diff --git a/CHANGELOG.md b/CHANGELOG.md
index e046f5fb8..a17370346 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -22,6 +22,8 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ## Changed
 
 - Enforced const evaluation for `path!`.
+- Removed `cstr_core` and `cty` dependencies.
+- Updated `littlefs2-sys` dependency to 0.2.0.
 
 [#47]: https://github.com/trussed-dev/littlefs2/pull/47
 [#57]: https://github.com/trussed-dev/littlefs2/pull/57
diff --git a/Cargo.toml b/Cargo.toml
index 1cc635dfb..1b071e331 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,17 +12,10 @@ documentation = "https://docs.rs/littlefs2"
 
 [dependencies]
 bitflags = "1"
-cty = "0.2.1"
 delog = "0.1.0"
 generic-array = "0.14"
 heapless = "0.7"
-
-[dependencies.cstr_core]
-default-features = false
-version = "0.2"
-
-[dependencies.littlefs2-sys]
-version = "0.1.6"
+littlefs2-sys = "0.2"
 
 [dependencies.serde]
 version = "1"
@@ -57,3 +50,6 @@ log-error = []
 # member `char name[LFS_NAME_MAX+1]`.
 # This means that if we change `traits::Storage::FILENAME_MAX_PLUS_ONE`,
 # we need to pass this on!
+
+[patch.crates-io]
+littlefs2-sys = { git = "https://github.com/trussed-dev/littlefs2-sys.git", tag = "0.2.0" }
diff --git a/src/c_stubs.rs b/src/c_stubs.rs
index 92d1dc6d4..04e29f38c 100644
--- a/src/c_stubs.rs
+++ b/src/c_stubs.rs
@@ -2,11 +2,15 @@
 //!
 //! Use this instead of linking to libc if you only need a handful of free functions
 
-use cty::{c_char, c_void, size_t};
+use core::ffi::{c_char, c_void};
+
+// see core::ffi::c_size_t: currently, size_t is always usize
+#[allow(non_camel_case_types)]
+type c_size_t = usize;
 
 extern "C" {
     // provided by `compiler-builtins`
-    fn memcpy(dst: *mut c_void, src: *const c_void, n: size_t) -> *mut c_void;
+    fn memcpy(dst: *mut c_void, src: *const c_void, n: c_size_t) -> *mut c_void;
 }
 
 /// # Safety
@@ -19,7 +23,7 @@ unsafe fn strcpy(dst: *mut c_char, src: *const c_char) -> *mut c_char {
 
 /// # Safety
 /// `s` must point to valid memory; `s` will be treated as a null terminated string
-pub unsafe fn strlen(mut s: *const c_char) -> size_t {
+pub unsafe fn strlen(mut s: *const c_char) -> c_size_t {
     let mut n = 0;
     while *s != 0 {
         s = s.add(1);
diff --git a/src/fs.rs b/src/fs.rs
index a83054045..8fa16d8d1 100644
--- a/src/fs.rs
+++ b/src/fs.rs
@@ -1,6 +1,7 @@
 //! Experimental Filesystem version using closures.
 
 use bitflags::bitflags;
+use core::ffi::{c_int, c_void};
 use core::ptr::addr_of;
 use core::ptr::addr_of_mut;
 use core::{
@@ -457,7 +458,7 @@ impl<Storage: driver::Storage> Filesystem<'_, Storage> {
                 &mut self.alloc.borrow_mut().state,
                 path.as_ptr(),
                 id,
-                &mut attribute.data as *mut _ as *mut cty::c_void,
+                &mut attribute.data as *mut _ as *mut c_void,
                 attr_max,
             )
         };
@@ -489,7 +490,7 @@ impl<Storage: driver::Storage> Filesystem<'_, Storage> {
                 &mut self.alloc.borrow_mut().state,
                 path.as_ptr(),
                 attribute.id,
-                &attribute.data as *const _ as *const cty::c_void,
+                &attribute.data as *const _ as *const c_void,
                 attribute.size as u32,
             )
         };
@@ -503,9 +504,9 @@ impl<Storage: driver::Storage> Filesystem<'_, Storage> {
         c: *const ll::lfs_config,
         block: ll::lfs_block_t,
         off: ll::lfs_off_t,
-        buffer: *mut cty::c_void,
+        buffer: *mut c_void,
         size: ll::lfs_size_t,
-    ) -> cty::c_int {
+    ) -> c_int {
         // println!("in lfs_config_read for {} bytes", size);
         let storage = unsafe { &mut *((*c).context as *mut Storage) };
         debug_assert!(!c.is_null());
@@ -522,9 +523,9 @@ impl<Storage: driver::Storage> Filesystem<'_, Storage> {
         c: *const ll::lfs_config,
         block: ll::lfs_block_t,
         off: ll::lfs_off_t,
-        buffer: *const cty::c_void,
+        buffer: *const c_void,
         size: ll::lfs_size_t,
-    ) -> cty::c_int {
+    ) -> c_int {
         // println!("in lfs_config_prog");
         let storage = unsafe { &mut *((*c).context as *mut Storage) };
         debug_assert!(!c.is_null());
@@ -538,7 +539,7 @@ impl<Storage: driver::Storage> Filesystem<'_, Storage> {
 
