diff --git a/.github/workflows/s2n-prelude-changes.yml b/.github/workflows/s2n-prelude-changes.yml
new file mode 100644
index 00000000..073e5bb1
--- /dev/null
+++ b/.github/workflows/s2n-prelude-changes.yml
@@ -0,0 +1,32 @@
+# Detect changes to s2n_prelude.h to update our `Package.swift` and stay in sync with it.
+# See: https://github.com/awslabs/aws-crt-swift/pull/299 for updating the Package.swift.
+
+name: s2n_prelude.h Change Detector
+
+on: [push]
+
+jobs:
+  check-for-changes:
+
+    runs-on: ubuntu-24.04 # latest
+
+    steps:
+    - name: Checkout Sources
+      uses: actions/checkout@v4
+      with:     
+        submodules: true 
+
+    - name: Check s2n_prelude.h
+      run: |
+        TMPFILE=$(mktemp)
+          echo "116f1525acbc94c91b0ee2ea2af9fdef aws-common-runtime/s2n/utils/s2n_prelude.h" > $TMPFILE
+        md5sum --check $TMPFILE
+
+    # No further steps if successful
+
+    - name: Echo fail
+      if: failure()
+      run: |
+          echo "The aws-crt-swift has a hack to manually define macros which are defined in s2n_prelude.h in Package.Swift.
+                This check will fail whenever s2n_prelude.h is updated by the S2N team. You should make sure that Package.Swift is updated accordingly
+                with the s2n_prelude.h changes and then run `md5sum aws-common-runtime/s2n/utils/s2n_prelude.h` and update the value above."
diff --git a/Package.swift b/Package.swift
index 1aac45ce..98535e61 100644
--- a/Package.swift
+++ b/Package.swift
@@ -100,8 +100,17 @@ packageTargets.append(.target(
     publicHeadersPath: "api",
     cSettings: [
         .headerSearchPath("./"),
-        .define("POSIX_C_SOURCE=200809L"),
-        .define("S2N_NO_PQ")
+        .define("S2N_NO_PQ"),
+        // This is a hack to get around the fact that S2N uses the compiler option `-include`
+        // to include `s2n_prelude.h` in all .c files. Since SwiftPM doesn't support compiler flags,
+        // we manually define the macros from `s2n_prelude.h`. When SwiftPM supports compiler flags
+        // or building packages using CMake, this hack should be removed.
+        // We are not defining `S2N_API` because we don't need to expose any symbols from S2N in crt-swift.
+        .define("_S2N_PRELUDE_INCLUDED"),
+        .define("S2N_BUILD_RELEASE"),
+        .define("_FORTIFY_SOURCE", to: "2"),
+        .define("POSIX_C_SOURCE", to: "200809L"),
+
     ]
 ))
 #endif
@@ -146,9 +155,6 @@ var awsCChecksumsExcludes = [
     "cmake",
     "tests"]
 
-// swift never uses Microsoft Visual C++ compiler
-awsCChecksumsExcludes.append("source/intel/visualc")
-
 // Hardware accelerated checksums are disabled because SwiftPM doesn't like the necessary compiler flags.
 // We can add it once SwiftPM has the necessary support for CPU flags or builds C libraries
 // using CMake.
