diff --git a/.github/workflows/c-coverage.yml b/.github/workflows/c-coverage.yml
index 19bfe5d..ccc9a64 100644
--- a/.github/workflows/c-coverage.yml
+++ b/.github/workflows/c-coverage.yml
@@ -12,7 +12,7 @@ on: # yamllint disable-line rule:truthy
 jobs:
   coverage:
     name: C/C++ CMake CI Coverage
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
 
     steps:
       - name: Checkout repository
diff --git a/.github/workflows/clang-format.yml b/.github/workflows/clang-format.yml
index 960ec55..1bf4fc8 100644
--- a/.github/workflows/clang-format.yml
+++ b/.github/workflows/clang-format.yml
@@ -12,7 +12,7 @@ on: # yamllint disable-line rule:truthy
 jobs:
   lint:
     name: clang-format style check
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
 
     steps:
       - name: Checkout repository
@@ -21,12 +21,15 @@ jobs:
       - name: Install dependencies
         # yamllint disable rule:line-length
         run: |
-          wget -O - https://apt.llvm.org/llvm-snapshot.gpg.key | sudo apt-key add -
-          sudo apt-add-repository "deb http://apt.llvm.org/jammy/ llvm-toolchain-jammy main"
+          sudo mkdir -p /etc/apt/keyrings
+          curl -fsSL https://apt.llvm.org/llvm-snapshot.gpg.key \
+          | sudo gpg --dearmor -o /etc/apt/keyrings/llvm-snapshot.gpg
+          echo "deb [signed-by=/etc/apt/keyrings/llvm-snapshot.gpg] http://apt.llvm.org/resolute/ llvm-toolchain-resolute-22 main" \
+          | sudo tee /etc/apt/sources.list.d/llvm.list && \
           sudo apt-get -y update
-          sudo apt-get -y install --no-install-recommends --no-install-suggests clang-format-19
-          sudo update-alternatives --install /usr/bin/clang-format clang-format $(which clang-format-19) 100
-          sudo update-alternatives --set clang-format $(update-alternatives --list clang-format | grep clang-format-19)
+          sudo apt-get -y install --no-install-recommends --no-install-suggests clang-format-22
+          sudo update-alternatives --install /usr/bin/clang-format clang-format $(which clang-format-22) 100
+          sudo update-alternatives --set clang-format $(update-alternatives --list clang-format | grep clang-format-22)
           # yamllint enable rule:line-length
 
       - name: Check Tools
diff --git a/.github/workflows/cppcheck.yml b/.github/workflows/cppcheck.yml
index 2085706..7179d05 100644
--- a/.github/workflows/cppcheck.yml
+++ b/.github/workflows/cppcheck.yml
@@ -13,7 +13,7 @@ on: # yamllint disable-line rule:truthy
 jobs:
   lint:
     name: CppCheck Lint
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
 
     steps:
       - name: Checkout repository
diff --git a/.github/workflows/docker-image.yml b/.github/workflows/docker-image.yml
index add32e8..f56d36c 100644
--- a/.github/workflows/docker-image.yml
+++ b/.github/workflows/docker-image.yml
@@ -18,7 +18,7 @@ jobs:
 
   build:
     name: "Build Docker images"
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     steps:
       - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
 
@@ -73,7 +73,7 @@ jobs:
 
   lint:
     name: "Run in docker: LINT"
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     needs: build
     steps:
       - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
@@ -98,7 +98,7 @@ jobs:
 
   test:
     name: "Run in docker: TEST"
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     needs: build
     steps:
       - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
@@ -124,7 +124,7 @@ jobs:
   # yamllint disable rule:line-length
   # security:
   #   name: "Snyk Container"
-  #   runs-on: ubuntu-24.04
+  #   runs-on: ubuntu-26.04
   #   needs: build
   #   permissions:
   #     actions: read
@@ -173,7 +173,7 @@ jobs:
 
