diff --git a/.github/workflows/ci-default.yml b/.github/workflows/ci-default.yml
index febdaaf..fd8abd6 100644
--- a/.github/workflows/ci-default.yml
+++ b/.github/workflows/ci-default.yml
@@ -3,39 +3,48 @@ name: CI default branch
 on:
   push:
     branches: [development]
+  pull_request:
+    branches: [development]
 
 jobs:
   linting:
+    name: Run linters
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
-      - name: Run linters
+      - name: Checkout code
+        uses: actions/checkout@v2
+      - name: Setup Node
         uses: actions/setup-node@v2
         with:
           node-version: 16.x
           cache: "npm"
-      - run: npm ci
-      - run: make ci/linting
+      - name: Install Node modules
+        run: npm ci
+      - name: Run eslint
+        run: make ci/linting
 
   testing:
+    name: Run tests on ${{ matrix.os }} for Node ${{ matrix.node-version }}
     needs: linting
     strategy:
       matrix:
         os: [ubuntu-latest, windows-latest]
         node-version: [14.x, 16.x]
-
     runs-on: ${{ matrix.os }}
 
     steps:
-      - uses: actions/checkout@v2
-      - name: OS ${{ matrix.os }} - Node ${{ matrix.node-version }}
+      - name: Checkout code
+        uses: actions/checkout@v2
+      - name: Setup OS ${{ matrix.os }} - Node ${{ matrix.node-version }}
         uses: actions/setup-node@v2
         with:
           node-version: ${{ matrix.node-version }}
           cache: "npm"
-      - run: npm ci
-      - run: make ci/coverage
-      - name: Coveralls
+      - name: Install Node modules
+        run: npm ci
+      - name: Run tests with Jest
+        run: make ci/coverage
+      - name: Prepare coverage result
         uses: coverallsapp/github-action@master
         with:
           github-token: ${{ secrets.GITHUB_TOKEN }}
@@ -44,10 +53,11 @@ jobs:
           parallel: true
 
   finish:
+    name: Indicate completion to Coveralls.io
     needs: testing
     runs-on: ubuntu-latest
     steps:
-      - name: Coveralls Finished
+      - name: Finished coverage collection
         uses: coverallsapp/github-action@master
         with:
           github-token: ${{ secrets.GITHUB_TOKEN }}
diff --git a/.github/workflows/ci-feature.yml b/.github/workflows/ci-feature.yml
deleted file mode 100644
index 4db0384..0000000
--- a/.github/workflows/ci-feature.yml
+++ /dev/null
@@ -1,55 +0,0 @@
-name: CI feature branches / pull requests
-
-on:
-  pull_request:
-    branches: [development]
-
-jobs:
-  linting:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - name: Run linters
-        uses: actions/setup-node@v2
-        with:
-          node-version: 16.x
-          cache: "npm"
-      - run: npm ci
-      - run: make ci/linting
-
-  testing:
-    needs: linting
-    strategy:
-      matrix:
-        os: [ubuntu-latest, windows-latest]
-        node-version: [14.x, 16.x]
-
-    runs-on: ${{ matrix.os }}
-
-    steps:
-      - uses: actions/checkout@v2
-      - name: OS ${{ matrix.os }} - Node ${{ matrix.node-version }}
-        uses: actions/setup-node@v2
-        with:
-          node-version: ${{ matrix.node-version }}
-          cache: "npm"
-      - run: npm ci
-      - run: make ci/coverage
-      - name: Coveralls
-        uses: coverallsapp/github-action@master
-        with:
-          github-token: ${{ secrets.GITHUB_TOKEN }}
-          flag-name: OS-${{ matrix.os }}_Node-${{ matrix.node-version }}
-          path-to-lcov: ./src/.coverage/lcov.info
-          parallel: true
-
-  finish:
-    needs: testing
-    runs-on: ubuntu-latest
-    steps:
-      - name: Coveralls Finished
-        uses: coverallsapp/github-action@master
-        with:
-          github-token: ${{ secrets.GITHUB_TOKEN }}
-          path-to-lcov: ./src/.coverage/lcov.info
-          parallel-finished: true
diff --git a/.github/workflows/ci-release.yml b/.github/workflows/ci-release.yml
index 64e2383..e9165f9 100644
--- a/.github/workflows/ci-release.yml
+++ b/.github/workflows/ci-release.yml
@@ -6,17 +6,23 @@ on:
 
