chore(changelog): update changelog for v0.5.1

chore(version): bump to 0.5.1
chore(changelog): update unreleased changelog
2025-06-15 14:52:14 +00:00 · 2025-06-15 16:52:05 +02:00 · 2025-06-15 14:51:30 +00:00 · 2025-06-15 16:51:21 +02:00 · 2025-06-15 16:51:21 +02:00 · 2025-06-15 16:51:21 +02:00
30 changed files with 1214 additions and 345 deletions
--- a/.gitea/default_merge_message/MERGE_TEMPLATE.md
+++ b/.gitea/default_merge_message/MERGE_TEMPLATE.md
@@ -0,0 +1,5 @@
+chore(pr): ${PullRequestTitle} ${PullRequestReference}
+
+${PullRequestDescription}
+
+Merged from ${HeadBranch} into ${BaseBranch}
--- a/.gitea/workflows/ci.yml
+++ b/.gitea/workflows/ci.yml
@@ -0,0 +1,54 @@
+name: CI
+
+on:
+  workflow_dispatch:
+  push:
+    branches:
+      - main
+  pull_request:
+    types:
+      - opened
+      - synchronize
+      - reopened
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+      - uses: denoland/setup-deno@v1
+        with:
+          deno-version: v2.x
+
+      - name: Format
+        id: format
+        continue-on-error: true
+        run: deno task fmt
+
+      - name: Lint
+        id: lint
+        continue-on-error: true
+        run: deno task lint
+
+      - name: Test
+        id: test
+        continue-on-error: true
+        run: deno task test
+
+      - name: Compile
+        id: compile
+        continue-on-error: true
+        run: |
+          deno task build:amd64
+          deno task build:arm64
+
+      - name: Fail if any step failed
+        if: |
+          steps.format.outcome != 'success' ||
+          steps.lint.outcome != 'success' ||
+          steps.test.outcome != 'success' ||
+          steps.compile.outcome != 'success'
+        run: |
+          echo "::error::One or more steps failed"
+          exit 1
--- a/.gitea/workflows/release.yml
+++ b/.gitea/workflows/release.yml
@@ -4,219 +4,16 @@ on:
  push:
    branches:
      - main
-      - '**'
+      - "**"

 jobs:
-  detect-version-change:
-    runs-on: ubuntu-latest
-    outputs:
-      version_changed: ${{ steps.set.outputs.version_changed }}
-    steps:
-      - uses: actions/checkout@v4
-        with:
-          fetch-depth: 0
-
-      - name: Check if VERSION file changed
-        if: github.ref == 'refs/heads/main'
-        run: |
-          echo "🔍 Vergleich mit github.event.before:"
-          echo "Before: ${{ github.event.before }}"
-          echo "After:  ${{ github.sha }}"
-
-          echo "📄 Changed files between before and after:"
-          git diff --name-only ${{ github.event.before }} ${{ github.sha }} || echo "(diff failed)"
-
-          if git diff --name-only ${{ github.event.before }} ${{ github.sha }} | grep -q '^VERSION$'; then
-            echo "✅ VERSION file was changed"
-            echo "VERSION_CHANGED=true" >> $GITHUB_ENV
-          else
-            echo "ℹ️ VERSION file not changed"
-            echo "VERSION_CHANGED=false" >> $GITHUB_ENV
-          fi
-
-      - name: Set output (always)
-        id: set
-        run: |
-          echo "version_changed=${VERSION_CHANGED:-false}" >> $GITHUB_OUTPUT
-
-  changelog-only:
-    needs: detect-version-change
-    if: github.ref != 'refs/heads/main' || needs.detect-version-change.outputs.version_changed == 'false'
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-        with:
-          fetch-depth: 0
-
-      - name: Set Git Author
-        run: |
-          git config user.name "$CI_COMMIT_AUTHOR_NAME"
-          git config user.email "$CI_COMMIT_AUTHOR_EMAIL"
-
-      - name: Read CLIFF_VERSION from cliff.toml
-        id: cliff_version
-        run: |
-          echo "version=$(awk -F '=' '/^# CLIFF_VERSION=/ { gsub(/[" ]/, "", $2); print $2 }' cliff.toml)" >> $GITHUB_OUTPUT
-
-      - name: Restore git-cliff cache
-        id: restore-cliff
-        uses: https://git.0xmax42.io/actions/cache@v1
-        with:
-          key: cargo-cliff-${{ steps.cliff_version.outputs.version }}
-          paths: |
-            /root/.cargo/bin
-
-      - name: Install git-cliff
-        if: steps.restore-cliff.outputs.cache-hit != 'true'
-        run: |
-          cargo install git-cliff --version "${{ steps.cliff_version.outputs.version }}" --features gitea
-
-      - name: Generate unreleased changelog (if file exists or on main)
-        run: |
-          if [[ -f CHANGELOG.md || "${GITHUB_REF##refs/heads/}" == "main" ]]; then
-            echo "Generating CHANGELOG.md..."
-            git-cliff -c cliff.toml -o CHANGELOG.md
-          else
-            echo "CHANGELOG.md does not exist and this is not 'main'. Skipping generation."
-          fi
-
-      - name: Commit updated CHANGELOG
-        run: |
-          git add CHANGELOG.md
-          if git diff --cached --quiet; then
-            echo "No changes to commit"
-          else
-            git commit -m "chore(changelog): update unreleased changelog"
-            git push origin "${GITHUB_REF##refs/heads/}"
-          fi
-
  release:
-    needs: detect-version-change
-    if: needs.detect-version-change.outputs.version_changed == 'true' && github.ref == 'refs/heads/main'
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
-
-      - name: Set Git Author
-        run: |
-          git config user.name "$CI_COMMIT_AUTHOR_NAME"
-          git config user.email "$CI_COMMIT_AUTHOR_EMAIL"
-
-      - name: Read VERSION
-        id: version
-        run: echo "value=$(cat VERSION)" >> $GITHUB_OUTPUT
-
-      - name: Read CLIFF_VERSION from cliff.toml
-        id: cliff_version
-        run: |
-          echo "version=$(awk -F '=' '/^# CLIFF_VERSION=/ { gsub(/[" ]/, "", $2); print $2 }' cliff.toml)" >> $GITHUB_OUTPUT
-
-      - name: Restore git-cliff cache
-        id: restore-cliff
-        uses: https://git.0xmax42.io/actions/cache@v1
+      - name: Release
+        uses: https://git.0xmax42.io/actions/auto-changelog-release-action@v0
        with:
-          key: cargo-cliff-${{ steps.cliff_version.outputs.version }}
-          paths: |
-            /root/.cargo/bin
-
-      - name: Install git-cliff
-        if: steps.restore-cliff.outputs.cache-hit != 'true'
-        run: |
-          cargo install git-cliff --version "${{ steps.cliff_version.outputs.version }}" --features gitea
-      
-      - name: Generate changelog for release and tag
-        id: generate-changelog
-        run: |
-          VERSION=${{ steps.version.outputs.value }}
-          git-cliff -c cliff.toml -t "v$VERSION" -o CHANGELOG.md
-
-          BODY=$(mktemp)
-          ESCAPED_VERSION=$(echo "$VERSION" | sed 's/\./\\./g')
-
-          awk -v ver="$ESCAPED_VERSION" '
-            $0 ~ "^## \\[" ver "\\]" {
-              print_flag=1
-              line = $0
-              sub(/^## /, "", line)
-              sub(/\\s*\\(.*\\)/, "", line)  # entfernt z. B. "(...)" oder "(*)"
-              print line
-              next
-            }
-            $0 ~ "^## \\[" && $0 !~ "^## \\[" ver "\\]" {
-              print_flag=0
-            }
-            print_flag
-          ' CHANGELOG.md > "$BODY"
-
-          echo "changelog_body_path=$BODY" >> $GITHUB_OUTPUT
-
-
-      - name: Commit updated CHANGELOG
-        run: |
-          git add CHANGELOG.md
-          if git diff --cached --quiet; then
-            echo "No changes to commit"
-          else
-            git commit -m "chore(changelog): update changelog for v${{ steps.version.outputs.value }}"
-            git push origin main
-          fi
-
-      - name: Create Git tag (if not exists)
-        run: |
-          VERSION=${{ steps.version.outputs.value }}
-          if git rev-parse "v$VERSION" >/dev/null 2>&1; then
-            echo "Tag v$VERSION already exists, skipping tag creation."
-          else
-            git tag -a "v$VERSION" -F "${{ steps.generate-changelog.outputs.changelog_body_path }}" --cleanup=verbatim
-            git push origin "v$VERSION"
-          fi
-
-      - name: Create Gitea release
-        env: 
-          RELEASE_PUBLISH_TOKEN: ${{ secrets.RELEASE_PUBLISH_TOKEN }}
-        run: |
-          VERSION=${{ steps.version.outputs.value }}
-          BODY_FILE="${{ steps.generate-changelog.outputs.changelog_body_path }}"
-
-          OWNER=$(echo "$GITHUB_REPOSITORY" | cut -d/ -f1)
-          REPO=$(echo "$GITHUB_REPOSITORY" | cut -d/ -f2)
-
-          # Token-Auswahl
-          TOKEN="${RELEASE_PUBLISH_TOKEN:-$ACTIONS_RUNTIME_TOKEN}"
-
-          if [[ -z "${RELEASE_PUBLISH_TOKEN:-}" ]]; then
-            echo "::warning title=Limited Release Propagation::"
-            echo "RELEASE_PUBLISH_TOKEN is not set. Using ACTIONS_RUNTIME_TOKEN instead."
-            echo "⚠️  Release events may not trigger other workflows if created with the runtime token."
-            echo
-          fi
-
-          # Prüfe, ob der Release schon existiert
-          if curl -sf "$GITHUB_API_URL/repos/$OWNER/$REPO/releases/tags/v$VERSION" \
-            -H "Authorization: token $TOKEN" > /dev/null; then
-            echo "🔁 Release for tag v$VERSION already exists, skipping."
-            exit 0
-          fi
-
-          echo "🚀 Creating Gitea release for v$VERSION"
-
-          # Release-Beschreibung vorbereiten
-          RELEASE_BODY=$(tail -n +2 "$BODY_FILE" | jq -Rs .)
-
-          curl -X POST "$GITHUB_API_URL/repos/$OWNER/$REPO/releases" \
-            -H "Authorization: token $TOKEN" \
-            -H "Content-Type: application/json" \
-            -d @- <<EOF
-          {
-            "tag_name": "v$VERSION",
-            "target_commitish": "main",
-            "name": "Release v$VERSION",
-            "body": $RELEASE_BODY,
-            "draft": false,
-            "prerelease": false
-          }
-          EOF
-
-          echo "✅ Release for tag $VERSION created successfully."
+          token: ${{ secrets.RELEASE_PUBLISH_TOKEN }}
--- a/.gitea/workflows/sync-github.yml
+++ b/.gitea/workflows/sync-github.yml
@@ -1,28 +0,0 @@
-name: Sync Release to GitHub
-
-on:
-  workflow_dispatch:
-    inputs:
-      tag:
-        description: "Release tag to synchronize"
-        required: false
-        type: string
-  release:
-    types: [published, edited]
-
-jobs:
-  sync-github:
-    runs-on: ubuntu-22.04
-
-    steps:
-      - name: Run Releases Sync Action
-        uses: https://git.0xmax42.io/actions/releases-sync@main
-        with:
-          gitea_token: ${{ secrets.RELEASE_PUBLISH_TOKEN }}
-          gitea_url: https://git.0xmax42.io
-          gitea_owner: maxp
-          gitea_repo: systemd-timer
-          tag_name: ${{ inputs.tag || github.event.release.tag_name }}
-          github_token: ${{ secrets.SYNC_GITHUB_TOKEN }}
-          github_owner: 0xmax42
-          github_repo: systemd-timer
--- a/.gitea/workflows/upload-assets.yml
+++ b/.gitea/workflows/upload-assets.yml
@@ -42,3 +42,31 @@ jobs:

