diff --git a/eng/native/configurecompiler.cmake b/eng/native/configurecompiler.cmake
index 8f3d6ad671d476..6b9ac068fd87c6 100644
--- a/eng/native/configurecompiler.cmake
+++ b/eng/native/configurecompiler.cmake
@@ -20,6 +20,21 @@ include(CheckLinkerFlag)
 # "configureoptimization.cmake" must be included after CLR_CMAKE_HOST_UNIX has been set.
 include(${CMAKE_CURRENT_LIST_DIR}/configureoptimization.cmake)
 
+# Validate tryrun cache version matches current Emscripten version (browser-wasm only)
+if(CLR_CMAKE_TARGET_BROWSER AND DEFINED TRYRUN_BROWSER_EMSCRIPTEN_VERSION)
+    file(READ "${CMAKE_CURRENT_LIST_DIR}/../../src/mono/browser/emscripten-version.txt" CURRENT_EMSCRIPTEN_VERSION)
+    string(STRIP "${CURRENT_EMSCRIPTEN_VERSION}" CURRENT_EMSCRIPTEN_VERSION)
+    
+    if(NOT TRYRUN_BROWSER_EMSCRIPTEN_VERSION STREQUAL CURRENT_EMSCRIPTEN_VERSION)
+        message(WARNING 
+            "Emscripten version mismatch detected!\n"
+            "  Current Emscripten: ${CURRENT_EMSCRIPTEN_VERSION}\n"
+            "  Cached features for: ${TRYRUN_BROWSER_EMSCRIPTEN_VERSION}\n"
+            "  The CMake feature cache (eng/native/tryrun.browser.cmake) may be outdated.\n"
+            "  Consider regenerating the cache - see instructions in eng/native/tryrun.browser.cmake")
+    endif()
+endif()
+
 #-----------------------------------------------------
 # Initialize Cmake compiler flags and other variables
 #-----------------------------------------------------
diff --git a/eng/native/gen-buildsys.sh b/eng/native/gen-buildsys.sh
index 1d52c232b84572..186a179f78c0f2 100755
--- a/eng/native/gen-buildsys.sh
+++ b/eng/native/gen-buildsys.sh
@@ -107,6 +107,9 @@ if [[ "$host_arch" == "wasm" ]]; then
         fi
         export EMSDK_QUIET=1 && source "$EMSDK_PATH"/emsdk_env.sh
         cmake_command="emcmake $cmake_command"
+        # Use WASM-specific tryrun cache to speed up CMake configure
+        # The -C flag must be early in the command line to be effective
+        cmake_extra_defines="-C $scriptroot/tryrun.browser.cmake $cmake_extra_defines"
     elif [[ "$target_os" == "wasi" ]]; then
         if [[ -z "$WASI_SDK_PATH" ]]; then
             if [[ -d "$reporoot"/artifacts/wasi-sdk ]]; then
diff --git a/eng/native/tryrun.browser.cmake b/eng/native/tryrun.browser.cmake
new file mode 100644
index 00000000000000..87425dc4d7eee7
--- /dev/null
+++ b/eng/native/tryrun.browser.cmake
@@ -0,0 +1,393 @@
+# CMake pre-configured cache for WebAssembly (browser-wasm) cross-compilation
+#
+# This file caches the results of CMake feature detection checks and TRY_RUN tests
+# to significantly speed up the CMake configure phase for WebAssembly builds.
+#
+# IMPORTANT: This file is specific to the Emscripten version and WebAssembly target.
+# 
+# Valid for:
+#   - Emscripten version: 3.1.56
+#   - Target: wasm32-unknown-emscripten (browser-wasm)
+#   - Architecture: wasm32
+#   - OS: browser/Emscripten
+#
+# PERFORMANCE IMPACT:
+#   - Reduces CMake configure checks from 103 to 14 (86% reduction)
+#   - Configure phase: ~2-3 minutes → ~10-20 seconds
+#   - Eliminates: TRY_RUN tests, header checks, function checks, compiler tests
+#   - Accelerates both main CoreCLR build and sub-projects (zlib-ng, zstd)
+#
+# HOW TO USE:
+#   Automatically applied when building for browser-wasm. No special flags needed:
+#     ./build.sh -subset clr.runtime -os browser -arch wasm -c Debug
+#
+# VERSION TRACKING:
+#   The TRYRUN_BROWSER_EMSCRIPTEN_VERSION variable at the top of this file tracks
+#   which Emscripten version this cache was generated for. The build system
+#   validates this against src/mono/browser/emscripten-version.txt and warns
+#   if there's a mismatch.
