diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
new file mode 100644
index 0000000..a75378b
--- /dev/null
+++ b/.gitlab-ci.yml
@@ -0,0 +1,36 @@
+# This file is a template, and might need editing before it works on your project.
+# To contribute improvements to CI/CD templates, please follow the Development guide at:
+# https://docs.gitlab.com/ee/development/cicd/templates.html
+# This specific template is located at:
+# https://gitlab.com/gitlab-org/gitlab/-/blob/master/lib/gitlab/ci/templates/Getting-Started.gitlab-ci.yml
+
+# This is a sample GitLab CI/CD configuration file that should run without any modifications.
+# It demonstrates a basic 3 stage CI/CD pipeline. Instead of real tests or scripts,
+# it uses echo commands to simulate the pipeline execution.
+#
+# A pipeline is composed of independent jobs that run scripts, grouped into stages.
+# Stages run in sequential order, but jobs within stages run in parallel.
+#
+# For more information, see: https://docs.gitlab.com/ee/ci/yaml/index.html#stages
+
+before_script:
+  - apt update -y
+  - apt install cmake libglib2.0-dev libgtk-4-dev make gcc git make clang libaudit-dev -y
+
+
+stages:          # List of stages for jobs, and their order of execution
+  - build
+
+build-job:       # This job runs in the build stage, which runs first.
+  stage: build
+  script:
+    - mkdir build
+    - cd build
+    - cmake ..
+    - make
+    - echo "Build done"
+  artifacts:
+      paths:
+        - build/ModManager
+      expire_in: 1 week
+
diff --git a/CMakeLists.txt b/CMakeLists.txt
index dfdbfd0..6c4d169 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -9,7 +9,6 @@ project(ModManager)
 
 
 set(SOURCES
-	src/main.c
 	src/steam.c
 	src/install.c
 	src/overlayfs.c
@@ -24,7 +23,8 @@ set(SOURCES
 )
 
 # add the executable
-add_executable(ModManager ${SOURCES})
+add_executable(ModManager src/main.c ${SOURCES})
+
 add_compile_options(-Wall -Wextra -pedantic -Werror)
 
 find_package(PkgConfig REQUIRED)
diff --git a/src/file.h b/src/file.h
index 852dea6..3c1be0c 100644
--- a/src/file.h
+++ b/src/file.h
@@ -4,13 +4,44 @@
 #ifndef __FILE_H__
 #define __FILE_H__
 
+
+//valid copy flags
+#define cp_DEFAULT 0
 #define CP_LINK 1
 #define CP_RECURSIVE 2
 #define CP_NO_TARGET_DIR 4
 
-int copy(const char * path, const char * dest, u_int32_t flags);
+/**
+ * @brief execute the cp command from the source to the dest
+ * @param source path to the source files
+ * @param dest path to the destination folder
+ * @param flags refer to the "valid copy flags" use them like this CP_LINK | CP_RECURSIVE
+ * @return status code
+ */
+int copy(const char * source, const char * dest, u_int32_t flags);
+
+/**
+ * @brief execute the cp command from the source to the dest
+ * @param source path to the source files
+ * @param dest path to the destination folder
+*  @param bool enable recursive rm -r
+ * @return status code
+ */
 int delete(const char * path, bool recursive);
+
+/**
+ * @brief Run the mv command
+ * @param source
+ * @param destination
+ * @return mv's exit value
+ */
 int move(const char * source, const char * destination);
+
+/**
+ * @brief Recursively rename all file and folder to lowercase.
+ *
+ * @param folder
+ */
 void casefold(const char * folder);
 