      - name: Upload SHA256 for ${{ matrix.target }}-${{ matrix.arch }}
        run: .gitea/scripts/upload-asset.sh ./dist/systemd-timer-${{ matrix.target }}-${{ matrix.arch }}.sha256 systemd-timer-${{ matrix.target }}-${{ matrix.arch }}.sha256
+
+      - name: Create zstd compressed archive
+        run: |
+          FILE="./dist/systemd-timer-${{ matrix.target }}-${{ matrix.arch }}"
+          zstd -q -19 -T0 -f "$FILE" -o "$FILE.zst"
+
+      - name: Generate SHA256 for zstd compressed archive
+        run: |
+          FILE="./dist/systemd-timer-${{ matrix.target }}-${{ matrix.arch }}.zst"
+          sha256sum "$FILE" > "$FILE.sha256"
+
+      - name: Upload zstd compressed archive for ${{ matrix.target }}-${{ matrix.arch }}
+        run: .gitea/scripts/upload-asset.sh ./dist/systemd-timer-${{ matrix.target }}-${{ matrix.arch }}.zst systemd-timer-${{ matrix.target }}-${{ matrix.arch }}.zst
+
+      - name: Upload SHA256 for zstd compressed archive
+        run: .gitea/scripts/upload-asset.sh ./dist/systemd-timer-${{ matrix.target }}-${{ matrix.arch }}.zst.sha256 systemd-timer-${{ matrix.target }}-${{ matrix.arch }}.zst.sha256
+
+      - name: Run Releases Sync Action
+        uses: https://git.0xmax42.io/actions/releases-sync@main
+        with:
+          gitea_token: ${{ secrets.RELEASE_PUBLISH_TOKEN }}
+          gitea_url: https://git.0xmax42.io
+          gitea_owner: maxp
+          gitea_repo: systemd-timer
+          tag_name: ${{ github.event.release.tag_name }}
+          github_token: ${{ secrets.SYNC_GITHUB_TOKEN }}
+          github_owner: 0xmax42
+          github_repo: systemd-timer
--- a/.vscode/settings.json
+++ b/.vscode/settings.json
@@ -10,6 +10,15 @@
    "peacock.color": "#c75c5c",
    "exportall.config.folderListener": [
        "/src/utils",
-        "/src/types"
-    ]
+        "/src/types",
+        "/src/i18n"
+    ],
+    "deno.enable": true,
+    "[json]": {
+        "editor.defaultFormatter": "denoland.vscode-deno"
+    },
+    "[jsonc]": {
+        "editor.defaultFormatter": "denoland.vscode-deno"
+    },
+    "editor.formatOnSave": true
 }
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,102 @@

 All notable changes to this project will be documented in this file.

+## [0.5.1](https://git.0xmax42.io/maxp/systemd-timer/compare/v0.5.0..v0.5.1) - 2025-06-15
+
+### 🚀 Features
+
+- *(install)* Add support for compressed .zst archives - ([3a1ee0c](https://git.0xmax42.io/maxp/systemd-timer/commit/3a1ee0cfd6ddba8734cde09196803e9ccdd14c5f))
+- *(workflows)* Add zstd compression for build artifacts - ([d9183d2](https://git.0xmax42.io/maxp/systemd-timer/commit/d9183d2f04b03cbdaf9e11bf05f7ce66111123e5))
+
+### 📚 Documentation
+
+- *(readme)* Add input validation and multilingual support - ([ce78cf3](https://git.0xmax42.io/maxp/systemd-timer/commit/ce78cf3a9a14028114e0fb6fcc0973d86c2b2227))
+
+### ⚙️ Miscellaneous Tasks
+
+- *(workflows)* Simplify release workflow with auto-changelog - ([05f3b51](https://git.0xmax42.io/maxp/systemd-timer/commit/05f3b519f56d893a0135736d8b722302c7cdd3f6))
+- *(workflows)* Add locked flag to cargo install for git-cliff - ([6efc151](https://git.0xmax42.io/maxp/systemd-timer/commit/6efc1515ed4f4fb8802405529e4a6e04870ec02a))
+
+## [0.5.0](https://git.0xmax42.io/maxp/systemd-timer/compare/v0.4.1..v0.5.0) - 2025-05-30
+
+### 🚀 Features
+
+- *(cli)* Add validation for command options - ([1c07af4](https://git.0xmax42.io/maxp/systemd-timer/commit/1c07af402b35ba4c2abf89ff5816e791994db536))
+- *(validation)* Add CLI validation helpers for input checks - ([3d95706](https://git.0xmax42.io/maxp/systemd-timer/commit/3d95706d683cac8d279dfb718541a17c42fa5d71))
+- *(build)* Add run permissions to compiled binaries - ([ccb04e4](https://git.0xmax42.io/maxp/systemd-timer/commit/ccb04e49820ff8238d7e7ad853aab5db06d5dc8a))
+- *(ci)* Add compile steps to CI workflow - ([531a02a](https://git.0xmax42.io/maxp/systemd-timer/commit/531a02a6e11a769f2e05888d49ea2b4808d974e3))
+- *(vscode)* Add JSONC formatter configuration - ([c7af1fb](https://git.0xmax42.io/maxp/systemd-timer/commit/c7af1fb6caa46c22b84229745067d05bf60b6f64))
+- *(i18n)* Support loading JSONC translation files - ([4ac5dd4](https://git.0xmax42.io/maxp/systemd-timer/commit/4ac5dd4c88324f99cb6827283ad85bb9718abbeb))
+- *(config)* Add @std/jsonc dependency - ([8f1cb3f](https://git.0xmax42.io/maxp/systemd-timer/commit/8f1cb3fad71ead365d93087963ddb6c7202a9b4f))
+
+### 🐛 Bug Fixes
+
+- *(build)* Update included files to use .jsonc format - ([f3f2c61](https://git.0xmax42.io/maxp/systemd-timer/commit/f3f2c61da0785dce4c6b8c7d8ef0ae9abf098172))
+
+### 🎨 Styling
+
+- *(i18n)* Add comments for clarity and rename files - ([5226269](https://git.0xmax42.io/maxp/systemd-timer/commit/5226269ec2a0b76dfa30ac8d614c3789ff3a837b))
+
+### 🧪 Testing
+
+- *(fs)* Update test descriptions and comments to English - ([c4f4614](https://git.0xmax42.io/maxp/systemd-timer/commit/c4f4614a2daee68f9b33b9676106214c65a1a427))
+- *(fs)* Add rollback tests for writeUnitFiles errors - ([6039d23](https://git.0xmax42.io/maxp/systemd-timer/commit/6039d236eb7de449ce22b1d9ea718389a3e2261d))
+
+### ⚙️ Miscellaneous Tasks
+
+- *(lock)* Update dependencies to latest versions - ([28b23cf](https://git.0xmax42.io/maxp/systemd-timer/commit/28b23cf947ecc57eb7fde541b29c68b41e508e7d))
+
+## [0.4.1](https://git.0xmax42.io/maxp/systemd-timer/compare/v0.4.0..v0.4.1) - 2025-05-28
+
+### 🐛 Bug Fixes
+
+- *(tasks)* Add read permissions to build scripts - ([a22c156](https://git.0xmax42.io/maxp/systemd-timer/commit/a22c156dd3d2cf4a24f0eed699f7dfabfae3837a))
+
+## [0.4.0](https://git.0xmax42.io/maxp/systemd-timer/compare/v0.3.1..v0.4.0) - 2025-05-28
+
+### 🚀 Features
+
+- *(vscode)* Enable Deno support and configure JSON formatting - ([c02da70](https://git.0xmax42.io/maxp/systemd-timer/commit/c02da709028e1fbb175d5091fbd9d3ed2940cdcd))
+- *(ci)* Add CI workflow with format, lint, and test steps - ([9ad407e](https://git.0xmax42.io/maxp/systemd-timer/commit/9ad407e531270445d9657402fa3e826a7dabd880))
+- *(tasks)* Add formatting, linting, and CI tasks - ([07730e5](https://git.0xmax42.io/maxp/systemd-timer/commit/07730e576180be3f6a16b0fda6c6554a86844eee))
+- *(tasks)* Include localization files in build commands - ([440130f](https://git.0xmax42.io/maxp/systemd-timer/commit/440130f782b1fc51053164410ead29397b867892))
+- *(i18n)* Add German and English translations for CLI tool - ([bd5ea80](https://git.0xmax42.io/maxp/systemd-timer/commit/bd5ea80aff5092118920ea897af6c3f5f9fb2a3b))
+- *(i18n)* Add i18n module for localization support - ([c9b4c8b](https://git.0xmax42.io/maxp/systemd-timer/commit/c9b4c8bd71029976fe900b40a2297b52200a216b))
+
+### 🚜 Refactor
+
+- *(cli)* Integrate i18n support across commands - ([2a13ee2](https://git.0xmax42.io/maxp/systemd-timer/commit/2a13ee2539d96d161a9ee398629fa79822d856f2))
+
+### 🎨 Styling
+
+- *(i18n)* Add missing newline at EOF in JSON files - ([54d71ba](https://git.0xmax42.io/maxp/systemd-timer/commit/54d71ba3f00ced25313036d9f10f6fb01feba52a))
+
+### 🧪 Testing
+
+- *(i18n)* Add unit tests for localization functions - ([8efbee1](https://git.0xmax42.io/maxp/systemd-timer/commit/8efbee1ba9b4fc564f5a32fcbc101ff256c5555b))
+
+### ⚙️ Miscellaneous Tasks
+
+- *(vscode)* Update folder listener with i18n directory - ([dfa92d8](https://git.0xmax42.io/maxp/systemd-timer/commit/dfa92d80694b5b104c26e131d1ee7c5cf69ad94c))
+
+## [0.3.1](https://git.0xmax42.io/maxp/systemd-timer/compare/v0.2.3..v0.3.1) - 2025-05-28
+
+### 🚀 Features
+
+- *(cli)* Add options for user, home, and working directory - ([113103f](https://git.0xmax42.io/maxp/systemd-timer/commit/113103f368ead3014165cc708f016a04749f59be))
+
+### 📚 Documentation
+
+- *(readme)* Expand CLI option descriptions for clarity - ([fb2a62d](https://git.0xmax42.io/maxp/systemd-timer/commit/fb2a62d984615caa4035fd5c1e8e64d245499e47))
+
+### 🎨 Styling
+
+- *(workflows)* Fix formatting and whitespace issues - ([c4855ed](https://git.0xmax42.io/maxp/systemd-timer/commit/c4855ed3fbc0ada208690f90932710983daef392))
+
+### ⚙️ Miscellaneous Tasks
+
+- *(workflows)* Consolidate release sync into upload workflow - ([0c1d8be](https://git.0xmax42.io/maxp/systemd-timer/commit/0c1d8be79f0cc331db9029beb46384659f465f6e))
+
 ## [0.2.3](https://git.0xmax42.io/maxp/systemd-timer/compare/v0.2.2..v0.2.3) - 2025-05-26

 ### 🚀 Features
--- a/README.DE.md
+++ b/README.DE.md
@@ -12,13 +12,20 @@ Ein einfaches CLI-Tool zum schnellen Erzeugen von systemd `.service` und `.timer
 - Unterstützt `--user` Timer (für `~/.config/systemd/user/`)
 - Optionales Logging (`StandardOutput/StandardError`)
 - Unterstützt:
-  - `--calendar`
-  - `--exec`
-  - `--after`
-  - `--environment`
-  - `--output`
-  - `--dry-run`
- Getestet und typisiert mit Deno + Cliffy
+  - `--calendar`: Zeitplan für den Timer (systemd `OnCalendar`)
+  - `--exec`: Auszuführendes Kommando (`ExecStart`)
+  - `--description`: Beschreibung für die Unit
+  - `--after`: `After=`-Abhängigkeiten in der Service-Unit
+  - `--environment`: Beliebige `Environment=KEY=VALUE` Einträge
+  - `--output`: Zielverzeichnis für die generierten Unit-Dateien
+  - `--run-as`: Setzt `User=` in der Service-Unit (nur systemweite Timer)
+  - `--home`: Setzt `Environment=HOME=…`
+  - `--cwd`: Arbeitsverzeichnis des Prozesses (`WorkingDirectory`)
+  - `--dry-run`: Gibt nur die generierten Inhalte aus, ohne sie zu schreiben
+- Getestet und typisiert mit **Deno** + **Cliffy**
+- Eingaben werden validiert und auf Fehler geprüft;
+  - z.B. muss `--calendar` ein gültiger systemd `OnCalendar` Ausdruck sein
+- Mehrsprachig (Englisch, Deutsch)