+#
+# WHEN TO REGENERATE:
+#   This file should be regenerated when:
+#   - Emscripten version changes (see src/mono/browser/emscripten-version.txt)
+#   - New CMake feature checks are added to the CoreCLR build system
+#   - WebAssembly platform capabilities change significantly
+#
+# HOW TO REGENERATE:
+#   1. Temporarily disable this cache file:
+#        mv eng/native/tryrun.browser.cmake eng/native/tryrun.browser.cmake.bak
+#
+#   2. Clean and run a fresh configure:
+#        git clean -xdf artifacts/obj/coreclr/browser.wasm.Debug
+#        ./build.sh -subset clr.runtime -os browser -arch wasm -c Debug
+#        (Let it run until CMake configure completes, can stop after that)
+#
+#   3. Extract all feature check results:
+#        grep -E "^(HAVE_|HAS_|ONE_|PTHREAD_|REALPATH_|SEM_|COMPILER_)" \
+#          artifacts/obj/coreclr/browser.wasm.Debug/CMakeCache.txt | sort
+#
+#   4. Generate new cache entries (example script):
+#        while IFS= read -r line; do
+#          var=$(echo "$line" | cut -d: -f1)
+#          rest=$(echo "$line" | cut -d: -f2-)
+#          type=$(echo "$rest" | cut -d= -f1)
+#          value=$(echo "$rest" | cut -d= -f2-)
+#          [ -z "$value" ] && value='""'
+#          cache_type="INTERNAL"
+#          [ "$type" = "BOOL" ] && cache_type="BOOL"
+#          if [[ "$var" == *"_EXITCODE" ]]; then
+#            echo "set_cache_value($var $value)"
+#          else
+#            echo "set($var $value CACHE $cache_type \"\")"
+#          fi
+#        done < <(grep -E "^(HAVE_|HAS_|...)" CMakeCache.txt)
+#
+#   5. Update this file with:
+#        - New TRYRUN_BROWSER_EMSCRIPTEN_VERSION at the top of the file
+#        - New Emscripten version in header comment (line 9)
+#        - New cache entries (replacing old ones)
+#        - Verify no duplicate entries
+#
+#   6. Also update sub-project caches in:
+#        - src/native/external/zlib-ng.cmake (CLR_CMAKE_TARGET_BROWSER section)
+#        - src/native/external/zstd.cmake (CLR_CMAKE_TARGET_BROWSER section)
+#
+#   7. Test the regenerated cache:
+#        git clean -xdf artifacts/obj/coreclr/browser.wasm.Debug
+#        ./build.sh -subset clr.runtime -os browser -arch wasm -c Debug
+#        (Verify it loads and check count is minimal)
+#
+#   8. Restore if needed:
+#        mv eng/native/tryrun.browser.cmake.bak eng/native/tryrun.browser.cmake
+
+# Version tracking: This cache is valid for the following Emscripten version
+set(TRYRUN_BROWSER_EMSCRIPTEN_VERSION "3.1.56" CACHE INTERNAL "Emscripten version this cache was generated for")
+
+# Macro to set cache values (same as eng/native/tryrun.cmake)
+macro(set_cache_value)
+  set(${ARGV0} ${ARGV1} CACHE STRING "Result from TRY_RUN" FORCE)
+  set(${ARGV0}__TRYRUN_OUTPUT "dummy output" CACHE STRING "Output from TRY_RUN" FORCE)
+endmacro()
+
+# NOTE: This file is only used for WebAssembly/Emscripten builds.
+# No conditional check needed - the file is explicitly loaded via -C flag