 #endif
diff --git a/src/fomod.c b/src/fomod.c
index 4fd07f0..3d5c2e8 100644
--- a/src/fomod.c
+++ b/src/fomod.c
@@ -1,4 +1,3 @@
-#include "fomod.h"
 #include <libxml/tree.h>
 #include <libxml/parser.h>
 #include <libxml/xmlstring.h>
@@ -8,11 +7,12 @@
 #include <string.h>
 #include <sys/types.h>
 #include <dirent.h>
-#include <glib.h>
 #include <stdarg.h>
+#include <unistd.h>
+
+#include "fomod.h"
 #include "file.h"
 #include "libxml/globals.h"
-#include "fomod/parser.h"
 
 int getInputCount(const char * input) {
 	char buff[2];
@@ -47,39 +47,6 @@ gint priorityCmp(gconstpointer a, gconstpointer b) {
 	return fileA->priority - fileB->priority;
 }
 
-
-char * findFOModFolder(const char * modFolder) {
-	struct dirent * dir;
-	DIR *d = opendir(modFolder);
-	if (d) {
-		while ((dir = readdir(d)) != NULL) {
-			if(g_ascii_strcasecmp(dir->d_name, "fomod") == 0) {
-				char * fomodDir = g_build_path("/", modFolder, dir->d_name, NULL);
-				closedir(d);
-				return fomodDir;
-			}
-		}
-		closedir(d);
-	}
-	return NULL;
-}
-
-char * findFOModFile(const char * fomodFolder) {
-	struct dirent * dir;
-	DIR *d = opendir(fomodFolder);
-	if (d) {
-		while ((dir = readdir(d)) != NULL) {
-			if(g_ascii_strcasecmp(dir->d_name, "moduleconfig.xml") == 0) {
-				char * fomodFile = g_build_filename(fomodFolder, dir->d_name, NULL);
-				closedir(d);
-				return fomodFile;
-			}
-		}
-		closedir(d);
-	}
-	return NULL;
-}
-
 void printfOptionsInOrder(FOModGroup_t group) {
 	for(int i = 0; i < group.pluginCount; i++) {
 		printf("%d, %s\n", i, group.plugins[i].name);
@@ -152,18 +119,75 @@ void sortGroup(FOModGroup_t * group) {
 	}
 }
 
-//TODO: support priority
-int installFOMod(const char * modFolder, const char * destination) {
-	char * fomodFolder = findFOModFolder(modFolder);
-	if(fomodFolder == NULL) {
-		fprintf(stderr, "Fomod folder not found, are you sure this is a fomod mod ?\n");
-		return EXIT_FAILURE;
-	}
+//TODO: handle error
+int processFileOperations(GList * pendingFileOperations, const char * modFolder, const char * destination) {
+	pendingFileOperations = g_list_sort(pendingFileOperations, priorityCmp);
+	GList * currentFileOperation = pendingFileOperations;
 
-	char * fomodFile = findFOModFile(fomodFolder);
-	if(fomodFile == NULL) {
+	while(currentFileOperation != NULL) {
+		//TODO: support destination
+		//no using link since priority is made to override files and link is annoying to deal with when overriding files.
+		const FOModFile_t * file = (const FOModFile_t *)currentFileOperation->data;
+		char * source = g_build_path("/", modFolder, file->source, NULL);
+
+		//fix the / and \ windows - unix paths
+		fixPath(source);
+
+		int copyResult;
+		if(file->isFolder) {
+			copyResult = copy(source, destination, CP_NO_TARGET_DIR | CP_RECURSIVE);
+		} else {
+			copyResult = copy(source, destination, 0);
+		}
+		if(copyResult != EXIT_SUCCESS) {
+			fprintf(stderr, "Copy failed, some file might be corrupted\n");
+		}
+		printf("source: %s, destination: %s\n", source, destination);
+		g_free(source);
+
+		currentFileOperation = g_list_next(currentFileOperation);
+	}
+	return EXIT_SUCCESS;
+}
+
+GList * processCondFiles(const FOMod_t * fomod, GList * flagList, GList * pendingFileOperations) {
+	for(int condId = 0; condId < fomod->condFilesCount; condId++) {
+		const FOModCondFile_t *condFile = &fomod->condFiles[condId];
+
+		bool areAllFlagsValid = true;
+
+		//checking if all flags are valid
+		for(int flagId = 0; flagId < condFile->flagCount; flagId++) {
+			const GList * link = g_list_find_custom(flagList, &(condFile->requiredFlags[flagId]), (GCompareFunc)flagEqual);
+			if(link == NULL) {
+				areAllFlagsValid = false;
+				break;
+			}
+		}
+
+		if(areAllFlagsValid) {
+			for(int fileId = 0; fileId < condFile->flagCount; fileId++) {
+				const FOModFile_t * file = &(condFile->files[fileId]);
+
+				FOModFile_t * fileCopy = malloc(sizeof(*file));
+				*fileCopy = *file;
+
+				pendingFileOperations = g_list_append(pendingFileOperations, fileCopy);
+			}
+		}
+	}
+	return pendingFileOperations;
+}
+
+int installFOMod(const char * modFolder, const char * destination) {
+	//everything should be lowercase since we use casefold() before calling any install function
+	char * fomodFolder = g_build_path("/", modFolder, "fomod", NULL);
+	char * fomodFile = g_build_filename(fomodFolder, "moduleconfig.xml", NULL);
+
+	if(access(fomodFile, F_OK) != 0) {
 		fprintf(stderr, "FOMod file not found, are you sure this is a fomod mod ?\n");
 		g_free(fomodFolder);
+		g_free(fomodFile);
 		return EXIT_FAILURE;
 	}
 