 jobs:
   build:
+    name: Release to npm
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
-      # Setup .npmrc file to publish to npm
-      - uses: actions/setup-node@v2
+      - name: Checkout code
+        uses: actions/checkout@v2
+      - name: Setup Node
+        uses: actions/setup-node@v2
         with:
           node-version: "16.x"
           registry-url: "https://registry.npmjs.org"
-      - run: npm ci
-      - run: make ci/linting
-      - run: make ci/testing
-      - run: make ci/release
+      - name: Install Node modules
+        run: npm ci
+      - name: Run linters
+        run: make ci/linting
+      - name: Run test suite
+        run: make ci/testing
+      - name: Perform the release
+        run: make ci/release
         env:
           NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}
diff --git a/Makefile b/Makefile
index a45883c..d059477 100644
--- a/Makefile
+++ b/Makefile
@@ -98,7 +98,7 @@ dev/coverage : | $(STAMP_NODE_INSTALL)
 
 # Run the test suite.
 dev/test : | $(STAMP_NODE_INSTALL)
-	npx jest --config .jestrc.json --verbose
+	npx jest --config .jestrc.json --verbose main.spec.ts
 .PHONY : dev/test
 
 # Run eslint against all files in the current directory.
diff --git a/README.md b/README.md
index 5fde3fe..0176ee0 100644
--- a/README.md
+++ b/README.md
@@ -19,7 +19,7 @@ providing a manifest file to match the orginal filename to the new one.
 Just install _buster_ from **npm**:
 
 ```bash
-npm install --save-dev @mischback/buster
+$ npm install --save-dev @mischback/buster
 ```
 
 Most likely you will want to install it as a development dependency for internal
@@ -30,11 +30,65 @@ usage.
 After installation, _buster_ is available using the following command:
 
 ```bash
-npx buster
+$ npx buster
+```
+
+### Example Usage
+
+```bash
+$ tree .manual-test
+.manual-test
+├── blank.css
+├── index.ts
+└── lib
+    └── hashwalker.ts
+
+$ npx buster -i "./.manual-test" -e "ts"
+[date and time]  INFO [buster] No mode specified, using "copy"
+[date and time]  INFO [buster] No output file specified, using "asset-manifest.json"
+
+$ tree .manual-test
+.manual-test
+├── asset-manifest.json
+├── blank.css
+├── index.dd99a19417.ts
+├── index.ts
+└── lib
+    ├── hashwalker.84f1a289e8.ts
+    └── hashwalker.ts
+
+$ cat .manual-test/asset-manifest.json
+{"index.ts":"index.dd99a19417.ts","lib/hashwalker.ts":"lib/hashwalker.84f1a289e8.ts"}%
 ```
 
 ## Configuration
 
+_buster_ is configured by command line parameters.
+
+- `--commonPathLength`: manually override the length of filepath's that is to be
+  preserved in the manifest file
+- `--debug`, `-d`: activate debug mode, providing more log messages
+  - default: `false`
+- `--extension`, `-e`: a file extension to include during processing; may be specified multiple times
+  - default: `["css", "js"]`
+- `--hashLength`: the length of the hash to be appended to the filename
+  - default: `10`
+- `--input`, `-i`: the actual input file or directory
+  - **mandator parameter**, no default value
+- `--mode`, `-m`: operation mode, either `"copy"` or `"rename"`
+  - default: `copy`
+  - `MODE_COPY` as specified by `copy` will copy the source file to a new file
+    with the content's hash appended to the filename
+  - `MODE_RENAME` as specified by `rename` will rename the existing file
+- `--outFile`, `-o`: filename and path of the manifest file to be created
+  - default: `"asset-manifest.json"`
+  - **Please note:** If just a filename is specified, the output file will be
+    created relative to `input`: if `input` is a directory, it will be placed
+    inside this directory; if `input` is a file, it will be placed into the same
+    directory; if a path and filename is specified, that location will be useds
+- `--quiet`, `-q`: suppress all log messages
+  - default: `false`
+
 ## Contributing
 