+# only for browser-wasm builds in eng/native/gen-buildsys.sh
+
+# ============================================================================
+# TRY_RUN Exit Codes
+# ============================================================================
+
+set(COMPILER_SUPPORTS_F_ALIGNED_NEW 1 CACHE INTERNAL "")
+set(COMPILER_SUPPORTS_W_IMPLICIT_FALLTHROUGH 1 CACHE INTERNAL "")
+set(COMPILER_SUPPORTS_W_PRE_C11_COMPAT 1 CACHE INTERNAL "")
+set(COMPILER_SUPPORTS_W_RESERVED_IDENTIFIER 1 CACHE INTERNAL "")
+set(HAS_POSIX_SEMAPHORES_COMPILED TRUE CACHE INTERNAL "")
+set_cache_value(HAS_POSIX_SEMAPHORES_EXITCODE 0)
+set(HAS_POSIX_SEMAPHORES 1 CACHE INTERNAL "")
+set(HAS_PTHREAD_MUTEXES 1 CACHE INTERNAL "")
+set(HAS_SYSV_SEMAPHORES "" CACHE INTERNAL "")
+set(HAVE___GREGSET_T "" CACHE INTERNAL "")
+set(HAVE__LWP_SELF "" CACHE INTERNAL "")
+set(HAVE__SC_AVPHYS_PAGES 1 CACHE INTERNAL "")
+set(HAVE__SC_PHYS_PAGES 1 CACHE INTERNAL "")
+set(HAVE_ACCEPT4 1 CACHE INTERNAL "")
+set(HAVE_ALIGNED_ALLOC FALSE CACHE BOOL "")
+set(HAVE_ARC4RANDOM_BUF "" CACHE INTERNAL "")
+set(HAVE_ARM_ACLE_H "" CACHE INTERNAL "")
+set(HAVE_ATTRIBUTE_ALIGNED 1 CACHE INTERNAL "")
+set(HAVE_ATTRIBUTE_VISIBILITY_HIDDEN 1 CACHE INTERNAL "")
+set(HAVE_ATTRIBUTE_VISIBILITY_INTERNAL 1 CACHE INTERNAL "")
+set(HAVE_AUXV_HWCAP_H "" CACHE INTERNAL "")
+set(HAVE_BCRYPT_H "" CACHE INTERNAL "")
+set(HAVE_BROKEN_FIFO_KEVENT_COMPILED FALSE CACHE INTERNAL "")
+set(HAVE_BROKEN_FIFO_KEVENT "" CACHE INTERNAL "")
+set(HAVE_BROKEN_FIFO_SELECT_COMPILED FALSE CACHE INTERNAL "")
+set(HAVE_BROKEN_FIFO_SELECT "" CACHE INTERNAL "")
+set(HAVE_BSD_REGS_T FALSE CACHE INTERNAL "")
+set(HAVE_BUILTIN_ASSUME_ALIGNED 1 CACHE INTERNAL "")
+set(HAVE_BUILTIN_CTZ 1 CACHE INTERNAL "")
+set(HAVE_BUILTIN_CTZLL 1 CACHE INTERNAL "")
+set(HAVE_BUILTIN_MUL_OVERFLOW 1 CACHE INTERNAL "")
+set(HAVE_CFMAKERAW 1 CACHE INTERNAL "")
+set(HAVE_CFSETSPEED 1 CACHE INTERNAL "")
+set(HAVE_CHMOD 1 CACHE INTERNAL "")
+set(HAVE_CLOCK_GETTIME_NSEC_NP "" CACHE INTERNAL "")
+set(HAVE_CLOCK_MONOTONIC_COARSE 1 CACHE INTERNAL "")
+set(HAVE_CLOCK_MONOTONIC_COMPILED TRUE CACHE INTERNAL "")
+set_cache_value(HAVE_CLOCK_MONOTONIC_EXITCODE 0)
+set(HAVE_CLOCK_MONOTONIC 1 CACHE INTERNAL "")
+set(HAVE_CLOCK_THREAD_CPUTIME_COMPILED TRUE CACHE INTERNAL "")
+set_cache_value(HAVE_CLOCK_THREAD_CPUTIME_EXITCODE 255)
+set(HAVE_CLOCK_THREAD_CPUTIME "" CACHE INTERNAL "")
+set(HAVE_CONNECTX "" CACHE INTERNAL "")
+set(HAVE_CPUSET_T "" CACHE INTERNAL "")
+set(HAVE_CRT_EXTERNS_H "" CACHE INTERNAL "")
+set(HAVE_DIRECTIO "" CACHE INTERNAL "")
+set(HAVE_DIRENT_D_TYPE 1 CACHE INTERNAL "")
+set(HAVE_DIRENT_NAME_LEN "" CACHE INTERNAL "")
+set(HAVE_DISCONNECTX "" CACHE INTERNAL "")
+set(HAVE_DLFCN_H 1 CACHE INTERNAL "")
+set(HAVE_EPOLL "" CACHE INTERNAL "")
+set(HAVE_ERRNO_H 1 CACHE INTERNAL "")
+set(HAVE_ETHTOOL_H "" CACHE INTERNAL "")
+set(HAVE_F_DUPFD_CLOEXEC 1 CACHE INTERNAL "")
+set(HAVE_F_DUPFD 1 CACHE INTERNAL "")
