diff --git a/crates/host_env/src/errno_wasm.rs b/crates/host_env/src/errno_wasm.rs
new file mode 100644
index 000000000..1bf4922c1
--- /dev/null
+++ b/crates/host_env/src/errno_wasm.rs
@@ -0,0 +1,10 @@
+//! Errno numbers for `wasm32-unknown-unknown`.
+//!
+//! There is no libc errno table. The values are the Linux ABI the stdlib
+//! and `OSError` subclasses match against.
+
+pub mod errors {
+    pub const EAGAIN: i32 = 11;
+    pub const ECONNABORTED: i32 = 103;
+    pub const ECONNRESET: i32 = 104;
+}
diff --git a/crates/host_env/src/lib.rs b/crates/host_env/src/lib.rs
index f285771de..202f40456 100644
--- a/crates/host_env/src/lib.rs
+++ b/crates/host_env/src/lib.rs
@@ -9,6 +9,9 @@ pub use macros::*;
 pub mod ctypes;
 #[cfg(any(unix, windows, target_os = "wasi"))]
 pub mod errno;
+#[cfg(all(target_arch = "wasm32", target_os = "unknown"))]
+#[path = "errno_wasm.rs"]
+pub mod errno;
 #[cfg(any(unix, windows, target_os = "wasi"))]
 pub mod io;
 #[cfg(all(target_arch = "wasm32", not(target_os = "wasi")))]
@@ -44,6 +47,9 @@ pub mod fcntl;
 pub mod select;
 #[cfg(any(unix, windows))]
 pub mod socket;
+#[cfg(any(all(target_arch = "wasm32", target_os = "unknown"), target_os = "wasi"))]
+#[path = "socket_wasm.rs"]
+pub mod socket;
 #[cfg(unix)]
 pub mod syslog;
 #[cfg(all(unix, not(target_os = "redox"), not(target_os = "ios")))]
diff --git a/crates/host_env/src/os.rs b/crates/host_env/src/os.rs
index cdfced96c..ae3784ace 100644
--- a/crates/host_env/src/os.rs
+++ b/crates/host_env/src/os.rs
@@ -60,6 +60,42 @@ pub const SF_SUPPORTED: u32 = 0x009f0000;
 #[cfg(target_os = "macos")]
 pub const SF_SYNTHETIC: u32 = 0xc0000000;
 
+/// BSD `chflags` bits libc binds on macOS and `_stat.c` falls back to
+/// elsewhere. Published by `_stat` on every platform.
+#[cfg(target_os = "macos")]
+pub use libc::{
+    SF_APPEND, SF_ARCHIVED, SF_IMMUTABLE, UF_APPEND, UF_COMPRESSED, UF_HIDDEN, UF_IMMUTABLE,
+    UF_NODUMP, UF_OPAQUE,
+};
+#[cfg(not(target_os = "macos"))]
+pub const UF_NODUMP: u32 = 0x00000001;
+#[cfg(not(target_os = "macos"))]
+pub const UF_IMMUTABLE: u32 = 0x00000002;
+#[cfg(not(target_os = "macos"))]
+pub const UF_APPEND: u32 = 0x00000004;
+#[cfg(not(target_os = "macos"))]
+pub const UF_OPAQUE: u32 = 0x00000008;
+#[cfg(not(target_os = "macos"))]
+pub const UF_COMPRESSED: u32 = 0x00000020;
+#[cfg(not(target_os = "macos"))]
+pub const UF_HIDDEN: u32 = 0x00008000;
+#[cfg(not(target_os = "macos"))]
+pub const SF_ARCHIVED: u32 = 0x00010000;
+#[cfg(not(target_os = "macos"))]
+pub const SF_IMMUTABLE: u32 = 0x00020000;
+#[cfg(not(target_os = "macos"))]
+pub const SF_APPEND: u32 = 0x00040000;
+
+/// Solaris door/port and BSD whiteout. `_stat` publishes 0 where the
+/// platform has no such file type.
+pub const S_IFDOOR: u32 = 0;
+pub const S_IFPORT: u32 = 0;
+pub const S_IFWHT: u32 = if cfg!(target_os = "macos") {
+    0o160000
+} else {
+    0
+};
+
 #[cfg(not(any(unix, windows, target_os = "wasi")))]
 pub fn rename(
     from: impl AsRef<std::path::Path>,
diff --git a/crates/host_env/src/socket.rs b/crates/host_env/src/socket.rs
index 3c87b1851..dd9b47a2c 100644
--- a/crates/host_env/src/socket.rs
+++ b/crates/host_env/src/socket.rs
@@ -181,6 +181,88 @@ pub const CAN_BCM_RX_RTR_FRAME: i32 = 0x0400;
 #[cfg(target_os = "linux")]
 pub const CAN_BCM_CAN_FD_FRAME: i32 = 0x0800;
 
