
+
 void compile_target(BuildOptions *options)
 {
 	init_default_build_target(&active_target, options);
@@ -890,8 +916,6 @@ void print_syntax(BuildOptions *options)
 
 }
 
-void resolve_libraries(void);
-
 static int jump_buffer_size()
 {
 	switch (active_target.arch_os_target)
@@ -980,24 +1004,22 @@ static void execute_scripts(void)
 	dir_change(old_path);
 	free(old_path);
 }
-
 void compile()
 {
 	symtab_init(active_target.symtab_size);
-	active_target.sources = target_expand_source_names(active_target.source_dirs, c3_suffix_list, 3, true);
-	if (active_target.csource_dirs)
-	{
-		static const char* c_suffix_list[3] = { ".c" };
-		active_target.csources = target_expand_source_names(active_target.csource_dirs, c_suffix_list, 1, false);
-	}
+	active_target.sources = target_expand_source_names(NULL, active_target.source_dirs, c3_suffix_list, 3, true);
+	expand_csources(NULL, active_target.csource_dirs, &active_target.csources);
 	execute_scripts();
 	global_context.main = NULL;
 	global_context.string_type = NULL;
 	asm_target.initialized = false;
 	target_setup(&active_target);
-	resolve_libraries();
+	resolve_libraries(&active_target);
 	global_context.sources = active_target.sources;
-
+	FOREACH(LibraryTarget *, lib, active_target.ccompling_libraries)
+	{
+		expand_csources(lib->parent->dir, lib->csource_dirs, &lib->csources);
+	}
 	TokenType type = TOKEN_CONST_IDENT;
 	FOREACH(const char *, feature_flag, active_target.feature_list)
 	{
@@ -1034,10 +1056,6 @@ void compile()
 
 	if (!vec_size(active_target.sources) && !active_target.read_stdin) error_exit("No files to compile.");
 
-	if (active_target.exec)
-	{
-
-	}
 	if (active_target.lex_only)
 	{
 		compiler_lex();
diff --git a/src/compiler/compiler_internal.h b/src/compiler/compiler_internal.h
index 09be41c5f..ba8f12ae8 100644
--- a/src/compiler/compiler_internal.h
+++ b/src/compiler/compiler_internal.h
@@ -49,7 +49,6 @@ extern const char *project_default_keys[][2];
 extern const int project_default_keys_count;
 extern const char* project_target_keys[][2];
 extern const int project_target_keys_count;
-extern const char *trust_level[3];
 
 typedef struct Ast_ Ast;
 typedef struct Decl_ Decl;
@@ -3505,7 +3504,7 @@ bool static_lib_linker(const char *output_file, const char **files, unsigned fil
 bool dynamic_lib_linker(const char *output_file, const char **files, unsigned file_count);
 bool linker(const char *output_file, const char **files, unsigned file_count);
 void platform_linker(const char *output_file, const char **files, unsigned file_count);
-const char *platform_compiler(const char *file, const char* flags);
+const char *cc_compiler(const char *cc, const char *file, const char *flags);
 const char *arch_to_linker_arch(ArchType arch);
 
 #define CAT(a,b) CAT2(a,b) // force expand
diff --git a/src/compiler/linker.c b/src/compiler/linker.c
index c12ff56de..38d71d1e9 100644
--- a/src/compiler/linker.c
+++ b/src/compiler/linker.c
@@ -761,11 +761,12 @@ void platform_linker(const char *output_file, const char **files, unsigned file_
 	printf("Program linked to executable '%s'.\n", output_file);
 }
 
-const char *platform_compiler(const char *file, const char *flags)
+const char *cc_compiler(const char *cc, const char *file, const char *flags)
 {
 	const char *dir = active_target.object_file_dir;
 	if (!dir) dir = active_target.build_dir;
 
