diff --git a/.config/nvim/lua/rc/plugins/init.lua b/.config/nvim/lua/rc/plugins/init.lua
index 77abc54..22fe5b7 100644
--- a/.config/nvim/lua/rc/plugins/init.lua
+++ b/.config/nvim/lua/rc/plugins/init.lua
@@ -1,10 +1,18 @@
 local lazypath = vim.fn.stdpath("data") .. "/lazy/lazy.nvim"
 if not (vim.uv or vim.loop).fs_stat(lazypath) then
   local lazyrepo = "https://github.com/folke/lazy.nvim.git"
-  local out = vim.fn.system({ "git", "clone", "--filter=blob:none", "--branch=stable", lazyrepo, lazypath })
+  -- Supply-chain hardening: pin to a specific commit instead of --branch=stable
+  -- Commit from lazy-lock.json; update both when upgrading lazy.nvim
+  local out = vim.fn.system({ "git", "clone", "--filter=blob:none", "--single-branch", lazyrepo, lazypath })
+  if vim.v.shell_error == 0 then
+    local co_out = vim.fn.system({ "git", "-C", lazypath, "checkout", "306a05526ada86a7b30af95c5cc81ffba93fef97" })
+    if vim.v.shell_error ~= 0 then
+      out = co_out
+    end
+  end
   if vim.v.shell_error ~= 0 then
     vim.api.nvim_echo({
-      { "Failed to clone lazy.nvim:\n", "ErrorMsg" },
+      { "Failed to install lazy.nvim:\n", "ErrorMsg" },
       { out, "WarningMsg" },
       { "\nPress any key to exit..." },
     }, true, {})
diff --git a/.config/zsh/rc/pluginlist.zsh b/.config/zsh/rc/pluginlist.zsh
index cd939b9..7bef88d 100644
--- a/.config/zsh/rc/pluginlist.zsh
+++ b/.config/zsh/rc/pluginlist.zsh
@@ -7,7 +7,9 @@ fi
 if ! test -d "$ZPLG_HOME"; then
   mkdir -p "$ZPLG_HOME"
   chmod g-rwX "$ZPLG_HOME"
-  git clone --depth 10 https://github.com/zdharma-continuum/zinit.git ${ZPLG_HOME}/bin
+  # Supply-chain hardening: pin zinit to commit corresponding to v3.14.0
+  git clone --depth 1 https://github.com/zdharma-continuum/zinit.git "${ZPLG_HOME}/bin"
+  (cd "${ZPLG_HOME}/bin" && git checkout --detach 412ff3b6d9c0cd9ceb4b4f17aea39dda9e1abad5)
 fi
 typeset -gAH ZPLGM
 ZPLGM[HOME_DIR]="${ZPLG_HOME}"
@@ -23,16 +25,20 @@ autoload -Uz _zinit
 #--------------------------------#
 # history
 #--------------------------------#
+# Supply-chain hardening: pin each plugin to a specific commit via ver"<hash>"
 zinit wait'1' lucid \
   if"(( ${ZSH_VERSION%%.*} > 4.4))" \
+  ver"14c8d2e0ffaee98f2df9850b19944f32546fdea5" \
   light-mode for @zsh-users/zsh-history-substring-search
 
 zinit wait'1' lucid \
   if"(( ${ZSH_VERSION%%.*} > 4.4))" \
+  ver"9bc52fed2900460fc4bef0a77c9382d6175eb63a" \
   light-mode for @zdharma/history-search-multi-word
 
 zinit wait'1' lucid \
   if"(( ${ZSH_VERSION%%.*} > 4.4))" \
+  ver"598675303044df8e9d04722f3adff4f63a238922" \
   light-mode for @mollifier/anyframe
   autoload -Uz chpwd_recent_dirs cdr add-zsh-hook
   add-zsh-hook chpwd chpwd_recent_dirs
@@ -54,10 +60,12 @@ zinit wait'1' lucid \
 #--------------------------------#
 zinit wait'0' lucid \
   if"(( ${ZSH_VERSION%%.*} > 4.4))" \
+  ver"85919cd1ffa7d2d5412f6d3fe437ebdbeeec4fc5" \
   light-mode for @zsh-users/zsh-autosuggestions
 
 zinit wait'1' lucid \
   if"(( ${ZSH_VERSION%%.*} > 4.4))" \
+  ver"adad765241061b9b63485991f268b2771524ed42" \
   light-mode for @zsh-users/zsh-completions
 