   scan:
     name: "Trivy"
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     needs: build
     permissions:
       actions: read
diff --git a/.github/workflows/gitleaks.yml b/.github/workflows/gitleaks.yml
index fe87491..48a3da5 100644
--- a/.github/workflows/gitleaks.yml
+++ b/.github/workflows/gitleaks.yml
@@ -19,7 +19,7 @@ on: # yamllint disable-line rule:truthy
 jobs:
   scan:
     name: gitleaks
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     steps:
       - uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
         with:
diff --git a/.github/workflows/make-coverage-html.yml b/.github/workflows/make-coverage-html.yml
index 319da88..12bf923 100644
--- a/.github/workflows/make-coverage-html.yml
+++ b/.github/workflows/make-coverage-html.yml
@@ -15,7 +15,7 @@ on: # yamllint disable-line rule:truthy
 jobs:
   make-coverage-html:
     name: "Run make coverage/html and verify coverage HTML"
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     steps:
       - name: Checkout repository
         uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
diff --git a/.github/workflows/markdown-lint.yml b/.github/workflows/markdown-lint.yml
index a80dc93..4cc5157 100644
--- a/.github/workflows/markdown-lint.yml
+++ b/.github/workflows/markdown-lint.yml
@@ -15,7 +15,7 @@ permissions:
 jobs:
   markdownlint:
     name: Markdown Lint
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
 
     strategy:
       matrix:
diff --git a/.github/workflows/sonarcloud.yml b/.github/workflows/sonarcloud.yml
index 203e947..852a2f4 100644
--- a/.github/workflows/sonarcloud.yml
+++ b/.github/workflows/sonarcloud.yml
@@ -11,7 +11,7 @@ on: # yamllint disable-line rule:truthy
 jobs:
   build:
     name: SonarCloud build and run sonar-scanner
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     env:
       # Directory where build-wrapper output will be placed
       BUILD_WRAPPER_OUT_DIR: build
diff --git a/.github/workflows/yamllint.yml b/.github/workflows/yamllint.yml
index bad6388..ff60197 100644
--- a/.github/workflows/yamllint.yml
+++ b/.github/workflows/yamllint.yml
@@ -13,7 +13,7 @@ on: # yamllint disable-line rule:truthy
 jobs:
   lint:
     name: YAML lint
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     steps:
       - name: Checkout repository
         uses: actions/checkout@df4cb1c069e1874edd31b4311f1884172cec0e10 # v6
diff --git a/Dockerfile b/Dockerfile
index 9398284..d01fdf1 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-ARG BASE_IMAGE_VERSION=ubuntu:noble-20260509.1
+ARG BASE_IMAGE_VERSION=ubuntu:26.04
 FROM ${BASE_IMAGE_VERSION} AS init
 
 ENV WORKDIR=/app
@@ -34,7 +34,7 @@ RUN apt-get -y update && \
   ca-certificates curl git ninja-build unzip zip && \
   rm -rf /var/lib/apt/lists/* && \
   mkdir /opt/vcpkg && \
-  git clone --branch ${VCPKG_VERSION} https://github.com/microsoft/vcpkg "${VCPKG_ROOT}" && \
+  git clone --branch "${VCPKG_VERSION}" https://github.com/microsoft/vcpkg "${VCPKG_ROOT}" && \
   /opt/vcpkg/bootstrap-vcpkg.sh && \
   ln -s /opt/vcpkg/vcpkg /usr/local/bin/vcpkg && \
   rm -rf /var/lib/apt/lists/* && \
@@ -69,12 +69,15 @@ FROM builder AS lint
 RUN apt-get update && \
   apt-get -y install --no-install-recommends --no-install-suggests gnupg software-properties-common && \
   rm -rf /var/lib/apt/lists/*
-ADD https://apt.llvm.org/llvm-snapshot.gpg.key llvm-snapshot.gpg.key
-RUN apt-key add llvm-snapshot.gpg.key && \
-  apt-add-repository -y "deb https://apt.llvm.org/plucky/ llvm-toolchain-plucky-20 main" && \
+
+RUN mkdir -p /etc/apt/keyrings && \
+  curl -fsSL https://apt.llvm.org/llvm-snapshot.gpg.key \
+  | gpg --dearmor -o /etc/apt/keyrings/llvm-snapshot.gpg && \
+  echo "deb [signed-by=/etc/apt/keyrings/llvm-snapshot.gpg] http://apt.llvm.org/resolute/ llvm-toolchain-resolute-22 main" \
+  | tee /etc/apt/sources.list.d/llvm.list && \
   apt-get -y update && \
-  apt-get -y install --no-install-recommends --no-install-suggests clang-format-19 && \
-  update-alternatives --install /usr/bin/clang-format clang-format $(which clang-format-19) 100 && \
+  apt-get -y install --no-install-recommends --no-install-suggests clang-format-22 && \
+  update-alternatives --install /usr/bin/clang-format clang-format $(which clang-format-22) 100 && \
   rm -rf /var/lib/apt/lists/*
 