@@ -172,6 +196,7 @@ int installFOMod(const char * modFolder, const char * destination) {
 	if(returnValue != EXIT_SUCCESS) {
 		return returnValue;
 	}
+	g_free(fomodFile);
 
 	GList * flagList = NULL;
 	GList * pendingFileOperations = NULL;
@@ -179,7 +204,7 @@ int installFOMod(const char * modFolder, const char * destination) {
 	sortSteps(&fomod);
 
 	for(int i = 0; i < fomod.stepCount; i++) {
-		FOModStep_t * step = &fomod.steps[i];
+		const FOModStep_t * step = &fomod.steps[i];
 
 		bool validFlags = true;
 		for(int flagId = 0; flagId < step->flagCount; flagId++) {
@@ -280,66 +305,15 @@ int installFOMod(const char * modFolder, const char * destination) {
 		}
 	}
 
-	for(int condId = 0; condId < fomod.condFilesCount; condId++) {
-		const FOModCondFile_t *condFile = &fomod.condFiles[condId];
-
-		bool areAllFlagsValid = true;
-
-		//checking if all flags are valid
-		for(int flagId = 0; flagId < condFile->flagCount; flagId++) {
-			const GList * link = g_list_find_custom(flagList, &(condFile->requiredFlags[flagId]), (GCompareFunc)flagEqual);
-			if(link == NULL) {
-				areAllFlagsValid = false;
-				break;
-			}
-		}
-
-		if(areAllFlagsValid) {
-			for(int fileId = 0; fileId < condFile->flagCount; fileId++) {
-				const FOModFile_t * file = &(condFile->files[fileId]);
-
-				FOModFile_t * fileCopy = malloc(sizeof(*file));
-				*fileCopy = *file;
-
-				pendingFileOperations = g_list_append(pendingFileOperations, fileCopy);
-			}
-		}
-	}
-
-
-	pendingFileOperations = g_list_sort(pendingFileOperations, priorityCmp);
-	GList * currentFileOperation = pendingFileOperations;
-
-	while(currentFileOperation != NULL) {
-		//TODO: support destination
-		//TODO: handle error
-		//no using link since priority is made to override files and link is annoying to deal with when overriding files.
-		const FOModFile_t * file = (const FOModFile_t *)currentFileOperation->data;
-		char * source = g_build_path("/", modFolder, file->source, NULL);
-
-		//fix the / and \ windows - unix paths
-		fixPath(source);
-
-		int copyResult;
-		if(file->isFolder) {
-			copyResult = copy(source, destination, CP_NO_TARGET_DIR | CP_RECURSIVE);
-		} else {
-			copyResult = copy(source, destination, 0);
-		}
-		if(copyResult != EXIT_SUCCESS) {
-			fprintf(stderr, "Copy failed, some file might be corrupted\n");
-		}
-		printf("source: %s, destination: %s\n", source, destination);
-		g_free(source);
-
-		currentFileOperation = g_list_next(currentFileOperation);
-	}
 
