diff --git a/.evergreen/abi-compliance-check-setup.sh b/.evergreen/abi-compliance-check-setup.sh
new file mode 100755
index 0000000000..fcbc97a56e
--- /dev/null
+++ b/.evergreen/abi-compliance-check-setup.sh
@@ -0,0 +1,41 @@
+#!/usr/bin/env bash
+
+set -o errexit
+set -o pipefail
+
+declare working_dir
+working_dir="$(pwd)"
+
+export PATH
+PATH="${working_dir:?}/install/bin:${PATH:-}"
+
+# Install prefix to use for ABI compatibility scripts.
+[[ -d "${working_dir}/install" ]]
+
+declare parallel_level
+parallel_level="$(("$(nproc)" + 1))"
+
+# Obtain abi-compliance-checker.
+echo "Fetching abi-compliance-checker..."
+[[ -d checker ]] || {
+  git clone -b "2.3" --depth 1 https://github.com/lvc/abi-compliance-checker.git checker
+  pushd checker
+  make -j "${parallel_level:?}" --no-print-directory install prefix="${working_dir:?}/install"
+  popd # checker
+} >/dev/null
+echo "Fetching abi-compliance-checker... done."
+
+# Obtain ctags.
+echo "Fetching ctags..."
+[[ -d ctags ]] || {
+  git clone -b "v6.0.0" --depth 1 https://github.com/universal-ctags/ctags.git ctags
+  pushd ctags
+  ./autogen.sh
+  ./configure --prefix="${working_dir}/install"
+  make -j "${parallel_level:?}"
+  make install
+  popd # ctags
+} >/dev/null
+echo "Fetching ctags... done."
+
+command -V abi-compliance-checker
diff --git a/.evergreen/abi-compliance-check-test.sh b/.evergreen/abi-compliance-check-test.sh
new file mode 100755
index 0000000000..d359840b89
--- /dev/null
+++ b/.evergreen/abi-compliance-check-test.sh
@@ -0,0 +1,146 @@
+#!/usr/bin/env bash
+
+set -o errexit
+set -o pipefail
+
+declare working_dir
+working_dir="$(pwd)"
+
+declare base current
+base="$(cat base-commit.txt)"
+current="$(cat current-commit.txt)"
+
+export PATH
+PATH="${working_dir:?}/install/bin:${PATH:-}"
+
+# Remove 'r' prefix in version string.
+declare old_ver new_ver
+old_ver="${base:1}-base"
+new_ver="${current:1}-current"
+
+command -V abi-compliance-checker >/dev/null
+
+mkdir cxx-abi cxx-noabi
+
+cat >cxx-abi/old.xml <<DOC
+<version>
+  ${old_ver:?}
+</version>
+
+<headers>
+  ../install/old/include/bsoncxx/
+  ../install/old/include/mongocxx/
+</headers>
+
+<skip_headers>
+  /v_noabi/
+</skip_headers>
+
+<libs>
+  ../install/old/lib
+</libs>
+
+<add_include_paths>
+  ../install/old/include/
+</add_include_paths>
+
+<skip_including>
+  bsoncxx/enums/
+  /config/
+</skip_including>
+DOC
+
+cat >cxx-abi/new.xml <<DOC
+<version>
+  ${new_ver:?}
+</version>
+
+<headers>
+  ../install/new/include/mongocxx/
+  ../install/new/include/bsoncxx/
+</headers>
+
+<skip_headers>
+  /v_noabi/
+</skip_headers>
+
+<libs>
+  ../install/new/lib
+</libs>
+
+<add_include_paths>
+  ../install/new/include/
+</add_include_paths>
+
+<skip_including>
+  bsoncxx/enums/
+  /config/
+</skip_including>
+DOC
+
+cat >cxx-noabi/old.xml <<DOC
+<version>
+  ${old_ver:?}
+</version>
+
+<headers>
+  ../install/old/include/bsoncxx/v_noabi
+  ../install/old/include/mongocxx/v_noabi
+</headers>
+
+<libs>
+  ../install/old/lib
+</libs>
+
+<add_include_paths>
+  ../install/old/include/
+</add_include_paths>
+
+<skip_including>
+  bsoncxx/enums/
+  /config/
+</skip_including>
+DOC
+
+cat >cxx-noabi/new.xml <<DOC
+<version>
+  ${new_ver:?}
+</version>
+
+<headers>
+  ../install/new/include/bsoncxx/v_noabi
+  ../install/new/include/mongocxx/v_noabi
+</headers>
+
+<libs>
+  ../install/new/lib
+</libs>
+
+<add_include_paths>
+  ../install/new/include/
+</add_include_paths>
+
+<skip_including>
+  bsoncxx/enums/
+  /config/
+</skip_including>
+DOC
+
+# Allow task to upload the HTML report despite failed status.