 ADD https://deb.nodesource.com/setup_22.x nodesource_setup.sh
@@ -83,10 +86,16 @@ RUN bash nodesource_setup.sh && \
   npm install -g --ignore-scripts markdownlint-cli@0.47.0 && \
   apt-get -y install --no-install-recommends --no-install-suggests python3-minimal python3-pip && \
   rm /usr/lib/python3.*/EXTERNALLY-MANAGED && \
-  pip install --no-cache-dir yamllint && \
+  apt-get -y install --no-install-recommends --no-install-suggests yamllint && \
   apt-get -y install --no-install-recommends --no-install-suggests cppcheck && \
   rm -rf /var/lib/apt/lists/*
 
+# Tooling test
+RUN clang-format --version && \
+  markdownlint --version && \
+  yamllint --version && \
+  cppcheck --version
+
 # Code source
 COPY ./src ${WORKDIR}/src
 COPY ./vcpkg.json ${WORKDIR}/vcpkg.json
diff --git a/src/lib/exercises/src/hackerrank/warmup/compare_triplets.c b/src/lib/exercises/src/hackerrank/warmup/compare_triplets.c
index 3cbfb53..0abb5c0 100644
--- a/src/lib/exercises/src/hackerrank/warmup/compare_triplets.c
+++ b/src/lib/exercises/src/hackerrank/warmup/compare_triplets.c
@@ -12,6 +12,9 @@ int *HACKERRANK_WARMUP_compareTriplets(int a_count, const int *a, int b_count,
 
   *result_count = 2;
   int *awards = malloc(sizeof(int) * *result_count);
+  if (awards == NULL) {
+    return NULL;
+  }
 
   awards[0] = 0;
   awards[1] = 0;
diff --git a/src/lib/exercises/src/hackerrank/warmup/mini_max_sum.c b/src/lib/exercises/src/hackerrank/warmup/mini_max_sum.c
index 5e6613c..9eed7a7 100644
--- a/src/lib/exercises/src/hackerrank/warmup/mini_max_sum.c
+++ b/src/lib/exercises/src/hackerrank/warmup/mini_max_sum.c
@@ -27,6 +27,9 @@ char *HACKERRANK_WARMUP_miniMaxSumCalculate(int arr_count, const int *arr) {
 
   const int BUFFER_MAX_SIZE = 100;
   char *buffer = malloc(BUFFER_MAX_SIZE * sizeof(char));
+  if (buffer == NULL) {
+    return NULL;
+  }
 
   snprintf(buffer, BUFFER_MAX_SIZE, "%lld %lld", tsum - tmax, tsum - tmin);
   return buffer;
@@ -34,6 +37,10 @@ char *HACKERRANK_WARMUP_miniMaxSumCalculate(int arr_count, const int *arr) {
 
 void HACKERRANK_WARMUP_miniMaxSum(int arr_count, const int *arr) {
   char *result = HACKERRANK_WARMUP_miniMaxSumCalculate(arr_count, arr);
+  if (result == NULL) {
+    return;
+  }
+
   printf("%s\n", result);
   free(result);
 }
diff --git a/src/lib/exercises/src/hackerrank/warmup/plus_minus.c b/src/lib/exercises/src/hackerrank/warmup/plus_minus.c
index c2f322d..f98d906 100644
--- a/src/lib/exercises/src/hackerrank/warmup/plus_minus.c
+++ b/src/lib/exercises/src/hackerrank/warmup/plus_minus.c
@@ -11,6 +11,9 @@ const int BUFFER_MAX_SIZE = 10;
 