 ---

--- a/README.md
+++ b/README.md
@@ -13,14 +13,20 @@ A simple CLI tool for quickly generating systemd `.service` and `.timer` units
 * Supports `--user` timers (for `~/.config/systemd/user/`)
 * Optional logging (`StandardOutput/StandardError`)
 * Supports:
-
-  * `--calendar`
-  * `--exec`
-  * `--after`
-  * `--environment`
-  * `--output`
-  * `--dry-run`
-* Tested and typed with Deno + Cliffy
+  * `--calendar`: Timer schedule (systemd `OnCalendar`)
+  * `--exec`: Command to execute (`ExecStart`)
+  * `--description`: Description for the unit
+  * `--after`: `After=` dependencies in the service unit
+  * `--environment`: Arbitrary `Environment=KEY=VALUE` entries
+  * `--output`: Target directory for the generated unit files
+  * `--run-as`: Sets `User=` in the service unit (only for system-level timers)
+  * `--home`: Sets `Environment=HOME=…`
+  * `--cwd`: Working directory for the process (`WorkingDirectory`)
+  * `--dry-run`: Outputs unit content without writing to disk
+* Tested and fully typed with **Deno** + **Cliffy**
+* Inputs are validated and checked for errors;
+  * e.g., `--calendar` must be a valid systemd `OnCalendar` expression
+* Multilingual (English, German)

 ---

--- a/2
+++ b/2
@@ -1 +1 @@
-0.2.3
+0.5.1
--- a/deno.jsonc
+++ b/deno.jsonc
@@ -2,8 +2,11 @@
    "tasks": {
        "start": "deno run -A src/mod.ts",
        "test": "deno test -A --coverage **/__tests__/*.test.ts",
-        "build:amd64": "deno compile --target x86_64-unknown-linux-gnu --include=VERSION --allow-env --allow-write --output dist/systemd-timer-linux-amd64 src/mod.ts",
-        "build:arm64": "deno compile --target aarch64-unknown-linux-gnu --include=VERSION --allow-env --allow-write --output dist/systemd-timer-linux-arm64 src/mod.ts"
+        "fmt": "deno fmt --check",
+        "lint": "deno lint",
+        "ci": "deno task fmt && deno task lint && deno task test && build:amd64", // For local CI checks
+        "build:amd64": "deno compile --target x86_64-unknown-linux-gnu --include VERSION --include src/i18n/de.jsonc --include src/i18n/en.jsonc --allow-env --allow-write --allow-read --allow-run --output dist/systemd-timer-linux-amd64 src/mod.ts",
+        "build:arm64": "deno compile --target aarch64-unknown-linux-gnu --include VERSION --include src/i18n/de.jsonc --include src/i18n/en.jsonc --allow-env --allow-write --allow-read --allow-run --output dist/systemd-timer-linux-arm64 src/mod.ts"
    },
    "compilerOptions": {},
    "fmt": {
@@ -20,6 +23,7 @@
    },
    "exclude": [],
    "imports": {
-        "@cliffy/command": "jsr:@cliffy/command@1.0.0-rc.7"
+        "@cliffy/command": "jsr:@cliffy/command@1.0.0-rc.7",
+        "@std/jsonc": "jsr:@std/jsonc@^1.0.2"
    }
 }
--- a/deno.lock
+++ b/deno.lock
@@ -6,6 +6,8 @@
    "jsr:@cliffy/internal@1.0.0-rc.7": "1.0.0-rc.7",
    "jsr:@cliffy/table@1.0.0-rc.7": "1.0.0-rc.7",
    "jsr:@std/fmt@~1.0.2": "1.0.7",
+    "jsr:@std/json@^1.0.2": "1.0.2",
+    "jsr:@std/jsonc@^1.0.2": "1.0.2",
    "jsr:@std/text@~1.0.7": "1.0.13"
  },
  "jsr": {
@@ -37,11 +39,24 @@
    "@std/fmt@1.0.7": {
      "integrity": "2a727c043d8df62cd0b819b3fb709b64dd622e42c3b1bb817ea7e6cc606360fb"
    },
+    "@std/json@1.0.2": {
+      "integrity": "d9e5497801c15fb679f55a2c01c7794ad7a5dfda4dd1bebab5e409cb5e0d34d4"
+    },
+    "@std/jsonc@1.0.2": {
+      "integrity": "909605dae3af22bd75b1cbda8d64a32cf1fd2cf6efa3f9e224aba6d22c0f44c7",
+      "dependencies": [
+        "jsr:@std/json"
+      ]
+    },
    "@std/text@1.0.13": {
      "integrity": "2191c90e6e667b0c3b7dea1cd082137580a93b3c136bad597c0212d5fe006eb1"
    }
  },
  "remote": {
+    "https://deno.land/std@0.192.0/fmt/colors.ts": "d67e3cd9f472535241a8e410d33423980bec45047e343577554d3356e1f0ef4e",
+    "https://deno.land/std@0.192.0/testing/_diff.ts": "1a3c044aedf77647d6cac86b798c6417603361b66b54c53331b312caeb447aea",
+    "https://deno.land/std@0.192.0/testing/_format.ts": "a69126e8a469009adf4cf2a50af889aca364c349797e63174884a52ff75cf4c7",
+    "https://deno.land/std@0.192.0/testing/asserts.ts": "e16d98b4d73ffc4ed498d717307a12500ae4f2cbe668f1a215632d19fcffc22f",
    "https://deno.land/std@0.224.0/assert/_constants.ts": "a271e8ef5a573f1df8e822a6eb9d09df064ad66a4390f21b3e31f820a38e0975",
    "https://deno.land/std@0.224.0/assert/assert.ts": "09d30564c09de846855b7b071e62b5974b001bb72a4b797958fe0660e7849834",
    "https://deno.land/std@0.224.0/assert/assert_almost_equals.ts": "9e416114322012c9a21fa68e187637ce2d7df25bcbdbfd957cd639e65d3cf293",
@@ -168,11 +183,13 @@
    "https://deno.land/std@0.224.0/path/windows/relative.ts": "3e1abc7977ee6cc0db2730d1f9cb38be87b0ce4806759d271a70e4997fc638d7",
    "https://deno.land/std@0.224.0/path/windows/resolve.ts": "8dae1dadfed9d46ff46cc337c9525c0c7d959fb400a6308f34595c45bdca1972",
    "https://deno.land/std@0.224.0/path/windows/to_file_url.ts": "40e560ee4854fe5a3d4d12976cef2f4e8914125c81b11f1108e127934ced502e",
-    "https://deno.land/std@0.224.0/path/windows/to_namespaced_path.ts": "4ffa4fb6fae321448d5fe810b3ca741d84df4d7897e61ee29be961a6aac89a4c"
+    "https://deno.land/std@0.224.0/path/windows/to_namespaced_path.ts": "4ffa4fb6fae321448d5fe810b3ca741d84df4d7897e61ee29be961a6aac89a4c",
+    "https://deno.land/std@0.224.0/testing/mock.ts": "a963181c2860b6ba3eb60e08b62c164d33cf5da7cd445893499b2efda20074db"
  },
  "workspace": {
    "dependencies": [
-      "jsr:@cliffy/command@1.0.0-rc.7"
+      "jsr:@cliffy/command@1.0.0-rc.7",
+      "jsr:@std/jsonc@^1.0.2"
    ]
  }
 }
--- a/scripts/install.sh
+++ b/scripts/install.sh
@@ -1,6 +1,6 @@
 #!/usr/bin/env bash

-# Fail-safe bash mode (only if bash is used)
+# Fail-safe bash mode
 if [ -n "$BASH_VERSION" ]; then
  set -euo pipefail
 else
@@ -26,38 +26,72 @@ case "$OS" in
  *) echo "Unsupported OS: $OS" >&2; exit 1 ;;
 esac

-# === Download-URL zusammensetzen ===
-BINARY_FILE="${BINARY_NAME}-${OS}-${ARCH}"
-DOWNLOAD_URL="${REPO_URL}/${BINARY_FILE}"
+# === Datei- und URL-Namen ===
+BASE_NAME="${BINARY_NAME}-${OS}-${ARCH}"
+ZST_NAME="${BASE_NAME}.zst"
+ZST_URL="${REPO_URL}/${ZST_NAME}"
+BIN_URL="${REPO_URL}/${BASE_NAME}"

 echo "📦 Installing ${BINARY_NAME} for ${OS}/${ARCH}..."
-echo "🌐 Downloading from: ${DOWNLOAD_URL}"

-# === Binary herunterladen ===
-TMP_FILE=$(mktemp)
-curl -fsSL "${DOWNLOAD_URL}" -o "${TMP_FILE}"
-chmod +x "${TMP_FILE}"
-
-# === SHA256-Check ===
-TMP_HASH=$(mktemp)
-curl -fsSL "${DOWNLOAD_URL}.sha256" -o "$TMP_HASH"
-EXPECTED_HASH=$(cut -d ' ' -f1 "$TMP_HASH")
-ACTUAL_HASH=$(openssl dgst -sha256 "$TMP_FILE" | awk '{print $2}')
-
-if [ "$EXPECTED_HASH" != "$ACTUAL_HASH" ]; then
-  echo "⚠️ Checksum mismatch!"
-  echo "Expected: $EXPECTED_HASH"
-  echo "Actual:   $ACTUAL_HASH"
-  exit 1
+USE_ZSTD=false
+if command -v zstd >/dev/null; then
+  echo "✅ 'zstd' found – will use compressed .zst archive"
+  USE_ZSTD=true
 fi

-# === Installation ===
+TMP_DIR=$(mktemp -d)
+cleanup() {
+  rm -rf "$TMP_DIR"
+}
+trap cleanup EXIT
+
+if [ "$USE_ZSTD" = true ]; then
+  echo "🌐 Downloading: ${ZST_URL}"
+  curl -fsSL "$ZST_URL" -o "$TMP_DIR/${ZST_NAME}"
+  echo "🌐 Downloading checksum: ${ZST_URL}.sha256"
+  curl -fsSL "$ZST_URL.sha256" -o "$TMP_DIR/zst.sha256"
+
+  EXPECTED_HASH=$(cut -d ' ' -f1 "$TMP_DIR/zst.sha256")
+  ACTUAL_HASH=$(openssl dgst -sha256 "$TMP_DIR/${ZST_NAME}" | awk '{print $2}')
+
+  if [ "$EXPECTED_HASH" != "$ACTUAL_HASH" ]; then
+    echo "⚠️ Checksum mismatch for .zst archive!"
+    echo "Expected: $EXPECTED_HASH"
+    echo "Actual:   $ACTUAL_HASH"
+    exit 1
+  fi
+
+  echo "📥 Decompressing..."
+  zstd -d -q "$TMP_DIR/${ZST_NAME}" -o "$TMP_DIR/${BASE_NAME}"
+  TMP_FILE="$TMP_DIR/${BASE_NAME}"
+
+else
+  echo "🌐 Downloading uncompressed binary: ${BIN_URL}"
+  curl -fsSL "$BIN_URL" -o "$TMP_DIR/${BASE_NAME}"
+  echo "🌐 Downloading checksum: ${BIN_URL}.sha256"
+  curl -fsSL "$BIN_URL.sha256" -o "$TMP_DIR/binary.sha256"
+
+  EXPECTED_HASH=$(cut -d ' ' -f1 "$TMP_DIR/binary.sha256")
+  ACTUAL_HASH=$(openssl dgst -sha256 "$TMP_DIR/${BASE_NAME}" | awk '{print $2}')
+
+  if [ "$EXPECTED_HASH" != "$ACTUAL_HASH" ]; then
+    echo "⚠️ Checksum mismatch!"
+    echo "Expected: $EXPECTED_HASH"
+    echo "Actual:   $ACTUAL_HASH"
+    exit 1
+  fi
+
+  TMP_FILE="$TMP_DIR/${BASE_NAME}"
+fi
+
+chmod +x "$TMP_FILE"
 echo "🚀 Installing to ${INSTALL_PATH}/${BINARY_NAME}"
 if [ -w "$INSTALL_PATH" ]; then
-  install -m 755 "${TMP_FILE}" "${INSTALL_PATH}/${BINARY_NAME}"
+  install -m 755 "$TMP_FILE" "${INSTALL_PATH}/${BINARY_NAME}"
 else
-  sudo install -m 755 "${TMP_FILE}" "${INSTALL_PATH}/${BINARY_NAME}"
+  sudo install -m 755 "$TMP_FILE" "${INSTALL_PATH}/${BINARY_NAME}"
 fi