 Issues, pull requests and feature requests are welcome. Just use the project's
diff --git a/package-lock.json b/package-lock.json
index c60b263..5f7c40e 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -10,6 +10,7 @@
       "license": "MIT",
       "dependencies": {
         "@mischback/fileobject-walker": "1.0.0",
+        "@mischback/min-async-json-interface": "1.0.1",
         "stdio": "2.1.1",
         "tslog": "3.2.2"
       },
@@ -995,6 +996,11 @@
       "resolved": "https://registry.npmjs.org/@mischback/fileobject-walker/-/fileobject-walker-1.0.0.tgz",
       "integrity": "sha512-oa47jI73e4iJ8UF9kVYIPGLyBz25yF7iTLiO4ze7aEwk89MokiJ5smWFHgCnyw2CJCrrbtk1DaSjVpgj84uxEQ=="
     },
+    "node_modules/@mischback/min-async-json-interface": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/@mischback/min-async-json-interface/-/min-async-json-interface-1.0.1.tgz",
+      "integrity": "sha512-MOtAEXojYHO8iv6g9LkmBbrnG11R0dqJm1ACVWAsWsgh3FwSmDIgJGMoyq7rV6kLhIB1w9gdl1ohRCZfKIj35w=="
+    },
     "node_modules/@nodelib/fs.scandir": {
       "version": "2.1.5",
       "resolved": "https://registry.npmjs.org/@nodelib/fs.scandir/-/fs.scandir-2.1.5.tgz",
@@ -2148,9 +2154,9 @@
       }
     },
     "node_modules/electron-to-chromium": {
-      "version": "1.3.895",
-      "resolved": "https://registry.npmjs.org/electron-to-chromium/-/electron-to-chromium-1.3.895.tgz",
-      "integrity": "sha512-9Ww3fB8CWctjqHwkOt7DQbMZMpal2x2reod+/lU4b9axO1XJEDUpPMBxs7YnjLhhqpKXIIB5SRYN/B4K0QpvyQ==",
+      "version": "1.3.896",
+      "resolved": "https://registry.npmjs.org/electron-to-chromium/-/electron-to-chromium-1.3.896.tgz",
+      "integrity": "sha512-NcGkBVXePiuUrPLV8IxP43n1EOtdg+dudVjrfVEUd/bOqpQUFZ2diL5PPYzbgEhZFEltdXV3AcyKwGnEQ5lhMA==",
       "dev": true
     },
     "node_modules/emittery": {
@@ -6383,6 +6389,11 @@
       "resolved": "https://registry.npmjs.org/@mischback/fileobject-walker/-/fileobject-walker-1.0.0.tgz",
       "integrity": "sha512-oa47jI73e4iJ8UF9kVYIPGLyBz25yF7iTLiO4ze7aEwk89MokiJ5smWFHgCnyw2CJCrrbtk1DaSjVpgj84uxEQ=="
     },
+    "@mischback/min-async-json-interface": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/@mischback/min-async-json-interface/-/min-async-json-interface-1.0.1.tgz",
+      "integrity": "sha512-MOtAEXojYHO8iv6g9LkmBbrnG11R0dqJm1ACVWAsWsgh3FwSmDIgJGMoyq7rV6kLhIB1w9gdl1ohRCZfKIj35w=="
+    },
     "@nodelib/fs.scandir": {
       "version": "2.1.5",
       "resolved": "https://registry.npmjs.org/@nodelib/fs.scandir/-/fs.scandir-2.1.5.tgz",
@@ -7259,9 +7270,9 @@
       }
     },
     "electron-to-chromium": {
-      "version": "1.3.895",
-      "resolved": "https://registry.npmjs.org/electron-to-chromium/-/electron-to-chromium-1.3.895.tgz",
-      "integrity": "sha512-9Ww3fB8CWctjqHwkOt7DQbMZMpal2x2reod+/lU4b9axO1XJEDUpPMBxs7YnjLhhqpKXIIB5SRYN/B4K0QpvyQ==",
+      "version": "1.3.896",
+      "resolved": "https://registry.npmjs.org/electron-to-chromium/-/electron-to-chromium-1.3.896.tgz",
+      "integrity": "sha512-NcGkBVXePiuUrPLV8IxP43n1EOtdg+dudVjrfVEUd/bOqpQUFZ2diL5PPYzbgEhZFEltdXV3AcyKwGnEQ5lhMA==",
       "dev": true
     },
     "emittery": {
diff --git a/package.json b/package.json
index 62931b9..102c9cd 100644
--- a/package.json
+++ b/package.json
@@ -26,6 +26,7 @@