+	bool is_cl_exe = str_eq(cc, "cl.exe");
 	char *filename = NULL;
 	bool split_worked = file_namesplit(file, &filename, NULL);
 	if (!split_worked) error_exit("Cannot compile '%s'", file);
@@ -781,12 +782,21 @@ const char *platform_compiler(const char *file, const char *flags)
 		len -= 2;
 		filename[len] = 0;
 	}
-	const char *out_name = dir
-			? str_printf("%s/%s%s", dir, filename, get_object_extension())
-			: str_printf("%s%s", filename, get_object_extension());
-
+	const char *out_name;
+	if (is_cl_exe)
+	{
+		out_name = dir
+		           ? str_printf("/Fo:\"%s\\%s%s\"", dir, filename, get_object_extension())
+		           : str_printf("/Fo:\"%s%s\"", filename, get_object_extension());
+	}
+	else
+	{
+		out_name = dir
+		      ? str_printf("%s/%s%s", dir, filename, get_object_extension())
+		      : str_printf("%s%s", filename, get_object_extension());
+	}
 	const char **parts = NULL;
-	vec_add(parts, active_target.cc);
+	vec_add(parts, cc);
 
 	const bool pie_set =
 			flags != NULL &&
@@ -794,18 +804,19 @@ const char *platform_compiler(const char *file, const char *flags)
 			 strstr(flags, "-fno-pie") || // it is being set in user defined cflags.
 			 strstr(flags, "-fpie") ||
 			 strstr(flags, "-fPIE")); // strcasestr is apparently nonstandard >:(
-	if (!pie_set)
+	if (!pie_set && !is_cl_exe)
 	{
 		append_fpie_pic_options(platform_target.reloc_model, &parts);
 	}
 
-	vec_add(parts, "-c");
+	vec_add(parts, is_cl_exe ? "/c" : "-c");
 	if (flags) vec_add(parts, flags);
 	vec_add(parts, file);
-	vec_add(parts, "-o");
+	if (!is_cl_exe) vec_add(parts, "-o");
 	vec_add(parts, out_name);
 
 	const char *output = concat_string_parts(parts);
+	DEBUG_LOG("Compiling c sources using '%s'", output);
 	if (system(output) != 0)
 	{
 		error_exit("Failed to compile c sources using command '%s'.\n", output);
diff --git a/src/compiler/target.c b/src/compiler/target.c
index 4b790c28a..94b7bbf52 100644
--- a/src/compiler/target.c
+++ b/src/compiler/target.c
@@ -302,6 +302,8 @@ static char *x86_feature_name[] = {
 		[X86_FEAT_SSE4_2] = "sse4.2",
 		[X86_FEAT_AVX] = "avx",
 		[X86_FEAT_AVX2] = "avx2",
+		[X86_FEAT_AVX10_1_512] = "avx10.1-512",
+		[X86_FEAT_AVX10_1_256] = "avx10.1-256",
 		[X86_FEAT_SSE4_A] = "sse4a",
 		[X86_FEAT_FMA4] = "fma4",
 		[X86_FEAT_XOP] = "xop",
@@ -375,6 +377,7 @@ static char *x86_feature_name[] = {
 		[X86_FEAT_TBM] = "tbm",
 		[X86_FEAT_TSXLDTRK] = "tsxldtrk",
 		[X86_FEAT_UINTR] = "uintr",
+		[X86_FEAT_USERMSR] = "usermsr",
 		[X86_FEAT_VAES] = "vaes",
 		[X86_FEAT_VZEROUPPER] = "vzeroupper",
 		[X86_FEAT_WAITPKG] = "waitpkg",
@@ -664,6 +667,11 @@ static void x86_features_add_feature(X86Features *cpu_features, X86Feature featu
 		case X86_FEAT_X87:
 		case X86_FEAT_XSAVE:
 			return;
+		case X86_FEAT_AVX10_1_256:
+		case X86_FEAT_AVX10_1_512:
+		case X86_FEAT_USERMSR:
+			// TODO
+			return;
 	}
 	UNREACHABLE
 }
@@ -1864,7 +1872,10 @@ void target_setup(BuildTarget *target)
 		default:
 			break;
 	}
-
+	if (!target->cc)
+	{
+		target->cc = platform_target.os == OS_TYPE_WIN32 ? "cl.exe" : "cc";
+	}
 
