diff --git a/barretenberg/cpp/bootstrap.sh b/barretenberg/cpp/bootstrap.sh
index 75fb18d14f44..f9b8e536cf89 100755
--- a/barretenberg/cpp/bootstrap.sh
+++ b/barretenberg/cpp/bootstrap.sh
@@ -34,6 +34,10 @@ function inject_version {
   # Version starts immediately after the sentinel
   local version_offset=$((sentinel_offset + ${#sentinel}))
   printf "$version\0" | dd of="$binary" bs=1 seek=$version_offset conv=notrunc 2>/dev/null
+  # Re-sign on macOS after modifying the binary (version injection invalidates code signature)
+  if [[ "$(uname)" == "Darwin" ]]; then
+    codesign -s - -f "$binary" 2>/dev/null || true
+  fi
 }
 
 # Define build commands for each preset
diff --git a/barretenberg/cpp/src/barretenberg/bb/CMakeLists.txt b/barretenberg/cpp/src/barretenberg/bb/CMakeLists.txt
index c3858e2dded9..0bf527c0ba9f 100644
--- a/barretenberg/cpp/src/barretenberg/bb/CMakeLists.txt
+++ b/barretenberg/cpp/src/barretenberg/bb/CMakeLists.txt
@@ -21,6 +21,9 @@ if (NOT(FUZZING))
     # Link avm_transpiler when library is provided
     if(AVM_TRANSPILER_LIB)
         target_link_libraries(bb PRIVATE ${AVM_TRANSPILER_LIB})
+        if(APPLE)
+            target_link_libraries(bb PRIVATE "-framework CoreFoundation")
+        endif()
     endif()
     if(NOT WASM)
         target_link_libraries(bb PRIVATE ipc)
@@ -38,6 +41,14 @@ if (NOT(FUZZING))
         )
     endif()
 
+    # Re-sign on macOS to fix invalid linker-generated adhoc signature
+    if(APPLE)
+        add_custom_command(TARGET bb POST_BUILD
+            COMMAND codesign -s - -f $<TARGET_FILE:bb>
+            COMMENT "Re-signing bb binary for macOS"
+        )
+    endif()
+
     if(AVM)
         # Full bb-avm binary with AVM support (opt-in)
         add_executable(
@@ -61,6 +72,9 @@ if (NOT(FUZZING))
         # Link avm_transpiler when library is provided
         if(AVM_TRANSPILER_LIB)
             target_link_libraries(bb-avm PRIVATE ${AVM_TRANSPILER_LIB})
+            if(APPLE)
+                target_link_libraries(bb-avm PRIVATE "-framework CoreFoundation")
+            endif()
         endif()
         if(NOT WASM)
             target_link_libraries(bb-avm PRIVATE ipc)
@@ -77,5 +91,13 @@ if (NOT(FUZZING))
                 -ldw -lelf
             )
         endif()
+
+        # Re-sign on macOS to fix invalid linker-generated adhoc signature
+        if(APPLE)
+            add_custom_command(TARGET bb-avm POST_BUILD
+                COMMAND codesign -s - -f $<TARGET_FILE:bb-avm>
+                COMMENT "Re-signing bb-avm binary for macOS"
+            )
+        endif()
     endif()
 endif()
diff --git a/barretenberg/cpp/src/barretenberg/world_state/world_state.test.cpp b/barretenberg/cpp/src/barretenberg/world_state/world_state.test.cpp
index 3411d5d2e71d..6d6b1c882e68 100644
--- a/barretenberg/cpp/src/barretenberg/world_state/world_state.test.cpp
+++ b/barretenberg/cpp/src/barretenberg/world_state/world_state.test.cpp
@@ -492,9 +492,9 @@ TEST_F(WorldStateTest, NullifierBatchInsert)
     auto response = ws.batch_insert_indexed_leaves<NullifierLeafValue>(
         MerkleTreeId::NULLIFIER_TREE, { NullifierLeafValue(150), NullifierLeafValue(142), NullifierLeafValue(180) }, 2);
 
-    std::vector<std::pair<NullifierLeafValue, size_t>> expected_sorted_leaves = { { NullifierLeafValue(180), 2 },
-                                                                                  { NullifierLeafValue(150), 0 },
-                                                                                  { NullifierLeafValue(142), 1 } };
+    std::vector<std::pair<NullifierLeafValue, index_t>> expected_sorted_leaves = { { NullifierLeafValue(180), 2 },
+                                                                                   { NullifierLeafValue(150), 0 },
+                                                                                   { NullifierLeafValue(142), 1 } };
     EXPECT_EQ(response.sorted_leaves, expected_sorted_leaves);
 
