diff --git a/include/coreinit/filesystem.h b/include/coreinit/filesystem.h
index 2ef8850..5453745 100644
--- a/include/coreinit/filesystem.h
+++ b/include/coreinit/filesystem.h
@@ -11,9 +11,6 @@
  *  want to run in parallel. You must ensure the previous filesystem command
  *  has been completed before reusing the same FSCmdBlock, you do not need to
  *  reinitialise an FSCmdBlock before reusing it.
- *
- *  Calling fsDevInit initializes the stdlib devoptab, allowing for standard
- *  file IO.
  * @{
  */
 
@@ -196,12 +193,6 @@ struct FSMountSource
 };
 CHECK_SIZE(FSMountSource, 0x300);
 
-FSStatus
-fsDevInit();
-
-FSStatus
-fsDevExit();
-
 void
 FSInit();
 
diff --git a/libraries/CMakeLists.txt b/libraries/CMakeLists.txt
index 99bf979..f192320 100644
--- a/libraries/CMakeLists.txt
+++ b/libraries/CMakeLists.txt
@@ -4,5 +4,6 @@ project(libraries C)
 add_subdirectory(libdefaultheap)
 add_subdirectory(libgfd)
 add_subdirectory(libwhb)
+add_subdirectory(wutdevoptab)
 add_subdirectory(wutnewlib)
 add_subdirectory(wutstdc++)
diff --git a/libraries/wutdevoptab/CMakeLists.txt b/libraries/wutdevoptab/CMakeLists.txt
new file mode 100644
index 0000000..cdd1f3b
--- /dev/null
+++ b/libraries/wutdevoptab/CMakeLists.txt
@@ -0,0 +1,34 @@
+cmake_minimum_required(VERSION 3.2)
+project(wutdevoptab C)
+
+add_library(wutdevoptab
+   devoptab_fs.c
+   devoptab_fs_chdir.c
+   devoptab_fs_chmod.c
+   devoptab_fs_close.c
+   devoptab_fs_dirclose.c
+   devoptab_fs_dirnext.c
+   devoptab_fs_diropen.c
+   devoptab_fs_dirreset.c
+   devoptab_fs_fchmod.c
+   devoptab_fs_fstat.c
+   devoptab_fs_fsync.c
+   devoptab_fs_getmtime.c
+   devoptab_fs_link.c
+   devoptab_fs_mkdir.c
+   devoptab_fs_open.c
+   devoptab_fs_read.c
+   devoptab_fs_rename.c
+   devoptab_fs_rmdir.c
+   devoptab_fs_seek.c
+   devoptab_fs_stat.c
+   devoptab_fs_statvfs.c
+   devoptab_fs_truncate.c
+   devoptab_fs_unlink.c
+   devoptab_fs_utils.c
+   devoptab_fs_write.c)
+
+target_include_directories(wutdevoptab PRIVATE "${WUT_ROOT}/include")
+
+install(TARGETS wutdevoptab
+        ARCHIVE DESTINATION "${CMAKE_INSTALL_PREFIX}/lib")
diff --git a/libraries/wutdevoptab/devoptab_fs.c b/libraries/wutdevoptab/devoptab_fs.c
new file mode 100644
index 0000000..3defbc1
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs.c
@@ -0,0 +1,109 @@
+#include "devoptab_fs.h"
+
+static devoptab_t
+__wut_fs_devoptab =
+{
+   .name         = "fs",
+   .structSize   = sizeof(__wut_fs_file_t),
+   .open_r       = __wut_fs_open,
+   .close_r      = __wut_fs_close,
+   .write_r      = __wut_fs_write,
+   .read_r       = __wut_fs_read,
+   .seek_r       = __wut_fs_seek,
+   .fstat_r      = __wut_fs_fstat,
+   .stat_r       = __wut_fs_stat,
+   .link_r       = __wut_fs_link,
+   .unlink_r     = __wut_fs_unlink,
+   .chdir_r      = __wut_fs_chdir,
+   .rename_r     = __wut_fs_rename,
+   .mkdir_r      = __wut_fs_mkdir,
+   .dirStateSize = sizeof(__wut_fs_dir_t),
+   .diropen_r    = __wut_fs_diropen,
+   .dirreset_r   = __wut_fs_dirreset,
+   .dirnext_r    = __wut_fs_dirnext,
+   .dirclose_r   = __wut_fs_dirclose,
+   .statvfs_r    = __wut_fs_statvfs,
+   .ftruncate_r  = __wut_fs_ftruncate,
+   .fsync_r      = __wut_fs_fsync,
+   .deviceData   = NULL,
+   .chmod_r      = __wut_fs_chmod,
+   .fchmod_r     = __wut_fs_fchmod,
+   .rmdir_r      = __wut_fs_rmdir,
+};
+
+FSClient *
+__wut_devoptab_fs_client = NULL;
+
+static bool
+__wut_fs_initialised = false;
+
+FSStatus
+__init_wut_devoptab()
+{
+   FSStatus rc = 0;
+
+   if (__wut_fs_initialised) {
+      return rc;
+   }
+
+   __wut_devoptab_fs_client = memalign(0x20, sizeof(FSClient));