+echo "Generating stable ABI report..."
+pushd cxx-abi
+if ! abi-compliance-checker -lib mongo-cxx-driver -old old.xml -new new.xml; then
+  : # CXX-2812: enable code below once stable ABI symbols exist in the base commit libraries.
+  # declare status
+  # status='{"status":"failed", "type":"test", "should_continue":true, "desc":"abi-compliance-checker emitted one or more errors"}'
+  # curl -sS -d "${status:?}" -H "Content-Type: application/json" -X POST localhost:2285/task_status || true
+fi
+popd # cxx-abi
+echo "Generating stable ABI report... done."
+
+# Also create a report for the unstable ABI. Errors are expected and OK.
+echo "Generating unstable ABI report..."
+pushd cxx-noabi
+abi-compliance-checker -lib mongo-cxx-driver -old old.xml -new new.xml || true
+popd # cxx-noabi
+echo "Generating unstable ABI report... done."
diff --git a/.evergreen/abi-prohibited-symbols-test.sh b/.evergreen/abi-prohibited-symbols-test.sh
new file mode 100755
index 0000000000..3fd77b3a96
--- /dev/null
+++ b/.evergreen/abi-prohibited-symbols-test.sh
@@ -0,0 +1,44 @@
+#!/usr/bin/env bash
+
+set -o errexit
+set -o pipefail
+
+command -V nm >/dev/null
+
+declare -a libs
+libs=(
+  install/new/lib/libbsoncxx.so
+  install/new/lib/libmongocxx.so
+)
+
+for lib in "${libs[@]}"; do
+  [[ -f "${lib:?}" ]] || {
+    echo "error: missing ${lib:?}"
+    exit 1
+  } 1>&2
+done
+
+# Patterns for library symbols to check.
+match_pattern=(
+  -e '(bsoncxx|mongocxx)::'
+)
+
+# Patterns for bad symbols.
+bad_pattern=(
+  -e '(bsoncxx|mongocxx)::(.+::)?detail::'
+  -e '(bsoncxx|mongocxx)::(.+::)?test::'
+)
+
+# Ensure implementation details do not leak into the ABI.
+mapfile -t bad_symbols < <(
+  nm --demangle --dynamic --defined-only --extern-only --just-symbols "${libs[@]}" |
+    grep -E "${match_pattern[@]}" |
+    grep -E "${bad_pattern[@]}"
+)
+
+# Print list of bad symbols.
+(("${#bad_symbols[*]}" == 0)) || {
+  echo "error: found ${#bad_symbols[@]} prohibited symbols in exported ABI:"
+  printf " - %s\n" "${bad_symbols[@]}"
+  exit 1
+} 1>&2
diff --git a/.evergreen/abi-stability-setup.sh b/.evergreen/abi-stability-setup.sh
new file mode 100755
index 0000000000..39ccdcf02a
--- /dev/null
+++ b/.evergreen/abi-stability-setup.sh
@@ -0,0 +1,115 @@
+#!/usr/bin/env bash
+
+set -o errexit
+set -o pipefail
+
+: "${cxx_standard:?}" # Set by abi-stability-checks-* build variant definition.