+/// `linux/vm_sockets.h`. libc does not bind the vsock sockopt / cid names.
+#[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))]
+pub const SO_VM_SOCKETS_BUFFER_SIZE: u32 = 0;
+#[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))]
+pub const SO_VM_SOCKETS_BUFFER_MIN_SIZE: u32 = 1;
+#[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))]
+pub const SO_VM_SOCKETS_BUFFER_MAX_SIZE: u32 = 2;
+#[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))]
+pub const VMADDR_CID_ANY: u32 = 0xffff_ffff;
+#[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))]
+pub const VMADDR_PORT_ANY: u32 = 0xffff_ffff;
+#[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))]
+pub const VMADDR_CID_HOST: u32 = 2;
+#[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))]
+pub const VM_SOCKETS_INVALID_VERSION: u32 = 0xffff_ffff;
+
+/// `netinet/udplite.h`. libc does not bind the coverage sockopts.
+#[cfg(any(
+    target_os = "android",
+    target_os = "fuchsia",
+    target_os = "freebsd",
+    target_os = "linux"
+))]
+pub const UDPLITE_SEND_CSCOV: i32 = 10;
+#[cfg(any(
+    target_os = "android",
+    target_os = "fuchsia",
+    target_os = "freebsd",
+    target_os = "linux"
+))]
+pub const UDPLITE_RECV_CSCOV: i32 = 11;
+
+/// `SOL_IP` / `SOL_UDP` when libc does not bind them. Linux takes the
+/// header names; Windows takes WinSock `SOL_IP`. Elsewhere they are the
+/// IANA protocol numbers.
+#[cfg(not(any(
+    target_os = "android",
+    target_os = "fuchsia",
+    target_os = "linux",
+    windows
+)))]
+pub const SOL_IP: i32 = 0;
+#[cfg(not(any(
+    target_os = "android",
+    target_os = "fuchsia",
+    target_os = "linux",
+    windows
+)))]
+pub const SOL_UDP: i32 = 17;
+
+/// `SOMAXCONN` when neither libc nor WinSock publishes it.
+#[cfg(not(any(
+    target_os = "android",
+    target_os = "dragonfly",
+    target_os = "freebsd",
+    target_os = "fuchsia",
+    target_os = "linux",
+    target_os = "netbsd",
+    target_os = "openbsd",
+    target_vendor = "apple",
+    windows
+)))]
+pub const SOMAXCONN: i32 = 5;
+
+/// Bluetooth wildcard / local addresses. Header strings, not libc names.
+#[cfg(any(
+    target_os = "android",
+    target_os = "freebsd",
+    target_os = "fuchsia",
+    target_os = "linux",
+    target_os = "openbsd"
+))]
+pub const BDADDR_ANY: &str = "00:00:00:00:00:00";
+#[cfg(any(
+    target_os = "android",
+    target_os = "freebsd",
+    target_os = "fuchsia",
+    target_os = "linux",
+    target_os = "openbsd"
+))]
+pub const BDADDR_LOCAL: &str = "00:00:00:FF:FF:FF";
+
 /// RFC 3542 IPv6 socket options (`netinet6/in6.h`). Not in libc.
 #[cfg(target_vendor = "apple")]
 pub const IPV6_RECVHOPLIMIT: i32 = 37;
diff --git a/crates/host_env/src/socket_wasm.rs b/crates/host_env/src/socket_wasm.rs
new file mode 100644
index 000000000..05c784322
--- /dev/null
+++ b/crates/host_env/src/socket_wasm.rs
@@ -0,0 +1,57 @@
+//! Socket constant surface for `wasm32-unknown-unknown` and WASI.
+//!
+//! There are no BSD sockets on unknown-unknown, and WASI does not use the
+//! unix/windows socket engine yet. The numbers are the Linux ABI
+//! `Lib/socket.py` expects so the stdlib can import.
+
+pub const AF_UNSPEC: i32 = 0;
+pub const AF_UNIX: i32 = 1;
+pub const AF_INET: i32 = 2;
+pub const AF_INET6: i32 = 10;
+
+pub const SOCK_STREAM: i32 = 1;
+pub const SOCK_DGRAM: i32 = 2;
+pub const SOCK_RAW: i32 = 3;
+
+pub const SOL_SOCKET: i32 = 1;
+pub const SO_REUSEADDR: i32 = 2;
+pub const SO_TYPE: i32 = 3;
+pub const SO_ERROR: i32 = 4;
+pub const SO_BROADCAST: i32 = 6;
+pub const SO_KEEPALIVE: i32 = 9;
+pub const SO_RCVBUF: i32 = 8;
+pub const SO_SNDBUF: i32 = 7;
+
+pub const IPPROTO_IP: i32 = 0;
+pub const IPPROTO_TCP: i32 = 6;
+pub const IPPROTO_UDP: i32 = 17;
+pub const IPPROTO_IPV6: i32 = 41;
+pub const SOL_TCP: i32 = IPPROTO_TCP;
+
+pub const SHUT_RD: i32 = 0;
+pub const SHUT_WR: i32 = 1;
+pub const SHUT_RDWR: i32 = 2;
+
+pub const MSG_OOB: i32 = 1;
+pub const MSG_PEEK: i32 = 2;
+pub const MSG_DONTROUTE: i32 = 4;
+
+pub const AI_PASSIVE: i32 = 1;
+pub const AI_CANONNAME: i32 = 2;
+pub const AI_NUMERICHOST: i32 = 4;
+pub const AI_NUMERICSERV: i32 = 8;
+pub const AI_ADDRCONFIG: i32 = 32;
+
+pub const NI_NUMERICHOST: i32 = 1;
+pub const NI_NUMERICSERV: i32 = 2;
+pub const NI_NOFQDN: i32 = 4;
+pub const NI_NAMEREQD: i32 = 8;
+pub const NI_DGRAM: i32 = 16;
+
+pub const INADDR_ANY: u32 = 0;
+pub const INADDR_LOOPBACK: u32 = 0x7f00_0001;
+pub const INADDR_BROADCAST: u32 = 0xffff_ffff;
+pub const INADDR_NONE: u32 = 0xffff_ffff;
+pub const IPPORT_RESERVED: i32 = 1024;
+pub const IPPORT_USERRESERVED: i32 = 5000;
+pub const TCP_NODELAY: i32 = 1;
diff --git a/crates/stdlib/src/lib.rs b/crates/stdlib/src/lib.rs
index 68dcf0b69..070685d0c 100644
--- a/crates/stdlib/src/lib.rs
+++ b/crates/stdlib/src/lib.rs
@@ -65,10 +65,13 @@ mod suggestions;
 