+   FSCmdBlock fsCmd;
+   FSMountSource mountSource;
+   char mountPath[0x80];
+   char workDir[0x83];
+
+   FSInit();
+   rc = FSAddClient(__wut_devoptab_fs_client, -1);
+
+   if (rc < 0) {
+      free(__wut_devoptab_fs_client);
+      return rc;
+   }
+
+   FSInitCmdBlock(&fsCmd);
+
+   if (rc >= 0) {
+      int dev = AddDevice(&__wut_fs_devoptab);
+
+      if(dev != -1) {
+         setDefaultDevice(dev);
+         __wut_fs_initialised = true;
+
+         // Mount the SD card
+         rc = FSGetMountSource(__wut_devoptab_fs_client, &fsCmd, FS_MOUNT_SOURCE_SD, &mountSource, -1);
+
+         if (rc < 0) {
+            return rc;
+         }
+
+         rc = FSMount(__wut_devoptab_fs_client, &fsCmd, &mountSource, mountPath, 0x80, -1);
+
+         if (rc >= 0) {
+            // chdir to SD root for general use
+            strcpy(workDir, "fs:");
+            strcat(workDir, mountPath);
+            chdir(workDir);
+         }
+      } else {
+         FSDelClient(__wut_devoptab_fs_client, -1);
+         free(__wut_devoptab_fs_client);
+         return dev;
+      }
+   }
+
+   return rc;
+}
+
+FSStatus
+__fini_wut_devoptab()
+{
+   FSStatus rc = 0;
+
+   if (!__wut_fs_initialised) {
+      return rc;
+   }
+
+   FSDelClient(__wut_devoptab_fs_client, -1);
+   free(__wut_devoptab_fs_client);
+   return rc;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs.h b/libraries/wutdevoptab/devoptab_fs.h
new file mode 100644
index 0000000..ca60e34
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs.h
@@ -0,0 +1,83 @@
+#pragma once
+#include <coreinit/filesystem.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdlib.h>
+#include <string.h>
+#include <malloc.h>
+#include <sys/dirent.h>
+#include <sys/iosupport.h>
+#include <sys/param.h>
+#include <unistd.h>
+
+/**
+ * Open file struct
+ */
+typedef struct
+{
+   //! FS handle
+   FSFileHandle fd;
+
+   //! Flags used in open(2)
+   int flags;
+
+   //! Current file offset
+   uint32_t offset;
+} __wut_fs_file_t;
+
+
+/**
+ * Open directory struct
+ */
+typedef struct
+{
+   //! Should be set to FS_DIRITER_MAGIC
+   u32 magic;
+
+   //! FS handle
+   FSDirectoryHandle fd;
+
+   //! Temporary storage for reading entries
+   FSDirectoryEntry entry_data;
+} __wut_fs_dir_t;
+
+#define FS_DIRITER_MAGIC 0x77696975
+
+extern FSClient *
+__wut_devoptab_fs_client;
+
+int       __wut_fs_open(struct _reent *r, void *fileStruct, const char *path,
+                        int flags, int mode);
+int       __wut_fs_close(struct _reent *r, void *fd);
+ssize_t   __wut_fs_write(struct _reent *r, void *fd, const char *ptr,
+                         size_t len);
+ssize_t   __wut_fs_read(struct _reent *r, void *fd, char *ptr, size_t len);
+off_t     __wut_fs_seek(struct _reent *r, void *fd, off_t pos, int dir);
+int       __wut_fs_fstat(struct _reent *r, void *fd, struct stat *st);
+int       __wut_fs_stat(struct _reent *r, const char *file, struct stat *st);
+int       __wut_fs_link(struct _reent *r, const char *existing,
+                        const char  *newLink);
+int       __wut_fs_unlink(struct _reent *r, const char *name);
+int       __wut_fs_chdir(struct _reent *r, const char *name);
+int       __wut_fs_rename(struct _reent *r, const char *oldName,
+                          const char *newName);
+int       __wut_fs_mkdir(struct _reent *r, const char *path, int mode);
+DIR_ITER* __wut_fs_diropen(struct _reent *r, DIR_ITER *dirState,
+                           const char *path);
+int       __wut_fs_dirreset(struct _reent *r, DIR_ITER *dirState);