+set(HAVE_F_FULLFSYNC "" CACHE INTERNAL "")
+set(HAVE_FALLOCATE "" CACHE INTERNAL "")
+set(HAVE_FCHMOD 1 CACHE INTERNAL "")
+set(HAVE_FCOPYFILE "" CACHE INTERNAL "")
+set(HAVE_FLOCK64 "" CACHE INTERNAL "")
+set(HAVE_FORK 1 CACHE INTERNAL "")
+set(HAVE_FPREGS_WITH_CW "" CACHE INTERNAL "")
+set(HAVE_FPSTATE_GLIBC_RESERVED1 "" CACHE INTERNAL "")
+set(HAVE_FSEEKO 1 CACHE INTERNAL "")
+set(HAVE_FSYNC 1 CACHE INTERNAL "")
+set(HAVE_FTRUNCATE64 "" CACHE INTERNAL "")
+set(HAVE_FUTIMENS 1 CACHE INTERNAL "")
+set(HAVE_FUTIMES "" CACHE INTERNAL "")
+set(HAVE_GET_PROC_INFO_IN_RANGE "" CACHE INTERNAL "")
+set(HAVE_GETAUXVAL "" CACHE INTERNAL "")
+set(HAVE_GETDOMAINNAME_SIZET 1 CACHE INTERNAL "")
+set(HAVE_GETDOMAINNAME 1 CACHE INTERNAL "")
+set(HAVE_GETGRGID_R 1 CACHE INTERNAL "")
+set(HAVE_GETGROUPLIST "" CACHE INTERNAL "")
+set(HAVE_GETHOSTNAME 1 CACHE INTERNAL "")
+set(HAVE_GETIFADDRS 1 CACHE INTERNAL "")
+set(HAVE_GETNAMEINFO_SIGNED_FLAGS 1 CACHE INTERNAL "")
+set(HAVE_GETNAMEINFO 1 CACHE INTERNAL "")
+set(HAVE_GETPEEREID "" CACHE INTERNAL "")
+set(HAVE_GETRLIMIT 1 CACHE INTERNAL "")
+set(HAVE_GMTIME_R 1 CACHE INTERNAL "")
+set(HAVE_GNU_LIBNAMES_H "" CACHE INTERNAL "")
+set(HAVE_GNU_STRERROR_R "" CACHE INTERNAL "")
+set(HAVE_GREGSET_T 1 CACHE INTERNAL "")
+set(HAVE_GSS_SPNEGO_MECHANISM "" CACHE INTERNAL "")
+set(HAVE_GSSFW_HEADERS "" CACHE INTERNAL "")
+set(HAVE_HAVE_IF_MSGHDR2 FALSE CACHE INTERNAL "")
+set(HAVE_HAVE_RT_MSGHDR FALSE CACHE INTERNAL "")
+set(HAVE_HAVE_RT_MSGHDR2 FALSE CACHE INTERNAL "")
+set(HAVE_HWPROBE_H "" CACHE INTERNAL "")
+set(HAVE_IF_MSGHDR2 "" CACHE INTERNAL "")
+set(HAVE_IN_EXCL_UNLINK "" CACHE INTERNAL "")
+set(HAVE_IN_PKTINFO 1 CACHE INTERNAL "")
+set(HAVE_INFTIM "" CACHE INTERNAL "")
+set(HAVE_INOTIFY_ADD_WATCH "" CACHE INTERNAL "")
+set(HAVE_INOTIFY_INIT "" CACHE INTERNAL "")
+set(HAVE_INOTIFY_RM_WATCH "" CACHE INTERNAL "")
+set(HAVE_IOCTL_WITH_INT_REQUEST 1 CACHE INTERNAL "")
+set(HAVE_IOCTL 1 CACHE INTERNAL "")
+set(HAVE_IOSS_H "" CACHE INTERNAL "")
+set(HAVE_IP_MREQN 1 CACHE INTERNAL "")
+set(HAVE_IP_MULTICAST_IFINDEX "" CACHE INTERNAL "")
+set(HAVE_KQUEUE "" CACHE INTERNAL "")
+set(HAVE_LCHFLAGS "" CACHE INTERNAL "")
+set(HAVE_LIBPTHREAD 1 CACHE INTERNAL "")
+set(HAVE_LINUX_AUXVEC_H "" CACHE INTERNAL "")
+set(HAVE_LINUX_CAN_H "" CACHE INTERNAL "")
+set(HAVE_LINUX_ERRQUEUE_H "" CACHE INTERNAL "")
+set(HAVE_LINUX_IN_H "" CACHE INTERNAL "")
+set(HAVE_LINUX_RTNETLINK_H "" CACHE INTERNAL "")
+set(HAVE_LINUX_USER_EVENTS_H "" CACHE INTERNAL "")
+set(HAVE_LSEEK64 "" CACHE INTERNAL "")
+set(HAVE_LTTNG_TRACEPOINT_H "" CACHE INTERNAL "")
+set(HAVE_LUTIMES "" CACHE INTERNAL "")
+set(HAVE_LWP_H "" CACHE INTERNAL "")
+set(HAVE_MACH_EXCEPTIONS "" CACHE INTERNAL "")
+set(HAVE_MACH_THREADS "" CACHE INTERNAL "")
+set(HAVE_MACH_VM_PARAM_H "" CACHE INTERNAL "")
+set(HAVE_MACH_VM_TYPES_H "" CACHE INTERNAL "")
+set(HAVE_MACHINE_NPX_H "" CACHE INTERNAL "")
+set(HAVE_MACHINE_REG_H "" CACHE INTERNAL "")