diff --git a/aws-common-runtime/aws-c-auth b/aws-common-runtime/aws-c-auth
index 48d647bf..3982bd75 160000
--- a/aws-common-runtime/aws-c-auth
+++ b/aws-common-runtime/aws-c-auth
@@ -1 +1 @@
-Subproject commit 48d647bf43f8872e4dc5ec6343b0c5974195fbdd
+Subproject commit 3982bd75fea74efd8f9b462b27fedd4599db4f53
diff --git a/aws-common-runtime/aws-c-cal b/aws-common-runtime/aws-c-cal
index 2cb1d2ea..656762ae 160000
--- a/aws-common-runtime/aws-c-cal
+++ b/aws-common-runtime/aws-c-cal
@@ -1 +1 @@
-Subproject commit 2cb1d2eac925e2dbc45025eb89af82bd790c23a0
+Subproject commit 656762aefbee2bc8f509cb23cd107abff20a72bb
diff --git a/aws-common-runtime/aws-c-common b/aws-common-runtime/aws-c-common
index faa6c0f0..63187b97 160000
--- a/aws-common-runtime/aws-c-common
+++ b/aws-common-runtime/aws-c-common
@@ -1 +1 @@
-Subproject commit faa6c0f00802fc861e7252404f65fb1e0617ca8e
+Subproject commit 63187b976a482309e23296c5f967fc19c4131746
diff --git a/aws-common-runtime/aws-c-compression b/aws-common-runtime/aws-c-compression
index f36d0167..c6c1191e 160000
--- a/aws-common-runtime/aws-c-compression
+++ b/aws-common-runtime/aws-c-compression
@@ -1 +1 @@
-Subproject commit f36d01672d61e49d96a777870d456f66fa391cd4
+Subproject commit c6c1191e525e5aa6ead9e1afc392e35d3b50331e
diff --git a/aws-common-runtime/aws-c-event-stream b/aws-common-runtime/aws-c-event-stream
index 1b3825fc..d2dcc934 160000
--- a/aws-common-runtime/aws-c-event-stream
+++ b/aws-common-runtime/aws-c-event-stream
@@ -1 +1 @@
-Subproject commit 1b3825fc9cae2e9c7ed7479ee5d354d52ebdf7a0
+Subproject commit d2dcc9344dae24de320866045d85166d8a91a0d1
diff --git a/aws-common-runtime/aws-c-http b/aws-common-runtime/aws-c-http
index 6068653e..fc3eded2 160000
--- a/aws-common-runtime/aws-c-http
+++ b/aws-common-runtime/aws-c-http
@@ -1 +1 @@
-Subproject commit 6068653e1d582bd8e7d1c9f81f86beaf10444e3d
+Subproject commit fc3eded2465c37d07fd9cc15e9b5b011224c9c9a
diff --git a/aws-common-runtime/aws-c-io b/aws-common-runtime/aws-c-io
index e3637404..fcb38c80 160000
--- a/aws-common-runtime/aws-c-io
+++ b/aws-common-runtime/aws-c-io
@@ -1 +1 @@
-Subproject commit e36374047beadc72a0eb6df14ce3cbc822a789a3
+Subproject commit fcb38c804364dd627c335da752a99a125a88f6e9
diff --git a/aws-common-runtime/aws-c-sdkutils b/aws-common-runtime/aws-c-sdkutils
index 4658412a..ce09f797 160000
--- a/aws-common-runtime/aws-c-sdkutils
+++ b/aws-common-runtime/aws-c-sdkutils
@@ -1 +1 @@
-Subproject commit 4658412a61ad5749db92a8d1e0717cb5e76ada1c
+Subproject commit ce09f79768653dbdc810fc14cad8685dd90acba1
diff --git a/aws-common-runtime/aws-checksums b/aws-common-runtime/aws-checksums
index ce04ab00..3e4101b9 160000
--- a/aws-common-runtime/aws-checksums
+++ b/aws-common-runtime/aws-checksums
@@ -1 +1 @@
-Subproject commit ce04ab00b3ecc41912f478bfedca39f8e1919d6b
+Subproject commit 3e4101b9f85a2c090774d27ae2131fca1082f522
diff --git a/aws-common-runtime/config/aws/common/config.h b/aws-common-runtime/config/aws/common/config.h
index 7d00728c..df0e2d39 100644
--- a/aws-common-runtime/config/aws/common/config.h
+++ b/aws-common-runtime/config/aws/common/config.h
@@ -5,6 +5,7 @@
 
 #ifndef AWS_COMMON_CONFIG_H
 #define AWS_COMMON_CONFIG_H
+
 /*
  * This header exposes compiler feature test results determined during cmake
  * configure time to inline function implementations. The macros defined here
@@ -13,7 +14,7 @@
  */
 #ifdef __APPLE__
 /* This is a trick to skip OpenSSL header on Apple platforms since Swift Package Manager is not smart enough to exclude
- * some headers. 
+ * some headers.
  */
 #    define AWS_C_CAL_OPENSSLCRYPTO_COMMON_H
 #endif
diff --git a/aws-common-runtime/s2n b/aws-common-runtime/s2n
index ffe0bf42..493b7716 160000
--- a/aws-common-runtime/s2n
+++ b/aws-common-runtime/s2n
@@ -1 +1 @@
-Subproject commit ffe0bf42da8f139eff8fd2237f47fbde40b478fb
+Subproject commit 493b77167dc367c394de23cfe78a029298e2a254