   "homepage": "https://github.com/Mischback/buster#readme",
   "dependencies": {
     "@mischback/fileobject-walker": "1.0.0",
+    "@mischback/min-async-json-interface": "1.0.1",
     "stdio": "2.1.1",
     "tslog": "3.2.2"
   },
diff --git a/src/lib/json-interface.spec.ts b/src/lib/json-interface.spec.ts
deleted file mode 100644
index 6a29220..0000000
--- a/src/lib/json-interface.spec.ts
+++ /dev/null
@@ -1,112 +0,0 @@
-// SPDX-License-Identifier: MIT
-
-/* test specific imports */
-import { describe, expect, it, jest } from "@jest/globals";
-
-/* mock library imports */
-jest.mock("fs/promises");
-
-/* import the subject under test (SUT) */
-import {
-  JsonInterfaceError,
-  loadJsonFromFile,
-  writeJsonToFile,
-} from "./json-interface";
-
-/* additional imports */
-import { readFile, writeFile } from "fs/promises";
-
-describe("loadJsonFromFile()...", () => {
-  it("...rejects with an error if readFile() fails", () => {
-    /* define the parameter */
-    const testFile = "testfile";
-
-    /* setup mocks and spies */
-    (readFile as jest.Mock).mockRejectedValue(new Error("foo"));
-
-    /* make the assertions */
-    return loadJsonFromFile(testFile).catch((err) => {
-      expect(err).toBeInstanceOf(JsonInterfaceError);
-      expect(readFile).toHaveBeenCalledTimes(1);
-      expect(readFile).toHaveBeenCalledWith(testFile, expect.anything());
-    });
-  });
-
-  it("...rejects with an error if JSON.parse() fails", () => {
-    /* define the parameter */
-    const testFile = "testfile";
-
-    /* setup mocks and spies */
-    (readFile as jest.Mock).mockResolvedValue("foo");
-    JSON.parse = jest.fn(() => {
-      throw new Error("foo");
-    });
-
-    /* make the assertions */
-    return loadJsonFromFile(testFile).catch((err) => {
-      expect(err).toBeInstanceOf(JsonInterfaceError);
-      expect(readFile).toHaveBeenCalledTimes(1);
-      expect(readFile).toHaveBeenCalledWith(testFile, expect.anything());
-      expect(JSON.parse).toHaveBeenCalledTimes(1);
-      expect(JSON.parse).toHaveBeenCalledWith("foo");
-    });
-  });
-
-  it("...resolves with parsed JSON object", () => {
-    /* define the parameter */
-    const testFile = "testfile";
-    const testResult = { foo: "bar" };
-
-    /* setup mocks and spies */
-    (readFile as jest.Mock).mockResolvedValue("foo");
-    JSON.parse = jest.fn().mockReturnValue(testResult);
-
-    /* make the assertions */
-    return loadJsonFromFile(testFile).then((retVal) => {
-      expect(retVal).toStrictEqual(testResult);
-      expect(readFile).toHaveBeenCalledTimes(1);
-      expect(readFile).toHaveBeenCalledWith(testFile, expect.anything());
-      expect(JSON.parse).toHaveBeenCalledTimes(1);
-      expect(JSON.parse).toHaveBeenCalledWith("foo");
-    });
-  });
-});
-
-describe("writeJsonToFile()...", () => {
-  it("...rejects with an error if writeFile() fails", () => {
-    /* define the parameter */
-    const testFile = "testfile";
-    const testJson = { foo: "bar" } as unknown;
-
-    /* setup mocks and spies */
-    (writeFile as jest.Mock).mockRejectedValue(new Error("foo"));
-
-    /* make the assertions */
-    return writeJsonToFile(testFile, testJson).catch((err) => {
-      expect(err).toBeInstanceOf(JsonInterfaceError);