+set(HAVE_MACHINE_VMPARAM_H "" CACHE INTERNAL "")
+set(HAVE_MAKEDEV_FILEH "" CACHE INTERNAL "")
+set(HAVE_MAKEDEV_SYSMACROSH 1 CACHE INTERNAL "")
+set(HAVE_MALLOC_SIZE "" CACHE INTERNAL "")
+set(HAVE_MALLOC_USABLE_SIZE_NP "" CACHE INTERNAL "")
+set(HAVE_MALLOC_USABLE_SIZE 1 CACHE INTERNAL "")
+set(HAVE_MAP_HUGETLB 1 CACHE INTERNAL "")
+set(HAVE_MKSTEMP 1 CACHE INTERNAL "")
+set(HAVE_MKSTEMPS 1 CACHE INTERNAL "")
+set(HAVE_MMAP64 "" CACHE INTERNAL "")
+set(HAVE_MNTENT_H 1 CACHE INTERNAL "")
+set(HAVE_MNTINFO "" CACHE INTERNAL "")
+set(HAVE_NET_IF_ARP_H 1 CACHE INTERNAL "")
+set(HAVE_NET_IF_H 1 CACHE INTERNAL "")
+set(HAVE_NET_IFMEDIA_H "" CACHE INTERNAL "")
+set(HAVE_NETINET_ICMP_VAR_H "" CACHE INTERNAL "")
+set(HAVE_NETINET_IP_VAR_H "" CACHE INTERNAL "")
+set(HAVE_NETINET_TCP_VAR_H "" CACHE INTERNAL "")
+set(HAVE_NETINET_UDP_VAR_H "" CACHE INTERNAL "")
+set(HAVE_NETPACKET_PACKET_H 1 CACHE INTERNAL "")
+set(HAVE_NO_INTERPOSITION 1 CACHE INTERNAL "")
+set(HAVE_NON_LEGACY_STATFS 1 CACHE INTERNAL "")
+set(HAVE_O_CLOEXEC 1 CACHE INTERNAL "")
+set(HAVE_OFF64_T TRUE CACHE INTERNAL "")
+set(HAVE_PIPE 1 CACHE INTERNAL "")
+set(HAVE_PIPE2 1 CACHE INTERNAL "")
+set(HAVE_POLL 1 CACHE INTERNAL "")
+set(HAVE_POSIX_ADVISE 1 CACHE INTERNAL "")
+set(HAVE_POSIX_FADVISE64 "" CACHE INTERNAL "")
+set(HAVE_POSIX_MADVISE 1 CACHE INTERNAL "")
+set(HAVE_POSIX_MEMALIGN 1 CACHE INTERNAL "")
+set(HAVE_PR_SET_PTRACER "" CACHE INTERNAL "")
+set(HAVE_PRCTL_H "" CACHE INTERNAL "")
+set(HAVE_PREADV 1 CACHE INTERNAL "")
+set(HAVE_PROCFS_CTL_COMPILED TRUE CACHE INTERNAL "")
+set_cache_value(HAVE_PROCFS_CTL_EXITCODE 1)
+set(HAVE_PROCFS_CTL "" CACHE INTERNAL "")
+set(HAVE_PROCFS_H "" CACHE INTERNAL "")
+set(HAVE_PROCFS_STAT_COMPILED TRUE CACHE INTERNAL "")
+set_cache_value(HAVE_PROCFS_STAT_EXITCODE 1)
+set(HAVE_PROCFS_STAT "" CACHE INTERNAL "")
+set(HAVE_PROCFS_STATM_COMPILED TRUE CACHE INTERNAL "")
+set_cache_value(HAVE_PROCFS_STATM_EXITCODE 1)
+set(HAVE_PROCFS_STATM "" CACHE INTERNAL "")
+set(HAVE_PRWATCH_T FALSE CACHE INTERNAL "")
+set(HAVE_PT_REGS FALSE CACHE INTERNAL "")
+set(HAVE_PTHREAD_ATTR_GET_NP "" CACHE INTERNAL "")
+set(HAVE_PTHREAD_CONDATTR_SETCLOCK 1 CACHE INTERNAL "")
+set(HAVE_PTHREAD_GETAFFINITY_NP "" CACHE INTERNAL "")
+set(HAVE_PTHREAD_GETATTR_NP 1 CACHE INTERNAL "")
+set(HAVE_PTHREAD_GETCPUCLOCKID 1 CACHE INTERNAL "")
+set(HAVE_PTHREAD_GETTHREADID_NP "" CACHE INTERNAL "")
+set(HAVE_PTHREAD_H 1 CACHE INTERNAL "")
+set(HAVE_PTHREAD_IN_LIBC 1 CACHE INTERNAL "")
+set(HAVE_PTHREAD_MUTEX_CLOCKLOCK "" CACHE INTERNAL "")
+set(HAVE_PTHREAD_NP_H "" CACHE INTERNAL "")
+set(HAVE_PTHREAD_RWLOCK_T TRUE CACHE INTERNAL "")
+set(HAVE_PTHREAD_SETAFFINITY_NP "" CACHE INTERNAL "")
+set(HAVE_PTHREAD_SETCANCELSTATE 1 CACHE INTERNAL "")
+set(HAVE_PTHREAD_THREADID_NP "" CACHE INTERNAL "")
+set(HAVE_PTRDIFF_T 1 CACHE INTERNAL "")
+set(HAVE_PUBLIC_XSTATE_STRUCT "" CACHE INTERNAL "")
+set(HAVE_PWRITEV 1 CACHE INTERNAL "")