 // TODO: maybe make this an extension module, if we ever get those
 // mod re;
-#[cfg(all(feature = "host_env", not(target_arch = "wasm32")))]
+#[cfg(all(
+    feature = "host_env",
+    not(any(all(target_arch = "wasm32", target_os = "unknown"), target_os = "wasi"))
+))]
 pub mod socket;
 
-#[cfg(target_arch = "wasm32")]
+#[cfg(any(all(target_arch = "wasm32", target_os = "unknown"), target_os = "wasi"))]
 #[path = "socket_wasm.rs"]
 pub mod socket;
 
@@ -267,9 +270,12 @@ pub fn stdlib_module_defs(ctx: &Context) -> Vec<&'static builtins::PyModuleDef>
         sha256::module_def(ctx),
         sha3::module_def(ctx),
         sha512::module_def(ctx),
-        #[cfg(all(feature = "host_env", not(target_arch = "wasm32")))]
+        #[cfg(all(
+            feature = "host_env",
+            not(any(all(target_arch = "wasm32", target_os = "unknown"), target_os = "wasi"))
+        ))]
         socket::module_def(ctx),
-        #[cfg(target_arch = "wasm32")]
+        #[cfg(any(all(target_arch = "wasm32", target_os = "unknown"), target_os = "wasi"))]
         socket::module_def(ctx),
         #[cfg(all(
             feature = "sqlite",
diff --git a/crates/stdlib/src/openssl.rs b/crates/stdlib/src/openssl.rs
index 8c3f5f9c7..026c99f19 100644
--- a/crates/stdlib/src/openssl.rs
+++ b/crates/stdlib/src/openssl.rs
@@ -136,62 +136,27 @@ mod _ssl {
         X509_V_FLAG_X509_STRICT as VERIFY_X509_STRICT,
     };
 