 	platform_target.int128 = os_target_supports_int128(platform_target.os, platform_target.arch);
 	platform_target.vec128f = os_target_supports_vec(platform_target.os, platform_target.arch, 128, false);
diff --git a/src/compiler/target.h b/src/compiler/target.h
index 048c130fc..90b3379fa 100644
--- a/src/compiler/target.h
+++ b/src/compiler/target.h
@@ -392,6 +392,8 @@ typedef enum X64Feature
 	X86_FEAT_AMX_INT8,
 	X86_FEAT_AMX_TILE,
 	X86_FEAT_AVX,
+	X86_FEAT_AVX10_1_512,
+	X86_FEAT_AVX10_1_256,
 	X86_FEAT_AVX2,
 	X86_FEAT_AVX5124FMAPS,
 	X86_FEAT_AVX5124VNNIW,
@@ -476,6 +478,7 @@ typedef enum X64Feature
 	X86_FEAT_TBM,
 	X86_FEAT_TSXLDTRK,
 	X86_FEAT_UINTR,
+	X86_FEAT_USERMSR,
 	X86_FEAT_VAES,
 	X86_FEAT_VPCLMULQDQ,
 	X86_FEAT_VZEROUPPER,
diff --git a/src/utils/file_utils.c b/src/utils/file_utils.c
index 70797f96a..a130676ca 100644
--- a/src/utils/file_utils.c
+++ b/src/utils/file_utils.c
@@ -507,28 +507,26 @@ void file_add_wildcard_files(const char ***files, const char *path, bool recursi
 	bool path_ends_with_slash = is_path_separator(path[strlen(path) - 1]);
 	struct _wfinddata_t file_data;
 	intptr_t file_handle;
-	const char *search = str_printf(path_ends_with_slash ? "%s*.*" : "%s/*.*", path);
+	const char *search = str_printf(path_ends_with_slash ? "%s*.*" : "%s\\*.*", path);
+	DEBUG_LOG("Search %s", search);
 	if ((file_handle = _wfindfirst(win_utf8to16(search), &file_data)) == -1L) return;
 	do
 	{
-		if ((file_data.attrib & _A_SUBDIR))
+		char *name = win_utf16to8(file_data.name);
+		if (file_has_suffix_in_list(name, strlen(name), suffix_list, suffix_count))
 		{
-			if (recursive)
-			{
-				if (file_data.name[0] == L'.')
-				{
-					continue;
-				}
-				char *format = path_ends_with_slash ? "%s%ls" : "%s/%ls";
-				char *new_path = str_printf(format, path, file_data.name);
-				file_add_wildcard_files(files, new_path, true, suffix_list, suffix_count);
-			}
+			char *format = path_ends_with_slash ? "%s%s" : "%s\\%s";
+			vec_add(*files, str_printf(format, path, name));
 			continue;
 		}
-		char *name = win_utf16to8(file_data.name);
-		if (!file_has_suffix_in_list(name, strlen(name), suffix_list, suffix_count)) continue;
-		char *format = path_ends_with_slash ? "%s%s" : "%s/%s";
-		vec_add(*files, str_printf(format, path, name));
+		if (!(file_data.attrib & _A_SUBDIR)) continue;
+		if (recursive)
+		{
+			if (file_data.name[0] == L'.') continue;
+			char *format = path_ends_with_slash ? "%s%s" : "%s\\%s";
+			char *new_path = str_printf(format, path, name);
+			file_add_wildcard_files(files, new_path, true, suffix_list, suffix_count);
+		}
 	} while (_wfindnext(file_handle, &file_data) == 0);
 	_findclose(file_handle);
 }