 
+	pendingFileOperations = processCondFiles(&fomod, flagList, pendingFileOperations);
+	processFileOperations(pendingFileOperations, modFolder, destination);
 
 	printf("FOMod successfully installed!\n");
 	g_list_free(flagList);
 	g_list_free_full(pendingFileOperations, free);
 	freeFOMod(&fomod);
+	g_free(fomodFolder);
 	return EXIT_SUCCESS;
 }
diff --git a/src/fomod.h b/src/fomod.h
index 8f12725..368af57 100644
--- a/src/fomod.h
+++ b/src/fomod.h
@@ -2,9 +2,41 @@
 #define __FOMOD_H__
 
 #include <stdbool.h>
+#include <glib.h>
+#include "fomod/parser.h"
+
 #include "fomod/group.h"
 #include "fomod/xmlUtil.h"
 
+/**
+ * @brief Start a terminal based install process for fomod.
+ *
+ * @param modFolder folder of the fomod file.
+ * @param destination folder of the new mod that contains the result of the fomod process.
+ * @return int
+ */
 int installFOMod(const char * modFolder, const char * destination);
 
+/**
+ * @brief In fomod there is file operations which depends on multiple flags this function find the ones that mach our current flags and append them to a list.
+ *
+ * @param fomod a pointer to a fomod obtained by the parser
+ * @param flagList a FOModFlag_t list which contains all of the flag found.
+ * @param pendingFileOperations a list of pending FOModFile_t operation to which add the new ones. (can be null)
+ * @return a list of pendingFileOperations(FOModFile_t)
+ */
+GList * processCondFiles(const FOMod_t * fomod, GList * flagList, GList * pendingFileOperations) __attribute__((warn_unused_result));
+
+/**
+ * @brief FOModFile_t have a priority option and this function execute the file operation while taking this into account.
+ *
+ * @param pendingFileOperations list of FOModFile_t to process
+ * @param modFolder folder of the fomod file.
+ * @param destination folder of the new mod that contains the result of the process.
+ * @return error code
+ */
+int processFileOperations(GList * pendingFileOperations, const char * modFolder, const char * destination);
+
+
+
 #endif
diff --git a/src/fomod/parser.c b/src/fomod/parser.c
index 747ea76..fe8c437 100644
--- a/src/fomod/parser.c
+++ b/src/fomod/parser.c
@@ -2,6 +2,7 @@
 #include "libxml/tree.h"
 #include "xmlUtil.h"
 #include <stdlib.h>
+#include <string.h>
 
 //Maybe integrate this into the rest of the code instead of freeing after the fact
 void freeFOMod(FOMod_t * fomod) {
@@ -21,11 +22,10 @@ void freeFOMod(FOMod_t * fomod) {
 		free(condFile->requiredFlags);
 	}
 	free(fomod->condFiles);
-
 	free(fomod->moduleImage);
 	free(fomod->moduleName);
 
-	int size = countUntilNull(fomod->requiredInstallFiles);
+	int size = countUntilNull(fomod->requiredInstallFiles, sizeof(char **));
 	for(int i = 0; i < size; i++) {
 		free(fomod->requiredInstallFiles[i]);
 	}
@@ -46,6 +46,9 @@ void freeFOMod(FOMod_t * fomod) {
 		free(step->requiredFlags);
 		free(step->name);
 	}
+
+	//set every counter to zero and every pointer to null
+	memset(fomod, 0, sizeof(FOMod_t));
 }
 
 int parseVisibleNode(xmlNodePtr node, FOModStep_t * step) {
@@ -285,7 +288,7 @@ int parseFOMod(const char * fomodFile, FOMod_t* fomod) {
 					exit(EXIT_FAILURE);
 				}
 