-    // SSL Alert Descriptions (RFC 5246 and extensions)
-    // Hybrid approach: use openssl_sys constants where available, hardcode others
     #[pyattr]
-    const ALERT_DESCRIPTION_CLOSE_NOTIFY: core::ffi::c_int = 0;
-    #[pyattr]
-    const ALERT_DESCRIPTION_UNEXPECTED_MESSAGE: core::ffi::c_int = 10;
-    #[pyattr]
-    const ALERT_DESCRIPTION_BAD_RECORD_MAC: core::ffi::c_int = 20;
-    #[pyattr]
-    const ALERT_DESCRIPTION_RECORD_OVERFLOW: core::ffi::c_int = 22;
-    #[pyattr]
-    const ALERT_DESCRIPTION_DECOMPRESSION_FAILURE: core::ffi::c_int = 30;
-    #[pyattr]
-    const ALERT_DESCRIPTION_HANDSHAKE_FAILURE: core::ffi::c_int = 40;
-    #[pyattr]
-    const ALERT_DESCRIPTION_BAD_CERTIFICATE: core::ffi::c_int = 42;
-    #[pyattr]
-    const ALERT_DESCRIPTION_UNSUPPORTED_CERTIFICATE: core::ffi::c_int = 43;
-    #[pyattr]
-    const ALERT_DESCRIPTION_CERTIFICATE_REVOKED: core::ffi::c_int = 44;
-    #[pyattr]
-    const ALERT_DESCRIPTION_CERTIFICATE_EXPIRED: core::ffi::c_int = 45;
-    #[pyattr]
-    const ALERT_DESCRIPTION_CERTIFICATE_UNKNOWN: core::ffi::c_int = 46;
-    #[pyattr]
-    const ALERT_DESCRIPTION_ILLEGAL_PARAMETER: core::ffi::c_int = SSL_AD_ILLEGAL_PARAMETER;
-    #[pyattr]
-    const ALERT_DESCRIPTION_UNKNOWN_CA: core::ffi::c_int = 48;
-    #[pyattr]
-    const ALERT_DESCRIPTION_ACCESS_DENIED: core::ffi::c_int = 49;
-    #[pyattr]
-    const ALERT_DESCRIPTION_DECODE_ERROR: core::ffi::c_int = SSL_AD_DECODE_ERROR;
-    #[pyattr]
-    const ALERT_DESCRIPTION_DECRYPT_ERROR: core::ffi::c_int = 51;
-    #[pyattr]
-    const ALERT_DESCRIPTION_PROTOCOL_VERSION: core::ffi::c_int = 70;
-    #[pyattr]
-    const ALERT_DESCRIPTION_INSUFFICIENT_SECURITY: core::ffi::c_int = 71;
-    #[pyattr]
-    const ALERT_DESCRIPTION_INTERNAL_ERROR: core::ffi::c_int = 80;
-    #[pyattr]
-    const ALERT_DESCRIPTION_USER_CANCELLED: core::ffi::c_int = 90;
-    #[pyattr]
-    const ALERT_DESCRIPTION_NO_RENEGOTIATION: core::ffi::c_int = 100;
-    #[pyattr]
-    const ALERT_DESCRIPTION_UNSUPPORTED_EXTENSION: core::ffi::c_int = 110;
-    #[pyattr]
-    const ALERT_DESCRIPTION_CERTIFICATE_UNOBTAINABLE: core::ffi::c_int = 111;
-    #[pyattr]
-    const ALERT_DESCRIPTION_UNRECOGNIZED_NAME: core::ffi::c_int = SSL_AD_UNRECOGNIZED_NAME;
-    #[pyattr]
-    const ALERT_DESCRIPTION_BAD_CERTIFICATE_STATUS_RESPONSE: core::ffi::c_int = 113;
-    #[pyattr]
-    const ALERT_DESCRIPTION_BAD_CERTIFICATE_HASH_VALUE: core::ffi::c_int = 114;
-    #[pyattr]
-    const ALERT_DESCRIPTION_UNKNOWN_PSK_IDENTITY: core::ffi::c_int = 115;
+    use rustpython_host_env::ssl::{
+        ALERT_DESCRIPTION_ACCESS_DENIED, ALERT_DESCRIPTION_BAD_CERTIFICATE,
+        ALERT_DESCRIPTION_BAD_CERTIFICATE_HASH_VALUE,
+        ALERT_DESCRIPTION_BAD_CERTIFICATE_STATUS_RESPONSE, ALERT_DESCRIPTION_BAD_RECORD_MAC,
+        ALERT_DESCRIPTION_CERTIFICATE_EXPIRED, ALERT_DESCRIPTION_CERTIFICATE_REQUIRED,
+        ALERT_DESCRIPTION_CERTIFICATE_REVOKED, ALERT_DESCRIPTION_CERTIFICATE_UNKNOWN,
+        ALERT_DESCRIPTION_CERTIFICATE_UNOBTAINABLE, ALERT_DESCRIPTION_CLOSE_NOTIFY,
+        ALERT_DESCRIPTION_DECODE_ERROR, ALERT_DESCRIPTION_DECOMPRESSION_FAILURE,
+        ALERT_DESCRIPTION_DECRYPT_ERROR, ALERT_DESCRIPTION_DECRYPTION_FAILED,
+        ALERT_DESCRIPTION_EXPORT_RESTRICTION, ALERT_DESCRIPTION_HANDSHAKE_FAILURE,
+        ALERT_DESCRIPTION_ILLEGAL_PARAMETER, ALERT_DESCRIPTION_INAPPROPRIATE_FALLBACK,
+        ALERT_DESCRIPTION_INSUFFICIENT_SECURITY, ALERT_DESCRIPTION_INTERNAL_ERROR,
+        ALERT_DESCRIPTION_MISSING_EXTENSION, ALERT_DESCRIPTION_NO_APPLICATION_PROTOCOL,
+        ALERT_DESCRIPTION_NO_CERTIFICATE, ALERT_DESCRIPTION_NO_RENEGOTIATION,
+        ALERT_DESCRIPTION_PROTOCOL_VERSION, ALERT_DESCRIPTION_RECORD_OVERFLOW,
+        ALERT_DESCRIPTION_UNEXPECTED_MESSAGE, ALERT_DESCRIPTION_UNKNOWN_CA,
+        ALERT_DESCRIPTION_UNKNOWN_PSK_IDENTITY, ALERT_DESCRIPTION_UNRECOGNIZED_NAME,
+        ALERT_DESCRIPTION_UNSUPPORTED_CERTIFICATE, ALERT_DESCRIPTION_UNSUPPORTED_EXTENSION,
+        ALERT_DESCRIPTION_USER_CANCELLED,
+    };
 