 char *format_result(double number) {
   char *buffer = malloc(BUFFER_MAX_SIZE * sizeof(char));
+  if (buffer == NULL) {
+    return NULL;
+  }
 
   snprintf(buffer, BUFFER_MAX_SIZE, "%0.6lf", number);
   return buffer;
@@ -45,9 +48,16 @@ char **HACKERRANK_WARMUP_plusMinusCalculate(int arr_count, const int *arr) {
 
   int n = 3; // Número de strings (puede ser arbitrario)
   char **answer = malloc(n * sizeof(char *)); // Array de punteros
+  if (answer == NULL) {
+    return NULL;
+  }
 
   for (i = 0; i < n; i++) {
     char *formatted = format_result(results[i]);
+    if (formatted == NULL) {
+      HACKERRANK_WARMUP_freePlusMinus(answer, i);
+      return NULL;
+    }
     answer[i] = formatted;
   }
 
@@ -63,6 +73,9 @@ void HACKERRANK_WARMUP_freePlusMinus(char **plusMinusAnswer, int n) {
 
 void HACKERRANK_WARMUP_plusMinus(int arr_count, const int *arr) {
   char **output = HACKERRANK_WARMUP_plusMinusCalculate(arr_count, arr);
+  if (output == NULL) {
+    return;
+  }
 
   for (int i = 0; i < HACKERRANK_WARMUP_PLUSMINUS_LIMIT_ANSWERS; i++) {
     printf("%s", output[i]);
diff --git a/src/lib/exercises/src/hackerrank/warmup/staircase.c b/src/lib/exercises/src/hackerrank/warmup/staircase.c
index 4473eec..12a305b 100644
--- a/src/lib/exercises/src/hackerrank/warmup/staircase.c
+++ b/src/lib/exercises/src/hackerrank/warmup/staircase.c
@@ -10,9 +10,16 @@
 char **HACKERRANK_WARMUP_staircaseCalculate(int n) {
 
   char **answer = malloc(n * sizeof(char *)); // Array of char pointers
+  if (answer == NULL) {
+    return NULL;
+  }
 
   for (int i = 0; i < n; i++) {
     char *line = malloc((n + 1) * sizeof(char)); // Array of char values
+    if (line == NULL) {
+      HACKERRANK_WARMUP_freeStaircase(answer, i);
+      return NULL;
+    }
 
     for (int j = 0; j < n; j++) {
       if (j < n - i - 1) {
@@ -38,6 +45,9 @@ void HACKERRANK_WARMUP_freeStaircase(char **staircase, int n) {
 
 void HACKERRANK_WARMUP_staircase(int n) {
   char **output = HACKERRANK_WARMUP_staircaseCalculate(n);
+  if (output == NULL) {
+    return;
+  }
 
   for (int i = 0; i < n; i++) {
     printf("%s\n", output[i]);
diff --git a/src/lib/exercises/src/hackerrank/warmup/time_conversion.c b/src/lib/exercises/src/hackerrank/warmup/time_conversion.c
index 638b71c..7b4de53 100644
--- a/src/lib/exercises/src/hackerrank/warmup/time_conversion.c
+++ b/src/lib/exercises/src/hackerrank/warmup/time_conversion.c
@@ -54,6 +54,10 @@ char *HACKERRANK_WARMUP_timeConversion(const char *s) {
   char *conversion =
       malloc((HACKERRANK_WARMUP_SHORT_TIME_FORMAT_SIZE + 1) * sizeof(char));
 
+  if (conversion == NULL) {
+    return NULL;
+  }
+
   for (int i = 0; i < HACKERRANK_WARMUP_SHORT_TIME_FORMAT_SIZE; i++) {
     conversion[i] = s[i];
   }