diff --git a/src/spiffs.h b/src/spiffs.h
index 2912f59..ff5aa4f 100644
--- a/src/spiffs.h
+++ b/src/spiffs.h
@@ -315,7 +315,7 @@ void SPIFFS_unmount(spiffs *fs);
  * @param path          the path of the new file
  * @param mode          ignored, for posix compliance
  */
-s32_t SPIFFS_creat(spiffs *fs, char *path, spiffs_mode mode);
+s32_t SPIFFS_creat(spiffs *fs, const char *path, spiffs_mode mode);
 
 /**
  * Opens/creates a file.
@@ -326,7 +326,7 @@ s32_t SPIFFS_creat(spiffs *fs, char *path, spiffs_mode mode);
  *                      SPIFFS_WR_ONLY, SPIFFS_RDWR, SPIFFS_DIRECT
  * @param mode          ignored, for posix compliance
  */
-spiffs_file SPIFFS_open(spiffs *fs, char *path, spiffs_flags flags, spiffs_mode mode);
+spiffs_file SPIFFS_open(spiffs *fs, const char *path, spiffs_flags flags, spiffs_mode mode);
 
 
 /**
@@ -381,7 +381,7 @@ s32_t SPIFFS_lseek(spiffs *fs, spiffs_file fh, s32_t offs, int whence);
  * @param fs            the file system struct
  * @param path          the path of the file to remove
  */
-s32_t SPIFFS_remove(spiffs *fs, char *path);
+s32_t SPIFFS_remove(spiffs *fs, const char *path);
 
 /**
  * Removes a file by filehandle
@@ -396,7 +396,7 @@ s32_t SPIFFS_fremove(spiffs *fs, spiffs_file fh);
  * @param path          the path of the file to stat
  * @param s             the stat struct to populate
  */
-s32_t SPIFFS_stat(spiffs *fs, char *path, spiffs_stat *s);
+s32_t SPIFFS_stat(spiffs *fs, const char *path, spiffs_stat *s);
 
 /**
  * Gets file status by filehandle
@@ -426,7 +426,7 @@ s32_t SPIFFS_close(spiffs *fs, spiffs_file fh);
  * @param old           path of file to rename
  * @param newPath       new path of file
  */
-s32_t SPIFFS_rename(spiffs *fs, char *old, char *newPath);
+s32_t SPIFFS_rename(spiffs *fs, const char *old, const char *newPath);
 
 /**
  * Returns last error of last file operation.
@@ -449,7 +449,7 @@ void SPIFFS_clearerr(spiffs *fs);
  * @param name          the name of the directory
  * @param d             pointer the directory stream to be populated
  */
-spiffs_DIR *SPIFFS_opendir(spiffs *fs, char *name, spiffs_DIR *d);
+spiffs_DIR *SPIFFS_opendir(spiffs *fs, const char *name, spiffs_DIR *d);
 
 /**
  * Closes a directory stream
diff --git a/src/spiffs_hydrogen.c b/src/spiffs_hydrogen.c
index aabd471..638d7de 100644
--- a/src/spiffs_hydrogen.c
+++ b/src/spiffs_hydrogen.c
@@ -166,7 +166,7 @@ void SPIFFS_clearerr(spiffs *fs) {
   fs->err_code = SPIFFS_OK;
 }
 
-s32_t SPIFFS_creat(spiffs *fs, char *path, spiffs_mode mode) {
+s32_t SPIFFS_creat(spiffs *fs, const char *path, spiffs_mode mode) {
   (void)mode;
   SPIFFS_API_CHECK_CFG(fs);
   SPIFFS_API_CHECK_MOUNT(fs);
@@ -182,7 +182,7 @@ s32_t SPIFFS_creat(spiffs *fs, char *path, spiffs_mode mode) {
   return 0;
 }
 
-spiffs_file SPIFFS_open(spiffs *fs, char *path, spiffs_flags flags, spiffs_mode mode) {
+spiffs_file SPIFFS_open(spiffs *fs, const char *path, spiffs_flags flags, spiffs_mode mode) {
   (void)mode;
   SPIFFS_API_CHECK_CFG(fs);
   SPIFFS_API_CHECK_MOUNT(fs);
@@ -522,7 +522,7 @@ s32_t SPIFFS_lseek(spiffs *fs, spiffs_file fh, s32_t offs, int whence) {
   return offs;
 }
 
-s32_t SPIFFS_remove(spiffs *fs, char *path) {
+s32_t SPIFFS_remove(spiffs *fs, const char *path) {
   SPIFFS_API_CHECK_CFG(fs);
   SPIFFS_API_CHECK_MOUNT(fs);
   SPIFFS_LOCK(fs);
@@ -607,7 +607,7 @@ static s32_t spiffs_stat_pix(spiffs *fs, spiffs_page_ix pix, spiffs_file fh, spi
   return res;
 }
 
-s32_t SPIFFS_stat(spiffs *fs, char *path, spiffs_stat *s) {
+s32_t SPIFFS_stat(spiffs *fs, const char *path, spiffs_stat *s) {
   SPIFFS_API_CHECK_CFG(fs);
   SPIFFS_API_CHECK_MOUNT(fs);
   SPIFFS_LOCK(fs);
@@ -720,7 +720,7 @@ s32_t SPIFFS_close(spiffs *fs, spiffs_file fh) {
   return res;
 }
 
-s32_t SPIFFS_rename(spiffs *fs, char *old, char *new) {
+s32_t SPIFFS_rename(spiffs *fs, const char *old, const char *new) {
   SPIFFS_API_CHECK_CFG(fs);
   SPIFFS_API_CHECK_MOUNT(fs);
   SPIFFS_LOCK(fs);
@@ -760,7 +760,7 @@ s32_t SPIFFS_rename(spiffs *fs, char *old, char *new) {
   return res;
 }
 
-spiffs_DIR *SPIFFS_opendir(spiffs *fs, char *name, spiffs_DIR *d) {
+spiffs_DIR *SPIFFS_opendir(spiffs *fs, const char *name, spiffs_DIR *d) {
   (void)name;
 
   if (!SPIFFS_CHECK_CFG((fs))) {