     // CRL verification constants
     #[pyattr]
diff --git a/crates/stdlib/src/socket.rs b/crates/stdlib/src/socket.rs
index 26f6e96ad..e4bd8d501 100644
--- a/crates/stdlib/src/socket.rs
+++ b/crates/stdlib/src/socket.rs
@@ -262,40 +262,12 @@ mod _socket {
         TCP_SYNCNT, TCP_WINDOW_CLAMP,
     };
 
-    // gated on presence of AF_VSOCK:
     #[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))]
     #[pyattr]
-    const SO_VM_SOCKETS_BUFFER_SIZE: u32 = 0;
-
-    // gated on presence of AF_VSOCK:
-    #[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))]
-    #[pyattr]
-    const SO_VM_SOCKETS_BUFFER_MIN_SIZE: u32 = 1;
-
-    // gated on presence of AF_VSOCK:
-    #[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))]
-    #[pyattr]
-    const SO_VM_SOCKETS_BUFFER_MAX_SIZE: u32 = 2;
-
-    // gated on presence of AF_VSOCK:
-    #[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))]
-    #[pyattr]
-    const VMADDR_CID_ANY: u32 = 0xffffffff; // 0xffffffff
-
-    // gated on presence of AF_VSOCK:
-    #[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))]
-    #[pyattr]
-    const VMADDR_PORT_ANY: u32 = 0xffffffff; // 0xffffffff
-
-    // gated on presence of AF_VSOCK:
-    #[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))]
-    #[pyattr]
-    const VMADDR_CID_HOST: u32 = 2;
-
-    // gated on presence of AF_VSOCK:
-    #[cfg(any(target_os = "android", target_os = "fuchsia", target_os = "linux"))]
-    #[pyattr]
-    const VM_SOCKETS_INVALID_VERSION: u32 = 0xffffffff; // 0xffffffff
+    use host_socket::{
+        SO_VM_SOCKETS_BUFFER_MAX_SIZE, SO_VM_SOCKETS_BUFFER_MIN_SIZE, SO_VM_SOCKETS_BUFFER_SIZE,
+        VM_SOCKETS_INVALID_VERSION, VMADDR_CID_ANY, VMADDR_CID_HOST, VMADDR_PORT_ANY,
+    };
 