+
+command -V git >/dev/null
+
+# Files prepared by EVG config.
+[[ -d "mongoc" ]] || {
+  echo "missing mongoc" 1>&2
+  exit 1
+}
+[[ -d "mongo-cxx-driver" ]] || {
+  echo "missing mongo-cxx-driver" 1>&2
+  exit 1
+}
+
+declare working_dir
+working_dir="$(pwd)"
+
+declare cmake_binary
+# shellcheck source=/dev/null
+. ./mongoc/.evergreen/scripts/find-cmake-latest.sh
+cmake_binary="$(find_cmake_latest)"
+command -V "${cmake_binary:?}"
+
+# To use a different base commit, replace `--abbrev 0` with the intended commit.
+# Note: EVG treat all changes relative to the EVG base commit as staged changes!
+declare base current
+base="$(git -C mongo-cxx-driver describe --tags --abbrev=0)"
+current="$(git -C mongo-cxx-driver describe --tags)"
+
+echo "Old Version (Base): ${base:?}"
+echo "New Version (Current): ${current:?}"
+
+printf "%s" "${base:?}" >base-commit.txt
+printf "%s" "${current:?}" >current-commit.txt
+
+# Remove 'r' prefix in version string.
+declare old_ver new_ver
+old_ver="${base:1}"
+new_ver="${current:1}"
+
+declare parallel_level
+parallel_level="$(("$(nproc)" + 1))"
+
+# Use Ninja if available.
+if command -V ninja; then
+  export CMAKE_GENERATOR
+  CMAKE_GENERATOR="Ninja"
+else
+  export CMAKE_BUILD_PARALLEL_LEVEL
+  CMAKE_BUILD_PARALLEL_LEVEL="${parallel_level:?}"
+fi
+
+# Use ccache if available.
+if command -V ccache; then
+  export CMAKE_C_COMPILER_LAUNCHER CMAKE_CXX_COMPILER_LAUNCHER
+  CMAKE_C_COMPILER_LAUNCHER="ccache"
+  CMAKE_CXX_COMPILER_LAUNCHER="ccache"
+fi
+
+# Install prefix to use for ABI compatibility scripts.
+mkdir -p "${working_dir}/install"
+
+# As encouraged by ABI compatibility checkers.
+export CFLAGS CXXFLAGS
+CFLAGS="-g -Og"
+CXXFLAGS="-g -Og"
+
+# Build and install the base commit first.
+git -C mongo-cxx-driver stash push -u
+git -C mongo-cxx-driver reset --hard "${base:?}"
+
+# Install old (base) to install/old.
+echo "Building old libraries..."
+{
+  "${cmake_binary:?}" \
+    -S mongo-cxx-driver \
+    -B build/old \
+    -DCMAKE_INSTALL_PREFIX="install/old" \
+    -DCMAKE_PREFIX_PATH="${working_dir:?}/mongoc" \
+    -DBUILD_VERSION="${old_ver:?}-base" \
+    -DCMAKE_CXX_STANDARD="${cxx_standard:?}"
+  "${cmake_binary:?}" --build build/old
+  "${cmake_binary:?}" --install build/old
+} &>old.log || {
+  cat old.log 1>&2
+  exit 1
+}
+echo "Building old libraries... done."
+
+# Restore all pending changes.
+git -C mongo-cxx-driver reset --hard "HEAD@{1}"
+git -C mongo-cxx-driver stash pop -q || true # Only patch builds have stashed changes.
+
+# Install new (current) to install/new.
+echo "Building new libraries..."