+int       __wut_fs_dirnext(struct _reent *r, DIR_ITER *dirState, char *filename,
+                           struct stat *filestat);
+int       __wut_fs_dirclose(struct _reent *r, DIR_ITER *dirState);
+int       __wut_fs_statvfs(struct _reent *r, const char *path,
+                           struct statvfs *buf);
+int       __wut_fs_ftruncate(struct _reent *r, void *fd, off_t len);
+int       __wut_fs_fsync(struct _reent *r, void *fd);
+int       __wut_fs_chmod(struct _reent *r, const char *path, mode_t mode);
+int       __wut_fs_fchmod(struct _reent *r, void *fd, mode_t mode);
+int       __wut_fs_rmdir(struct _reent *r, const char *name);
+
+// devoptab_fs_utils.c
+char *    __wut_fs_fixpath(struct _reent *r, const char *path);
+int       __wut_fs_translate_error(FSStatus error);
diff --git a/libraries/wutdevoptab/devoptab_fs_chdir.c b/libraries/wutdevoptab/devoptab_fs_chdir.c
new file mode 100644
index 0000000..7458909
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_chdir.c
@@ -0,0 +1,33 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_chdir(struct _reent *r,
+               const char *name)
+{
+   FSStatus rc;
+
+   if (name == NULL) {
+         return -1;
+   }
+
+   char *path = __wut_fs_fixpath(r, name);
+
+   if (!path) {
+      r->_errno = ENOMEM;
+      return -1;
+   }
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   rc = FSChangeDir(__wut_devoptab_fs_client, &fsCmd, path, -1);
+   free(path);
+
+   if (rc >= 0) {
+      return 0;
+   }
+
+   r->_errno = __wut_fs_translate_error(rc);
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_chmod.c b/libraries/wutdevoptab/devoptab_fs_chmod.c
new file mode 100644
index 0000000..4b891f7
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_chmod.c
@@ -0,0 +1,29 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_chmod(struct _reent *r,
+               const char *path,
+               mode_t mode)
+{
+   FSStatus rc;
+   char *path_fix = __wut_fs_fixpath(r, path);
+
+   if (!path_fix) {
+      r->_errno = ENOMEM;
+      return -1;
+   }
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   rc = FSChangeMode(__wut_devoptab_fs_client, &fsCmd, path_fix, (FSMode)mode, -1);
+   free(path_fix);
+
+   if (rc >= 0) {
+      return 0;
+   }
+
+   r->_errno = __wut_fs_translate_error(rc);
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_close.c b/libraries/wutdevoptab/devoptab_fs_close.c
new file mode 100644
index 0000000..8ad28fa
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_close.c
@@ -0,0 +1,22 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_close(struct _reent *r,
+               void *fd)
+{
+   FSStatus rc;
+   __wut_fs_file_t *file = (__wut_fs_file_t *)fd;
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   rc = FSCloseFile(__wut_devoptab_fs_client, &fsCmd, file->fd, -1);
+
+   if (rc >= 0) {
+      return 0;
+   }
+
+   r->_errno = __wut_fs_translate_error(rc);
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_dirclose.c b/libraries/wutdevoptab/devoptab_fs_dirclose.c
new file mode 100644
index 0000000..adde150
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_dirclose.c
@@ -0,0 +1,22 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_dirclose(struct _reent *r,
+                  DIR_ITER *dirState)
+{
+   FSStatus rc;
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   __wut_fs_dir_t *dir = (__wut_fs_dir_t *)(dirState->dirStruct);
+   rc = FSCloseDir(__wut_devoptab_fs_client, &fsCmd, dir->fd, -1);
+
+   if (rc >= 0) {
+      return 0;
+   }
+
+   r->_errno = __wut_fs_translate_error(rc);
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_dirnext.c b/libraries/wutdevoptab/devoptab_fs_dirnext.c