     // TODO: gated on https://github.com/rust-lang/libc/pull/1662
     // // gated on presence of AF_VSOCK:
@@ -307,11 +279,7 @@ mod _socket {
 
     #[cfg(not(any(target_os = "android", target_os = "fuchsia", target_os = "linux")))]
     #[pyattr]
-    const SOL_IP: i32 = 0;
-
-    #[cfg(not(any(target_os = "android", target_os = "fuchsia", target_os = "linux")))]
-    #[pyattr]
-    const SOL_UDP: i32 = 17;
+    use host_socket::{SOL_IP, SOL_UDP};
 
     #[cfg(any(target_os = "android", target_os = "linux", windows))]
     #[pyattr]
@@ -345,16 +313,7 @@ mod _socket {
         target_os = "linux"
     ))]
     #[pyattr]
-    const UDPLITE_SEND_CSCOV: i32 = 10;
-
-    #[cfg(any(
-        target_os = "android",
-        target_os = "fuchsia",
-        target_os = "freebsd",
-        target_os = "linux"
-    ))]
-    #[pyattr]
-    const UDPLITE_RECV_CSCOV: i32 = 11;
+    use host_socket::{UDPLITE_RECV_CSCOV, UDPLITE_SEND_CSCOV};
 
     #[cfg(any(
         target_os = "android",
@@ -693,7 +652,7 @@ mod _socket {
         windows
     )))]
     #[pyattr]
-    const SOMAXCONN: i32 = 5; // Common value
+    use host_socket::SOMAXCONN;
 
     // HERE IS WHERE THE BLUETOOTH CONSTANTS START
     // TODO: there should be a more intelligent way of detecting bluetooth on a platform.
@@ -716,16 +675,7 @@ mod _socket {
         target_os = "openbsd"
     ))]
     #[pyattr]
-    const BDADDR_ANY: &str = "00:00:00:00:00:00";
-    #[cfg(any(
-        target_os = "android",
-        target_os = "freebsd",
-        target_os = "fuchsia",
-        target_os = "linux",
-        target_os = "openbsd"
-    ))]
-    #[pyattr]
-    const BDADDR_LOCAL: &str = "00:00:00:FF:FF:FF";
+    use host_socket::{BDADDR_ANY, BDADDR_LOCAL};
     // HERE IS WHERE THE BLUETOOTH CONSTANTS END
 
     #[cfg(windows)]
diff --git a/crates/stdlib/src/socket_wasm.rs b/crates/stdlib/src/socket_wasm.rs
index df9bc75f9..085785965 100644
--- a/crates/stdlib/src/socket_wasm.rs
+++ b/crates/stdlib/src/socket_wasm.rs
@@ -20,99 +20,15 @@ mod _socket {
     use std::sync::atomic::{AtomicI32, AtomicU64, Ordering};
 