 #--------------------------------#
@@ -65,6 +73,7 @@ zinit wait'1' lucid \
 # --------------------------------#
 zinit wait'1' lucid \
   if"(( ${ZSH_VERSION%%.*} > 4.4))" \
+  ver"1d85c692615a25fe2293bdd44b34c217d5d2bf04" \
   light-mode for @zsh-users/zsh-syntax-highlighting
 
 #--------------------------------#
diff --git a/.github/workflows/gitguardian.yml b/.github/workflows/gitguardian.yml
index dda6da5..a6b6d49 100644
--- a/.github/workflows/gitguardian.yml
+++ b/.github/workflows/gitguardian.yml
@@ -8,11 +8,12 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v4
+        # Supply-chain hardening: pin actions to full commit SHA
+        uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
         with:
           fetch-depth: 0 # fetch all history so multiple commits can be scanned
       - name: GitGuardian scan
-        uses: GitGuardian/ggshield-action@v1
+        uses: GitGuardian/ggshield-action@8fc5e12b83a2f2a9f71b88bb12d0d5cf152b1689 # v1.49.0
         env:
           GITHUB_PUSH_BEFORE_SHA: ${{ github.event.before }}
           GITHUB_PUSH_BASE_SHA: ${{ github.event.base }}
diff --git a/.github/workflows/lua-lint.yml b/.github/workflows/lua-lint.yml
index 506db67..fb1f247 100644
--- a/.github/workflows/lua-lint.yml
+++ b/.github/workflows/lua-lint.yml
@@ -14,11 +14,12 @@ jobs:
     env:
       CI: true
     steps:
-      - uses: actions/checkout@v4
+      # Supply-chain hardening: pin actions to full commit SHA
+      - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
 
       - name: Cache lint tools
         id: cache-tools
-        uses: actions/cache@v4
+        uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0
         with:
           path: ~/.local/bin
           key: lint-tools-stylua-0.20.0-selene-0.27.1
@@ -27,11 +28,18 @@ jobs:
         if: steps.cache-tools.outputs.cache-hit != 'true'
         run: |
           mkdir -p ~/.local/bin
+
+          # Supply-chain hardening: verify checksums of downloaded binaries
+          STYLUA_SHA256="28eddb9257bf85b20b1c337e536b7a3d16ba308863f067d447c1f4d24c6dec64"
           curl -LO https://github.com/JohnnyMorganz/StyLua/releases/download/v0.20.0/stylua-linux-x86_64.zip
+          echo "${STYLUA_SHA256}  stylua-linux-x86_64.zip" | sha256sum -c -
           unzip stylua-linux-x86_64.zip -d ~/.local/bin
           chmod +x ~/.local/bin/stylua
           rm stylua-linux-x86_64.zip
+
+          SELENE_SHA256="22dabfe070c6d10cbb0b8ae56a82abfa131fbb902bff03d9924f0f73fd3d3318"
           curl -LO https://github.com/Kampfkarren/selene/releases/download/0.27.1/selene-0.27.1-linux.zip
+          echo "${SELENE_SHA256}  selene-0.27.1-linux.zip" | sha256sum -c -
           unzip selene-0.27.1-linux.zip -d ~/.local/bin
           chmod +x ~/.local/bin/selene
           rm selene-0.27.1-linux.zip
diff --git a/.github/workflows/neovim-health.yml b/.github/workflows/neovim-health.yml
index cf6f67a..ac7e3b9 100644
--- a/.github/workflows/neovim-health.yml
+++ b/.github/workflows/neovim-health.yml
@@ -17,16 +17,17 @@ jobs:
     env:
       CI: true
     steps:
-      - uses: actions/checkout@v4
+      # Supply-chain hardening: pin actions to full commit SHA
+      - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4.3.1
 