-      expect(writeFile).toHaveBeenCalledTimes(1);
-      expect(writeFile).toHaveBeenCalledWith(testFile, expect.anything());
-    });
-  });
-
-  it("...resolves if writeFile() succeeds", () => {
-    /* define the parameter */
-    const testFile = "testfile";
-    const testJson = { foo: "bar" } as unknown;
-
-    /* setup mocks and spies */
-    (writeFile as jest.Mock).mockResolvedValue(undefined);
-    JSON.stringify = jest.fn((_value: any) => {
-      return "foo";
-    });
-
-    /* make the assertions */
-    return writeJsonToFile(testFile, testJson).then((retVal) => {
-      expect(retVal).toBe(undefined);
-      expect(writeFile).toHaveBeenCalledTimes(1);
-      expect(writeFile).toHaveBeenCalledWith(testFile, expect.anything());
-      expect(JSON.stringify).toHaveBeenCalledTimes(1);
-      expect(JSON.stringify).toHaveBeenCalledWith(testJson);
-    });
-  });
-});
diff --git a/src/lib/json-interface.ts b/src/lib/json-interface.ts
deleted file mode 100644
index a557163..0000000
--- a/src/lib/json-interface.ts
+++ /dev/null
@@ -1,70 +0,0 @@
-// SPDX-License-Identifier: MIT
-
-/* library imports */
-import { readFile, writeFile } from "fs/promises";
-
-export class JsonInterfaceError extends Error {
-  originalError: Error;
-
-  constructor(message: string, err: Error) {
-    super(message);
-    this.originalError = err;
-  }
-}
-
-/**
- * Read a given file and parse its content as JSON
- *
- * @param filename - The file to be read provided as string
- * @returns A Promise, resolving to the file content as JSON
- *
- * The returned JSON object will be of type "unknown" and must be casted to
- * the required target type.
- */
-export function loadJsonFromFile(filename: string): Promise<unknown> {
-  return new Promise((resolve, reject) => {
-    readFile(filename, "utf-8")
-      .then((fileContent) => {
-        try {
-          const parsedContent = JSON.parse(fileContent) as unknown;
-          return resolve(parsedContent);
-        } catch (err) {
-          return reject(
-            new JsonInterfaceError(
-              `Error while parsing content of "${filename}"`,
-              err as Error
-            )
-          );
-        }
-      })
-      .catch((err: Error) => {
-        return reject(
-          new JsonInterfaceError(`Could not read "${filename}"`, err)
-        );
-      });
-  });
-}
-
-/**
- * Write a given object to a file in JSON
- *
- * @param filename - The file to be written to
- * @param jsonData - The object to be written to the file
- * @returns A Promise, resolving to 0 of type JsonInterfaceRetValSuccess
- */
-export function writeJsonToFile(
-  filename: string,
-  jsonData: unknown
-): Promise<void> {
-  return new Promise((resolve, reject) => {
-    writeFile(filename, JSON.stringify(jsonData))
-      .then(() => {
-        return resolve();
-      })
-      .catch((err: Error) => {
-        return reject(
-          new JsonInterfaceError(`Could not write to file "${filename}"`, err)
-        );
-      });
-  });
-}
diff --git a/src/lib/manifest.spec.ts b/src/lib/manifest.spec.ts
index dde00b6..0eac99a 100644
--- a/src/lib/manifest.spec.ts
+++ b/src/lib/manifest.spec.ts
@@ -4,14 +4,14 @@
 import { beforeAll, describe, expect, it, jest } from "@jest/globals";
 
