diff --git a/Cargo.toml b/Cargo.toml
index 31179e59a7c..c4ce8b6b033 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -57,7 +57,6 @@ send_wrapper = "0.6"
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0.61"
 rayon = "1.6.1"
-widestring = "0.5.1"
 futures = "0.3.28"
 
 [build-dependencies]
diff --git a/tests/test_pep_587.rs b/tests/test_pep_587.rs
deleted file mode 100644
index 24e1f07d2d8..00000000000
--- a/tests/test_pep_587.rs
+++ /dev/null
@@ -1,63 +0,0 @@
-#![cfg(all(Py_3_8, not(any(PyPy, Py_LIMITED_API))))]
-
-use pyo3::ffi;
-
-#[cfg(Py_3_10)]
-use widestring::WideCString;
-
-#[test]
-fn test_default_interpreter() {
-    macro_rules! ensure {
-        ($py_call:expr) => {{
-            let status = $py_call;
-            unsafe {
-                if ffi::PyStatus_Exception(status) != 0 {
-                    ffi::Py_ExitStatusException(status);
-                }
-            }
-        }};
-    }
-
-    let mut preconfig = unsafe { std::mem::zeroed() };
-
-    unsafe { ffi::PyPreConfig_InitPythonConfig(&mut preconfig) };
-    preconfig.utf8_mode = 1;
-
-    ensure!(unsafe { ffi::Py_PreInitialize(&preconfig) });
-
-    let mut config = unsafe { std::mem::zeroed() };
-    unsafe { ffi::PyConfig_InitPythonConfig(&mut config) };
-
-    // Require manually calling _Py_InitializeMain to exercise more ffi code
-    #[allow(clippy::used_underscore_binding)]
-    {
-        config._init_main = 0;
-    }
-
-    #[cfg(Py_3_10)]
-    unsafe {
-        ffi::PyConfig_SetBytesString(
-            &mut config,
-            &mut config.program_name,
-            "some_test\0".as_ptr().cast(),
-        );
-    }
-
-    ensure!(unsafe { ffi::Py_InitializeFromConfig(&config) });
-
-    // The GIL is held.
-    assert_eq!(unsafe { ffi::PyGILState_Check() }, 1);
-
-    // Now proceed with the Python main initialization.
-    ensure!(unsafe { ffi::_Py_InitializeMain() });
-
-    // The GIL is held after finishing initialization.
-    assert_eq!(unsafe { ffi::PyGILState_Check() }, 1);
-
-    // Confirm program name set above was picked up correctly
-    #[cfg(Py_3_10)]
-    {
-        let program_name = unsafe { WideCString::from_ptr_str(ffi::Py_GetProgramName().cast()) };
-        assert_eq!(program_name.to_string().unwrap(), "some_test");
-    }
-}