-				int size = countUntilNull(fomod->requiredInstallFiles) + 2;
+				int size = countUntilNull(fomod->requiredInstallFiles, sizeof(char **)) + 2;
 				fomod->requiredInstallFiles = realloc(fomod->requiredInstallFiles, sizeof(char *) * size);
 				//ensure it is null terminated
 				fomod->requiredInstallFiles[size - 1] = NULL;
diff --git a/src/fomod/parser.h b/src/fomod/parser.h
index 1f665fc..6f08a5c 100644
--- a/src/fomod/parser.h
+++ b/src/fomod/parser.h
@@ -25,7 +25,19 @@ typedef struct FOMod {
 	int condFilesCount;
 } FOMod_t;
 
+/**
+ * @brief parse a fomod xml file (found inside the mod folder /fomod/moduleconfig.xml (everything should be lowercase))
+ *
+ * @param fomodFile path to the moduleconfig.xml
+ * @param fomod pointer to a new FOMod_t
+ * @return error code.
+ */
 int parseFOMod(const char * fomodFile, FOMod_t* fomod);
+
+/**
+ * @brief Free content of a fomod file.
+ * @param fomod
+ */
 void freeFOMod(FOMod_t * fomod);
 
 #endif
diff --git a/src/fomod/xmlUtil.c b/src/fomod/xmlUtil.c
index 4cc149a..b7c0d3d 100644
--- a/src/fomod/xmlUtil.c
+++ b/src/fomod/xmlUtil.c
@@ -27,10 +27,10 @@ void fixPath(char * path) {
 	}
 }
 
-int countUntilNull(void * pointers) {
+int countUntilNull(void * pointers, size_t typeSize) {
 	int i = 0;
 	while(pointers != NULL) {
-		pointers++;
+		pointers += typeSize;
 		i++;
 	}
 	return i;
diff --git a/src/fomod/xmlUtil.h b/src/fomod/xmlUtil.h
index 95b637a..e09e236 100644
--- a/src/fomod/xmlUtil.h
+++ b/src/fomod/xmlUtil.h
@@ -8,9 +8,24 @@
 typedef enum FOModOrder { ASC, DESC, ORD } FOModOrder_t;
 
 bool validateNode(xmlNodePtr * node, bool skipText, const char * names, ...);
+/**
+ * @brief Free memory of and xmlChar and return a strdup version. just to make sure there is nothing remaining in libxml
+ */
 char * freeAndDup(xmlChar * line);
 FOModOrder_t getFOModOrder(const char * order);
+/**
+ * @brief replace / by \
+ * @param path
+ */
 void fixPath(char * path);
-int countUntilNull(void * pointers);
+
+/**
+ * @brief Count the number of step before null
+ *
+ * @param pointers pointer to the list
+ * @param typeSize size of each element of the list
+ * @return size
+ */
+int countUntilNull(void * pointers, size_t typeSize);
 
 #endif
diff --git a/src/getHome.h b/src/getHome.h
index d242b54..141b34c 100644
--- a/src/getHome.h
+++ b/src/getHome.h
@@ -1 +1,8 @@
+
+
+/**
+ * @brief Get the user home dir regardless if he used sudo.
+ *
+ * @return char* path to the home dir
+ */
 char * getHome();
diff --git a/src/install.h b/src/install.h
index 9fb8a57..5a89ca6 100644
--- a/src/install.h
+++ b/src/install.h
@@ -1,6 +1,15 @@
 #ifndef __INSTALL_H__
 #define __INSTALL_H__
+#include <stdlib.h>
 #define INSTALLED_FLAG_FILE "__DO_NOT_REMOVE__"
+
+/**
+ * @brief Add a mod to the folder defined in main.h
+ *
+ * @param filePath path to the mod file
+ * @param appId game for which the mod is destined to be used with.
+ * @return EXIT_SUCCESS or EXIT_FAILURE
+ */
 int addMod(char * filePath, int appId);
 