 /* mock library imports */
-jest.mock("./json-interface");
+jest.mock("@mischback/min-async-json-interface");
 
 /* import the subject under test (SUT) */
 import { BusterManifestError, createManifestFile } from "./manifest";
 
 /* additional imports */
+import { writeJsonToFile } from "@mischback/min-async-json-interface";
 import { BusterConfig, MODE_COPY } from "./configure";
-import { writeJsonToFile } from "./json-interface";
 import { logger } from "./logging";
 import { HashWalkerResult } from "./hashwalker/hashwalker";
 
diff --git a/src/lib/manifest.ts b/src/lib/manifest.ts
index 11f4df5..f0e5d4f 100644
--- a/src/lib/manifest.ts
+++ b/src/lib/manifest.ts
@@ -1,12 +1,12 @@
 // SPDX-License-Identifier: MIT
 
 /* library imports */
+import { writeJsonToFile } from "@mischback/min-async-json-interface";
 
 /* internal imports */
 import { BusterConfig } from "./configure";
 import { BusterError } from "./errors";
 import { HashWalkerResult } from "./hashwalker/hashwalker";
-import { writeJsonToFile } from "./json-interface";
 import { logger } from "./logging";
 
 export class BusterManifestError extends BusterError {
diff --git a/src/main.spec.ts b/src/main.spec.ts
new file mode 100644
index 0000000..233442f
--- /dev/null
+++ b/src/main.spec.ts
@@ -0,0 +1,240 @@
+// SPDX-License-Identifier: MIT
+
+/* test specific imports */
+import { beforeAll, describe, expect, it, jest } from "@jest/globals";
+
+/* mock library imports */
+jest.mock("./lib/configure");
+jest.mock("./lib/logging");
+jest.mock("./lib/manifest");
+jest.mock("./lib/hashwalker/hashwalker");
+
+/* import the subject under test (SUT) */
+import { busterMain } from "./main";
+
+/* additional imports */
+import { FileObjectWalkerError } from "@mischback/fileobject-walker";
+import {
+  applyDebugConfiguration,
+  logger,
+  suppressLogOutput,
+} from "./lib/logging";
+import { getConfig, BusterConfigError, checkConfig } from "./lib/configure";
+import { BusterManifestError, createManifestFile } from "./lib/manifest";
+import { BusterFileSystemError } from "./lib/hashwalker/filesystem";
+import { BusterHashError } from "./lib/hashwalker/hash";
+import { hashWalker } from "./lib/hashwalker/hashwalker";
+
+/* Run these before actually starting the test suite */
+beforeAll(() => {
+  /* The test subject relies on "tslog" to provide log messages.
+   * For running the test-suite, actually printing the log messages to the
+   * console is unwanted, so the output is suppressed.
+   */
+  logger.setSettings({
+    suppressStdOutput: true,
+  });
+});
+
+describe("busterMain()...", () => {
+  it("...attaches SIGINT handler", () => {
+    /* define the parameter */
+    const testArgv: string[] = ["doesn't", "matter", "-q"];
+
+    /* setup mocks and spies */
+    (getConfig as jest.Mock).mockRejectedValue(new Error("foo"));
+    const processSpy = jest.spyOn(process, "on");
+
+    /* make the assertions */
+    return busterMain(testArgv).catch((err) => {
+      expect(err).toBe(70);
+      expect(processSpy).toHaveBeenCalledTimes(1);
+    });
+  });
+
+  it("...correctly activates quiet mode", () => {
+    /* define the parameter */
+    const testArgv: string[] = ["doesn't", "matter", "-q"];
+
+    /* setup mocks and spies */
+    (getConfig as jest.Mock).mockRejectedValue(new Error("foo"));
+    (suppressLogOutput as jest.Mock).mockImplementation();
