diff --git a/Cargo.lock b/Cargo.lock
index a23b871..5d9ea8b 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -304,7 +304,6 @@ dependencies = [
 name = "loot-condition-interpreter-ffi"
 version = "5.3.3"
 dependencies = [
- "libc",
  "loot-condition-interpreter",
 ]
 
diff --git a/ffi/Cargo.toml b/ffi/Cargo.toml
index f97d201..a21f3a7 100644
--- a/ffi/Cargo.toml
+++ b/ffi/Cargo.toml
@@ -8,7 +8,6 @@ edition.workspace = true
 
 [dependencies]
 loot-condition-interpreter = { path = ".." }
-libc = "0.2"
 
 [lib]
 name = "loot_condition_interpreter_ffi"
diff --git a/ffi/src/helpers.rs b/ffi/src/helpers.rs
index 0cb5c34..1f66f19 100644
--- a/ffi/src/helpers.rs
+++ b/ffi/src/helpers.rs
@@ -2,7 +2,6 @@ use std::ffi::{c_char, c_int, CStr, CString};
 use std::path::PathBuf;
 use std::slice;
 
-use libc::size_t;
 use loot_condition_interpreter::{Error, GameType};
 
 use super::ERROR_MESSAGE;
@@ -68,7 +67,7 @@ pub(crate) unsafe fn to_str<'a>(c_string: *const c_char) -> Result<&'a str, c_in
 
 pub(crate) unsafe fn to_vec<U, V, F>(
     array: *const U,
-    array_size: size_t,
+    array_size: usize,
     mapper: F,
 ) -> Result<Vec<V>, c_int>
 where
@@ -86,14 +85,14 @@ where
 
 pub(crate) unsafe fn to_str_vec<'a>(
     array: *const *const c_char,
-    array_size: size_t,
+    array_size: usize,
 ) -> Result<Vec<&'a str>, c_int> {
     to_vec(array, array_size, |c| to_str(*c))
 }
 
 pub(crate) unsafe fn to_path_buf_vec(
     array: *const *const c_char,
-    array_size: size_t,
+    array_size: usize,
 ) -> Result<Vec<PathBuf>, c_int> {
     to_vec(array, array_size, |c| to_str(*c).map(PathBuf::from))
 }
@@ -105,14 +104,14 @@ unsafe fn map_plugin_version(c_object: &plugin_version) -> Result<(String, Strin
 
 pub(crate) unsafe fn map_plugin_versions(
     plugin_versions: *const plugin_version,
-    num_plugins: size_t,
+    num_plugins: usize,
 ) -> Result<Vec<(String, String)>, c_int> {
     to_vec(plugin_versions, num_plugins, |v| map_plugin_version(v))
 }
 
 pub(crate) unsafe fn map_plugin_crcs(
     plugin_crcs: *const plugin_crc,
-    num_entries: size_t,
+    num_entries: usize,
 ) -> Result<Vec<(String, u32)>, c_int> {
     to_vec(plugin_crcs, num_entries, |v| {
         to_str(v.plugin_name).map(|s| (s.into(), v.crc))
diff --git a/ffi/src/state.rs b/ffi/src/state.rs
index 2e102f7..a062f87 100644
--- a/ffi/src/state.rs
+++ b/ffi/src/state.rs
@@ -3,7 +3,6 @@ use std::panic::catch_unwind;
 use std::path::PathBuf;
 use std::sync::RwLock;
 
-use libc::size_t;
 use loot_condition_interpreter::State;
 
 use crate::constants::{
@@ -74,7 +73,7 @@ pub unsafe extern "C" fn lci_state_destroy(state: *mut lci_state) {
 pub unsafe extern "C" fn lci_state_set_active_plugins(
     state: *mut lci_state,
     plugin_names: *const *const c_char,
-    num_plugins: size_t,
+    num_plugins: usize,
 ) -> c_int {
     catch_unwind(|| {
         if state.is_null() {
@@ -112,7 +111,7 @@ pub unsafe extern "C" fn lci_state_set_active_plugins(
 pub unsafe extern "C" fn lci_state_set_plugin_versions(
     state: *mut lci_state,
     plugin_versions: *const plugin_version,
-    num_plugins: size_t,
+    num_plugins: usize,
 ) -> c_int {
     catch_unwind(|| {
         if state.is_null() {
@@ -150,7 +149,7 @@ pub unsafe extern "C" fn lci_state_set_plugin_versions(
 pub unsafe extern "C" fn lci_state_set_crc_cache(
     state: *mut lci_state,
     entries: *const plugin_crc,
-    num_entries: size_t,
+    num_entries: usize,
 ) -> c_int {
     catch_unwind(|| {
         if state.is_null() {
@@ -213,7 +212,7 @@ pub unsafe extern "C" fn lci_state_clear_condition_cache(state: *mut lci_state)
 pub unsafe extern "C" fn lci_state_set_additional_data_paths(
     state: *mut lci_state,
     paths: *const *const c_char,
-    num_paths: size_t,
+    num_paths: usize,
 ) -> c_int {
     catch_unwind(|| {
         if state.is_null() || (paths.is_null() && num_paths != 0) {