diff --git a/.github/scripts/ci-btest.sh b/.github/scripts/ci-btest.sh
index 052a4ad..26fa345 100755
--- a/.github/scripts/ci-btest.sh
+++ b/.github/scripts/ci-btest.sh
@@ -7,4 +7,4 @@ export RUST_BACKTRACE=1
 cd $RUBY_BUILD_PATH
 
 echo "============ Bootstrape tests (btest) ($DEBUG_LEVEL) ============="
-make btest RUN_OPTS="--mmtk-plan=Immix" TESTOPTS="-v"
+make btest RUN_OPTS="--mmtk-plan=$CHOSEN_PLAN" TESTOPTS="-v"
diff --git a/.github/scripts/ci-test-all.sh b/.github/scripts/ci-test-all.sh
index 90a021a..f9978aa 100755
--- a/.github/scripts/ci-test-all.sh
+++ b/.github/scripts/ci-test-all.sh
@@ -13,7 +13,7 @@ case $DEBUG_LEVEL in
         ;;
     release)
         TEST_CASES=$(cat $BINDING_PATH/ruby-test-cases.txt | grep -v '#' | ruby -ne 'puts "../#{$_}"' | xargs)
-        make test-all TESTS="$TEST_CASES" RUN_OPTS="--mmtk-plan=Immix" TESTOPTS="-v"
+        make test-all TESTS="$TEST_CASES" RUN_OPTS="--mmtk-plan=$CHOSEN_PLAN" TESTOPTS="-v"
         ;;
     *)
         echo "Unexpected debug level: $DEBUG_LEVEL"
diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 9be2b15..82c03ef 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -17,7 +17,7 @@ jobs:
       fail-fast: true
     steps:
       - name: Checkout MMTk Ruby binding
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           path: ./git/mmtk-ruby
       - name: Setup environment
@@ -34,8 +34,10 @@ jobs:
       fail-fast: true
       matrix:
         debug-level: ["debug", "release"]
+        plan: ["MarkSweep", "Immix"]
     env:
       DEBUG_LEVEL: ${{ matrix.debug-level }}
+      CHOSEN_PLAN: ${{ matrix.plan }}
     steps:
       - name: Checkout MMTk Ruby binding
         uses: actions/checkout@v4
diff --git a/mmtk/Cargo.lock b/mmtk/Cargo.lock
index 206b8d0..daa074c 100644
--- a/mmtk/Cargo.lock
+++ b/mmtk/Cargo.lock
@@ -4,9 +4,9 @@ version = 3
 
 [[package]]
 name = "aho-corasick"
-version = "1.1.2"
+version = "1.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b2969dcb958b36655471fc61f7e416fa76033bdd4bfed0678d8fee1e2d07a1f0"
+checksum = "8e60d3430d3a69478ad0993f19238d2df97c507009a52b3c10addcd7f6bcb916"
 dependencies = [
  "memchr",
 ]
@@ -38,15 +38,15 @@ checksum = "41e67cd8309bbd06cd603a9e693a784ac2e5d1e955f11286e355089fcab3047c"
 
 [[package]]
 name = "autocfg"
-version = "1.1.0"
+version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"
+checksum = "f1fdabc7756949593fe60f30ec81974b613357de856987752631dea1e3394c80"
 
 [[package]]
 name = "bitflags"
-version = "2.4.2"
+version = "2.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ed570934406eb16438a4e976b1b4500774099c13b8cb96eec99f620f05090ddf"
+checksum = "cf4b9d6a944f767f8e5e0db018570623c85f3d925ac718db4e06d0187adb21c1"
 
 [[package]]
 name = "built"
@@ -74,7 +74,7 @@ checksum = "4da9a32f3fed317401fa3c862968128267c3106685286e15d5aaa3d7389c2f60"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.52",
+ "syn 2.0.55",
 ]
 
 [[package]]
@@ -195,7 +195,7 @@ checksum = "f282cfdfe92516eb26c2af8589c274c7c17681f5ecc03c18255fe741c6aa64eb"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.52",
+ "syn 2.0.55",
 ]
 
 [[package]]
@@ -222,9 +222,9 @@ dependencies = [
 
 [[package]]
 name = "git2"
-version = "0.18.2"
+version = "0.18.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1b3ba52851e73b46a4c3df1d89343741112003f0f6f13beb0dfac9e457c3fdcd"
+checksum = "232e6a7bfe35766bf715e55a88b39a700596c0ccfd88cd3680b4cdb40d66ef70"
 dependencies = [
  "bitflags",
  "libc",
@@ -316,9 +316,9 @@ dependencies = [
 
 [[package]]
 name = "libz-sys"
-version = "1.1.15"
+version = "1.1.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "037731f5d3aaa87a5675e895b63ddff1a87624bc29f77004ea829809654e48f6"
+checksum = "5e143b5e666b2695d28f6bca6497720813f699c9602dd7f5cac91008b8ada7f9"
 dependencies = [
  "cc",
  "libc",
@@ -344,15 +344,15 @@ checksum = "90ed8c1e510134f979dbc4f070f87d4313098b704861a105fe34231c70a3901c"
 