+
+    /* make the assertions */
+    return busterMain(testArgv).catch((err) => {
+      expect(err).toBe(70);
+      expect(suppressLogOutput).toHaveBeenCalledTimes(1);
+    });
+  });
+
+  it("...correctly activates debug mode", () => {
+    /* define the parameter */
+    const testArgv: string[] = ["doesn't", "matter", "-d"];
+
+    /* setup mocks and spies */
+    (getConfig as jest.Mock).mockRejectedValue(new Error("foo"));
+    (applyDebugConfiguration as jest.Mock).mockImplementation();
+
+    /* make the assertions */
+    return busterMain(testArgv).catch((err) => {
+      expect(err).toBe(70);
+      expect(applyDebugConfiguration).toHaveBeenCalledTimes(1);
+    });
+  });
+
+  it("...overrides quiet mode with debug mode", () => {
+    /* define the parameter */
+    const testArgv: string[] = ["doesn't", "matter", "-q", "-d"];
+
+    /* setup mocks and spies */
+    (getConfig as jest.Mock).mockRejectedValue(new Error("foo"));
+    (suppressLogOutput as jest.Mock).mockImplementation();
+    (applyDebugConfiguration as jest.Mock).mockImplementation();
+
+    /* make the assertions */
+    return busterMain(testArgv).catch((err) => {
+      expect(err).toBe(70);
+      expect(suppressLogOutput).toHaveBeenCalledTimes(1);
+      expect(applyDebugConfiguration).toHaveBeenCalledTimes(1);
+    });
+  });
+
+  it("...returns EXIT_CONFIG_ERROR on BusterConfigError by getConfig()", () => {
+    /* define the parameter */
+    const testArgv: string[] = ["doesn't", "matter"];
+    const testErrorMessage = "testError";
+
+    /* setup mocks and spies */
+    (getConfig as jest.Mock).mockRejectedValue(
+      new BusterConfigError(testErrorMessage)
+    );
+    const loggerErrorSpy = jest.spyOn(logger, "error");
+    const loggerFatalSpy = jest.spyOn(logger, "fatal");
+
+    /* make the assertions */
+    return busterMain(testArgv).catch((err) => {
+      expect(err).toBe(78);
+      expect(loggerErrorSpy).toHaveBeenCalledTimes(1);
+      // BusterConfigError is mocked aswell, so it does not work to access its
+      // message in an expect block.
+      // expect(loggerErrorSpy).toHaveBeenCalledWith(testErrorMessage);
+      expect(loggerFatalSpy).toHaveBeenCalledTimes(1);
+    });
+  });
+
+  it("...returns EXIT_CONFIG_ERROR on BusterConfigError by checkConfig()", () => {
+    /* define the parameter */
+    const testArgv: string[] = ["doesn't", "matter"];
+    const testErrorMessage = "testError";
+
+    /* setup mocks and spies */
+    (getConfig as jest.Mock).mockResolvedValue("foo");
+    (checkConfig as jest.Mock).mockRejectedValue(
+      new BusterConfigError(testErrorMessage)
+    );
+    const loggerErrorSpy = jest.spyOn(logger, "error");
+    const loggerFatalSpy = jest.spyOn(logger, "fatal");
+
+    /* make the assertions */
+    return busterMain(testArgv).catch((err) => {
+      expect(err).toBe(78);
+      expect(loggerErrorSpy).toHaveBeenCalledTimes(1);
+      // BusterConfigError is mocked aswell, so it does not work to access its
+      // message in an expect block.
+      // expect(loggerErrorSpy).toHaveBeenCalledWith(testErrorMessage);
+      expect(loggerFatalSpy).toHaveBeenCalledTimes(1);
+    });
+  });
+
+  it("...returns EXIT_PROCESSING_ERROR on BusterHashError", () => {
+    /* define the parameter */
+    const testArgv: string[] = ["doesn't", "matter"];
+    const testErrorMessage = "testError";