new file mode 100644
index 0000000..1b01306
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_dirnext.c
@@ -0,0 +1,49 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_dirnext(struct _reent *r,
+                 DIR_ITER *dirState,
+                 char *filename,
+                 struct stat *filestat)
+{
+   FSStatus rc;
+   __wut_fs_dir_t *dir = (__wut_fs_dir_t *)(dirState->dirStruct);
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   // Fetch the next dir
+   memset(&dir->entry_data, 0, sizeof(dir->entry_data));
+   rc = FSReadDir(__wut_devoptab_fs_client, &fsCmd, dir->fd, &dir->entry_data, -1);
+
+   if (rc < 0) {
+      // There are no more entries; ENOENT signals end-of-directory
+      r->_errno = ENOENT;
+      return -1;
+   }
+
+   if (rc >= 0) {
+      memset(filestat, 0, sizeof(struct stat));
+
+      // Fill in the stat info
+      filestat->st_ino = 0;
+
+      if (dir->entry_data.info.flags & FS_STAT_DIRECTORY) {
+         filestat->st_mode = S_IFDIR;
+      } else {
+         filestat->st_mode = S_IFREG;
+      }
+
+      filestat->st_uid = dir->entry_data.info.owner;
+      filestat->st_gid = dir->entry_data.info.group;
+      filestat->st_size = dir->entry_data.info.size;
+
+      memset(filename, 0, NAME_MAX);
+      strcpy(filename, dir->entry_data.name);
+      return 0;
+   }
+
+   r->_errno = __wut_fs_translate_error(rc);
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_diropen.c b/libraries/wutdevoptab/devoptab_fs_diropen.c
new file mode 100644
index 0000000..2af0ea3
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_diropen.c
@@ -0,0 +1,40 @@
+#include "devoptab_fs.h"
+
+DIR_ITER *
+__wut_fs_diropen(struct _reent *r,
+                 DIR_ITER *dirState,
+                 const char *path)
+{
+   FSDirectoryHandle fd;
+   FSStatus rc;
+
+   if (path == NULL) {
+      return NULL;
+   }
+
+   char *path_fixed = __wut_fs_fixpath(r,path);
+
+   if (!path_fixed) {
+      r->_errno = ENOMEM;
+      return NULL;
+   }
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   __wut_fs_dir_t *dir = (__wut_fs_dir_t *)(dirState->dirStruct);
+   rc = FSOpenDir(__wut_devoptab_fs_client, &fsCmd, path_fixed, &fd, -1);
+
+   if (rc >= 0) {
+      dir->magic = FS_DIRITER_MAGIC;
+      dir->fd    = fd;
+      memset(&dir->entry_data, 0, sizeof(dir->entry_data));
+      free(path_fixed);
+      return dirState;
+   }
+
+   free(path_fixed);
+   r->_errno = __wut_fs_translate_error(rc);
+   return NULL;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_dirreset.c b/libraries/wutdevoptab/devoptab_fs_dirreset.c
new file mode 100644
index 0000000..36d3384
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_dirreset.c
@@ -0,0 +1,23 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_dirreset(struct _reent *r,
+                  DIR_ITER *dirState)
+{
+   FSStatus rc;
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   __wut_fs_dir_t *dir = (__wut_fs_dir_t *)(dirState->dirStruct);
+   rc = FSRewindDir(__wut_devoptab_fs_client, &fsCmd, dir->fd, -1);
+
+   if (rc >= 0) {
+      return 0;
+   }
+
+   r->_errno = __wut_fs_translate_error(rc);
+   return -1;
+}
+
diff --git a/libraries/wutdevoptab/devoptab_fs_fchmod.c b/libraries/wutdevoptab/devoptab_fs_fchmod.c
new file mode 100644
index 0000000..ecab35a
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_fchmod.c
@@ -0,0 +1,11 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_fchmod(struct _reent *r,
+                void *fd,
+                mode_t mode)
+{
+   //TODO: FSChangeMode and FSStatFile?