+{
+  "${cmake_binary:?}" \
+    -S mongo-cxx-driver \
+    -B build/new \
+    -DCMAKE_INSTALL_PREFIX="install/new" \
+    -DCMAKE_PREFIX_PATH="${working_dir:?}/mongoc" \
+    -DBUILD_VERSION="${new_ver:?}-current" \
+    -DCMAKE_CXX_STANDARD="${cxx_standard:?}"
+  "${cmake_binary:?}" --build build/new
+  "${cmake_binary:?}" --install build/new
+} &>new.log || {
+  cat new.log 1>&2
+  exit 1
+}
+echo "Building new libraries... done."
diff --git a/.evergreen/abidiff-setup.sh b/.evergreen/abidiff-setup.sh
new file mode 100755
index 0000000000..c39f15a85b
--- /dev/null
+++ b/.evergreen/abidiff-setup.sh
@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+
+set -o errexit
+set -o pipefail
+
+declare working_dir
+working_dir="$(pwd)"
+
+export PATH
+PATH="${working_dir:?}/install/bin:${PATH:-}"
+
+# Install prefix to use for ABI compatibility scripts.
+[[ -d "${working_dir}/install" ]]
+
+if command -V abidiff 2>/dev/null; then
+  exit # Already available.
+fi
+
+# Expected to be run on Ubuntu.
+echo "Installing abigail-tools..."
+sudo apt-get install -q -y abigail-tools >/dev/null
+echo "Installing abigail-tools... done."
+
+command -V abidiff
diff --git a/.evergreen/abidiff-test.sh b/.evergreen/abidiff-test.sh
new file mode 100755
index 0000000000..bac301f3c2
--- /dev/null
+++ b/.evergreen/abidiff-test.sh
@@ -0,0 +1,79 @@
+#!/usr/bin/env bash
+
+set -o errexit
+set -o pipefail
+
+declare working_dir
+working_dir="$(pwd)"
+
+export PATH
+PATH="${working_dir:?}/install/bin:${PATH:-}"
+
+declare -a common_flags
+flags=(
+  --headers-dir1 install/old/include
+  --headers-dir2 install/new/include
+  --non-reachable-types
+  --fail-no-debug-info
+)
+
+declare -a abi_flags=("${common_flags[@]}" --suppressions cxx-abi/abignore)
+declare -a noabi_flags=("${common_flags[@]}" --suppressions cxx-noabi/abignore)
+
+command -V abidiff >/dev/null
+
+mkdir cxx-abi cxx-noabi
+
+cat >cxx-abi/abignore <<DOC
+[suppress_type]
+name_not_regexp = ^(bsoncxx|mongocxx)::v[[:digit:]]+::
+
+[suppress_function]
+name_not_regexp = ^(bsoncxx|mongocxx)::v[[:digit:]]+::
+
+[suppress_variable]
+name_not_regexp = ^(bsoncxx|mongocxx)::v[[:digit:]]+::
+DOC
+
+cat >cxx-noabi/abignore <<DOC
+[suppress_type]
+name_regexp = ^(bsoncxx|mongocxx)::v[[:digit:]]+::
+
+[suppress_function]
+name_regexp = ^(bsoncxx|mongocxx)::v[[:digit:]]+::
+
+[suppress_variable]
+name_regexp = ^(bsoncxx|mongocxx)::v[[:digit:]]+::
+DOC
+
+# Allow task to upload the diff reports despite failed status.
+echo "Comparing stable ABI for bsoncxx..."
+if ! abidiff "${abi_flags[@]}" install/old/lib/libbsoncxx.so install/new/lib/libbsoncxx.so &>cxx-abi/bsoncxx.txt; then
+  declare status
+  status='{"status":"failed", "type":"test", "should_continue":true, "desc":"abidiff returned an error for bsoncxx (stable)"}'
+  curl -sS -d "${status:?}" -H "Content-Type: application/json" -X POST localhost:2285/task_status || true
+fi
+echo "Comparing stable ABI for bsoncxx... done."
+
+# Allow task to upload the diff reports despite failed status.
+echo "Comparing stable ABI for mongocxx..."
+if ! abidiff "${abi_flags[@]}" install/old/lib/libmongocxx.so install/new/lib/libmongocxx.so &>cxx-abi/mongocxx.txt; then
+  declare status
+  status='{"status":"failed", "type":"test", "should_continue":true, "desc":"abidiff returned an error for mongocxx (stable)"}'
+  curl -sS -d "${status:?}" -H "Content-Type: application/json" -X POST localhost:2285/task_status || true
+fi
+echo "Comparing stable ABI for mongocxx... done."