 #endif
diff --git a/src/macro.h b/src/macro.h
index 82803a9..10b43f7 100644
--- a/src/macro.h
+++ b/src/macro.h
@@ -1,7 +1,7 @@
 #ifndef __MACRO_H__
 #define __MACRO_H__
 
-//cannot be empty it's made for fixed size array
+//cannot be empty it's made for fixed size array like the ones in steam.h
 #define LEN(array) sizeof(array) / sizeof(array[0])
 
 #endif
diff --git a/src/main.c b/src/main.c
index 24521f1..0d1f95d 100644
--- a/src/main.c
+++ b/src/main.c
@@ -64,15 +64,12 @@ int usage() {
 	printf("Use --deploy or -d <APPID> to deploy the mods for the game\n");
 	printf("Use --unbind <APPID> to rollback a deployment\n");
 	printf("Use --fomod <APPID> <MODID> to create a new mod using the result from the FOMod\n");
-	//TODO: as bonus
-	//printf("Use --start-game <APPID> to deploy the mods and launch the game through steam\n");
-	//printf("Use --steam in team cmdline options to deploy directly on game startup\n");
 	return EXIT_FAILURE;
 }
 
 int validateAppId(const char * appIdStr) {
 	//strtoul set EINVAL(after C99) if the string is invalid
-	u_int32_t appid = strtoul(appIdStr, NULL, 10);
+	unsigned long appid = strtoul(appIdStr, NULL, 10);
 	if(errno == EINVAL) {
 		printf("Appid has to be a valid number\n");
 		return -1;
@@ -89,7 +86,8 @@ int validateAppId(const char * appIdStr) {
 		return -1;
 	}
 
-	return appid;
+	//no valid appid goes far enough to justify long
+	return (int)appid;
 }
 
 int listGames(int argc, char ** argv) {
@@ -100,7 +98,7 @@ int listGames(int argc, char ** argv) {
 		printf("No game found\n");
 	} else {
 		while(gamesIds != NULL) {
-			int * gameIndex = (int*)gamesIds->data;
+			const int * gameIndex = (int*)gamesIds->data;
 			printf("%d: %s\n", GAMES_APPIDS[*gameIndex], GAMES_NAMES[*gameIndex]);
 			gamesIds = g_list_next(gamesIds);
 		}
@@ -111,9 +109,9 @@ int listGames(int argc, char ** argv) {
 
 int add(int argc, char ** argv) {
 	if(argc != 4) return usage();
-		char * appIdStr = argv[2];
+	const char * appIdStr = argv[2];
 
-	u_int32_t appid = validateAppId(appIdStr);
+	int appid = validateAppId(appIdStr);
 	if(appid < 0) {
 		return EXIT_FAILURE;
 	}
@@ -168,7 +166,7 @@ int listAllMods(int argc, char ** argv) {
 int installAndUninstallMod(int argc, char ** argv, bool install) {
 	if(argc != 4) return usage();
 	char * appIdStr = argv[2];
-	u_int32_t appid = validateAppId(appIdStr);
+	int appid = validateAppId(appIdStr);
 	if(appid < 0) {
 		return EXIT_FAILURE;
 	}
@@ -176,7 +174,7 @@ int installAndUninstallMod(int argc, char ** argv, bool install) {
 	int returnValue = EXIT_SUCCESS;
 
 	//strtoul set EINVAL if the string is invalid
-	u_int32_t modId = strtoul(argv[3], NULL, 10);
+	unsigned long modId = strtoul(argv[3], NULL, 10);
 	if(errno == EINVAL) {
 		printf("ModId has to be a valid number\n");
 		return -1;
@@ -185,6 +183,7 @@ int installAndUninstallMod(int argc, char ** argv, bool install) {
 	//might crash if no mods were installed
 	char * home = getHome();
 	char * modFolder = g_build_filename(home, MANAGER_FILES, MOD_FOLDER_NAME, appIdStr, NULL);
+	free(home);
 	GList * mods = listFilesInFolder(modFolder);
 	GList * modsFirstPointer = mods;
 