+   r->_errno = ENOSYS;
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_fstat.c b/libraries/wutdevoptab/devoptab_fs_fstat.c
new file mode 100644
index 0000000..4da5021
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_fstat.c
@@ -0,0 +1,30 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_fstat(struct _reent *r,
+               void *fd,
+               struct stat *st)
+{
+   FSStatus rc;
+   FSStat fsstat;
+   __wut_fs_file_t *file = (__wut_fs_file_t *)fd;
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   rc = FSGetStatFile(__wut_devoptab_fs_client, &fsCmd, file->fd, &fsstat, -1);
+
+   if (rc >= 0) {
+      memset(st, 0, sizeof(struct stat));
+      st->st_size = fsstat.size;
+      st->st_uid = fsstat.owner;
+      st->st_gid = fsstat.group;
+      st->st_nlink = 1;
+      st->st_mode = fsstat.mode;
+      return 0;
+   }
+
+   r->_errno = __wut_fs_translate_error(rc);
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_fsync.c b/libraries/wutdevoptab/devoptab_fs_fsync.c
new file mode 100644
index 0000000..76bc8e5
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_fsync.c
@@ -0,0 +1,22 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_fsync(struct _reent *r,
+               void *fd)
+{
+   FSStatus rc;
+   __wut_fs_file_t *file = (__wut_fs_file_t *)fd;
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   rc = FSFlushFile(__wut_devoptab_fs_client, &fsCmd, file->fd, -1);
+
+   if (rc >= 0) {
+      return 0;
+   }
+
+   r->_errno = __wut_fs_translate_error(rc);
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_getmtime.c b/libraries/wutdevoptab/devoptab_fs_getmtime.c
new file mode 100644
index 0000000..ff3a9cb
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_getmtime.c
@@ -0,0 +1,9 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_getmtime(const char *name,
+                  u64 *mtime)
+{
+   // TODO: Last modified time can probably be get via FSGetStatFile
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_link.c b/libraries/wutdevoptab/devoptab_fs_link.c
new file mode 100644
index 0000000..da772fe
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_link.c
@@ -0,0 +1,10 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_link(struct _reent *r,
+              const char *existing,
+              const char *newLink)
+{
+   r->_errno = ENOSYS;
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_mkdir.c b/libraries/wutdevoptab/devoptab_fs_mkdir.c
new file mode 100644
index 0000000..9bdc331
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_mkdir.c
@@ -0,0 +1,38 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_mkdir(struct _reent *r,
+               const char *path,
+               int mode)
+{
+   FSError  rc;
+
+   if (path == NULL) {
+      return -1;
+   }
+
+   char *path_fix = __wut_fs_fixpath(r, path);
+
+   if (!path_fix) {
+      r->_errno = ENOMEM;
+      return -1;
+   }
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   // TODO: Use mode to set directory attributes.
+   rc = FSMakeDir(__wut_devoptab_fs_client, &fsCmd, path_fix, -1);
+   free(path_fix);
+
+   if (rc == FS_ERROR_ALREADY_EXISTS) {
+      r->_errno = EEXIST;
+      return -1;
+   } else if(rc >= 0) {
+      return 0;
+   }
+
+   r->_errno = __wut_fs_translate_error(rc);
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_open.c b/libraries/wutdevoptab/devoptab_fs_open.c
new file mode 100644
index 0000000..813e219
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_open.c
@@ -0,0 +1,64 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_open(struct _reent *r,
+              void *fileStruct,
+              const char *path,
+              int flags,
+              int mode)
+{
+   FSFileHandle fd;
+   FSStatus rc;
+
+   if (path == NULL) {
+      return -1;
+   }
+
+   char *path_fixed = __wut_fs_fixpath(r,path);
+   if (!path_fixed) {
+      r->_errno = ENOMEM;
+      return -1;
+   }
+
+   // Get pointer to our data
+   __wut_fs_file_t *file = (__wut_fs_file_t *)fileStruct;
+   const char *fs_mode;
+
+   // Map flags to open modes
+   if (flags == 0) {
+      fs_mode = "r";
+   } else if (flags == 2) {
+      fs_mode = "r+";
+   } else if (flags == 0x601) {
+      fs_mode = "w";
+   } else if(flags == 0x602) {
+      fs_mode = "w+";
+   } else if(flags == 0x209) {
+      fs_mode = "a";
+   } else if(flags == 0x20A) {
+      fs_mode = "a+";
+   } else {
+      free(path_fixed);
+      r->_errno = EINVAL;
+      return -1;
+   }
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   // Open the file
+   rc = FSOpenFile(__wut_devoptab_fs_client, &fsCmd, path_fixed, fs_mode, &fd, -1);
+
+   if (rc >= 0) {
+      file->fd = fd;
+      file->flags = (flags & (O_ACCMODE|O_APPEND|O_SYNC));
+      FSGetPosFile(__wut_devoptab_fs_client, &fsCmd, fd, &file->offset, -1);
+      free(path_fixed);
+      return 0;
+   }
+
+   free(path_fixed);
+   r->_errno = __wut_fs_translate_error(rc);
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_read.c b/libraries/wutdevoptab/devoptab_fs_read.c
new file mode 100644
index 0000000..3f3f036
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_read.c
@@ -0,0 +1,70 @@
+#include "devoptab_fs.h"
+
+ssize_t
+__wut_fs_read(struct _reent *r,
+              void *fd,
+              char *ptr,
+              size_t len)
+{
+   FSStatus rc;
+   u32 bytes, bytesRead = 0;
+   __wut_fs_file_t *file = (__wut_fs_file_t *)fd;
+
+   // Check that the file was opened with read access
+   if ((file->flags & O_ACCMODE) == O_WRONLY) {
+      r->_errno = EBADF;
+      return -1;
+   }
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   FSStat fsstat;
+   rc = FSGetStatFile(__wut_devoptab_fs_client, &fsCmd, file->fd, &fsstat, -1);
+
+   if(rc < 0) {
+      r->_errno = __wut_fs_translate_error(rc);
+      return -1;
+   }
+
+   // Copy to internal buffer and read in chunks.