+
+    /* setup mocks and spies */
+    (getConfig as jest.Mock).mockResolvedValue("foo");
+    (checkConfig as jest.Mock).mockResolvedValue("foo");
+    (hashWalker as jest.Mock).mockRejectedValue(
+      new BusterHashError(testErrorMessage)
+    );
+    const loggerErrorSpy = jest.spyOn(logger, "error");
+    const loggerFatalSpy = jest.spyOn(logger, "fatal");
+
+    /* make the assertions */
+    return busterMain(testArgv).catch((err) => {
+      expect(err).toBe(10);
+      expect(loggerErrorSpy).toHaveBeenCalledTimes(1);
+      expect(loggerErrorSpy).toHaveBeenCalledWith(testErrorMessage);
+      expect(loggerFatalSpy).toHaveBeenCalledTimes(1);
+    });
+  });
+
+  it("...returns EXIT_PROCESSING_ERROR on BusterFileSystemError", () => {
+    /* define the parameter */
+    const testArgv: string[] = ["doesn't", "matter"];
+    const testErrorMessage = "testError";
+
+    /* setup mocks and spies */
+    (getConfig as jest.Mock).mockResolvedValue("foo");
+    (checkConfig as jest.Mock).mockResolvedValue("foo");
+    (hashWalker as jest.Mock).mockRejectedValue(
+      new BusterFileSystemError(testErrorMessage)
+    );
+    const loggerErrorSpy = jest.spyOn(logger, "error");
+    const loggerFatalSpy = jest.spyOn(logger, "fatal");
+
+    /* make the assertions */
+    return busterMain(testArgv).catch((err) => {
+      expect(err).toBe(10);
+      expect(loggerErrorSpy).toHaveBeenCalledTimes(1);
+      expect(loggerErrorSpy).toHaveBeenCalledWith(testErrorMessage);
+      expect(loggerFatalSpy).toHaveBeenCalledTimes(1);
+    });
+  });
+
+  it("...returns EXIT_PROCESSING_ERROR on FileObjectWalkerError", () => {
+    /* define the parameter */
+    const testArgv: string[] = ["doesn't", "matter"];
+    const testErrorMessage = "testError";
+
+    /* setup mocks and spies */
+    (getConfig as jest.Mock).mockResolvedValue("foo");
+    (checkConfig as jest.Mock).mockResolvedValue("foo");
+    (hashWalker as jest.Mock).mockRejectedValue(
+      new FileObjectWalkerError(testErrorMessage)
+    );
+    const loggerErrorSpy = jest.spyOn(logger, "error");
+    const loggerFatalSpy = jest.spyOn(logger, "fatal");
+
+    /* make the assertions */
+    return busterMain(testArgv).catch((err) => {
+      expect(err).toBe(10);
+      expect(loggerErrorSpy).toHaveBeenCalledTimes(1);
+      expect(loggerErrorSpy).toHaveBeenCalledWith(testErrorMessage);
+      expect(loggerFatalSpy).toHaveBeenCalledTimes(1);
+    });
+  });
+
+  it("...returns EXIT_PROCESSING_ERROR on BusterManifestError", () => {
+    /* define the parameter */
+    const testArgv: string[] = ["doesn't", "matter"];
+    const testErrorMessage = "testError";
+
+    /* setup mocks and spies */
+    (getConfig as jest.Mock).mockResolvedValue("foo");
+    (checkConfig as jest.Mock).mockResolvedValue("foo");
+    (createManifestFile as jest.Mock).mockRejectedValue(
+      new BusterManifestError(testErrorMessage)
+    );
+    const loggerErrorSpy = jest.spyOn(logger, "error");
+    const loggerFatalSpy = jest.spyOn(logger, "fatal");
+
+    /* make the assertions */
+    return busterMain(testArgv).catch((err) => {
+      expect(err).toBe(10);
+      expect(loggerErrorSpy).toHaveBeenCalledTimes(1);
+      expect(loggerErrorSpy).toHaveBeenCalledWith(testErrorMessage);
+      expect(loggerFatalSpy).toHaveBeenCalledTimes(1);
+    });
+  });
+});