diff '--color=auto' -ruwN source/Cargo.toml source-new/Cargo.toml
--- source/Cargo.toml	2025-09-11 01:59:14.785564526 -0400
+++ source-new/Cargo.toml	2025-09-11 01:59:45.885553436 -0400
@@ -35,12 +35,12 @@
 
 bitflags = "2.5.0"
 errno = "0.3.0"
-libc = "0.2"
+libc = { git = "https://github.com/rust-lang/libc", rev = "b31ee9b22f99354f2ca00c68d038d6f377c8b8a4", features = ["extra_traits"] }
 # lru pulls in hashbrown by default, which uses a faster (though less DoS resistant) hashing algo.
 # disabling default features uses the stdlib instead, but it doubles the time to rewrite the history
 # files as of 22 April 2024.
 lru = "0.13.0"
-nix = { version = "0.30.1", default-features = false, features = [
+nix = { git = "https://github.com/joshuamegnauth54/nix", branch = "redox-fish-no-merge", default-features = false, features = [
     "event",
     "inotify",
     "resource",
diff '--color=auto' -ruwN source/src/exec.rs source-new/src/exec.rs
--- source/src/exec.rs	2025-09-11 01:59:14.596625190 -0400
+++ source-new/src/exec.rs	2025-09-11 02:00:00.315286369 -0400
@@ -33,7 +33,6 @@
 use crate::nix::{getpid, isatty};
 use crate::null_terminated_array::OwningNullTerminatedArray;
 use crate::parser::{Block, BlockId, BlockType, EvalRes, Parser};
-#[cfg(FISH_USE_POSIX_SPAWN)]
 use crate::proc::Pid;
 use crate::proc::{
     hup_jobs, is_interactive_session, jobs_requiring_warning_on_exit, no_exec,
@@ -390,7 +389,7 @@
 ) -> ! {
     // This function never returns, so we take certain liberties with constness.
 
-    unsafe { libc::execve(actual_cmd.as_ptr(), argv.get(), envv.get()) };
+    unsafe { libc::execve(actual_cmd.as_ptr(), argv.get().cast(), envv.get().cast()) };
     let err = errno();
 
     // The shebang wasn't introduced until UNIX Seventh Edition, so if
@@ -413,7 +412,11 @@
             // not what we would pass as argv0.
             argv2[1] = actual_cmd.as_ptr();
             unsafe {
-                libc::execve(_PATH_BSHELL.load(Ordering::Relaxed), &argv2[0], envv.get());
+                libc::execve(
+                    _PATH_BSHELL.load(Ordering::Relaxed),
+                    argv2.as_ptr().cast(),
+                    envv.get().cast(),
+                );
             }
         }
     }
diff '--color=auto' -ruwN source/src/fork_exec/postfork.rs source-new/src/fork_exec/postfork.rs
--- source/src/fork_exec/postfork.rs	2025-09-11 01:59:14.828576001 -0400
+++ source-new/src/fork_exec/postfork.rs	2025-09-11 02:00:00.319001235 -0400
@@ -339,7 +339,9 @@
                             "', which is not an executable command."
                         );
                     }
-                } else if md.unwrap().mode() & u32::from(libc::S_IFMT) == u32::from(libc::S_IFDIR) {
+                } else if md.unwrap().mode() & u32::try_from(libc::S_IFMT).unwrap()
+                    == u32::try_from(libc::S_IFDIR).unwrap()
+                {
                     FLOG_SAFE!(
                         exec,
                         "Failed to execute process '",
diff '--color=auto' -ruwN source/src/input_common.rs source-new/src/input_common.rs
--- source/src/input_common.rs	2025-09-11 01:59:14.828576001 -0400
+++ source-new/src/input_common.rs	2025-09-11 02:00:00.316042380 -0400
@@ -589,7 +589,9 @@
     // pselect expects timeouts in nanoseconds.
     const NSEC_PER_MSEC: u64 = 1000 * 1000;
     const NSEC_PER_SEC: u64 = NSEC_PER_MSEC * 1000;
+    #[cfg(not(target_os = "redox"))]
     let wait_nsec: u64 = (timeout.as_millis() as u64) * NSEC_PER_MSEC;
+    #[cfg(not(target_os = "redox"))]
     let timeout = libc::timespec {
         tv_sec: (wait_nsec / NSEC_PER_SEC).try_into().unwrap(),
         tv_nsec: (wait_nsec % NSEC_PER_SEC).try_into().unwrap(),
@@ -605,6 +607,7 @@
         libc::FD_SET(in_fd, &mut fdset);
     }
 
+    #[cfg(not(target_os = "redox"))]
     let res = unsafe {
         libc::pselect(
             in_fd + 1,
@@ -616,6 +619,31 @@
         )
     };
 
+    #[cfg(target_os = "redox")]
+    let res = unsafe {
+        //HACK: pselect does this atomically
+        let mut saved = MaybeUninit::uninit();
+        let mut saved = {
+            libc::sigfillset(saved.as_mut_ptr());
+            saved.assume_init()
+        };
+        libc::sigprocmask(libc::SIG_SETMASK, &sigs, &mut saved);
+        let mut timeout = libc::timeval {
+            tv_sec: timeout.as_secs() as _,
+            tv_usec: timeout.subsec_micros() as _,
+        };
+        let res = libc::select(
+            in_fd + 1,
+            &mut fdset,
+            ptr::null_mut(),
+            ptr::null_mut(),
+            &raw mut timeout,
+        );
+        libc::sigprocmask(libc::SIG_SETMASK, &saved, ptr::null_mut());
+
+        res
+    };
+
     // Prevent signal starvation on WSL causing the `torn_escapes.py` test to fail
     if is_windows_subsystem_for_linux(WSL::V1) {
         // Merely querying the current thread's sigmask is sufficient to deliver a pending signal
diff '--color=auto' -ruwN source/src/libc.c source-new/src/libc.c
--- source/src/libc.c	2025-09-11 01:59:14.599514890 -0400
+++ source-new/src/libc.c	2025-09-11 02:00:00.304589636 -0400
@@ -4,7 +4,7 @@
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>     // MB_CUR_MAX
-#include <sys/mount.h>  // MNT_LOCAL
+/* #include <sys/mount.h>  // MNT_LOCAL */
 #include <sys/resource.h>
 #include <sys/statvfs.h>  // ST_LOCAL
 #include <unistd.h>       // _CS_PATH, _PC_CASE_SENSITIVE
diff '--color=auto' -ruwN source/src/path.rs source-new/src/path.rs
--- source/src/path.rs	2025-09-11 01:59:14.600515157 -0400
+++ source-new/src/path.rs	2025-09-11 02:00:00.317047039 -0400
@@ -738,7 +738,9 @@
             crate::libc::ST_LOCAL(),
             &narrow,
         );
-        #[cfg(not(target_os = "netbsd"))]
+        #[cfg(target_os = "redox")]
+        let remoteness = DirRemoteness::unknown;
+        #[cfg(not(target_os = "redox"))]
         let remoteness = remoteness_via_statfs(
             libc::statfs,
             |stat: &libc::statfs| stat.f_flags,