 [[package]]
 name = "memchr"
-version = "2.7.1"
+version = "2.7.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "523dc4f511e55ab87b694dc30d0f820d60906ef06413f93d4d7a1385599cc149"
+checksum = "6c8640c5d730cb13ebd907d8d04b52f55ac9a2eec55b440c8892f40d56c76c1d"
 
 [[package]]
 name = "memoffset"
-version = "0.9.0"
+version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5a634b1c61a95585bd15607c6ab0c4e5b226e695ff2800ba0cdccddf208c406c"
+checksum = "488016bfae457b036d996092f6cb448677611ce4449e970ceaf42695203f218a"
 dependencies = [
  "autocfg",
 ]
@@ -360,7 +360,7 @@ dependencies = [
 [[package]]
 name = "mmtk"
 version = "0.23.0"
-source = "git+https://github.com/mmtk/mmtk-core.git?rev=86a94ca502594d078b35c29ea3d1d68b34f16a28#86a94ca502594d078b35c29ea3d1d68b34f16a28"
+source = "git+https://github.com/mmtk/mmtk-core.git?rev=dd84218933deab50196fc77828cc1446cb829881#dd84218933deab50196fc77828cc1446cb829881"
 dependencies = [
  "atomic",
  "atomic-traits",
@@ -395,12 +395,12 @@ dependencies = [
 [[package]]
 name = "mmtk-macros"
 version = "0.23.0"
-source = "git+https://github.com/mmtk/mmtk-core.git?rev=86a94ca502594d078b35c29ea3d1d68b34f16a28#86a94ca502594d078b35c29ea3d1d68b34f16a28"
+source = "git+https://github.com/mmtk/mmtk-core.git?rev=dd84218933deab50196fc77828cc1446cb829881#dd84218933deab50196fc77828cc1446cb829881"
 dependencies = [
  "proc-macro-error",
  "proc-macro2",
  "quote",
- "syn 2.0.52",
+ "syn 2.0.55",
 ]
 
 [[package]]
@@ -530,9 +530,9 @@ dependencies = [
 
 [[package]]
 name = "rayon"
-version = "1.9.0"
+version = "1.10.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e4963ed1bc86e4f3ee217022bd855b297cef07fb9eac5dfa1f788b220b49b3bd"
+checksum = "b418a60154510ca1a002a752ca9714984e21e4241e804d32555251faf8b78ffa"
 dependencies = [
  "either",
  "rayon-core",
@@ -550,9 +550,9 @@ dependencies = [
 
 [[package]]
 name = "regex"
-version = "1.10.3"
+version = "1.10.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b62dbe01f0b06f9d8dc7d49e05a0785f153b00b2c227856282f671e0318c9b15"
+checksum = "c117dbdfde9c8308975b6a18d71f3f385c89461f7b3fb054288ecf2a2058ba4c"
 dependencies = [
  "aho-corasick",
  "memchr",
@@ -573,9 +573,9 @@ dependencies = [
 
 [[package]]
 name = "regex-syntax"
-version = "0.8.2"
+version = "0.8.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c08c74e62047bb2de4ff487b251e4a92e24f48745648451635cec7d591162d9f"
+checksum = "adad44e29e4c806119491a7f06f03de4d1af22c3a680dd47f1e6e179439d1f56"
 
 [[package]]
 name = "rustc_version"
@@ -647,7 +647,7 @@ dependencies = [
  "proc-macro2",
  "quote",
  "rustversion",
- "syn 2.0.52",
+ "syn 2.0.55",
 ]
 
 [[package]]
@@ -663,9 +663,9 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "2.0.52"
+version = "2.0.55"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b699d15b36d1f02c3e7c69f8ffef53de37aefae075d8488d4ba1a7788d574a07"
+checksum = "002a1b3dbf967edfafc32655d0f377ab0bb7b994aa1d32c8cc7e9b8bf3ebb8f0"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -713,7 +713,7 @@ checksum = "c61f3ba182994efc43764a46c018c347bc492c79f024e705f46567b418f6d4f7"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.52",
+ "syn 2.0.55",
 ]
 
 [[package]]
diff --git a/mmtk/Cargo.toml b/mmtk/Cargo.toml
index c954fe1..6a1bca5 100644
--- a/mmtk/Cargo.toml
+++ b/mmtk/Cargo.toml
@@ -12,7 +12,7 @@ edition = "2021"
 # Metadata for the Ruby repository
 [package.metadata.ci-repos.ruby]
 repo = "mmtk/ruby" # This is used by actions/checkout, so the format is "owner/repo", not URL.
-rev = "ff16207cfbe2e54997e2111022185d1591605179"
+rev = "6d1596f7a4401d267d2b208c42521edc35020a8e  "
 
 [lib]
 name = "mmtk_ruby"
@@ -37,7 +37,7 @@ features = ["is_mmtk_object", "object_pinning"]
 
 # Uncomment the following lines to use mmtk-core from the official repository.
 git = "https://github.com/mmtk/mmtk-core.git"
-rev = "86a94ca502594d078b35c29ea3d1d68b34f16a28"
+rev = "dd84218933deab50196fc77828cc1446cb829881"
 
 # Uncomment the following line to use mmtk-core from a local repository.
 #path = "../../mmtk-core"