+set(HAVE_RESOURCE_H 1 CACHE INTERNAL "")
+set(HAVE_RT_MSGHDR "" CACHE INTERNAL "")
+set(HAVE_RT_MSGHDR2 "" CACHE INTERNAL "")
+set(HAVE_RUNETYPE_H "" CACHE INTERNAL "")
+set(HAVE_SCHED_GET_PRIORITY_COMPILED FALSE CACHE INTERNAL "")
+set(HAVE_SCHED_GET_PRIORITY "" CACHE INTERNAL "")
+set(HAVE_SCHED_GETAFFINITY "" CACHE INTERNAL "")
+set(HAVE_SCHED_GETCPU "" CACHE INTERNAL "")
+set(HAVE_SCHED_SETAFFINITY "" CACHE INTERNAL "")
+set(HAVE_SEMAPHORE_H 1 CACHE INTERNAL "")
+set(HAVE_SENDFILE_4 "" CACHE INTERNAL "")
+set(HAVE_SENDFILE_6 "" CACHE INTERNAL "")
+set(HAVE_SENDFILE_7 "" CACHE INTERNAL "")
+set(HAVE_SETRLIMIT 1 CACHE INTERNAL "")
+set(HAVE_SIGALTSTACK 1 CACHE INTERNAL "")
+set(HAVE_SIZEOF_OFF_T TRUE CACHE INTERNAL "")
+set(HAVE_SOCKADDR_UN_SUN_PATH 1 CACHE INTERNAL "")
+set(HAVE_STAT_BIRTHTIME "" CACHE INTERNAL "")
+set(HAVE_STAT_FLAGS "" CACHE INTERNAL "")
+set(HAVE_STAT_NSEC "" CACHE INTERNAL "")
+set(HAVE_STAT_TIM 1 CACHE INTERNAL "")
+set(HAVE_STAT_TIMESPEC "" CACHE INTERNAL "")
+set(HAVE_STAT64 "" CACHE INTERNAL "")
+set(HAVE_STATFS_FSTYPENAME "" CACHE INTERNAL "")
+set(HAVE_STATFS_MOUNT "" CACHE INTERNAL "")
+set(HAVE_STATFS_SIZE TRUE CACHE INTERNAL "")
+set(HAVE_STATFS_VFS 1 CACHE INTERNAL "")
+set(HAVE_STATFS 1 CACHE INTERNAL "")
+set(HAVE_STATVFS_BASETYPE "" CACHE INTERNAL "")
+set(HAVE_STATVFS_FSTYPENAME "" CACHE INTERNAL "")
+set(HAVE_STATVFS 1 CACHE INTERNAL "")
+set(HAVE_STDDEF_H 1 CACHE INTERNAL "")
+set(HAVE_STDINT_H 1 CACHE INTERNAL "")
+set(HAVE_STRCPY_S "" CACHE INTERNAL "")
+set(HAVE_STRERROR 1 CACHE INTERNAL "")
+set(HAVE_STRERRORNAME_NP "" CACHE INTERNAL "")
+set(HAVE_STRLCAT 1 CACHE INTERNAL "")
+set(HAVE_SWAPCTL "" CACHE INTERNAL "")
+set(HAVE_SYS_AUXV_H "" CACHE INTERNAL "")
+set(HAVE_SYS_CDEFS_H "" CACHE INTERNAL "")
+set(HAVE_SYS_FILIO_H "" CACHE INTERNAL "")
+set(HAVE_SYS_INOTIFY_H "" CACHE INTERNAL "")
+set(HAVE_SYS_IOCTL_H 1 CACHE INTERNAL "")
+set(HAVE_SYS_LWP_H "" CACHE INTERNAL "")
+set(HAVE_SYS_MEMBARRIER_H 1 CACHE INTERNAL "")
+set(HAVE_SYS_MMAN_H 1 CACHE INTERNAL "")
+set(HAVE_SYS_MNTENT_H "" CACHE INTERNAL "")
+set(HAVE_SYS_MOUNT_H 1 CACHE INTERNAL "")
+set(HAVE_SYS_POLL_H "" CACHE INTERNAL "")
+set(HAVE_SYS_PROCINFO_H "" CACHE INTERNAL "")
+set(HAVE_SYS_PTRACE_H "" CACHE INTERNAL "")
+set(HAVE_SYS_SDT_H "" CACHE INTERNAL "")
+set(HAVE_SYS_SOCKET_H 1 CACHE INTERNAL "")
+set(HAVE_SYS_SOCKIO_H "" CACHE INTERNAL "")
+set(HAVE_SYS_STATFS_H 1 CACHE INTERNAL "")
+set(HAVE_SYS_STATVFS_H 1 CACHE INTERNAL "")
+set(HAVE_SYS_SYSCTL_H "" CACHE INTERNAL "")
+set(HAVE_SYS_TIME_H 1 CACHE INTERNAL "")
+set(HAVE_SYS_TYPES_H 1 CACHE INTERNAL "")
+set(HAVE_SYS_UCONTEXT_H 1 CACHE INTERNAL "")
+set(HAVE_SYS_UIO_H 1 CACHE INTERNAL "")
+set(HAVE_SYS_VMPARAM_H "" CACHE INTERNAL "")
+set(HAVE_SYSCONF 1 CACHE INTERNAL "")
+set(HAVE_SYSCTL "" CACHE INTERNAL "")
+set(HAVE_SYSCTLBYNAME "" CACHE INTERNAL "")
+set(HAVE_SYSINFO_WITH_MEM_UNIT 1 CACHE INTERNAL "")
+set(HAVE_SYSINFO "" CACHE INTERNAL "")