 echo "✅ Installation complete: $(command -v ${BINARY_NAME})"
-"${BINARY_NAME}" --version || true
+"${BINARY_NAME}" --version || true
--- a/src/cli/create.ts
+++ b/src/cli/create.ts
@@ -1,39 +1,73 @@
 import { Command } from '@cliffy/command';
 import { generateUnitFiles } from '../templates/unit-generator.ts';
 import { TimerOptions } from '../types/options.ts';
+import { t } from '../i18n/mod.ts';
+import {
+    collectAndValidateAfter,
+    collectAndValidateEnv,
+    validateIdentifier,
+    validateNotEmpty,
+    validatePath,
+    validateSystemdCalendar,
+} from '../utils/mod.ts';

-export const createCommand = new Command()
-    .description('Erzeugt eine systemd .service und .timer Unit')
-    .option(
-        '--name <name:string>',
-        'Name der Unit-Dateien (optional, wird sonst aus dem Exec generiert)',
-    )
-    .option(
-        '--exec <cmd:string>',
-        'Kommando, das durch systemd ausgeführt werden soll',
-        { required: true },
-    )
-    .option('--calendar <time:string>', 'OnCalendar-Ausdruck für den Timer', {
-        required: true,
-    })
-    .option('--description <desc:string>', 'Beschreibung des Timers')
-    .option('--user', 'Erstellt die Unit als User-Timer')
-    .option('--output <dir:string>', 'Zielverzeichnis der Unit-Dateien')
-    .option(
-        '--after <target:string>',
-        'Optionales After= für die Service-Unit',
-        { collect: true },
-    )
-    .option(
-        '--environment <env:string>',
-        'Environment-Variablen im Format KEY=VALUE',
-        { collect: true },
-    )
-    .option(
-        '--logfile <file:string>',
-        'Dateipfad für Log-Ausgabe (stdout/stderr)',
-    )
-    .option('--dry-run', 'Gibt die Unit-Dateien nur aus, ohne sie zu schreiben')
-    .action(async (options: TimerOptions) => {
-        await generateUnitFiles(options);
-    });
+export function createCommand() {
+    return new Command()
+        .description(t('cli_create_description'))
+        .option(
+            '--name <name:string>',
+            t('option_name'),
+            { value: (v) => validateIdentifier(v, '--name') },
+        )
+        .option(
+            '--exec <cmd:string>',
+            t('option_exec'),
+            {
+                required: true,
+                value: (v) => validateNotEmpty(v, '--exec'),
+            },
+        )
+        .option('--calendar <time:string>', t('option_calendar'), {
+            required: true,
+            value: validateSystemdCalendar,
+        })
+        .option('--description <desc:string>', t('option_description'))
+        .option('--user', t('option_user'))
+        .option(
+            '--run-as <user:string>',
+            t('option_run_as'),
+            { value: (v) => validateNotEmpty(v, '--run-as') },
+        )
+        .option(
+            '--home <path:string>',
+            t('option_home'),
+            { value: (v) => validatePath(v, true) },
+        )
+        .option(
+            '--cwd <path:string>',
+            t('option_cwd'),
+            { value: (v) => validatePath(v, true) },
+        )
+        .option('--output <dir:string>', t('option_output'), {
+            value: (v) => validatePath(v, false),
+        })
+        .option(
+            '--after <target:string>',
+            t('option_after'),
+            { collect: true, value: collectAndValidateAfter },
+        )
+        .option(
+            '--environment <env:string>',
+            t('option_environment'),
+            { collect: true, value: collectAndValidateEnv },
+        )
+        .option(
+            '--logfile <file:string>',
+            t('option_logfile'),
+            { value: (v) => validatePath(v, false) },
+        )
+        .option('--dry-run', t('option_dry_run'))
+        .action(async (options: TimerOptions) => {
+            await generateUnitFiles(options);
+        });
+}
--- a/src/cli/main.ts
+++ b/src/cli/main.ts
@@ -1,10 +1,12 @@
 import { Command } from '@cliffy/command';
-import { createCommand } from './create.ts';
 import { getVersion } from '../utils/mod.ts';
+import { t } from '../i18n/mod.ts';
+import { createCommand } from './mod.ts';

-await new Command()
-    .name('systemd-timer')
-    .version(await getVersion())
-    .description('CLI Tool zum Erzeugen von systemd .timer und .service Units')
-    .command('create', createCommand)
-    .parse(Deno.args);
+export async function createCli() {
+    return new Command()
+        .name('systemd-timer')
+        .version(await getVersion())
+        .description(t('cli_description'))
+        .command('create', createCommand());
+}
--- a/src/cli/mod.ts
+++ b/src/cli/mod.ts
@@ -0,0 +1,2 @@
+export { createCommand } from './create.ts';
+export { createCli } from './main.ts';
--- a/src/i18n/tests/i18n.test.ts
+++ b/src/i18n/tests/i18n.test.ts
@@ -0,0 +1,32 @@
+import { assertEquals } from 'https://deno.land/std@0.224.0/assert/mod.ts';
+import { getCurrentLanguage, loadLocale, t } from '../mod.ts';
+
+Deno.test('loadLocale lade Deutsche Übersetzung', async () => {
+    await loadLocale('de');
+    assertEquals(
+        t('error_write_units'),
+        'Fehler beim Schreiben der Units:',
+    );
+    assertEquals(
+        t('unit_written_service', { path: '/tmp/service' }),
+        'Service Unit geschrieben in: /tmp/service',
+    );
+});
+
+Deno.test('t gibt den Schlüssel zurück, wenn dieser nicht gefunden wird', () => {
+    const result = t('non_existent_key');
+    assertEquals(result, 'non_existent_key');
+});
+
+Deno.test('getCurrentLanguage gibt die Fallback Sprache zurück', () => {
+    Deno.env.delete('SYSTEMD_TIMER_LANG');
+    Deno.env.delete('LC_ALL');
+    Deno.env.delete('LC_MESSAGES');
+    Deno.env.delete('LANG');
+    assertEquals(getCurrentLanguage(), 'en');
+});
+
+Deno.test('getCurrentLanguage nutz die `SYSTEMD_TIMER_LANG`, wenn gesetzt', () => {
+    Deno.env.set('SYSTEMD_TIMER_LANG', 'de_DE.UTF-8');
+    assertEquals(getCurrentLanguage(), 'de');
+});
--- a/src/i18n/de.jsonc
+++ b/src/i18n/de.jsonc
@@ -0,0 +1,32 @@
+{
+    // General
+    "cli_description": "CLI-Tool zum Erzeugen von systemd .timer und .service Units",
+    "cli_create_description": "Erzeugt eine systemd .service und .timer Unit",
+    // Options
+    "option_name": "Name der Unit-Dateien (optional, wird sonst aus dem Exec generiert)",
+    "option_exec": "Kommando, das durch systemd ausgeführt werden soll",
+    "option_calendar": "OnCalendar-Ausdruck für den Timer",
+    "option_description": "Beschreibung des Timers",
+    "option_user": "Erstellt die Unit als User-Timer",
+    "option_run_as": "Führe den systemweiten Timer als bestimmter Benutzer aus (setzt User= in der Service-Unit)",
+    "option_home": "HOME-Variable für den Service setzen",
+    "option_cwd": "Arbeitsverzeichnis (WorkingDirectory) für den Service-Prozess",
+    "option_output": "Zielverzeichnis der Unit-Dateien",
+    "option_after": "Optionales After= für die Service-Unit",
+    "option_environment": "Environment-Variablen im Format KEY=VALUE",
+    "option_logfile": "Dateipfad für Log-Ausgabe (stdout/stderr)",
+    "option_dry_run": "Gibt die Unit-Dateien nur aus, ohne sie zu schreiben",
+    // Messages
+    "unit_written_service": "Service Unit geschrieben in: {path}",
+    "unit_written_timer": "Timer Unit geschrieben in: {path}",
+    "hint_header": "\nℹ️  Hinweis:",
+    // Error messages
+    "error_write_units": "Fehler beim Schreiben der Units:",
+    "rollback_failed": "Rollback fehlgeschlagen:",
+    "error_invalid_env": "Ungültiges Environment-Format. Verwende KEY=VALUE.",
+    "error_path_schold_not_be_empty": "Pfad darf nicht leer sein.",
+    "error_path_not_found": "Pfad nicht gefunden: {path}",
+    "error_value_should_not_be_empty": "Wert ({label}) sollte nicht leer sein.",
+    "error_invalid_identifier": "Ungültiger Bezeichner: '{value}' für {identifier}. Erlaubt sind nur alphanumerische Zeichen, Unterstriche und Bindestriche.",
+    "error_invalid_calendar": "Ungültiger OnCalendar-Ausdruck: {value}. Bitte überprüfe die Syntax."
+}
--- a/src/i18n/en.jsonc
+++ b/src/i18n/en.jsonc
@@ -0,0 +1,32 @@
+{
+    // General
+    "cli_description": "CLI tool for generating systemd .timer and .service units",
+    "cli_create_description": "Generates a systemd .service and .timer unit",
+    // Options
+    "option_name": "Name of the unit files (optional, otherwise derived from the exec command)",
+    "option_exec": "Command to be executed by systemd",
+    "option_calendar": "OnCalendar expression for the timer",
+    "option_description": "Description of the timer",
+    "option_user": "Creates the unit as a user timer",
+    "option_run_as": "Runs the system-wide timer as a specific user (sets User= in the service unit)",
+    "option_home": "Sets the HOME variable for the service",
+    "option_cwd": "Working directory (WorkingDirectory) for the service process",
+    "option_output": "Target directory for the unit files",
+    "option_after": "Optional After= directive for the service unit",
+    "option_environment": "Environment variables in the format KEY=VALUE",
+    "option_logfile": "File path for log output (stdout/stderr)",
+    "option_dry_run": "Only outputs the unit files without writing them",
+    // Messages
+    "unit_written_service": "Service unit written to: {path}",
+    "unit_written_timer": "Timer unit written to: {path}",
+    "hint_header": "\nℹ️  Note:",
+    // Error messages
+    "error_write_units": "Error while writing unit files:",
+    "rollback_failed": "Rollback failed:",
+    "error_invalid_env": "Invalid environment format. Use KEY=VALUE.",
+    "error_path_schold_not_be_empty": "Path should not be empty.",
+    "error_path_not_found": "Path not found: {path}",
+    "error_value_should_not_be_empty": "Value ({label}) should not be empty.",
+    "error_invalid_identifier": "Invalid identifier: '{value}' for {identifier}. Only alphanumeric characters, underscores, and hyphens are allowed.",
+    "error_invalid_calendar": "Invalid OnCalendar expression: {value}. Please check the syntax."
+}
--- a/src/i18n/i18n.ts
+++ b/src/i18n/i18n.ts
@@ -0,0 +1,82 @@
+import { parse as parseJsonc } from '@std/jsonc';
+
+/**
+ * Initializes the i18n module by loading
+ * the appropriate locale file based on the system language.
+ */
+export async function initI18n(): Promise<void> {
+    await loadLocale(getCurrentLanguage());
+}
+
+/**
+ * Contains the loaded translations for the current language.
+ * The keys represent i18n identifiers, the values are the localized strings.
+ */
+let translations: Record<string, string> = {};
+
+/**
+ * Loads the translation file for the specified locale.
+ *
+ * Accepts both `.jsonc` (JSON with comments) and plain `.json`.
+ * When both exist, `.jsonc` takes precedence.
+ * Falls back to English ('en') if the specified file does not exist.
+ *
+ * @param locale - The language code (e.g., 'de', 'en') to load
+ * @returns Promise that resolves once the translations have been loaded
+ */
+export async function loadLocale(locale: string): Promise<void> {
+    const extensions = ['jsonc', 'json'];
+    for (const ext of extensions) {
+        try {
+            const localeUrl = new URL(`./${locale}.${ext}`, import.meta.url);
+            const raw = await Deno.readTextFile(localeUrl);
+            // parseJsonc tolerates both pure JSON and JSONC, so we can use it for either.
+            translations = parseJsonc(raw) as Record<string, string>;
+            return;
+        } catch (err) {
+            if (err instanceof Deno.errors.NotFound) {
+                // Continue with next extension.
+                continue;
+            }
+            console.error(`Error parsing locale '${locale}.${ext}':`, err);
+            break;
+        }
+    }
+    if (locale !== 'en') {
+        console.warn(`Locale '${locale}' not found – falling back to 'en'.`);
+        await loadLocale('en');
+    }
+}
+
+/**
+ * Translates a given key using the loaded translation data.
+ * Replaces placeholders in the format `{variable}` with the provided values.
+ *
+ * @param key - The i18n key (e.g., 'timer_created')
+ * @param vars - Optional replacements for placeholders in the string
+ * @returns The translated string, or the key itself if no translation is found
+ */
+export function t(key: string, vars: Record<string, string> = {}): string {
+    let text = translations[key] ?? key;
+    for (const [k, v] of Object.entries(vars)) {
+        text = text.replace(`{${k}}`, v);
+    }
+    return text;
+}
+
+/**
+ * Determines the current language from the system environment.
+ *
+ * Priority: SYSTEMD_TIMER_LANG > LC_ALL > LC_MESSAGES > LANG.
+ *
+ * @returns The language code (e.g., 'de', 'en'), defaults to 'en'
+ */
+export function getCurrentLanguage(): string {
+    return (
+        Deno.env.get('SYSTEMD_TIMER_LANG') ??
+            Deno.env.get('LC_ALL') ??
+            Deno.env.get('LC_MESSAGES') ??
+            Deno.env.get('LANG') ??
+            'en'
+    ).split('.')[0].split('_')[0].toLowerCase();
+}
--- a/src/i18n/mod.ts
+++ b/src/i18n/mod.ts
@@ -0,0 +1 @@
+export { getCurrentLanguage, initI18n, loadLocale, t } from './i18n.ts';
--- a/src/mod.ts
+++ b/src/mod.ts
@@ -1,5 +1,8 @@
-import './cli/main.ts';
+import { createCli } from './cli/mod.ts';
+import { initI18n } from './i18n/mod.ts';