+   u8 *tmp_buffer = memalign(0x40, 8192);
+
+   while(len > 0) {
+      size_t toRead = len;
+
+      if (toRead > 8192) {
+         toRead = 8192;
+      }
+
+      // Write the data
+      rc = FSReadFile(__wut_devoptab_fs_client, &fsCmd, tmp_buffer, 1, toRead, file->fd, 0, -1);
+
+      if(rc <= 0)
+      {
+         free(tmp_buffer);
+
+         // Return partial transfer
+         if (bytesRead > 0) {
+            return bytesRead;
+         }
+
+         r->_errno = __wut_fs_translate_error(rc);
+         return -1;
+      } else {
+         bytes = rc;
+      }
+
+      // Copy to internal buffer
+      memcpy(ptr, tmp_buffer, bytes);
+
+      file->offset += bytes;
+      bytesRead    += bytes;
+      ptr          += bytes;
+      len          -= bytes;
+   }
+
+   free(tmp_buffer);
+   return bytesRead;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_rename.c b/libraries/wutdevoptab/devoptab_fs_rename.c
new file mode 100644
index 0000000..3d13715
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_rename.c
@@ -0,0 +1,46 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_rename(struct _reent *r,
+                const char *oldName,
+                const char *newName)
+{
+   FSStatus  rc;
+
+   if (oldName == NULL) {
+      return -1;
+   }
+
+   if (newName == NULL) {
+      return -1;
+   }
+
+   char *path_old = __wut_fs_fixpath(r, oldName);
+
+   if (!path_old) {
+      r->_errno = ENOMEM;
+      return -1;
+   }
+
+   char *path_new = __wut_fs_fixpath(r, newName);
+
+   if (!path_new) {
+      r->_errno = ENOMEM;
+      return -1;
+   }
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   rc = FSRename(__wut_devoptab_fs_client, &fsCmd, path_old, path_new, -1);
+   free(path_old);
+   free(path_new);
+
+   if (rc >= 0) {
+      return 0;
+   }
+
+   r->_errno = __wut_fs_translate_error(rc);
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_rmdir.c b/libraries/wutdevoptab/devoptab_fs_rmdir.c
new file mode 100644
index 0000000..32e98c1
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_rmdir.c
@@ -0,0 +1,33 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_rmdir(struct _reent *r,
+               const char *name)
+{
+   FSStatus  rc;
+
+   if (name == NULL) {
+      return -1;
+   }
+
+   char *path_fix = __wut_fs_fixpath(r, name);
+
+   if (!path_fix) {
+      r->_errno = ENOMEM;
+      return -1;
+   }
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   rc = FSRemove(__wut_devoptab_fs_client, &fsCmd, path_fix, -1);
+   free(path_fix);
+
+   if (rc >= 0) {
+      return 0;
+   }
+
+   r->_errno = __wut_fs_translate_error(rc);
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_seek.c b/libraries/wutdevoptab/devoptab_fs_seek.c
new file mode 100644
index 0000000..ad5ef24
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_seek.c
@@ -0,0 +1,64 @@
+#include "devoptab_fs.h"
+
+off_t
+__wut_fs_seek(struct _reent *r,
+              void *fd,
+              off_t pos,
+              int whence)
+{
+   FSStatus rc;
+   u64 offset;
+   __wut_fs_file_t *file = (__wut_fs_file_t *)fd;
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   FSStat fsstat;
+   rc = FSGetStatFile(__wut_devoptab_fs_client, &fsCmd, file->fd, &fsstat, -1);
+
+   if (rc < 0) {
+      r->_errno = __wut_fs_translate_error(rc);
+      return -1;
+   }
+
+   // Find the offset to see from
+   switch(whence) {
+   // Set absolute position; start offset is 0
+   case SEEK_SET:
+      offset = 0;
+      break;
+
+   // Set position relative to the current position
+   case SEEK_CUR:
+      offset = file->offset;
+      break;
+
+   // Set position relative to the end of the file
+   case SEEK_END:
+      offset = fsstat.size;
+      break;
+
+   // An invalid option was provided
+   default:
+      r->_errno = EINVAL;
+      return -1;
+   }
+
+   // TODO: A better check that prevents overflow.