     /// C callback interface used by LittleFS to erase data with the lower level system below the
     /// filesystem.
-    extern "C" fn lfs_config_erase(c: *const ll::lfs_config, block: ll::lfs_block_t) -> cty::c_int {
+    extern "C" fn lfs_config_erase(c: *const ll::lfs_config, block: ll::lfs_block_t) -> c_int {
         // println!("in lfs_config_erase");
         let storage = unsafe { &mut *((*c).context as *mut Storage) };
         let off = block as usize * Storage::BLOCK_SIZE;
@@ -950,7 +951,7 @@ impl<S: driver::Storage> io::Read for File<'_, '_, S> {
             ll::lfs_file_read(
                 &mut self.fs.alloc.borrow_mut().state,
                 addr_of_mut!((*(*self.alloc.borrow_mut())).state),
-                buf.as_mut_ptr() as *mut cty::c_void,
+                buf.as_mut_ptr() as *mut c_void,
                 buf.len() as u32,
             )
         };
@@ -984,7 +985,7 @@ impl<S: driver::Storage> io::Write for File<'_, '_, S> {
             ll::lfs_file_write(
                 &mut self.fs.alloc.borrow_mut().state,
                 addr_of_mut!((*(*self.alloc.borrow_mut())).state),
-                buf.as_ptr() as *const cty::c_void,
+                buf.as_ptr() as *const c_void,
                 buf.len() as u32,
             )
         };
@@ -1214,11 +1215,11 @@ impl<'a, Storage: driver::Storage> Filesystem<'a, Storage> {
 
     // Not public, user should use `mount`, possibly after `format`
     fn new(alloc: &'a mut Allocation<Storage>, storage: &'a mut Storage) -> Self {
-        alloc.config.context = storage as *mut _ as *mut cty::c_void;
+        alloc.config.context = storage as *mut _ as *mut c_void;
 
-        alloc.config.read_buffer = alloc.cache.read.get() as *mut cty::c_void;
-        alloc.config.prog_buffer = alloc.cache.write.get() as *mut cty::c_void;
-        alloc.config.lookahead_buffer = alloc.cache.lookahead.get() as *mut cty::c_void;
+        alloc.config.read_buffer = alloc.cache.read.get() as *mut c_void;
+        alloc.config.prog_buffer = alloc.cache.write.get() as *mut c_void;
+        alloc.config.lookahead_buffer = alloc.cache.lookahead.get() as *mut c_void;
 
         Filesystem {
             alloc: RefCell::new(alloc),
diff --git a/src/path.rs b/src/path.rs
index 20fe3379a..3cfc982ef 100644
--- a/src/path.rs
+++ b/src/path.rs
@@ -1,9 +1,13 @@
 //! Paths
 
-use core::{cmp::Ordering, convert::TryFrom, fmt, iter::FusedIterator, ops, ptr, slice, str};
-
-use cstr_core::CStr;
-use cty::{c_char, size_t};
+use core::{
+    cmp::Ordering,
+    convert::TryFrom,
+    ffi::{c_char, CStr},
+    fmt,
+    iter::FusedIterator,
+    ops, ptr, slice, str,
+};
 
 use crate::consts;
 
@@ -404,7 +408,7 @@ pub struct PathBuf {
 
 /// # Safety
 /// `s` must point to valid memory; `s` will be treated as a null terminated string
-unsafe fn strlen(mut s: *const c_char) -> size_t {
+unsafe fn strlen(mut s: *const c_char) -> usize {
     let mut n = 0;
     while *s != 0 {
         s = s.add(1);