Add darwin build support

crates/rbitcoin-store/Cargo.toml

@@ -14,8 +14,6 @@ rbitcoin-log = { workspace = true }
 bitcoin_hashes = { workspace = true }
 # fallocate / punch-hole for multi‑GiB grows without zero-fill storms (Linux).
 libc = "0.2"
-# Bulk pread submission for head-resolve / confirm body load (Linux).
-io-uring = "0.7"
 # Datadir store.secret CSPRNG.
 getrandom = "0.2"
 # Sealed segment binary fuse8 (~9 bits/key).
@@ -24,6 +22,11 @@ bincode = { workspace = true }
 # Product bin only (store_bench); library tests keep the platform allocator.
 mimalloc = { workspace = true }
 
+# Bulk pread submission for head-resolve / confirm body load. Linux-only crate;
+# all uses in src are #[cfg(target_os = "linux")]-gated with darwin fallbacks.
+[target.'cfg(target_os = "linux")'.dependencies]
+io-uring = "0.7"
+
 [[bin]]
 name = "rbitcoin-store-bench"
 path = "src/bin/store_bench.rs"

crates/rbitcoin-store/src/bulk_io.rs

@@ -33,6 +33,7 @@ use std::os::fd::RawFd;
 use std::sync::atomic::{AtomicBool, AtomicU8, AtomicUsize, Ordering};
 
 /// SQ/CQ depth for bulk batch sessions.
+#[cfg(target_os = "linux")]
 const RING_ENTRIES: u32 = crate::uring_session::DEFAULT_ENTRIES;
 
 /// One independent pread. Caller owns `buf` for the full submit/wait.
@@ -43,6 +44,8 @@ pub struct ReadOp<'a> {
     /// Filled: bytes read (≥0) or negated errno on failure.
     pub result: i32,
     /// When true, SQE uses [`crate::uring_session::RWF_DONTCACHE`].
+    // Only read on the Linux io_uring submit path.
+    #[cfg_attr(not(target_os = "linux"), allow(dead_code))]
     pub dontcache: bool,
 }
 
@@ -54,6 +57,8 @@ pub struct WriteOp<'a> {
     /// Filled: bytes written (≥0) or negated errno on failure.
     pub result: i32,
     /// When true, SQE uses [`crate::uring_session::RWF_DONTCACHE`].
+    // Only read on the Linux io_uring submit path.
+    #[cfg_attr(not(target_os = "linux"), allow(dead_code))]
     pub dontcache: bool,
 }
 

crates/rbitcoin-store/src/uring_session.rs

@@ -15,6 +15,7 @@
 
 use crate::error::StoreError;
 use std::os::fd::RawFd;
+#[cfg(target_os = "linux")]
 use std::path::Path;
 
 /// Default SQ/CQ depth for all store io_uring sessions (bulk, plan head-resolve,

flake.nix

@@ -15,6 +15,8 @@
       systems = [
         "x86_64-linux"
         "aarch64-linux"
+        "x86_64-darwin"
+        "aarch64-darwin"
       ];
       forAllSystems = nixpkgs.lib.genAttrs systems;
 
@@ -34,19 +36,23 @@
             config = { };
             overlays = [ ];
           };
-          # Optional dynamic glibc package (Nix-store linked; not portable off-store).
-          rbitcoin-glibc = mkRbitcoin pkgs;
-          # Primary / default: fully static musl — portable operator binary.
-          rbitcoin-musl = mkRbitcoin pkgs.pkgsStatic;
+          isLinux = nixpkgs.lib.hasSuffix "-linux" system;
+          # Native build (Nix-store linked): glibc on Linux, plain darwin stdenv on macOS.
+          rbitcoin-native = mkRbitcoin pkgs;
+          # Primary / default on Linux: fully static musl — portable operator binary.
+          # musl is Linux-only, so darwin defaults to the native build instead.
+          rbitcoin-default = if isLinux then mkRbitcoin pkgs.pkgsStatic else rbitcoin-native;
         in
         {
-          default = rbitcoin-musl;
-          rbitcoin = rbitcoin-musl;
-          rbitcoin-node = rbitcoin-musl;
-          rbitcoin-cli = rbitcoin-musl;
-          rbitcoin-musl = rbitcoin-musl;
+          default = rbitcoin-default;
+          rbitcoin = rbitcoin-default;
+          rbitcoin-node = rbitcoin-default;
+          rbitcoin-cli = rbitcoin-default;
+        }
+        // nixpkgs.lib.optionalAttrs isLinux {
+          rbitcoin-musl = rbitcoin-default;
           # Kept for store-native Nix environments / optional dual-platform repro.
-          rbitcoin-glibc = rbitcoin-glibc;
+          rbitcoin-glibc = rbitcoin-native;
         }
         // nixpkgs.lib.optionalAttrs (system == "x86_64-linux") {
           # Optional third platform: aarch64-linux cross from x86_64 (heavy toolchain).
@@ -103,7 +109,8 @@
       checks = forAllSystems (
         system:
         {
-          rbitcoin = self.packages.${system}.rbitcoin-musl;
+          # musl on Linux, native on darwin — matches the default package.
+          rbitcoin = self.packages.${system}.default;
         }
       );
     };

nix/rbitcoin.nix

@@ -114,7 +114,7 @@ let
           asl20
         ];
         mainProgram = "rbitcoin-node";
-        platforms = platforms.linux;
+        platforms = platforms.linux ++ platforms.darwin;
       };
     }
   );