+   if(pos < 0 && offset < -pos) {
+      // Don't allow seek to before the beginning of the file
+      r->_errno = EINVAL;
+      return -1;
+   }
+
+   // Update the current offset
+   file->offset = offset + pos;
+   FSStatus result = FSSetPosFile(__wut_devoptab_fs_client, &fsCmd, file->fd, file->offset, -1);
+
+   if (result < 0) {
+      return result;
+   }
+
+   return file->offset;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_stat.c b/libraries/wutdevoptab/devoptab_fs_stat.c
new file mode 100644
index 0000000..472eeaf
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_stat.c
@@ -0,0 +1,42 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_stat(struct _reent *r,
+              const char *file,
+              struct stat *st)
+{
+   int      fd;
+   FSStatus rc;
+
+   if (file == NULL) {
+      return -1;
+   }
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   // First try open as file
+   rc = FSOpenFile(__wut_devoptab_fs_client, &fsCmd, file, "r", (FSFileHandle*)&fd, -1);
+
+   if (rc >= 0) {
+      __wut_fs_file_t tmpfd = { .fd = fd };
+      rc = __wut_fs_fstat(r, &tmpfd, st);
+      FSCloseFile(__wut_devoptab_fs_client, &fsCmd, fd, -1);
+      return rc;
+   }
+
+   // File failed, so lets try open as directory
+   rc = FSOpenDir(__wut_devoptab_fs_client, &fsCmd, file, (FSDirectoryHandle*)&fd, -1);
+
+   if (rc >= 0) {
+      memset(st, 0, sizeof(struct stat));
+      st->st_nlink = 1;
+      st->st_mode = S_IFDIR | S_IRWXU | S_IRWXG | S_IRWXO;
+      FSCloseDir(__wut_devoptab_fs_client, &fsCmd, fd, -1);
+      return 0;
+   }
+
+   r->_errno = __wut_fs_translate_error(rc);
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_statvfs.c b/libraries/wutdevoptab/devoptab_fs_statvfs.c
new file mode 100644
index 0000000..7c6669f
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_statvfs.c
@@ -0,0 +1,22 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_statvfs(struct _reent *r,
+                 const char *path,
+                 struct statvfs *buf)
+{
+   FSStatus rc;
+   bool writable = false;
+   char *path_fix = __wut_fs_fixpath(r, path);
+
+   if (!path_fix)  {
+      r->_errno = ENOMEM;
+      return -1;
+   }
+
+   //TODO: FSGetFileSystemInfo
+
+   free(path_fix);
+   r->_errno = ENOSYS;
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_truncate.c b/libraries/wutdevoptab/devoptab_fs_truncate.c
new file mode 100644
index 0000000..5c546c9
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_truncate.c
@@ -0,0 +1,36 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_ftruncate(struct _reent *r,
+                   void *fd,
+                   off_t len)
+{
+   FSStatus rc;
+   __wut_fs_file_t *file = (__wut_fs_file_t *)fd;
+
+   // Make sure length is non-negative
+   if (len < 0) {
+      r->_errno = EINVAL;
+      return -1;
+   }
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   // Set the new file size
+   rc = FSSetPosFile(__wut_devoptab_fs_client, &fsCmd, file->fd, len, -1);
+
+   if (rc >= 0) {
+      return 0;
+   }
+
+   rc = FSTruncateFile(__wut_devoptab_fs_client, &fsCmd, file->fd, -1);
+
+   if (rc >= 0) {
+      return 0;
+   }
+
+   r->_errno = __wut_fs_translate_error(rc);
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_unlink.c b/libraries/wutdevoptab/devoptab_fs_unlink.c
new file mode 100644
index 0000000..ce5a40b
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_unlink.c