       - name: Install Neovim
-        uses: rhysd/action-setup-vim@v1
+        uses: rhysd/action-setup-vim@febef33995d6649302e9d88dda81e071b68f16a7 # v1.6.1
         with:
           neovim: true
           version: ${{ matrix.channel }}
 
       - name: Cache lazy.nvim directories
-        uses: actions/cache@v4
+        uses: actions/cache@0057852bfaa89a56745cba8c7296529d2fc39830 # v4.3.0
         with:
           path: |
             ${{ github.workspace }}/.local/share/nvim
diff --git a/install_scripts/lib/dotinstaller/install-brewfile.sh b/install_scripts/lib/dotinstaller/install-brewfile.sh
index 2bef9e2..60ce9b5 100755
--- a/install_scripts/lib/dotinstaller/install-brewfile.sh
+++ b/install_scripts/lib/dotinstaller/install-brewfile.sh
@@ -6,6 +6,14 @@ function is_brewfile_installed() {
   command -v brew-file >/dev/null 2>&1
 }
 
+_sha256() {
+  if command -v sha256sum >/dev/null 2>&1; then
+    sha256sum "$1" | awk '{print $1}'
+  else
+    shasum -a 256 "$1" | awk '{print $1}'
+  fi
+}
+
 function main() {
   local current_dir
   current_dir=$(dirname "${BASH_SOURCE[0]:-$0}")
@@ -16,11 +24,29 @@ function main() {
   fi
 
   echo "Brewfile is not installed. Installing Brewfile..."
-  # Brewfileのインストール
-  curl -o install.sh -fsSL https://raw.github.com/rcmdnk/homebrew-file/install/install.sh
-  chmod 755 ./install.sh
-   ./install.sh
-  rm -f install.sh
+
+  # Supply-chain hardening: pin to a specific commit on the install branch
+  local brewfile_commit="723acc6f3e0db4677c03bb87c4ea33157d549e26"
+  local expected_sha256="464d39329e5e13939861dab96fbaf64e30513ef4a0666b7edaf7784079ba6fa7"
+  local install_script
+  install_script=$(mktemp "${TMPDIR:-/tmp}/brewfile-install.XXXXXX")
+  trap 'rm -f "$install_script"' EXIT
+
+  curl -fsSL -o "$install_script" \
+    "https://raw.githubusercontent.com/rcmdnk/homebrew-file/${brewfile_commit}/install.sh"
+
+  # Verify SHA256 checksum before execution (update hash when bumping commit)
+  local actual_sha256
+  actual_sha256=$(_sha256 "$install_script")
+  if [ "$actual_sha256" != "$expected_sha256" ]; then
+    echo "🚨ERROR🚨 homebrew-file install script checksum mismatch!"
+    echo "  expected: ${expected_sha256}"
+    echo "  actual:   ${actual_sha256}"
+    exit 1
+  fi
+
+  chmod 755 "$install_script"
+  "$install_script"
 
   # インストールが成功したか再確認
   if is_brewfile_installed; then
diff --git a/install_scripts/lib/dotinstaller/install-fonts.sh b/install_scripts/lib/dotinstaller/install-fonts.sh
index a15fe90..618f123 100755
--- a/install_scripts/lib/dotinstaller/install-fonts.sh
+++ b/install_scripts/lib/dotinstaller/install-fonts.sh
@@ -2,25 +2,58 @@
 