+set(HAVE_SYSLOG_H 1 CACHE INTERNAL "")
+set(HAVE_TCP_FSM_H "" CACHE INTERNAL "")
+set(HAVE_TCP_H_TCP_KEEPALIVE "" CACHE INTERNAL "")
+set(HAVE_TCP_H_TCPSTATE_ENUM 1 CACHE INTERNAL "")
+set(HAVE_TERMIOS_H 1 CACHE INTERNAL "")
+set(HAVE_TERMIOS2 "" CACHE INTERNAL "")
+set(HAVE_THREAD_SELF "" CACHE INTERNAL "")
+set(HAVE_TIOCGWINSZ 1 CACHE INTERNAL "")
+set(HAVE_TTRACE "" CACHE INTERNAL "")
+set(HAVE_UCONTEXT_H 1 CACHE INTERNAL "")
+set(HAVE_UCONTEXT_T TRUE CACHE INTERNAL "")
+set(HAVE_UNISTD_H 1 CACHE INTERNAL "")
+set(HAVE_UNW_AARCH64_X19 1 CACHE INTERNAL "")
+set(HAVE_UNW_GET_ACCESSORS "" CACHE INTERNAL "")
+set(HAVE_UNW_GET_SAVE_LOC "" CACHE INTERNAL "")
+set(HAVE_UTIMENSAT 1 CACHE INTERNAL "")
+set(HAVE_UTSNAME_DOMAINNAME "" CACHE INTERNAL "")
+set(HAVE_VFORK 1 CACHE INTERNAL "")
+set(HAVE_VM_ALLOCATE "" CACHE INTERNAL "")
+set(HAVE_VM_FLAGS_SUPERPAGE_SIZE_ANY "" CACHE INTERNAL "")
+set(HAVE_VM_READ "" CACHE INTERNAL "")
+set(HAVE_WORKING_CLOCK_GETTIME_COMPILED TRUE CACHE INTERNAL "")
+set_cache_value(HAVE_WORKING_CLOCK_GETTIME_EXITCODE 0)
+set(HAVE_WORKING_CLOCK_GETTIME 1 CACHE INTERNAL "")
+set(HAVE_WORKING_GETTIMEOFDAY_COMPILED TRUE CACHE INTERNAL "")
+set_cache_value(HAVE_WORKING_GETTIMEOFDAY_EXITCODE 0)
+set(HAVE_WORKING_GETTIMEOFDAY 1 CACHE INTERNAL "")
+set(HAVE_XSW_USAGE "" CACHE INTERNAL "")
+set(HAVE_XSWDEV "" CACHE INTERNAL "")
+set(HAVE_YIELD_SYSCALL "" CACHE INTERNAL "")
+set(ONE_SHARED_MAPPING_PER_FILEREGION_PER_PROCESS_COMPILED TRUE CACHE INTERNAL "")
+set_cache_value(ONE_SHARED_MAPPING_PER_FILEREGION_PER_PROCESS_EXITCODE 1)
+set(ONE_SHARED_MAPPING_PER_FILEREGION_PER_PROCESS "" CACHE INTERNAL "")
+set(PTHREAD_CREATE_MODIFIES_ERRNO_COMPILED TRUE CACHE INTERNAL "")
+set_cache_value(PTHREAD_CREATE_MODIFIES_ERRNO_EXITCODE 1)
+set(PTHREAD_CREATE_MODIFIES_ERRNO "" CACHE INTERNAL "")
+set(PTHREAD_RWLOCK_T 32 CACHE INTERNAL "")
+set(REALPATH_SUPPORTS_NONEXISTENT_FILES_COMPILED TRUE CACHE INTERNAL "")
+set_cache_value(REALPATH_SUPPORTS_NONEXISTENT_FILES_EXITCODE 1)
+set(REALPATH_SUPPORTS_NONEXISTENT_FILES "" CACHE INTERNAL "")
+set(SEM_INIT_MODIFIES_ERRNO_COMPILED TRUE CACHE INTERNAL "")
+set_cache_value(SEM_INIT_MODIFIES_ERRNO_EXITCODE 1)
+set(SEM_INIT_MODIFIES_ERRNO "" CACHE INTERNAL "")
diff --git a/src/native/external/zlib-ng.cmake b/src/native/external/zlib-ng.cmake
index b146287c7dc323..aae68470378289 100644
--- a/src/native/external/zlib-ng.cmake
+++ b/src/native/external/zlib-ng.cmake
@@ -20,11 +20,39 @@ if(CLR_CMAKE_TARGET_ARCH_ARM AND CLR_CMAKE_TARGET_LINUX)
     set(WITH_NEON OFF)
 endif()
 
-if (CLR_CMAKE_TARGET_BROWSER OR CLR_CMAKE_TARGET_WASI)
+if (CLR_CMAKE_TARGET_WASI)
   # 'aligned_alloc' is not available in browser/wasi, yet it is set by zlib-ng/CMakeLists.txt.
   set(HAVE_ALIGNED_ALLOC FALSE CACHE BOOL "have aligned_alloc" FORCE)
 endif()
 
+if (CLR_CMAKE_TARGET_BROWSER)
+  # 'aligned_alloc' is not available in browser, yet it is set by zlib-ng/CMakeLists.txt.