@@ -208,9 +207,14 @@ int installAndUninstallMod(int argc, char ** argv, bool install) {
 		}
 
 		//Create activated file
-		FILE * fd = fopen(modFlag, "w");
-		fwrite("", 1, 1, fd);
-		fclose(fd);
+		FILE * fd = fopen(modFlag, "w+");
+		if(fd != NULL) {
+			fwrite("", 1, 1, fd);
+			fclose(fd);
+		} else {
+			printf("Could not interact with the activation file\n");
+			returnValue = EXIT_FAILURE;
+		}
 	} else {
 		if(access(modFlag, F_OK) != 0) {
 			printf("The mod is not activated \n");
@@ -287,6 +291,8 @@ int deploy(int argc, char ** argv) {
 		free(modFlag);
 	}
 
+	g_free(modFolder);
+
 	//const char * data = "lowerdir=gameFolder,gameFolder2,gameFolder3..."
 	modsToInstall[modCount] = gameFolder;
 	modsToInstall[modCount + 1] = NULL;
@@ -297,6 +303,7 @@ int deploy(int argc, char ** argv) {
 
 	char * gameUpperDir = g_build_filename(home, MANAGER_FILES, GAME_UPPER_DIR_NAME, appIdStr, NULL);
 	char * gameWorkDir = g_build_filename(home, MANAGER_FILES, GAME_WORK_DIR_NAME, appIdStr, NULL);
+	free(home);
 
 	//unmount the game folder
 	//DETACH + FORCE allow us to be sure it will be unload.
@@ -317,12 +324,16 @@ int deploy(int argc, char ** argv) {
 		return EXIT_FAILURE;
 	}
 
+	g_free(steamGameFolder);
+	g_free(gameUpperDir);
+	g_free(gameWorkDir);
+
 	return EXIT_SUCCESS;
 }
 
 int setup(int argc, char ** argv) {
 	if(argc != 3 ) return usage();
-	char * appIdStr = argv[2];
+	const char * appIdStr = argv[2];
 	int appid = validateAppId(appIdStr);
 	if(appid < 0) {
 		return EXIT_FAILURE;
@@ -372,7 +383,7 @@ int setup(int argc, char ** argv) {
 
 int unbind(int argc, char ** argv) {
 	if(argc != 3 ) return usage();
-	char * appIdStr = argv[2];
+	const char * appIdStr = argv[2];
 	int appid = validateAppId(appIdStr);
 	if(appid < 0) {
 		return EXIT_FAILURE;
@@ -389,7 +400,7 @@ int unbind(int argc, char ** argv) {
 
 int removeMod(int argc, char ** argv) {
 	if(argc != 4) return usage();
-	char * appIdStr = argv[2];
+	const char * appIdStr = argv[2];
 	int appid = validateAppId(appIdStr);
 	if(appid < 0) {
 		printf("Invalid appid");
@@ -424,6 +435,7 @@ int removeMod(int argc, char ** argv) {
 	delete(filename, true);
 
 	g_free(filename);
+	g_free(modFolder);
 	g_list_free_full(modsFirstPointer, free);
 	return EXIT_SUCCESS;
 }
@@ -473,6 +485,9 @@ int fomod(int argc, char ** argv) {
 
 	free(destination);
 	g_list_free_full(modsFirstPointer, free);
+	g_free(modDestination);
+	g_free(modPath);
+	g_free(modFolder);
 	return returnValue;
 }
 
