diff --git a/.github/workflows/code-coverage.yml b/.github/workflows/code-coverage.yml
index cb36d3e5a5..0d794e74e1 100644
--- a/.github/workflows/code-coverage.yml
+++ b/.github/workflows/code-coverage.yml
@@ -24,13 +24,13 @@ jobs:
       DISABLE_CXX_SHARED: 'true'
       
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
       with:
         submodules: true
       if: github.event_name != 'schedule'
 
     - name: Checkout develop branch
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
       with:
         submodules: true
         ref: develop
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
new file mode 100644
index 0000000000..2c72e6622d
--- /dev/null
+++ b/.github/workflows/codeql.yml
@@ -0,0 +1,94 @@
+# For most projects, this workflow file will not need changing; you simply need
+# to commit it to your repository.
+#
+# You may wish to alter this file to override the set of languages analyzed,
+# or to provide custom queries or build logic.
+#
+# ******** NOTE ********
+# We have attempted to detect the languages in your repository. Please check
+# the `language` matrix defined below to confirm you have the correct set of
+# supported CodeQL languages.
+#
+name: "CodeQL"
+
+on:
+  workflow_dispatch:
+  push:
+    branches: [ "main", "develop" ]
+  pull_request:
+    branches: [ "main", "develop" ]
+  schedule:
+    - cron: '23 6 * * 0'
+
+jobs:
+  analyze:
+    name: Analyze
+    # Runner size impacts CodeQL analysis time. To learn more, please see:
+    #   - https://gh.io/recommended-hardware-resources-for-running-codeql
+    #   - https://gh.io/supported-runners-and-hardware-resources
+    #   - https://gh.io/using-larger-runners
+    # Consider using larger runners for possible analysis time improvements.
+    runs-on: ubuntu-latest
+    container: helics/buildenv:ubuntu22.04-default-builder
+    timeout-minutes: 60
+    defaults:
+      run:
+        shell: bash
+    env:
+      CMAKE_GENERATOR: Unix Makefiles
+      MAKEFLAGS: '-j 4'
+      DISABLE_INTERFACES: 'Java'
+      DISABLE_EXAMPLES: 'true'
+      DISABLE_CXX_SHARED: 'true'
+    permissions:
+      actions: read
+      contents: read
+      security-events: write
+
+    strategy:
+      fail-fast: false
+      matrix:
+        language: [ 'c-cpp']
+        # CodeQL supports [ 'c-cpp', 'csharp', 'go', 'java-kotlin', 'javascript-typescript', 'python', 'ruby', 'swift' ]
+        # Use only 'java-kotlin' to analyze code written in Java, Kotlin or both
+        # Use only 'javascript-typescript' to analyze code written in JavaScript, TypeScript or both
+        # Learn more about CodeQL language support at https://aka.ms/codeql-docs/language-support
+
+    steps:
+    - name: Checkout repository
+      uses: actions/checkout@v4
+
+    # tell git that the workspace directory is safe
+    - run: |
+        git config --global --add safe.directory ${GITHUB_WORKSPACE}
+
+    # Initializes the CodeQL tools for scanning.
+    - name: Initialize CodeQL
+      uses: github/codeql-action/init@v3
+      with:
+        languages: ${{ matrix.language }}
+        # If you wish to specify custom queries, you can do so here or in a config file.
+        # By default, queries listed here will override any specified in a config file.
+        # Prefix the list here with "+" to use these queries and those in the config file.
+
+        # For more details on CodeQL's query packs, refer to: https://docs.github.com/en/code-security/code-scanning/automatically-scanning-your-code-for-vulnerabilities-and-errors/configuring-code-scanning#using-queries-in-ql-packs
+        # queries: security-extended,security-and-quality
+
+
+    # ℹ️ Command-line programs to run using the OS shell.
+    # 📚 See https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idstepsrun
+
+    #   If the Autobuild fails above, remove it and uncomment the following three lines.
+    #   modify them (or add more) to build your code if your project, please refer to the EXAMPLE below for guidance.
+
+    - run: |
+        echo "Run, Build Application using script"
+        unset VCPKG_ROOT
+        source scripts/setup-helics-ci-options.sh
+        mkdir -p build && cd build
+        ../scripts/ci-build.sh
+
+    - name: Perform CodeQL Analysis
+      uses: github/codeql-action/analyze@v3
+      with:
+        category: "/language:${{matrix.language}}"
diff --git a/src/helics/application_api/Subscriptions.hpp b/src/helics/application_api/Subscriptions.hpp
index c41082503b..9f5e2528a4 100644
--- a/src/helics/application_api/Subscriptions.hpp
+++ b/src/helics/application_api/Subscriptions.hpp
@@ -214,8 +214,10 @@ class VectorSubscription2d {
         static_assert(
             std::is_base_of<ValueFederate, std::remove_reference_t<decltype(*valueFed)>>::value,
             "Second argument must be a pointer to a ValueFederate");
-        ids.reserve(count_x * count_y);
-        vals.resize(count_x * count_y, defValue);
+        std::size_t arrayCount =
+            static_cast<std::size_t>(count_x) * static_cast<std::size_t>(count_y);
+        ids.reserve(arrayCount);
+        vals.resize(arrayCount, defValue);
 
         for (auto ind_x = startIndex_x; ind_x < startIndex_x + count_x; ++ind_x) {
             for (auto ind_y = startIndex_y; ind_y < startIndex_y + count_y; ++ind_y) {
diff --git a/src/helics/application_api/ValueConverter.cpp b/src/helics/application_api/ValueConverter.cpp
index 42818f7ef1..3ee0be300b 100644
--- a/src/helics/application_api/ValueConverter.cpp
+++ b/src/helics/application_api/ValueConverter.cpp
@@ -304,7 +304,7 @@ namespace detail {
                 // making use of array oriented access for complex numbers
                 // See https://en.cppreference.com/w/cpp/numeric/complex
                 checks::swapBytes<8>(reinterpret_cast<std::byte*>(&v));
-                checks::swapBytes<8>(reinterpret_cast<std::byte*>(&v) + sizeof(double));
+                checks::swapBytes<8>(reinterpret_cast<std::byte*>(&v) + 8);
             }
         }
     }