 set -ue
 
+# Supply-chain hardening: pin font releases and verify checksums
+_sha256() {
+  if command -v sha256sum >/dev/null 2>&1; then
+    sha256sum "$1" | awk '{print $1}'
+  else
+    shasum -a 256 "$1" | awk '{print $1}'
+  fi
+}
+
+verify_checksum() {
+  local file="$1" expected="$2"
+  local actual
+  actual=$(_sha256 "$file")
+  if [ "$actual" != "$expected" ]; then
+    echo "🚨ERROR🚨 Checksum mismatch for ${file}!"
+    echo "  expected: ${expected}"
+    echo "  actual:   ${actual}"
+    rm -f "$file"
+    exit 1
+  fi
+}
+
+FONT_TMPDIR=$(mktemp -d "${TMPDIR:-/tmp}/dotinstaller-fonts.XXXXXX")
+trap 'rm -rf "$FONT_TMPDIR"' EXIT
+
 mkdir -p ~/.local/share/fonts
 
-# udev gothic
+# udev gothic — pinned to v2.2.0
+UDEV_GOTHIC_VERSION="v2.2.0"
+UDEV_GOTHIC_SHA256="c104c171f6ed8922ca52d74cd915a271e427f1e884e51431aae71d99e8b3b47b"
 mkdir -p ~/.local/share/fonts/UDEVGothic
-UDEV_GOTHIC_RELEASES_URL="https://api.github.com/repos/yuru7/udev-gothic/releases"
-curl -sfL "${UDEV_GOTHIC_RELEASES_URL}" | jq -r '.[0].assets | .[].browser_download_url' | xargs -I{} curl -fL -o /tmp/UDEVGothic.zip "{}"
-(cd /tmp && unzip -j -o UDEVGothic.zip -d ~/.local/share/fonts/UDEVGothic)
+curl -fL -o "$FONT_TMPDIR/UDEVGothic.zip" \
+  "https://github.com/yuru7/udev-gothic/releases/download/${UDEV_GOTHIC_VERSION}/UDEVGothic_${UDEV_GOTHIC_VERSION}.zip"
+verify_checksum "$FONT_TMPDIR/UDEVGothic.zip" "$UDEV_GOTHIC_SHA256"
+(cd "$FONT_TMPDIR" && unzip -j -o UDEVGothic.zip -d ~/.local/share/fonts/UDEVGothic)
 
-# Hack Nerd Font
+# Hack Nerd Font — pinned to v3.4.0
+HACK_NERD_FONT_VERSION="v3.4.0"
+HACK_NERD_FONT_SHA256="8ca33a60c791392d872b80d26c42f2bfa914a480f9eb2d7516d9f84373c36897"
 mkdir -p ~/.local/share/fonts/HackNerdFont
-HACK_NERD_FONT_RELEASES_URL="https://api.github.com/repos/ryanoasis/nerd-fonts/releases"
-curl -sfL "${HACK_NERD_FONT_RELEASES_URL}" | jq -r '.[0].assets | .[].browser_download_url' | grep Hack.zip | xargs -I{} curl -fL -o /tmp/HackNerdFont.zip "{}"
-(cd /tmp && unzip -j -o HackNerdFont.zip -d ~/.local/share/fonts/HackNerdFont)
+curl -fL -o "$FONT_TMPDIR/HackNerdFont.zip" \
+  "https://github.com/ryanoasis/nerd-fonts/releases/download/${HACK_NERD_FONT_VERSION}/Hack.zip"
+verify_checksum "$FONT_TMPDIR/HackNerdFont.zip" "$HACK_NERD_FONT_SHA256"
+(cd "$FONT_TMPDIR" && unzip -j -o HackNerdFont.zip -d ~/.local/share/fonts/HackNerdFont)
 