diff --git a/src/main.h b/src/main.h
index 02a5edd..e63cd96 100644
--- a/src/main.h
+++ b/src/main.h
@@ -5,6 +5,9 @@
 // in c "A" "B" is the same as "AB"
 #define MANAGER_FILES ".local/share/" APP_NAME
 #define MOD_FOLDER_NAME "MOD_FOLDER"
+//the folder in which the games file will be linked or copied
 #define GAME_FOLDER_NAME "GAME_FOLDER"
+//the director that will contain all modifications to game files while being deployed
 #define GAME_UPPER_DIR_NAME "UPPER_DIRS"
+//overlayfs temporary dir.
 #define GAME_WORK_DIR_NAME "WORK_DIRS"
diff --git a/src/order.c b/src/order.c
index d4ef1de..0354585 100644
--- a/src/order.c
+++ b/src/order.c
@@ -96,6 +96,5 @@ void swapPlace(int appid, int modId, int modId2) {
 	GList * list = listMods(appid);
 
 
-
 	g_list_free(list);
 }
diff --git a/src/order.h b/src/order.h
index 118381d..020b04d 100644
--- a/src/order.h
+++ b/src/order.h
@@ -15,6 +15,15 @@
  * @return GList of char containing the name of the mod folder in order
  */
 GList * listMods(int appid);
+
+/**
+ * @brief Change the mod order by swaping two mod
+ *
+ * @param appid the game
+ * index of the mod in the mod list.
+ * @param modId
+ * @param modId2
+ */
 void swapPlace(int appid, int modId, int modId2);
 
 #endif
diff --git a/src/overlayfs.h b/src/overlayfs.h
index 438335e..f9eb612 100644
--- a/src/overlayfs.h
+++ b/src/overlayfs.h
@@ -1,6 +1,15 @@
 #ifndef __OVERLAY_H__
 #define __OVERLAY_H__
 
+/**
+ * @brief Overlayfs is what make it possible to deploy to the game files without altering anything.
+ * it allows us to overlay multiple folder over the game files. like appling filters to an image.
+ * @param sources a null ended table of folder that will overlay of the game files
+ * @param dest the overlayed folder(the game data folder)
+ * @param upperdir the director that will store the changed files
+ * @param workdir a directory that will contains only temporary files.
+ * @return int error code
+ */
 int overlayMount(char ** sources, const char * dest, const char * upperdir, const char * workdir);
 
 #endif
diff --git a/src/steam.c b/src/steam.c
index b26da3e..ee77166 100644
--- a/src/steam.c
+++ b/src/steam.c
@@ -223,9 +223,9 @@ GHashTable* search_games(int * status) {
 }
 
 
-int getGameIdFromAppId(u_int32_t id) {
+int getGameIdFromAppId(u_int32_t appid) {
 	for(int k = 0; k < LEN(GAMES_APPIDS); k++) {
-		if(id == GAMES_APPIDS[k]) {
+		if(appid == GAMES_APPIDS[k]) {
 			return k;
 		}
 	}
diff --git a/src/steam.h b/src/steam.h
index dedc2e7..983ce4a 100644
--- a/src/steam.h
+++ b/src/steam.h
@@ -36,14 +36,32 @@ const static char * steamLibraries[] = {
 // order has to be the same as in GAMES_NAMES
 const static u_int32_t GAMES_APPIDS[] = {
 	489830,
+	22330,
+	377160
 };
 
 //the name of the game in the steamapps/common folder
 const static char * GAMES_NAMES[] = {
 	"Skyrim Special Edition",
+	"Oblivion",
+	"Fallout 4"
 };
 
+/**
+ * @brief list all installed games and the paths to the game's files
+ *
+ * @param status pointer to a status variable that will be modified to EXIT_SUCCESS or EXIT_FAILURE
+ * @return GHashTable* a map appid(int) => path(char *)
+ */
+ //TODO: flip the return value and parameter
 GHashTable* search_games(int * status);
-int getGameIdFromAppId(u_int32_t id);
+
+/**
+ * @brief search the index of the game inside GAMES_NAMES or GAMES_APPIDS
+ *
+ * @param appid
+ * @return -1 in case of failure or the index of the game.
+ */
+int getGameIdFromAppId(u_int32_t appid);
 
 #endif