@@ -0,0 +1,33 @@
+#include "devoptab_fs.h"
+
+int
+__wut_fs_unlink(struct _reent *r,
+                const char *name)
+{
+   FSStatus  rc;
+
+   if (name == NULL) {
+      return -1;
+   }
+
+   char *path_fix = __wut_fs_fixpath(r, name);
+
+   if (!path_fix) {
+      r->_errno = ENOMEM;
+      return -1;
+   }
+
+   // Set up command block
+   FSCmdBlock fsCmd;
+   FSInitCmdBlock(&fsCmd);
+
+   rc = FSRemove(__wut_devoptab_fs_client, &fsCmd, path_fix, -1);
+   free(path_fix);
+
+   if (rc >= 0) {
+      return 0;
+   }
+
+   r->_errno = __wut_fs_translate_error(rc);
+   return -1;
+}
diff --git a/libraries/wutdevoptab/devoptab_fs_utils.c b/libraries/wutdevoptab/devoptab_fs_utils.c
new file mode 100644
index 0000000..9b3161f
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_utils.c
@@ -0,0 +1,47 @@
+#include "devoptab_fs.h"
+
+char *
+__wut_fs_fixpath(struct _reent *r,
+                 const char *path)
+{
+   char *p = strchr(path, ':')+1;
+
+   if(!strchr(path, ':')) {
+      p = (char*)path;
+   }
+
+   if (strlen(p) > PATH_MAX) {
+      r->_errno = ENAMETOOLONG;
+      return NULL;
+   }
+
+   char *__fixedpath = memalign(0x40, PATH_MAX+1);
+
+   if (__fixedpath == NULL) {
+      return NULL;
+   }
+
+   // cwd is handled by coreinit, so just strip the 'fs:' if it exists
+   strcpy(__fixedpath, p);
+   return __fixedpath;
+}
+
+int
+__wut_fs_translate_error(FSStatus error)
+{
+   switch (error) {
+   case FS_STATUS_CANCELLED:
+      return EINVAL;
+   case FS_STATUS_EXISTS:
+      return EEXIST;
+   case FS_STATUS_NOT_FOUND:
+      return ENOENT;
+   case FS_STATUS_STORAGE_FULL:
+      return ENOSPC;
+   case FS_ERROR_INVALID_PATH:
+      return ENAMETOOLONG;
+   default:
+      return (int)error;
+   }
+}
+
diff --git a/libraries/wutdevoptab/devoptab_fs_write.c b/libraries/wutdevoptab/devoptab_fs_write.c
new file mode 100644
index 0000000..a57fba3
--- /dev/null
+++ b/libraries/wutdevoptab/devoptab_fs_write.c
@@ -0,0 +1,61 @@
+#include "devoptab_fs.h"
+
+ssize_t
+__wut_fs_write(struct _reent *r,
+               void *fd,
+               const char *ptr,
+               size_t len)
+{
+   FSStatus rc;
+   u32 bytes, bytesWritten = 0;
+   __wut_fs_file_t *file = (__wut_fs_file_t *)fd;
+
+   // Check that the file was opened with write access
+   if ((file->flags & O_ACCMODE) == O_RDONLY) {
+      r->_errno = EBADF;
+      return -1;
+   }
+
+   // Copy to internal buffer and write in chunks.
+   u8 *tmp_buffer = memalign(0x40, 8192);
+
+   while(len > 0) {
+      size_t toWrite = len;
+
+      if (toWrite > 8192) {
+         toWrite = 8192;
+      }
+
+      // Copy to internal buffer
+      memcpy(tmp_buffer, ptr, toWrite);
+
+      // Set up command block
+      FSCmdBlock fsCmd;
+      FSInitCmdBlock(&fsCmd);
+
+      // Write the data
+      rc = FSWriteFile(__wut_devoptab_fs_client, &fsCmd, tmp_buffer, 1, toWrite, file->fd, 0, -1);
+
+      if (rc < 0) {
+         free(tmp_buffer);
+
+         // Return partial transfer
+         if (bytesWritten > 0) {
+            return bytesWritten;
+         }
+
+         r->_errno = __wut_fs_translate_error(rc);
+         return -1;
+      } else {
+         bytes = rc;
+      }
+
+      file->offset += bytes;
+      bytesWritten += bytes;
+      ptr          += bytes;
+      len          -= bytes;
+   }
+
+   free(tmp_buffer);
+   return bytesWritten;
+}