 // ────────────────────────────────────────────────
 // Entry Point for CLI
-// Delegates to src/cli/main.ts, which registers all CLI commands
+
+await initI18n();
+await (await createCli()).parse(Deno.args);
--- a/src/templates/tests/generate.test.ts
+++ b/src/templates/tests/generate.test.ts
@@ -1,4 +1,5 @@
 import {
+    assert,
    assertStringIncludes,
 } from 'https://deno.land/std@0.224.0/assert/mod.ts';
 import { TimerOptions } from '../../types/mod.ts';
@@ -53,3 +54,63 @@ Deno.test('generateUnits berücksichtigt environment und logfile', () => {
    assertStringIncludes(serviceUnit, 'StandardOutput=append:/var/log/job.log');
    assertStringIncludes(serviceUnit, 'StandardError=append:/var/log/job.log');
 });
+
+Deno.test('generateUnits berücksichtigt runAs', () => {
+    const opts: TimerOptions = {
+        exec: '/bin/true',
+        calendar: 'daily',
+        runAs: 'myuser',
+    };
+    const { serviceUnit } = generateUnits('job', opts);
+
+    assertStringIncludes(serviceUnit, 'User=myuser');
+});
+
+Deno.test('generateUnits berücksichtigt home', () => {
+    const opts: TimerOptions = {
+        exec: '/bin/true',
+        calendar: 'daily',
+        home: '/home/myuser',
+    };
+    const { serviceUnit } = generateUnits('job', opts);
+
+    assertStringIncludes(serviceUnit, 'Environment=HOME=/home/myuser');
+});
+
+Deno.test('generateUnits berücksichtigt cwd', () => {
+    const opts: TimerOptions = {
+        exec: '/bin/true',
+        calendar: 'daily',
+        cwd: '/srv/app',
+    };
+    const { serviceUnit } = generateUnits('job', opts);
+
+    assertStringIncludes(serviceUnit, 'WorkingDirectory=/srv/app');
+});
+
+Deno.test('generateUnits verwendet default.target bei User-Timern', () => {
+    const opts: TimerOptions = {
+        exec: '/bin/true',
+        calendar: 'daily',
+        user: true,
+    };
+    const { timerUnit } = generateUnits('job', opts);
+
+    assertStringIncludes(timerUnit, 'WantedBy=default.target');
+});
+
+Deno.test('generateUnits ignoriert runAs bei --user', () => {
+    const opts = {
+        exec: '/bin/true',
+        calendar: 'daily',
+        user: true,
+        runAs: 'should-not-appear',
+    };
+
+    const { serviceUnit } = generateUnits('job', opts);
+
+    assert(
+        !serviceUnit.includes('User=should-not-appear'),
+        'User= sollte bei --user nicht enthalten sein',
+    );
+});
--- a/src/templates/unit-generator.ts
+++ b/src/templates/unit-generator.ts
@@ -1,3 +1,4 @@
+import { t } from '../i18n/mod.ts';
 import { TimerOptions } from '../types/mod.ts';
 import { deriveNameFromExec, writeUnitFiles } from '../utils/mod.ts';

@@ -21,13 +22,13 @@ export async function generateUnitFiles(options: TimerOptions): Promise<void> {

        if (result) {
            const { servicePath, timerPath } = result;
-            console.log(`Service Unit geschrieben in: ${servicePath}`);
-            console.log(`Timer Unit geschrieben in: ${timerPath}`);
+            console.log(t('unit_written_service', { path: servicePath }));
+            console.log(t('unit_written_timer', { path: timerPath }));
        } else {
            return;
        }

-        console.log(`\nℹ️  Hinweis:`);
+        console.log(t('hint_header'));

        if (options.user) {
            console.log(`  systemctl --user daemon-reload`);
@@ -51,14 +52,18 @@ export function generateUnits(name: string, options: TimerOptions): {
        `[Service]`,
        `Type=oneshot`,
        `ExecStart=${options.exec}`,
+        ...(options.cwd ? [`WorkingDirectory=${options.cwd}`] : []),
        ...(options.environment?.map((e) => `Environment=${e}`) ?? []),
+        ...(options.home ? [`Environment=HOME=${options.home}`] : []),
+        ...(options.logfile
+            ? [
+                `StandardOutput=append:${options.logfile}`,
+                `StandardError=append:${options.logfile}`,
+            ]
+            : []),
+        ...(options.runAs && !options.user ? [`User=${options.runAs}`] : []),
    ];

-    if (options.logfile) {
-        unitParts.push(`StandardOutput=append:${options.logfile}`);
-        unitParts.push(`StandardError=append:${options.logfile}`);
-    }
-
    const serviceUnit = unitParts.join('\n');

    const timerParts = [
@@ -70,7 +75,7 @@ export function generateUnits(name: string, options: TimerOptions): {
        `Persistent=true`,
        ``,
        `[Install]`,
-        `WantedBy=timers.target`,
+        `WantedBy=${options.user ? 'default.target' : 'timers.target'}`,
    ];

    const timerUnit = timerParts.join('\n');
--- a/src/types/options.ts
+++ b/src/types/options.ts
@@ -4,6 +4,9 @@ export interface TimerOptions {
    calendar: string;
    description?: string;
    user?: boolean;
+    runAs?: string;
+    home?: string;
+    cwd?: string;
    output?: string;
    after?: string[];
    environment?: string[];
--- a/src/utils/tests/cliValidationHelper.test.ts
+++ b/src/utils/tests/cliValidationHelper.test.ts
@@ -0,0 +1,145 @@
+import { resolve } from 'https://deno.land/std@0.224.0/path/mod.ts';
+import { ValidationError } from '@cliffy/command';
+import {
+    collectAndValidateAfter,
+    collectAndValidateEnv,
+    validateIdentifier,
+    validateNotEmpty,
+    validatePath,
+    validateSystemdCalendar,
+} from '../mod.ts';
+import { t } from '../../i18n/mod.ts';
+import {
+    assertEquals,
+    assertThrows,
+} from 'https://deno.land/std@0.224.0/assert/mod.ts';
+
+Deno.test(
+    'collectAndValidateEnv: throws ValidationError for invalid env format',
+    () => {
+        const invalidEnv = 'INVALID_ENV';
+        assertThrows(
+            () => collectAndValidateEnv(invalidEnv),
+            ValidationError,
+            t('error_invalid_env', { value: invalidEnv }),
+        );
+    },
+);
+
+Deno.test(
+    'collectAndValidateEnv: returns collected array for valid env format',
+    () => {
+        const validEnv = 'KEY=value';
+        const previous = ['EXISTING=env'];
+        const result = collectAndValidateEnv(validEnv, previous);
+        assertEquals(result, ['EXISTING=env', 'KEY=value']);
+    },
+);
+
+Deno.test('collectAndValidateEnv: aggregates multiple calls', () => {
+    const first = collectAndValidateEnv('FOO=bar');
+    const second = collectAndValidateEnv('BAZ=qux', first);
+    assertEquals(second, ['FOO=bar', 'BAZ=qux']);
+});
+
+Deno.test(
+    'validatePath: returns absolute path for valid path without existence check',
+    () => {
+        const tmpDir = Deno.makeTempDirSync();
+        const relativePath = `${tmpDir}/testfile.txt`;
+        const result = validatePath(relativePath, false);
+        assertEquals(result, resolve(relativePath));
+    },
+);
+
+Deno.test(
+    'validatePath: throws ValidationError for non‑existent path with existence check',
+    () => {
+        const tmpDir = Deno.makeTempDirSync();
+        const nonExistentPath = `${tmpDir}/nonexistent.txt`;
+        assertThrows(
+            () => validatePath(nonExistentPath, true),
+            ValidationError,
+            t('error_path_not_found', { path: resolve(nonExistentPath) }),
+        );
+    },
+);
+
+Deno.test(
+    'validatePath: returns absolute path for existing path with existence check',
+    () => {
+        const tmpDir = Deno.makeTempDirSync();
+        const existingPath = `${tmpDir}/existing.txt`;
+        Deno.writeTextFileSync(existingPath, 'test content');
+        const result = validatePath(existingPath, true);
+        assertEquals(result, resolve(existingPath));
+    },
+);
+
+Deno.test('validatePath: throws ValidationError for empty path', () => {
+    const invalidPath = '';
+    assertThrows(
+        () => validatePath(invalidPath, true),
+        ValidationError,
+        t('error_path_schold_not_be_empty'),
+    );
+});
+
+Deno.test('validateNotEmpty: returns value for non‑empty string', () => {
+    const input = 'some-value';
+    const result = validateNotEmpty(input, '--exec');
+    assertEquals(result, input);
+});
+
+Deno.test('validateNotEmpty: throws ValidationError for empty string', () => {
+    const input = '';
+    assertThrows(
+        () => validateNotEmpty(input, '--exec'),
+        ValidationError,
+        t('error_value_should_not_be_empty', { label: '--exec' }),
+    );
+});
+
+Deno.test('collectAndValidateAfter: returns aggregated array', () => {
+    const first = collectAndValidateAfter('network.target');
+    const second = collectAndValidateAfter('postgres.service', first);
+    assertEquals(second, ['network.target', 'postgres.service']);
+});
+
+Deno.test('collectAndValidateAfter: throws ValidationError for empty value', () => {
+    assertThrows(
+        () => collectAndValidateAfter(''),
+        ValidationError,
+        t('error_value_should_not_be_empty', { label: '--after' }),
+    );
+});
+
+Deno.test('validateIdentifier: returns value for valid identifier', () => {
+    const id = 'backup_job-1';
+    const result = validateIdentifier(id, '--name');
+    assertEquals(result, id);
+});
+
+Deno.test('validateIdentifier: throws ValidationError for invalid identifier', () => {
+    const id = 'invalid$';
+    assertThrows(
+        () => validateIdentifier(id, '--name'),
+        ValidationError,
+        t('error_invalid_identifier', { label: '--name', value: id }),
+    );
+});
+
+Deno.test('validateSystemdCalendar: accepts valid expression', async () => {
+    const valid = 'Mon..Fri 12:00';
+    const result = await validateSystemdCalendar(valid);
+    assertEquals(result, valid);
+});
+
+Deno.test('validateSystemdCalendar: rejects invalid expression', async () => {
+    const invalid = 'Mo..Fr 12:00';
+    await assertThrows(
+        () => validateSystemdCalendar(invalid),
+        ValidationError,
+        t('error_invalid_calendar', { value: invalid }),
+    );
+});
--- a/src/utils/tests/fs.test.ts
+++ b/src/utils/tests/fs.test.ts
@@ -3,11 +3,13 @@ import {
    assertExists,
    assertStringIncludes,
 } from 'https://deno.land/std@0.224.0/assert/mod.ts';
+import { stub } from 'https://deno.land/std@0.224.0/testing/mock.ts';
+import { exists } from 'https://deno.land/std@0.224.0/fs/mod.ts';
 import { join } from 'https://deno.land/std@0.224.0/path/mod.ts';
 import { resolveUnitTargetPath, writeUnitFiles } from '../mod.ts';
 import { TimerOptions } from '../../types/options.ts';