     #[pyattr]
-    const AF_UNSPEC: i32 = 0;
-    #[pyattr]
-    const AF_UNIX: i32 = 1;
-    #[pyattr]
-    const AF_INET: i32 = 2;
-    #[pyattr]
-    const AF_INET6: i32 = 10;
-
-    #[pyattr]
-    const SOCK_STREAM: i32 = 1;
-    #[pyattr]
-    const SOCK_DGRAM: i32 = 2;
-    #[pyattr]
-    const SOCK_RAW: i32 = 3;
-
-    #[pyattr]
-    const SOL_SOCKET: i32 = 1;
-    #[pyattr]
-    const SO_REUSEADDR: i32 = 2;
-    #[pyattr]
-    const SO_TYPE: i32 = 3;
-    #[pyattr]
-    const SO_ERROR: i32 = 4;
-    #[pyattr]
-    const SO_BROADCAST: i32 = 6;
-    #[pyattr]
-    const SO_KEEPALIVE: i32 = 9;
-    #[pyattr]
-    const SO_RCVBUF: i32 = 8;
-    #[pyattr]
-    const SO_SNDBUF: i32 = 7;
-
-    #[pyattr]
-    const IPPROTO_IP: i32 = 0;
-    #[pyattr]
-    const IPPROTO_TCP: i32 = 6;
-    #[pyattr]
-    const IPPROTO_UDP: i32 = 17;
-    #[pyattr]
-    const IPPROTO_IPV6: i32 = 41;
-    #[pyattr]
-    const SOL_TCP: i32 = IPPROTO_TCP;
-
-    #[pyattr]
-    const SHUT_RD: i32 = 0;
-    #[pyattr]
-    const SHUT_WR: i32 = 1;
-    #[pyattr]
-    const SHUT_RDWR: i32 = 2;
-
-    #[pyattr]
-    const MSG_OOB: i32 = 1;
-    #[pyattr]
-    const MSG_PEEK: i32 = 2;
-    #[pyattr]
-    const MSG_DONTROUTE: i32 = 4;
-
-    #[pyattr]
-    const AI_PASSIVE: i32 = 1;
-    #[pyattr]
-    const AI_CANONNAME: i32 = 2;
-    #[pyattr]
-    const AI_NUMERICHOST: i32 = 4;
-    #[pyattr]
-    const AI_NUMERICSERV: i32 = 8;
-    #[pyattr]
-    const AI_ADDRCONFIG: i32 = 32;
-
-    #[pyattr]
-    const NI_NUMERICHOST: i32 = 1;
-    #[pyattr]
-    const NI_NUMERICSERV: i32 = 2;
-    #[pyattr]
-    const NI_NOFQDN: i32 = 4;
-    #[pyattr]
-    const NI_NAMEREQD: i32 = 8;
-    #[pyattr]
-    const NI_DGRAM: i32 = 16;
-
-    #[pyattr]
-    const INADDR_ANY: u32 = 0;
-    #[pyattr]
-    const INADDR_LOOPBACK: u32 = 0x7f00_0001;
-    #[pyattr]
-    const INADDR_BROADCAST: u32 = 0xffff_ffff;
-    #[pyattr]
-    const INADDR_NONE: u32 = 0xffff_ffff;
-    #[pyattr]
-    const IPPORT_RESERVED: i32 = 1024;
-    #[pyattr]
-    const IPPORT_USERRESERVED: i32 = 5000;
-    #[pyattr]
-    const TCP_NODELAY: i32 = 1;
+    use rustpython_host_env::socket::{
+        AF_INET, AF_INET6, AF_UNIX, AF_UNSPEC, AI_ADDRCONFIG, AI_CANONNAME, AI_NUMERICHOST,
+        AI_NUMERICSERV, AI_PASSIVE, INADDR_ANY, INADDR_BROADCAST, INADDR_LOOPBACK, INADDR_NONE,
+        IPPORT_RESERVED, IPPORT_USERRESERVED, IPPROTO_IP, IPPROTO_IPV6, IPPROTO_TCP, IPPROTO_UDP,
+        MSG_DONTROUTE, MSG_OOB, MSG_PEEK, NI_DGRAM, NI_NAMEREQD, NI_NOFQDN, NI_NUMERICHOST,
+        NI_NUMERICSERV, SHUT_RD, SHUT_RDWR, SHUT_WR, SO_BROADCAST, SO_ERROR, SO_KEEPALIVE,
+        SO_RCVBUF, SO_REUSEADDR, SO_SNDBUF, SO_TYPE, SOCK_DGRAM, SOCK_RAW, SOCK_STREAM, SOL_SOCKET,
+        SOL_TCP, TCP_NODELAY,
+    };
     #[pyattr(name = "has_ipv6")]
     const HAS_IPV6: bool = true;
 
diff --git a/crates/vm/src/stdlib/_io.rs b/crates/vm/src/stdlib/_io.rs
index 5abf2cdaa..6195f501d 100644
--- a/crates/vm/src/stdlib/_io.rs
+++ b/crates/vm/src/stdlib/_io.rs
@@ -15,7 +15,7 @@ cfg_select! {
     _ => {
         type Offset = i64;
         // EAGAIN constant for BlockingIOError
-        const EAGAIN: i32 = 11; // Standard POSIX value
+        const EAGAIN: i32 = rustpython_host_env::errno::errors::EAGAIN;
     }
 }
 
diff --git a/crates/vm/src/stdlib/_stat.rs b/crates/vm/src/stdlib/_stat.rs
index f105aad94..b8533555b 100644
--- a/crates/vm/src/stdlib/_stat.rs
+++ b/crates/vm/src/stdlib/_stat.rs
@@ -84,20 +84,13 @@ mod _stat {
     );
 
