diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 6c051493..5e2ef3dd 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -371,6 +371,10 @@ jobs:
     - uses: ./.github/actions/install-rust
       with:
         toolchain: ${{ matrix.rust }}
+
+    - name: Use specific dependency versions for Rust 1.63 compatibility.
+      run: cargo update --package=once_cell --precise=1.20.3
+
     # Don't use --all-features because some of the features have dependencies
     # that don't work on newer Rust versions.
     - run: cargo test --workspace --features=fs_utf8,arf_strings
diff --git a/cap-primitives/src/fs/file.rs b/cap-primitives/src/fs/file.rs
index 4f7df352..5b6a8c14 100644
--- a/cap-primitives/src/fs/file.rs
+++ b/cap-primitives/src/fs/file.rs
@@ -157,9 +157,6 @@ pub trait FileExt {
         Ok(())
     }
 
-    /// Returns the current position within the file.
-    fn tell(&self) -> io::Result<u64>;
-
     /// Adjust the flags associated with this file.
     fn fdstat_set_flags(&self, flags: u16) -> io::Result<()>;
 
diff --git a/cap-std/src/fs/file.rs b/cap-std/src/fs/file.rs
index 2760724a..5774c359 100644
--- a/cap-std/src/fs/file.rs
+++ b/cap-std/src/fs/file.rs
@@ -523,11 +523,6 @@ impl crate::fs::FileExt for File {
         std::os::wasi::fs::FileExt::write_vectored_at(&self.std, bufs, offset)
     }
 
-    #[inline]
-    fn tell(&self) -> std::result::Result<u64, io::Error> {
-        std::os::wasi::fs::FileExt::tell(&self.std)
-    }
-
     #[inline]
     fn fdstat_set_flags(&self, flags: u16) -> std::result::Result<(), io::Error> {
         std::os::wasi::fs::FileExt::fdstat_set_flags(&self.std, flags)
diff --git a/cap-std/src/fs_utf8/file.rs b/cap-std/src/fs_utf8/file.rs
index 81b38785..bac22a8d 100644
--- a/cap-std/src/fs_utf8/file.rs
+++ b/cap-std/src/fs_utf8/file.rs
@@ -521,11 +521,6 @@ impl crate::fs::FileExt for File {
         self.cap_std.write_vectored_at(bufs, offset)
     }
 
-    #[inline]
-    fn tell(&self) -> std::result::Result<u64, io::Error> {
-        self.cap_std.tell()
-    }
-
     #[inline]
     fn fdstat_set_flags(&self, flags: u16) -> std::result::Result<(), io::Error> {
         self.cap_std.fdstat_set_flags(flags)