-Deno.test('writeUnitFiles schreibt .service und .timer korrekt', async () => {
+Deno.test('writeUnitFiles: writes .service and .timer files correctly', async () => {
    const tmp = await Deno.makeTempDir({ prefix: 'test-units-' });

    const options = {
@@ -26,15 +28,15 @@ Deno.test('writeUnitFiles schreibt .service und .timer korrekt', async () => {
        options as TimerOptions,
    ) as { servicePath: string; timerPath: string };

-    // Überprüfe Pfade
+    // Check file paths
    assertEquals(servicePath, join(tmp, 'test-backup.service'));
    assertEquals(timerPath, join(tmp, 'test-backup.timer'));

-    // Existieren Dateien?
+    // Check if files exist
    assertExists(await Deno.stat(servicePath));
    assertExists(await Deno.stat(timerPath));

-    // Enthält die Datei den erwarteten Inhalt?
+    // Check if file contents match expectations
    const readService = await Deno.readTextFile(servicePath);
    const readTimer = await Deno.readTextFile(timerPath);

@@ -42,18 +44,237 @@ Deno.test('writeUnitFiles schreibt .service und .timer korrekt', async () => {
    assertStringIncludes(readTimer, 'OnCalendar=daily');
 });

-Deno.test('resolveUnitTargetPath mit --output', () => {
+Deno.test('resolveUnitTargetPath: with --output', () => {
    const result = resolveUnitTargetPath({ output: '/tmp/units', user: false });
    assertEquals(result, '/tmp/units');
 });

-Deno.test('resolveUnitTargetPath mit --user ohne output', () => {
+Deno.test('resolveUnitTargetPath: with --user and no output', () => {
    Deno.env.set('HOME', '/home/maxp');
    const result = resolveUnitTargetPath({ output: undefined, user: true });
    assertEquals(result, '/home/maxp/.config/systemd/user');
 });

-Deno.test('resolveUnitTargetPath ohne output und ohne user', () => {
+Deno.test('resolveUnitTargetPath: with no output and no user', () => {
    const result = resolveUnitTargetPath({ output: undefined, user: false });
    assertEquals(result, '/etc/systemd/system');
 });
+
+Deno.test('writeUnitFiles: error writing .timer file triggers rollback', async () => {
+    const tmp = await Deno.makeTempDir();
+
+    const options: TimerOptions = {
+        output: tmp,
+        user: false,
+        exec: '/bin/true',
+        calendar: 'never',
+    };
+
+    const name = 'fail-timer';
+    const serviceContent = '[Service]\nExecStart=/bin/true';
+    const timerContent = '[Timer]\nOnCalendar=never';
+
+    const servicePath = join(tmp, `${name}.service`);
+    const timerPath = join(tmp, `${name}.timer`);
+
+    // Simulate: writing the .timer file fails
+    const originalWrite = Deno.writeTextFile;
+    const writeStub = stub(
+        Deno,
+        'writeTextFile',
+        async (path: string | URL, data: string | ReadableStream<string>) => {
+            if (typeof path === 'string' && path.endsWith('.timer')) {
+                throw new Error('Simulated write error');
+            } else {
+                return await originalWrite(path, data);
+            }
+        },
+    );
+
+    const result = await writeUnitFiles(
+        name,
+        serviceContent,
+        timerContent,
+        options,
+    );
+
+    // Expect: function returns undefined
+    assertEquals(result, undefined);
+
+    // Expect: both files have been deleted (rollback)
+    assertEquals(await exists(servicePath), false);
+    assertEquals(await exists(timerPath), false);
+
+    writeStub.restore();
+});
+
+Deno.test('writeUnitFiles: error writing .service file prevents further actions', async () => {
+    const tmp = await Deno.makeTempDir();
+
+    const options: TimerOptions = {
+        output: tmp,
+        user: false,
+        exec: '/bin/true',
+        calendar: 'weekly',
+    };
+
+    const name = 'fail-service';
+    const serviceContent = '[Service]\nExecStart=/bin/true';
+    const timerContent = '[Timer]\nOnCalendar=weekly';
+
+    const servicePath = join(tmp, `${name}.service`);
+    const timerPath = join(tmp, `${name}.timer`);
+
+    // Simulate: error writing the .service file
+    const writeStub = stub(
+        Deno,
+        'writeTextFile',
+        (path: string | URL, _data: string | ReadableStream<string>) => {
+            if (typeof path === 'string' && path.endsWith('.service')) {
+                throw new Error('Simulated service write error');
+            }
+            return Promise.resolve();
+        },
+    );
+
+    const result = await writeUnitFiles(
+        name,
+        serviceContent,
+        timerContent,
+        options,
+    );
+
+    // Expect: function returns undefined
+    assertEquals(result, undefined);
+
+    // Expect: no files were created
+    assertEquals(await exists(servicePath), false);
+    assertEquals(await exists(timerPath), false);
+
+    writeStub.restore();
+});
+
+Deno.test('writeUnitFiles: both files written, then error → full rollback', async () => {
+    const tmp = await Deno.makeTempDir();
+
+    const options: TimerOptions = {
+        output: tmp,
+        user: false,
+        exec: '/bin/true',
+        calendar: 'never',
+    };
+
+    const name = 'fail-after-write';
+    const serviceContent = '[Service]\nExecStart=/bin/true';
+    const timerContent = '[Timer]\nOnCalendar=never';
+
+    const servicePath = join(tmp, `${name}.service`);
+    const timerPath = join(tmp, `${name}.timer`);
+
+    let writeCount = 0;
+    const originalWriteTextFile = Deno.writeTextFile;
+
+    const writeStub = stub(
+        Deno,
+        'writeTextFile',
+        async (path: string | URL, data: string | ReadableStream<string>) => {
+            if (typeof path !== 'string') {
+                throw new Error('Unexpected path type');
+            }
+
+            // Simulate both writes, then throw an error after the second
+            writeCount++;
+
+            await originalWriteTextFile(path, data);
+
+            if (writeCount === 2) {
+                throw new Error('Simulated error after full write');
+            }
+        },
+    );
+
+    const result = await writeUnitFiles(
+        name,
+        serviceContent,
+        timerContent,
+        options,
+    );
+
+    // Expect: function returns undefined
+    assertEquals(result, undefined);
+
+    // Expect: both files were removed
+    assertEquals(await exists(servicePath), false);
+    assertEquals(await exists(timerPath), false);
+
+    writeStub.restore();
+});
+
+Deno.test('writeUnitFiles: rollback fails if files cannot be deleted', async () => {
+    const tmp = await Deno.makeTempDir();
+
+    const options: TimerOptions = {
+        output: tmp,
+        user: false,
+        exec: '/bin/true',
+        calendar: 'never',
+    };
+
+    const name = 'rollback-error';
+    const serviceContent = '[Service]\nExecStart=/bin/true';
+    const timerContent = '[Timer]\nOnCalendar=never';
+
+    const servicePath = join(tmp, `${name}.service`);
+    const timerPath = join(tmp, `${name}.timer`);
+
+    const originalWriteTextFile = Deno.writeTextFile;
+    const _originalRemove = Deno.remove;
+
+    let writeCount = 0;
+
+    const writeStub = stub(
+        Deno,
+        'writeTextFile',
+        async (path: string | URL, data: string | ReadableStream<string>) => {
+            writeCount++;
+            await originalWriteTextFile(path, data);
+            if (writeCount === 2) {
+                throw new Error('Error after full write');
+            }
+        },
+    );
+
+    const removeStub = stub(
+        Deno,
+        'remove',
+        // deno-lint-ignore require-await
+        async (_path: string | URL, _opts?: Deno.RemoveOptions) => {
+            throw new Error('Deletion forbidden!');
+        },
+    );
+
+    const logs: string[] = [];
+    const consoleStub = stub(console, 'error', (...args) => {
+        logs.push(args.map((a) => String(a)).join(' '));
+    });
+
+    const result = await writeUnitFiles(
+        name,
+        serviceContent,
+        timerContent,
+        options,
+    );
+    assertEquals(result, undefined);
+
+    // Files still exist because deletion failed
+    assertEquals(await exists(servicePath), true);
+    assertEquals(await exists(timerPath), true);
+
+    // Error output contains "rollback_failed"
+    const combinedLogs = logs.join('\n');
+    assertStringIncludes(combinedLogs, 'rollback_failed');
+
+    writeStub.restore();
+    removeStub.restore();
+    consoleStub.restore();
+});
--- a/src/utils/cliValidationHelper.ts
+++ b/src/utils/cliValidationHelper.ts
@@ -0,0 +1,176 @@
+import { ValidationError } from '@cliffy/command';
+import { t } from '../i18n/mod.ts';
+import { existsSync } from 'https://deno.land/std@0.224.0/fs/mod.ts';
+import { resolve } from 'https://deno.land/std@0.224.0/path/mod.ts';
+
+/**
+ * Collects repeated occurrences of the `--environment` CLI option and validates
+ * that every entry adheres to `KEY=value` syntax.
+ *
+ * Cliffy calls this handler for *each* `--environment` argument. The previously
+ * accumulated values are passed in via the `previous` parameter, allowing us to
+ * build up the final array manually.
+ *
+ * @example
+ * ```ts
+ * // CLI invocation:
+ * //   mycli --environment FOO=bar --environment BAZ=qux
+ * const env = collectAndValidateEnv("FOO=bar");
+ * const env2 = collectAndValidateEnv("BAZ=qux", env);
+ * console.log(env2); // => ["FOO=bar", "BAZ=qux"]
+ * ```
+ *
+ * @param value - Current `KEY=value` string supplied by the user.
+ * @param previous - Array of values collected so far (defaults to an empty
+ *   array on the first call).
+ * @returns The updated array containing all validated `KEY=value` pairs.
+ *
+ * @throws {ValidationError} If the input does not match the required syntax
+ *   The resulting error is caught by Cliffy, which
+ *   will print a help message and terminate with a non-zero exit code.
+ */
+export function collectAndValidateEnv(
+    value: string,
+    previous: string[] = [],
+): string[] {
+    if (!/^\w+=.+/.test(value)) {
+        throw new ValidationError(t('error_invalid_env', { value }));
+    }
+    previous.push(value);
+    return previous;
+}
+
+/**
+ * Normalises a given path to its absolute representation and optionally checks
+ * whether it exists on the filesystem.
+ *
+ * @remarks
+ * Because `--home`, `--cwd`, `--output`, and similar options may refer to files
+ * or directories that *must* already exist, this helper performs the common
+ * validation in a single place.
+ *
+ * @param value - Path provided by the user (absolute or relative).
+ * @param mustExist - When `true`, the function asserts that the resolved path
+ *   exists; otherwise, existence is not verified.
+ * @returns The absolute path derived via {@linkcode resolve}.
+ *
+ * @throws {ValidationError}
+ *  - If `value` is empty or not a string.
+ *  - If `mustExist` is `true` **and** the resolved path cannot be found.
+ */
+export function validatePath(value: string, mustExist: boolean): string {
+    if (!value || typeof value !== 'string') {
+        throw new ValidationError(t('error_path_schold_not_be_empty'));
+    }
+    const abs = resolve(value);
+    if (mustExist && !existsSync(abs)) {
+        throw new ValidationError(t('error_path_not_found', { path: abs }));
+    }
+    return abs;
+}
+
+/**
+ * Ensures that a mandatory CLI argument is not empty.
+ *
+ * @param value - Raw string supplied by the user.
+ * @param label - Human-readable label identifying the option (used in error
+ *   messages). Example: `"--exec"`.
+ * @returns The original `value` if the validation passes.
+ *
+ * @throws {ValidationError} When `value` is `""`, `null`, `undefined`, or a
+ *   non-string.
+ */
+export function validateNotEmpty(value: string, label: string): string {
+    if (!value || typeof value !== 'string') {
+        throw new ValidationError(
+            t('error_value_should_not_be_empty', { label }),
+        );
+    }
+    return value;
+}
+
+/**
+ * Collects repeated occurrences of the `--after` CLI option, validating each
+ * target unit name and returning the aggregated list.
+ *
+ * The validation performed here is intentionally minimal – it merely checks
+ * that the argument is a non-empty string. Detailed identifier rules (ASCII
+ * characters, digits, etc.) are enforced elsewhere by
+ * {@link validateIdentifier} when appropriate.
+ *
+ * @param value - Unit name provided with the current `--after` occurrence.
+ * @param previous - Accumulated array of unit names (defaults to an empty
+ *   array).
+ * @returns An array containing all validated `--after` values.
+ *
+ * @throws {ValidationError} If `value` is empty.
+ */
+export function collectAndValidateAfter(
+    value: string,
+    previous: string[] = [],
+): string[] {
+    if (!value || typeof value !== 'string') {
+        throw new ValidationError(
+            t('error_value_should_not_be_empty', { label: '--after' }),
+        );
+    }
+    previous.push(value);
+    return previous;
+}
+
+/**
+ * Validates identifiers used in generated systemd unit file names (e.g.
+ * service or timer names) and option flags like `--run-as`.
+ *
+ * @example
+ * ```ts
+ * validateIdentifier("backup_job", "--name");   // OK
+ * validateIdentifier("foo.bar-baz", "--after"); // OK
+ * validateIdentifier("oops$", "--name");        // throws ValidationError
+ * ```
+ *
+ * @param value - The identifier string to validate.
+ * @param label - The relevant option flag, forwarded to the error message so
+ *   the user immediately sees which argument is wrong.
+ * @returns The unchanged `value` when it satisfies the pattern.
+ *
+ * @throws {ValidationError} If `value` contains characters outside the allowed
+ *   set of ASCII letters, digits, `.`, `_`, and `-`.
+ */
+export function validateIdentifier(value: string, label: string): string {
+    if (!/^[A-Za-z0-9_.-]+$/.test(value)) {
+        throw new ValidationError(
+            t('error_invalid_identifier', { identifier: label, value }),
+        );
+    }
+    return value;
+}
+
+/**
+ * Validates a systemd OnCalendar expression by invoking `systemd-analyze calendar`
+ * as a subprocess using a synchronous call. This avoids async overhead.
+ *
+ * @remarks
+ * Requires a Linux environment with systemd available.
+ *
+ * @param value - Calendar expression to validate
+ * @returns The original `value` if valid
+ * @throws {ValidationError} If the expression is invalid or systemd rejects it
+ */
+export function validateSystemdCalendar(value: string): string {
+    const command = new Deno.Command('systemd-analyze', {
+        args: ['calendar', value],
+        stdout: 'null',
+        stderr: 'null',
+    });
+
+    const { success } = command.outputSync();
+
+    if (!success) {
+        throw new ValidationError(
+            t('error_invalid_calendar', { value }),
+        );
+    }
+
+    return value;
+}
--- a/src/utils/fs.ts
+++ b/src/utils/fs.ts
@@ -1,6 +1,7 @@
 import { ensureDir, exists } from 'https://deno.land/std@0.224.0/fs/mod.ts';
 import { join } from 'https://deno.land/std@0.224.0/path/mod.ts';
 import { TimerOptions } from '../types/mod.ts';
+import { t } from '../i18n/mod.ts';

