diff --git a/src/application/ApplicationParser.ts b/src/application/ApplicationParser.ts
deleted file mode 100644
index b1a4700b..00000000
--- a/src/application/ApplicationParser.ts
+++ /dev/null
@@ -1,120 +0,0 @@
-import { Category } from '../domain/Category';
-import { Application } from '../domain/Application';
-import { Script } from '@/domain/Script';
-// import applicationFile from 'js-yaml-loader!@/application/application.yaml';
-// import applicationFile from 'json-loader!yaml-loader!@/application/application.yaml';
-import applicationFile, { YamlCategory, YamlScript, YamlDocumentable } from 'js-yaml-loader!./application.yaml';
-// import test from './test-loader!./test.txt';
-
-interface ApplicationResult {
-    readonly application: Application;
-    readonly selectedScripts: Script[];
-}
-
-export class ApplicationParser {
-
-    public static buildApplication(): ApplicationResult {
-        const name = applicationFile.name as string;
-        const version = applicationFile.version as number;
-        const categories = new Array<Category>();
-        const selectedScripts = new Array<Script>();
-        if (!applicationFile.actions || applicationFile.actions.length <= 0) {
-            throw new Error('Application does not define any action');
-        }
-        for (const action of applicationFile.actions) {
-            const category = ApplicationParser.parseCategory(action, selectedScripts);
-            categories.push(category);
-        }
-        const app = new Application(name, version, categories);
-        return { application: app, selectedScripts };
-    }
-
-    private static categoryIdCounter = 0;
-
-    private static parseCategory(category: YamlCategory, selectedScripts: Script[]): Category {
-        if (!category.children || category.children.length <= 0) {
-            throw Error('Category has no children');
-        }
-        const subCategories = new Array<Category>();
-        const subScripts = new Array<Script>();
-        for (const categoryOrScript of category.children) {
-            if (ApplicationParser.isCategory(categoryOrScript)) {
-                const subCategory = ApplicationParser.parseCategory(categoryOrScript as YamlCategory, selectedScripts);
-                subCategories.push(subCategory);
-            } else if (ApplicationParser.isScript(categoryOrScript)) {
-                const yamlScript = categoryOrScript as YamlScript;
-                const script = new Script(
-                    /* name */
-                    yamlScript.name,
-                    /* code */
-                    yamlScript.code,
-                    /* docs */
-                    this.parseDocUrls(yamlScript));
-                subScripts.push(script);
-                if (yamlScript.default === true) {
-                    selectedScripts.push(script);
-                }
-            } else {
-                throw new Error(`Child element is neither a category or a script.
-                        Parent: ${category.category}, element: ${categoryOrScript}`);
-            }
-        }
-        return new Category(
-            /*id*/
-            ApplicationParser.categoryIdCounter++,
-            /*name*/
-            category.category,
-            /*docs*/
-            this.parseDocUrls(category),
-            /*categories*/
-            subCategories,
-            /*scripts*/
-            subScripts,
-        );
-    }
-
-    private static parseDocUrls(documentable: YamlDocumentable): ReadonlyArray<string> {
-        const docs = documentable.docs;
-        if (!docs) {
-            return [];
-        }
-        const result = new Array<string>();
-        if (docs instanceof Array) {
-            for (const doc of docs) {
-                if (typeof doc !== 'string') {
-                    throw new Error('Docs field (documentation url) must be an array of strings');
-                }
-                this.validateUrl(doc);
-                result.push(doc);
-            }
-        } else if (typeof docs === 'string') {
-            this.validateUrl(docs);
-            result.push(docs);
-        } else {
-            throw new Error('Docs field (documentation url) must a string or array of strings');
-        }
-        return result;
-    }
-