     {
diff --git a/barretenberg/crs/bootstrap.sh b/barretenberg/crs/bootstrap.sh
index c2502e3621cd..3fdbfb1ce634 100755
--- a/barretenberg/crs/bootstrap.sh
+++ b/barretenberg/crs/bootstrap.sh
@@ -12,7 +12,16 @@ function build {
   crs_size_bytes=$((crs_size*64))
   g1=$crs_path/bn254_g1.dat
   g2=$crs_path/bn254_g2.dat
-  if [ ! -f "$g1" ] || [ $(stat -c%s "$g1") -lt $crs_size_bytes ]; then
+  # stat -c%s is Linux-only, use stat -f%z on macOS
+  local g1_size=0
+  if [ -f "$g1" ]; then
+    if [[ "$(uname)" == "Darwin" ]]; then
+      g1_size=$(stat -f%z "$g1")
+    else
+      g1_size=$(stat -c%s "$g1")
+    fi
+  fi
+  if [ ! -f "$g1" ] || [ $g1_size -lt $crs_size_bytes ]; then
     echo "Downloading crs of size: ${crs_size} ($((crs_size_bytes/(1024*1024)))MB)"
     mkdir -p $crs_path
     curl -s -H "Range: bytes=0-$((crs_size_bytes-1))" -o $g1 \
@@ -28,7 +37,15 @@ function build {
   crs_size=$((2**18))
   crs_size_bytes=$((crs_size*64))
   gg1=$crs_path/grumpkin_g1.flat.dat
-  if [ ! -f "$gg1" ] || [ $(stat -c%s "$gg1") -lt $crs_size_bytes ]; then
+  local gg1_size=0
+  if [ -f "$gg1" ]; then
+    if [[ "$(uname)" == "Darwin" ]]; then
+      gg1_size=$(stat -f%z "$gg1")
+    else
+      gg1_size=$(stat -c%s "$gg1")
+    fi
+  fi
+  if [ ! -f "$gg1" ] || [ $gg1_size -lt $crs_size_bytes ]; then
     echo "Downloading grumpkin crs of size: ${crs_size} ($((crs_size_bytes/(1024*1024)))MB)"
     curl -s -H "Range: bytes=0-$((crs_size_bytes-1))" -o $gg1 \
       https://crs.aztec.network/grumpkin_g1.dat
diff --git a/ci3/arch b/ci3/arch
index b4bf030fc5c6..ac2d92d00f18 100755
--- a/ci3/arch
+++ b/ci3/arch
@@ -1,7 +1,7 @@
 #!/usr/bin/env bash
 # Returns the standard artifact prefixes for each arch.
 case $(uname -m) in
-  aarch64)
+  aarch64|arm64)
     echo arm64
     ;;
   amd64|x86_64)
diff --git a/ci3/denoise b/ci3/denoise
index 5f9fa75ab8d7..0138114ffd90 100755
--- a/ci3/denoise
+++ b/ci3/denoise
@@ -77,7 +77,13 @@ function publish_log_final {
 
 function live_publish_log {
   while [ -f $outfile ]; do
-    if [ $(( $(date +%s) - $(stat -c %Y "$outfile") )) -le 5 ]; then
+    local file_mtime
+    if [[ "$(uname)" == "Darwin" ]]; then
+      file_mtime=$(stat -f %m "$outfile")
+    else
+      file_mtime=$(stat -c %Y "$outfile")
+    fi
+    if [ $(( $(date +%s) - $file_mtime )) -le 5 ]; then
       publish_log
     fi
     sleep 5
@@ -94,7 +100,13 @@ fi
 set +e
 echo -e "Executing: $cmd ${log_info:-}"
 echo -n "   0 "
-tail --sleep-interval=0.2 -n +1 -f "$outfile" > >(
+# macOS tail doesn't support --sleep-interval
+if [[ "$(uname)" == "Darwin" ]]; then
+  tail_args="-n +1 -f"
+else
+  tail_args="--sleep-interval=0.2 -n +1 -f"
+fi
+tail $tail_args "$outfile" > >(
   while IFS= read -r line; do
     dot_count=$((dot_count+1))
     [ $realtime -eq 1 ] && printf "."
diff --git a/ci3/source b/ci3/source
index c53bb28b3828..455c37625e55 100644
--- a/ci3/source
+++ b/ci3/source
@@ -3,7 +3,10 @@
 # This can be sourced multiple by scripts calling scripts, so it makes sense to only do certain sets through first pass.
 
 # Enter our script directory, allowing usage of scripts from any directory.
-[ -z "${NO_CD:-}" ] && cd "$(dirname $0)"
+# Skip cd if $0 is a shell binary (e.g., /bin/bash or /opt/homebrew/bin/bash)
+if [ -z "${NO_CD:-}" ] && [[ "$0" != */bash ]] && [[ "$0" != */zsh ]] && [[ "$0" != */sh ]]; then
+  cd "$(dirname $0)"
+fi
 
 # We export so we can use from exported functions.
 export root=${root:-$(git rev-parse --show-toplevel)}
@@ -21,6 +24,12 @@ fi
 # We are fine using foundry nightly.
 export FOUNDRY_DISABLE_NIGHTLY_WARNING=1
 
+# Fix for parallel setting XDG_CACHE_HOME to empty string, which breaks corepack.
+# If XDG_CACHE_HOME is set but empty, unset it to use the default.
+if [ -n "${XDG_CACHE_HOME+x}" ] && [ -z "$XDG_CACHE_HOME" ]; then
+  unset XDG_CACHE_HOME
+fi
+
 source $ci3/source_options
 source $ci3/source_stdlib
 source $ci3/source_color
diff --git a/ci3/source_stdlib b/ci3/source_stdlib
index 18ac41dc369d..4e4279f1329b 100644
--- a/ci3/source_stdlib
+++ b/ci3/source_stdlib
@@ -33,6 +33,8 @@ function get_num_cpus {
     else
       echo $((cpu_quota / cpu_period))
     fi
+  elif [[ "$(uname)" == "Darwin" ]]; then
+    sysctl -n hw.ncpu
   else
     nproc
   fi