 export async function writeUnitFiles(
    name: string,
@@ -28,9 +29,9 @@ export async function writeUnitFiles(
                await Deno.remove(timerPath);
            }
        } catch (rollbackError) {
-            console.error('Rollback fehlgeschlagen:', rollbackError);
+            console.error(t('rollback_failed'), rollbackError);
        }
-        console.error('Fehler beim Schreiben der Units:', error);
+        console.error(t('error_write_units'), error);
        return undefined;
    }

--- a/src/utils/mod.ts
+++ b/src/utils/mod.ts
@@ -1,3 +1,11 @@
+export {
+    collectAndValidateAfter,
+    collectAndValidateEnv,
+    validateIdentifier,
+    validateNotEmpty,
+    validatePath,
+    validateSystemdCalendar,
+} from './cliValidationHelper.ts';
 export { resolveUnitTargetPath, writeUnitFiles } from './fs.ts';
 export { deriveNameFromExec } from './misc.ts';
 export { getVersion } from './version.ts';
Author	SHA1	Message	Date
ghost-bot	971d1ecf90	chore(changelog): update changelog for v0.5.1 All checks were successful Upload Assets / upload-assets (arm64, linux) (release) Successful in 1m31s Details Upload Assets / upload-assets (amd64, linux) (release) Successful in 1m34s Details	2025-06-15 14:52:14 +00:00
Max P.	6bd93223f6	chore(version): bump to 0.5.1 All checks were successful Auto Changelog & Release / release (push) Successful in 6s Details CI / build (push) Successful in 15s Details	2025-06-15 16:52:05 +02:00
ghost-bot	b3f9075a01	chore(changelog): update unreleased changelog	2025-06-15 14:51:30 +00:00
Max P.	05f3b519f5	chore(workflows): simplify release workflow with auto-changelog All checks were successful Auto Changelog & Release / release (push) Successful in 6s Details CI / build (push) Successful in 23s Details - Replaces custom release and changelog logic with auto-changelog action - Reduces complexity and maintenance effort in the release process - Ensures consistent changelog generation and release creation	2025-06-15 16:51:21 +02:00
Max P.	3a1ee0cfd6	feat(install): add support for compressed .zst archives - Introduces detection for 'zstd' to handle .zst archives if available - Adds checksum verification and decompression for .zst files - Falls back to uncompressed binary download if 'zstd' is unavailable - Improves installation flexibility and reduces binary download size	2025-06-15 16:51:21 +02:00
Max P.	d9183d2f04	feat(workflows): add zstd compression for build artifacts - Introduce zstd compression for build artifacts to reduce file size - Generate and upload SHA256 checksum for compressed archives - Enhance artifact handling in release workflows	2025-06-15 16:51:21 +02:00
ghost-bot	88bae5ef3e	chore(changelog): update unreleased changelog	2025-06-14 15:42:16 +00:00
Max P.	6efc1515ed	chore(workflows): add locked flag to cargo install for git-cliff All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 3s Details Auto Changelog & Release / changelog-only (push) Successful in 12s Details CI / build (push) Successful in 22s Details Auto Changelog & Release / release (push) Has been skipped Details - Ensures reproducible builds by adding the `--locked` flag to cargo install - Improves dependency resolution consistency during git-cliff installation	2025-06-14 17:41:59 +02:00
ghost-bot	1dee6111bd	chore(changelog): update unreleased changelog	2025-05-30 11:01:07 +00:00
Max P.	ce78cf3a9a	docs(readme): add input validation and multilingual support All checks were successful CI / build (push) Successful in 13s Details Auto Changelog & Release / detect-version-change (push) Successful in 3s Details Auto Changelog & Release / changelog-only (push) Successful in 7s Details Auto Changelog & Release / release (push) Has been skipped Details - Document validation of inputs, e.g., systemd `OnCalendar` expressions - Highlight added multilingual support for English and German	2025-05-30 13:00:38 +02:00
ghost-bot	a7f18f0b80	chore(changelog): update changelog for v0.5.0 All checks were successful Upload Assets / upload-assets (amd64, linux) (release) Successful in 28s Details Upload Assets / upload-assets (arm64, linux) (release) Successful in 28s Details	2025-05-30 10:48:57 +00:00
Max P.	871d0e26a7	chore(version): bump version to 0.5.0 All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 2s Details Auto Changelog & Release / changelog-only (push) Has been skipped Details CI / build (push) Successful in 13s Details Auto Changelog & Release / release (push) Successful in 8s Details	2025-05-30 12:48:43 +02:00
ghost-bot	f984f79452	chore(changelog): update unreleased changelog	2025-05-30 10:47:56 +00:00
ghost-bot	3f3ce2ca0d	chore(changelog): update unreleased changelog All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 3s Details Auto Changelog & Release / release (push) Has been skipped Details Auto Changelog & Release / changelog-only (push) Successful in 6s Details CI / build (push) Successful in 13s Details	2025-05-30 12:47:32 +02:00
Max P.	28b23cf947	chore(lock): update dependencies to latest versions	2025-05-30 12:47:24 +02:00
Max P.	1c07af402b	feat(cli): add validation for command options	2025-05-30 12:47:24 +02:00
Max P.	3d95706d68	feat(validation): add CLI validation helpers for input checks - Introduce functions to validate CLI inputs like paths, identifiers, and environment variables - Add error messages for invalid inputs to support user feedback - Include unit tests to ensure correctness and robustness of validation logic	2025-05-30 12:47:23 +02:00
Max P.	ccb04e4982	feat(build): add run permissions to compiled binaries	2025-05-30 12:47:23 +02:00
ghost-bot	2abe90e9aa	chore(changelog): update unreleased changelog	2025-05-30 10:24:22 +00:00
Max P.	531a02a6e1	feat(ci): add compile steps to CI workflow All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 3s Details Auto Changelog & Release / release (push) Has been skipped Details Auto Changelog & Release / changelog-only (push) Successful in 7s Details CI / build (push) Successful in 15s Details - Introduces compile steps for amd64 and arm64 targets in CI workflow - Updates failure condition to include compile step outcomes - Enhances local CI task to include amd64 build process	2025-05-30 12:24:10 +02:00
Max P.	f3f2c61da0	fix(build): update included files to use .jsonc format	2025-05-30 12:23:51 +02:00
0xMax42	32d472a606	chore(pr): Support JSONC locale files and update i18n handling #4 All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 2s Details Auto Changelog & Release / release (push) Has been skipped Details CI / build (push) Successful in 7s Details Auto Changelog & Release / changelog-only (push) Successful in 5s Details - Add `@std/jsonc` as a dependency in `deno.jsonc` and `deno.lock` - Update i18n loader to support `.jsonc` files with comments - Rename locale files from `.json` to `.jsonc` and add inline comments - Set VSCode to use Deno JSONC formatter for `jsonc` files This change enables the i18n module to load translation files written in JSONC format, allowing for inline comments and improved readability. The `@std/jsonc` library is added as a dependency and used to parse both JSON and JSONC files. The loader prioritizes `.jsonc` files when both `.json` and `.jsonc` exist. VSCode settings are updated to use the Deno formatter for JSONC files. Locale files are renamed and enhanced with comments for clarity. Merged from feature/change-language-json-to-jsonc into main	2025-05-30 11:46:33 +02:00
ghost-bot	c6d5bf60fc	chore(changelog): update unreleased changelog All checks were successful CI / build (pull_request) Successful in 7s Details	2025-05-30 09:45:37 +00:00
Max P.	c7af1fb6ca	feat(vscode): add JSONC formatter configuration All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 2s Details Auto Changelog & Release / release (push) Has been skipped Details Auto Changelog & Release / changelog-only (push) Successful in 6s Details	2025-05-30 11:45:15 +02:00
Max P.	5226269ec2	style(i18n): add comments for clarity and rename files - Adds inline comments to JSON files to improve readability - Renames `.json` files to `.jsonc` to support comments - Improves organization of translation entries	2025-05-30 11:45:00 +02:00
Max P.	4ac5dd4c88	feat(i18n): support loading JSONC translation files - Adds support for `.jsonc` format alongside `.json` for locale files - Prioritizes `.jsonc` format when both file types are available	2025-05-30 11:44:09 +02:00
Max P.	8f1cb3fad7	feat(config): add @std/jsonc dependency - Adds @std/jsonc dependency to improve JSONC handling capabilities - Updates lock file to include integrity and dependency data for @std/jsonc	2025-05-30 11:43:46 +02:00
0xMax42	f4c7b2e18f	chore(pr): add rollback tests and update test descriptions #3 All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 2s Details CI / build (push) Successful in 6s Details Auto Changelog & Release / release (push) Has been skipped Details Auto Changelog & Release / changelog-only (push) Successful in 5s Details - Add tests for rollback behavior in `writeUnitFiles` on errors - Simulate file write and delete failures in test scenarios - Log rollback failures when file deletion is not possible - Update all test descriptions and comments to English - Add `testing/mock.ts` dependency in `deno.lock` This change adds comprehensive tests for the `writeUnitFiles` function to verify that files are properly rolled back if errors occur during their creation. The tests simulate failures when writing `.service` or `.timer` files, as well as when file deletion is blocked, and check that the function responds by cleaning up as expected or logging rollback failures. All test comments and descriptions have been updated to English for clarity. The `testing/mock.ts` dependency was added to enable function stubbing in tests. #2 Merged from test/fail-write-and-rollback into main	2025-05-30 11:21:41 +02:00