+  set(HAVE_ALIGNED_ALLOC FALSE CACHE BOOL "have aligned_alloc" FORCE)
+  
+  # Pre-cache zlib-ng CMake checks to speed up configure for browser
+  # These values match the results for Emscripten/WASM target
+  set(HAVE_ARM_ACLE_H "" CACHE INTERNAL "")
+  set(HAVE_SYS_AUXV_H "" CACHE INTERNAL "")
+  set(HAVE_SYS_SDT_H "" CACHE INTERNAL "")
+  set(HAVE_UNISTD_H 1 CACHE INTERNAL "")
+  set(HAVE_LINUX_AUXVEC_H "" CACHE INTERNAL "")
+  set(HAVE_SYS_TYPES_H 1 CACHE INTERNAL "")
+  set(HAVE_STDINT_H 1 CACHE INTERNAL "")
+  set(HAVE_STDDEF_H 1 CACHE INTERNAL "")
+  set(HAVE_FSEEKO 1 CACHE INTERNAL "")
+  set(HAVE_STRERROR 1 CACHE INTERNAL "")
+  set(HAVE_POSIX_MEMALIGN 1 CACHE INTERNAL "")
+  set(HAVE_ATTRIBUTE_VISIBILITY_HIDDEN 1 CACHE INTERNAL "")
+  set(HAVE_ATTRIBUTE_VISIBILITY_INTERNAL 1 CACHE INTERNAL "")
+  set(HAVE_ATTRIBUTE_ALIGNED 1 CACHE INTERNAL "")
+  set(HAVE_BUILTIN_ASSUME_ALIGNED 1 CACHE INTERNAL "")
+  set(HAVE_BUILTIN_CTZ 1 CACHE INTERNAL "")
+  set(HAVE_BUILTIN_CTZLL 1 CACHE INTERNAL "")
+  set(HAVE_PTRDIFF_T 1 CACHE INTERNAL "")
+  set(HAVE_NO_INTERPOSITION 1 CACHE INTERNAL "")
+  set(FNO_LTO_AVAILABLE 1 CACHE INTERNAL "")
+endif()
+
 if (MSVC)
   #zlib-ng sets /utf-8 which clashes with /source-charset:utf-8 that we set centrally
   get_directory_property(dirCompileOptions COMPILE_OPTIONS)
diff --git a/src/native/external/zstd.cmake b/src/native/external/zstd.cmake
index a00fcea814275f..1d3b104ffe5974 100644
--- a/src/native/external/zstd.cmake
+++ b/src/native/external/zstd.cmake
@@ -17,6 +17,28 @@ set(ZSTD_BUILD_SHARED OFF)
 set(ZSTD_MULTITHREAD_SUPPORT OFF)
 set(ZSTD_LEGACY_SUPPORT OFF)
 
+# Pre-cache zstd CMake checks to speed up configure for browser
+if (CLR_CMAKE_TARGET_BROWSER)
+  set(C_FLAG_WALL 1 CACHE INTERNAL "")
+  set(CXX_FLAG_WALL 1 CACHE INTERNAL "")
+  set(C_FLAG_WEXTRA 1 CACHE INTERNAL "")
+  set(CXX_FLAG_WEXTRA 1 CACHE INTERNAL "")
+  set(C_FLAG_WUNDEF 1 CACHE INTERNAL "")
+  set(CXX_FLAG_WUNDEF 1 CACHE INTERNAL "")
+  set(C_FLAG_WSHADOW 1 CACHE INTERNAL "")
+  set(CXX_FLAG_WSHADOW 1 CACHE INTERNAL "")
+  set(C_FLAG_WCAST_ALIGN 1 CACHE INTERNAL "")
+  set(CXX_FLAG_WCAST_ALIGN 1 CACHE INTERNAL "")
+  set(C_FLAG_WCAST_QUAL 1 CACHE INTERNAL "")
+  set(CXX_FLAG_WCAST_QUAL 1 CACHE INTERNAL "")
+  set(C_FLAG_WSTRICT_PROTOTYPES 1 CACHE INTERNAL "")
+  set(LD_FLAG_WL_Z_NOEXECSTACK 1 CACHE INTERNAL "")
+  set(C_FLAG_QUNUSED_ARGUMENTS 1 CACHE INTERNAL "")
+  set(CXX_FLAG_QUNUSED_ARGUMENTS 1 CACHE INTERNAL "")
+  set(C_FLAG_WA_NOEXECSTACK 1 CACHE INTERNAL "")
+  set(CXX_FLAG_WA_NOEXECSTACK 1 CACHE INTERNAL "")
+endif()
+
 set(__CURRENT_BUILD_SHARED_LIBS ${BUILD_SHARED_LIBS})
 set(BUILD_SHARED_LIBS OFF)
 FetchContent_MakeAvailable(zstd)
diff --git a/src/native/libs/configure.cmake b/src/native/libs/configure.cmake
index 42821749e8f6f5..4a697287d3bd54 100644
--- a/src/native/libs/configure.cmake
+++ b/src/native/libs/configure.cmake
@@ -14,6 +14,10 @@ if (CLR_CMAKE_TARGET_APPLE)
     # This ensures an even playing field.
     include_directories(SYSTEM /usr/local/include)
     add_compile_options(-Wno-poison-system-directories)
+elseif (CMAKE_HOST_SYSTEM_NAME STREQUAL "Darwin" AND CLR_CMAKE_TARGET_BROWSER)
+    # When cross-compiling for browser-wasm on macOS, suppress warnings about
+    # /usr/local/include which may be added by the toolchain (e.g., brew's clang)
+    add_compile_options(-Wno-poison-system-directories)
 elseif (CLR_CMAKE_TARGET_FREEBSD)
     include_directories(SYSTEM ${CROSS_ROOTFS}/usr/local/include)
     set(CMAKE_REQUIRED_INCLUDES ${CROSS_ROOTFS}/usr/local/include)