+
+echo "Comparing unstable ABI for bsoncxx..."
+abidiff "${noabi_flags[@]}" install/old/lib/libbsoncxx.so install/new/lib/libbsoncxx.so &>cxx-noabi/bsoncxx.txt || true
+echo "Comparing unstable ABI for bsoncxx... done."
+
+echo "Comparing unstable ABI for mongocxx..."
+abidiff "${noabi_flags[@]}" install/old/lib/libmongocxx.so install/new/lib/libmongocxx.so &>cxx-noabi/mongocxx.txt || true
+echo "Comparing unstable ABI for mongocxx... done."
+
+# Ensure files have content even when abidiff produces no output.
+printf "\n" >>cxx-abi/bsoncxx.txt
+printf "\n" >>cxx-abi/mongocxx.txt
+printf "\n" >>cxx-noabi/bsoncxx.txt
+printf "\n" >>cxx-noabi/mongocxx.txt
diff --git a/.mci.yml b/.mci.yml
index b0df280423..0f9592bae1 100644
--- a/.mci.yml
+++ b/.mci.yml
@@ -56,6 +56,103 @@ variables:
 #######################################
 
 functions:
+    "abi-compliance-check":
+        - command: subprocess.exec
+          type: setup
+          params:
+            binary: bash
+            args: [mongo-cxx-driver/.evergreen/abi-compliance-check-setup.sh]
+        - command: subprocess.exec
+          type: test
+          params:
+            binary: bash
+            args: [mongo-cxx-driver/.evergreen/abi-compliance-check-test.sh]
+        - command: s3.put
+          type: system
+          params:
+            aws_key: ${aws_key}
+            aws_secret: ${aws_secret}
+            bucket: mciuploads
+            content_type: text/html
+            display_name: "ABI Compliance Check (Stable): "
+            local_files_include_filter: cxx-abi/compat_reports/**/compat_report.html
+            permissions: public-read
+            remote_file: mongo-cxx-driver/${branch_name}/${revision}/${version_id}/${build_id}/${execution}/abi-compliance-check/abi/
+        - command: s3.put
+          type: system
+          params:
+            aws_key: ${aws_key}
+            aws_secret: ${aws_secret}
+            bucket: mciuploads
+            content_type: text/plain
+            display_name: "ABI Compliance Check (Stable): "
+            local_files_include_filter: cxx-abi/logs/**/log.txt
+            permissions: public-read
+            remote_file: mongo-cxx-driver/${branch_name}/${revision}/${version_id}/${build_id}/${execution}/abi-compliance-check/abi/
+        - command: s3.put
+          type: system
+          params:
+            aws_key: ${aws_key}
+            aws_secret: ${aws_secret}
+            bucket: mciuploads
+            content_type: text/html
+            display_name: "ABI Compliance Check (Unstable): "
+            local_files_include_filter: cxx-noabi/compat_reports/**/compat_report.html
+            permissions: public-read
+            remote_file: mongo-cxx-driver/${branch_name}/${revision}/${version_id}/${build_id}/${execution}/abi-compliance-check/noabi/
+        - command: s3.put
+          type: system
+          params:
+            aws_key: ${aws_key}
+            aws_secret: ${aws_secret}
+            bucket: mciuploads
+            content_type: text/plain
+            display_name: "ABI Compliance Check (Unstable): "
+            local_files_include_filter: cxx-noabi/logs/**/log.txt
+            permissions: public-read
+            remote_file: mongo-cxx-driver/${branch_name}/${revision}/${version_id}/${build_id}/${execution}/abi-compliance-check/noabi/
+
+    "abidiff":
+        - command: subprocess.exec
+          type: setup
+          params:
+            binary: bash
+            args: [mongo-cxx-driver/.evergreen/abidiff-setup.sh]
+        - command: subprocess.exec
+          type: test
+          params:
+            binary: bash
+            args: [mongo-cxx-driver/.evergreen/abidiff-test.sh]