ghost-bot	84a883fd8f	chore(changelog): update unreleased changelog	2025-05-30 09:21:20 +00:00
ghost-bot	e5f9f2c45a	chore(changelog): update unreleased changelog All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 2s Details Auto Changelog & Release / release (push) Has been skipped Details CI / build (pull_request) Successful in 6s Details Auto Changelog & Release / changelog-only (push) Successful in 7s Details	2025-05-30 11:21:10 +02:00
Max P.	f3c46e1222	chore(deps): update deno.lock with new dependency - Adds a new dependency to deno.lock for testing utilities	2025-05-30 11:21:10 +02:00
Max P.	c4f4614a2d	test(fs): update test descriptions and comments to English - Translate all test descriptions and inline comments from German to English	2025-05-30 11:21:10 +02:00
Max P.	6039d236eb	test(fs): add rollback tests for writeUnitFiles errors - Add tests to verify rollback behavior when file writing fails - Simulate various error scenarios to ensure proper cleanup - Log rollback failures when file deletion is prohibited	2025-05-30 11:21:10 +02:00
Max P.	333341d3fd	chore(pr): add default merge message template All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 3s Details CI / build (push) Successful in 7s Details Auto Changelog & Release / release (push) Has been skipped Details Auto Changelog & Release / changelog-only (push) Successful in 6s Details - Introduces a template for merge messages in pull requests - Standardizes format with placeholders for PR details	2025-05-30 11:20:46 +02:00
ghost-bot	38afcf210e	chore(changelog): update changelog for v0.4.1 All checks were successful Upload Assets / upload-assets (amd64, linux) (release) Successful in 28s Details Upload Assets / upload-assets (arm64, linux) (release) Successful in 29s Details	2025-05-28 16:34:22 +00:00
Max P.	28b18dc994	chore(version): bump version to 0.4.1 All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 3s Details Auto Changelog & Release / changelog-only (push) Has been skipped Details CI / build (push) Successful in 7s Details Auto Changelog & Release / release (push) Successful in 7s Details	2025-05-28 18:34:09 +02:00
ghost-bot	ede012317b	chore(changelog): update unreleased changelog	2025-05-28 16:34:01 +00:00
Max P.	a22c156dd3	fix(tasks): add read permissions to build scripts All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 3s Details CI / build (push) Successful in 6s Details Auto Changelog & Release / release (push) Has been skipped Details Auto Changelog & Release / changelog-only (push) Successful in 6s Details - Allow read permissions in build scripts for both amd64 and arm64 targets - Ensure compatibility with files required during the build process	2025-05-28 18:33:47 +02:00
ghost-bot	d648d5a3f1	chore(changelog): update changelog for v0.4.0 All checks were successful Upload Assets / upload-assets (amd64, linux) (release) Successful in 28s Details Upload Assets / upload-assets (arm64, linux) (release) Successful in 27s Details	2025-05-28 16:17:26 +00:00
Max P.	bb51982f6e	chore(version): bump to 0.4.0 All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 3s Details Auto Changelog & Release / changelog-only (push) Has been skipped Details CI / build (push) Successful in 6s Details Auto Changelog & Release / release (push) Successful in 13s Details	2025-05-28 18:17:07 +02:00
ghost-bot	3416610486	chore(changelog): update unreleased changelog	2025-05-28 16:15:06 +00:00
Max P.	54d71ba3f0	style(i18n): add missing newline at EOF in JSON files All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 2s Details CI / build (push) Successful in 7s Details Auto Changelog & Release / release (push) Has been skipped Details Auto Changelog & Release / changelog-only (push) Successful in 6s Details - Ensures JSON files adhere to standard formatting by adding a newline at the end of the file.	2025-05-28 18:14:51 +02:00
Max P.	c02da70902	feat(vscode): enable Deno support and configure JSON formatting - Enables Deno integration in VS Code settings - Sets the default JSON formatter to Deno's extension - Activates format-on-save for improved workflow	2025-05-28 18:14:51 +02:00
Max P.	9ad407e531	feat(ci): add CI workflow with format, lint, and test steps - Introduces a CI workflow triggered on push, pull requests, and manual dispatch - Includes steps for code formatting, linting, and testing using Deno - Fails the workflow if any of the steps do not succeed	2025-05-28 18:14:51 +02:00
Max P.	07730e5761	feat(tasks): add formatting, linting, and CI tasks - Introduces new tasks for code formatting and linting - Adds a CI task combining formatting, linting, and testing	2025-05-28 18:14:51 +02:00
ghost-bot	1f79c1a15a	chore(changelog): update unreleased changelog	2025-05-28 16:10:19 +00:00
Max P.	440130f782	feat(tasks): include localization files in build commands All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 3s Details Auto Changelog & Release / release (push) Has been skipped Details Auto Changelog & Release / changelog-only (push) Successful in 6s Details - Add German and English localization files to build outputs - Ensure compiled binaries include required resources for i18n support	2025-05-28 18:10:04 +02:00
Max P.	2a13ee2539	refactor(cli): integrate i18n support across commands - Centralize CLI text strings using the i18n module for localization - Refactor `createCommand` and `createCli` to improve modularity - Update logging and error messages to use translated strings	2025-05-28 18:09:52 +02:00
Max P.	8efbee1ba9	test(i18n): add unit tests for localization functions - Add tests for `loadLocale` to verify translations load correctly - Add tests for `t` to ensure fallback behavior for missing keys - Add tests for `getCurrentLanguage` to validate language detection logic	2025-05-28 18:09:24 +02:00
Max P.	bd5ea80aff	feat(i18n): add German and English translations for CLI tool - Introduce localization files for German and English languages - Provide translations for CLI tool options and error messages	2025-05-28 18:09:16 +02:00
Max P.	c9b4c8bd71	feat(i18n): add i18n module for localization support - Introduce functions to initialize and load locale files dynamically - Add support for translation keys with placeholder replacements - Default to English if locale files are missing or not found - Determine system language using environment variables	2025-05-28 18:09:04 +02:00
Max P.	dfa92d8069	chore(vscode): update folder listener with i18n directory - Adds the /src/i18n directory to the folder listener configuration - Ensures changes in the i18n folder are tracked as part of the setup	2025-05-28 18:08:37 +02:00
ghost-bot	ef052e9f66	chore(changelog): update changelog for v0.3.1 All checks were successful Upload Assets / upload-assets (arm64, linux) (release) Successful in 29s Details Upload Assets / upload-assets (amd64, linux) (release) Successful in 43s Details	2025-05-28 12:40:53 +00:00
Max P.	c53576a700	chore(version): bump version to 0.3.1 All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 3s Details Auto Changelog & Release / changelog-only (push) Has been skipped Details Auto Changelog & Release / release (push) Successful in 8s Details	2025-05-28 14:40:42 +02:00
ghost-bot	3d74ec37e4	chore(changelog): update unreleased changelog	2025-05-28 12:40:16 +00:00
Max P.	c4855ed3fb	style(workflows): fix formatting and whitespace issues All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 3s Details Auto Changelog & Release / release (push) Has been skipped Details Auto Changelog & Release / changelog-only (push) Successful in 7s Details - Standardize quotes in branch matching patterns - Remove unnecessary trailing whitespace - Add export of author and committer dates for consistent tags - Ensure proper environment variable alignment	2025-05-28 14:39:42 +02:00
Max P.	07ee03b6be	chore(version): bump version to 0.3.0 All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 3s Details Auto Changelog & Release / changelog-only (push) Has been skipped Details Auto Changelog & Release / release (push) Successful in 8s Details	2025-05-28 14:26:02 +02:00
Max P.	fb2a62d984	docs(readme): expand CLI option descriptions for clarity - Add detailed explanations for each CLI option in README files - Improve consistency and formatting for better readability - Highlight supported features and usage comprehensively	2025-05-28 14:26:02 +02:00
Max P.	113103f368	feat(cli): add options for user, home, and working directory - Add `--run-as` option to specify user for system-wide timers - Add `--home` option to set the HOME environment variable - Add `--cwd` option to define the working directory - Update tests to validate new options and behavior	2025-05-28 14:26:02 +02:00
ghost-bot	f112002249	chore(changelog): update unreleased changelog	2025-05-26 15:27:10 +00:00
Max P.	0c1d8be79f	chore(workflows): consolidate release sync into upload workflow All checks were successful Auto Changelog & Release / detect-version-change (push) Successful in 3s Details Auto Changelog & Release / release (push) Has been skipped Details Auto Changelog & Release / changelog-only (push) Successful in 6s Details - Remove separate workflow for syncing releases to GitHub - Integrate release sync steps into the upload-assets workflow - Simplify workflow management and reduce duplication	2025-05-26 17:27:00 +02:00
@@ -1 +1 @@
 .2.3
 .5.1
				`@@ -0,0 +1 @@`
				`export { getCurrentLanguage, initI18n, loadLocale, t } from './i18n.ts';`