-# Fira Code
+# Fira Code — pinned to 6.2
+FIRA_CODE_VERSION="6.2"
+FIRA_CODE_SHA256="0949915ba8eb24d89fd93d10a7ff623f42830d7c5ffc3ecbf960e4ecad3e3e79"
 mkdir -p ~/.local/share/fonts/FiraCode
-FIRA_CODE_RELEASES_URL="https://api.github.com/repos/tonsky/FiraCode/releases"
-LATEST_ZIP_URL=$(curl -sfL "${FIRA_CODE_RELEASES_URL}" | jq -r '.[0].assets[] | select(.name | contains(".zip")) | .browser_download_url')
-curl -fL -o /tmp/FiraCode.zip "${LATEST_ZIP_URL}"
-(cd /tmp && unzip -j -o FiraCode.zip -d ~/.local/share/fonts/FiraCode)
+curl -fL -o "$FONT_TMPDIR/FiraCode.zip" \
+  "https://github.com/tonsky/FiraCode/releases/download/${FIRA_CODE_VERSION}/Fira_Code_v${FIRA_CODE_VERSION}.zip"
+verify_checksum "$FONT_TMPDIR/FiraCode.zip" "$FIRA_CODE_SHA256"
+(cd "$FONT_TMPDIR" && unzip -j -o FiraCode.zip -d ~/.local/share/fonts/FiraCode)
 
 fc-cache -vf
diff --git a/install_scripts/lib/dotinstaller/install-homebrew.sh b/install_scripts/lib/dotinstaller/install-homebrew.sh
index b2bd0fc..c4b75f0 100755
--- a/install_scripts/lib/dotinstaller/install-homebrew.sh
+++ b/install_scripts/lib/dotinstaller/install-homebrew.sh
@@ -6,6 +6,14 @@ function is_homebrew_installed() {
   command -v brew >/dev/null 2>&1
 }
 
+_sha256() {
+  if command -v sha256sum >/dev/null 2>&1; then
+    sha256sum "$1" | awk '{print $1}'
+  else
+    shasum -a 256 "$1" | awk '{print $1}'
+  fi
+}
+
 function main() {
   local current_dir
   current_dir=$(dirname "${BASH_SOURCE[0]:-$0}")
@@ -16,8 +24,28 @@ function main() {
   fi
 
   echo "Homebrew is not installed. Installing Homebrew..."
-  # Homebrewのインストール
-  /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
+
+  # Supply-chain hardening: pin to a specific commit instead of HEAD
+  local brew_commit="6d5e2670d07961e7985d2079a2f0a484420f3c38"
+  local expected_sha256="dfd5145fe2aa5956a600e35848765273f5798ce6def01bd08ecec088a1268d91"
+  local brew_script
+  brew_script=$(mktemp -t brew_install.XXXXXX)
+  trap 'rm -f "$brew_script"' EXIT
+
+  curl -fsSL "https://raw.githubusercontent.com/Homebrew/install/${brew_commit}/install.sh" \
+    -o "$brew_script"
+
+  # Verify SHA256 checksum before execution (update hash when bumping brew_commit)
+  local actual_sha256
+  actual_sha256=$(_sha256 "$brew_script")
+  if [ "$actual_sha256" != "$expected_sha256" ]; then
+    echo "🚨ERROR🚨 Homebrew install script checksum mismatch!"
+    echo "  expected: ${expected_sha256}"
+    echo "  actual:   ${actual_sha256}"
+    exit 1
+  fi
+
+  /bin/bash "$brew_script"
 
   # インストールが成功したか再確認
   if is_homebrew_installed; then
diff --git a/install_scripts/lib/dotinstaller/install-skk.sh b/install_scripts/lib/dotinstaller/install-skk.sh
index 586ecc2..d5515b2 100755
--- a/install_scripts/lib/dotinstaller/install-skk.sh
+++ b/install_scripts/lib/dotinstaller/install-skk.sh
@@ -1,8 +1,9 @@
 #!/bin/bash
 
 # install yaskkserv2
-if ! command -v yaskkserv2 >/dev/temp/null; then
-  cargo install --git https://github.com/wachikun/yaskkserv2 --locked --bins
+# Supply-chain hardening: pin to a specific release tag
+if ! command -v yaskkserv2 >/dev/null 2>&1; then
+  cargo install --git https://github.com/wachikun/yaskkserv2 --tag 0.1.7 --locked --bins
 fi
 
 # setup launch agent