+        - command: s3.put
+          type: system
+          params:
+            aws_key: ${aws_key}
+            aws_secret: ${aws_secret}
+            bucket: mciuploads
+            content_type: text/plain
+            display_name: "abidiff (Stable): "
+            local_files_include_filter: cxx-abi/*.txt
+            permissions: public-read
+            remote_file: mongo-cxx-driver/${branch_name}/${revision}/${version_id}/${build_id}/${execution}/abidiff/abi/
+        - command: s3.put
+          type: system
+          params:
+            aws_key: ${aws_key}
+            aws_secret: ${aws_secret}
+            bucket: mciuploads
+            content_type: text/plain
+            display_name: "abidiff (Unstable): "
+            local_files_include_filter: cxx-noabi/*.txt
+            permissions: public-read
+            remote_file: mongo-cxx-driver/${branch_name}/${revision}/${version_id}/${build_id}/${execution}/abidiff/noabi/
+
+    "abi-prohibited-symbols":
+        - command: subprocess.exec
+          type: test
+          params:
+            binary: bash
+            args: [mongo-cxx-driver/.evergreen/abi-prohibited-symbols-test.sh]
+
     "setup":
         - command: shell.exec
           params:
@@ -563,6 +660,22 @@ post:
 #######################################
 
 tasks:
+    - name: abi-compliance-check
+      tags: ["abi-stability", "abi-compliance-check"]
+      run_on: "ubuntu2204-large"
+      commands:
+        - func: "abi-compliance-check"
+    - name: abidiff
+      tags: ["abi-stability", "abidiff"]
+      run_on: "ubuntu2204-large"
+      commands:
+        - func: "abidiff"
+    - name: abi-prohibited-symbols
+      tags: ["abi-stability", "abi-prohibited-symbols"]
+      run_on: "ubuntu2204-large"
+      commands:
+        - func: "abi-prohibited-symbols"
+
     - name: lint
       run_on: ubuntu1804-large
       commands:
@@ -987,6 +1100,27 @@ tasks:
               ./build/src/mongocxx/test/test_driver "atlas search indexes prose tests"
 
 task_groups:
+  - name: tg-abi-stability
+    max_hosts: -1
+    setup_task_can_fail_task: true
+    setup_task:
+      - command: git.get_project
+        params:
+          directory: "mongo-cxx-driver"
+      - func: install_c_driver
+      - command: subprocess.exec
+        params:
+          binary: bash
+          args: [mongo-cxx-driver/.evergreen/abi-stability-setup.sh]
+          include_expansions_in_env: [cxx_standard]
+    tasks: [".abi-stability"]
+    teardown_task_can_fail_task: true
+    teardown_task:
+      - command: subprocess.exec
+        params:
+          binary: bash
+          args: [-c, rm -rf *]
+
   - name: test_atlas_task_group_search_indexes
     setup_group:
       - func: "setup"
@@ -1023,6 +1157,29 @@ task_groups:
 #######################################
 
 buildvariants:
+    ##########################
+    #  ABI Stability Checks  #
+    ##########################
+    - name: abi-stability-polyfill
+      display_name: "ABI Stability Checks (polyfill)"
+      expansions:
+        cxx_standard: 11 # Use a polyfill library.
+      tasks:
+        - "tg-abi-stability"
+      display_tasks:
+        - name: "ABI Stability Checks (polyfill)"
+          execution_tasks: [".abi-stability"]
+
+    - name: abi-stability-stdlib
+      display_name: "ABI Stability Checks (stdlib)"
+      expansions:
+        cxx_standard: 17 # Use the stdlib.
+      tasks:
+        - "tg-abi-stability"
+      display_tasks:
+        - name: "ABI Stability Checks (stdlib)"
+          execution_tasks: [".abi-stability"]
+
     #######################################
     #  Standard MongoDB Integration Tests #
     #######################################