     #[pyattr]
-    pub const S_IFDOOR: Mode = 0; // TODO: RUSTPYTHON Support Solaris
+    pub const S_IFDOOR: Mode = rustpython_host_env::os::S_IFDOOR as Mode;
 
     #[pyattr]
-    pub const S_IFPORT: Mode = 0; // TODO: RUSTPYTHON Support Solaris
-
-    // TODO: RUSTPYTHON Support BSD
-    // https://man.freebsd.org/cgi/man.cgi?stat(2)
+    pub const S_IFPORT: Mode = rustpython_host_env::os::S_IFPORT as Mode;
 
     #[pyattr]
-    pub const S_IFWHT: Mode = if cfg!(target_os = "macos") {
-        0o160000
-    } else {
-        0
-    };
+    pub const S_IFWHT: Mode = rustpython_host_env::os::S_IFWHT as Mode;
 
     // Permission bits
 
@@ -255,73 +248,11 @@ mod _stat {
 
     // Unix file flags (if on Unix)
 
-    #[pyattr]
-    pub const UF_NODUMP: u32 = libc_const!(
-        #[cfg(target_os = "macos")]
-        UF_NODUMP,
-        0x00000001
-    );
-
-    #[pyattr]
-    pub const UF_IMMUTABLE: u32 = libc_const!(
-        #[cfg(target_os = "macos")]
-        UF_IMMUTABLE,
-        0x00000002
-    );
-
-    #[pyattr]
-    pub const UF_APPEND: u32 = libc_const!(
-        #[cfg(target_os = "macos")]
-        UF_APPEND,
-        0x00000004
-    );
-
-    #[pyattr]
-    pub const UF_OPAQUE: u32 = libc_const!(
-        #[cfg(target_os = "macos")]
-        UF_OPAQUE,
-        0x00000008
-    );
-
-    #[pyattr]
-    pub const UF_COMPRESSED: u32 = libc_const!(
-        #[cfg(target_os = "macos")]
-        UF_COMPRESSED,
-        0x00000020
-    );
-
-    #[pyattr]
-    pub const UF_HIDDEN: u32 = libc_const!(
-        #[cfg(target_os = "macos")]
-        UF_HIDDEN,
-        0x00008000
-    );
-
-    #[pyattr]
-    pub const SF_ARCHIVED: u32 = libc_const!(
-        #[cfg(target_os = "macos")]
-        SF_ARCHIVED,
-        0x00010000
-    );
-
-    #[pyattr]
-    pub const SF_IMMUTABLE: u32 = libc_const!(
-        #[cfg(target_os = "macos")]
-        SF_IMMUTABLE,
-        0x00020000
-    );
-
-    #[pyattr]
-    pub const SF_APPEND: u32 = libc_const!(
-        #[cfg(target_os = "macos")]
-        SF_APPEND,
-        0x00040000
-    );
-
     #[pyattr]
     pub use rustpython_host_env::os::{
-        SF_DATALESS, SF_FIRMLINK, SF_NOUNLINK, SF_SETTABLE, SF_SNAPSHOT, UF_DATAVAULT, UF_NOUNLINK,
-        UF_SETTABLE, UF_TRACKED,
+        SF_APPEND, SF_ARCHIVED, SF_DATALESS, SF_FIRMLINK, SF_IMMUTABLE, SF_NOUNLINK, SF_SETTABLE,
+        SF_SNAPSHOT, UF_APPEND, UF_COMPRESSED, UF_DATAVAULT, UF_HIDDEN, UF_IMMUTABLE, UF_NODUMP,
+        UF_NOUNLINK, UF_OPAQUE, UF_SETTABLE, UF_TRACKED,
     };
 
     #[cfg(target_os = "macos")]
diff --git a/crates/vm/src/stdlib/errno.rs b/crates/vm/src/stdlib/errno.rs
index 8327a3a98..0921ebac6 100644
--- a/crates/vm/src/stdlib/errno.rs
+++ b/crates/vm/src/stdlib/errno.rs
@@ -23,15 +23,8 @@ mod errno_mod {
     }
 }
 
-#[cfg(any(unix, windows, target_os = "wasi"))]
 pub use rustpython_host_env::errno::errors;
 
-#[cfg(all(target_arch = "wasm32", not(target_os = "wasi")))]
-pub mod errors {
-    pub const ECONNABORTED: i32 = 103;
-    pub const ECONNRESET: i32 = 104;
-}
-
 #[cfg(any(unix, windows, target_os = "wasi"))]
 macro_rules! e {
     ($name:ident) => {