-    private static isScript(categoryOrScript: any): boolean {
-        return categoryOrScript.code && categoryOrScript.code.length > 0;
-    }
-
-    private static isCategory(categoryOrScript: any): boolean {
-        return categoryOrScript.category && categoryOrScript.category.length > 0;
-    }
-
-    private static validateUrl(docUrl: string): void {
-        if (!docUrl) {
-            throw new Error('Documentation url is null or empty');
-        }
-        if (docUrl.includes('\n')) {
-            throw new Error('Documentation url cannot be multi-lined.');
-        }
-        const res = docUrl.match(
-            /(http(s)?:\/\/.)?(www\.)?[-a-zA-Z0-9@:%._\+~#=]{2,256}\.[a-z]{2,6}\b([-a-zA-Z0-9@:%_\+.~#?&//=]*)/g);
-        if (res == null) {
-            throw new Error(`Invalid documentation url: ${docUrl}`);
-        }
-    }
-}
diff --git a/src/application/Parser/ApplicationParser.ts b/src/application/Parser/ApplicationParser.ts
new file mode 100644
index 00000000..564f01b3
--- /dev/null
+++ b/src/application/Parser/ApplicationParser.ts
@@ -0,0 +1,29 @@
+import { Category } from '../../domain/Category';
+import { Application } from '../../domain/Application';
+import { Script } from '@/domain/Script';
+import applicationFile from 'js-yaml-loader!./../application.yaml';
+import { parseCategory } from './CategoryParser';
+
+interface ApplicationResult {
+    readonly application: Application;
+    readonly selectedScripts: Script[];
+}
+
+export function buildApplication(): ApplicationResult {
+    const name = applicationFile.name as string;
+    const version = applicationFile.version as number;
+    const categories = new Array<Category>();
+    const selectedScripts = new Array<Script>();
+    if (!applicationFile.actions || applicationFile.actions.length <= 0) {
+        throw new Error('Application does not define any action');
+    }
+    for (const action of applicationFile.actions) {
+        const category = parseCategory({
+            category: action,
+            selectedScripts,
+        });
+        categories.push(category);
+    }
+    const app = new Application(name, version, categories);
+    return { application: app, selectedScripts };
+}
diff --git a/src/application/Parser/CategoryParser.ts b/src/application/Parser/CategoryParser.ts
new file mode 100644
index 00000000..3465bc0b
--- /dev/null
+++ b/src/application/Parser/CategoryParser.ts
@@ -0,0 +1,70 @@
+import { YamlCategory, YamlScript } from 'js-yaml-loader!./application.yaml';
+import { Script } from '@/domain/Script';
+import { Category } from '../../domain/Category';
+import { parseDocUrls } from './DocumentationParser';
+
+let categoryIdCounter: number = 0;
+
+interface IParsingContext {
+    category: YamlCategory;
+    selectedScripts: Script[];
+}
+
+interface ICategoryChildren {
+    subCategories: Category[];
+    subScripts: Script[];
+}
+
+export function parseCategory(context: IParsingContext): Category {
+    if (!context.category.children || context.category.children.length <= 0) {
+        throw Error('Category has no children');
+    }
+    const children: ICategoryChildren = {
+        subCategories: new Array<Category>(),
+        subScripts: new Array<Script>(),
+    };
+    for (const categoryOrScript of context.category.children) {
+        parseCategoryChild(categoryOrScript, children, context);
+    }
+    return new Category(
+        /*id*/ categoryIdCounter++,
+        /*name*/ context.category.category,
+        /*docs*/ parseDocUrls(context.category),
+        /*categories*/ children.subCategories,
+        /*scripts*/ children.subScripts,
+    );
+}
+
+function parseCategoryChild(
+    categoryOrScript: any, children: ICategoryChildren, parent: IParsingContext) {
+    if (isCategory(categoryOrScript)) {
+        const subCategory = parseCategory(
+            {
+                category: categoryOrScript as YamlCategory,
+                selectedScripts: parent.selectedScripts,
+            });
+        children.subCategories.push(subCategory);
+    } else if (isScript(categoryOrScript)) {
+        const yamlScript = categoryOrScript as YamlScript;
+        const script = new Script(
+            /* name */  yamlScript.name,
+            /* code */ yamlScript.code,
+            /* docs */ parseDocUrls(yamlScript));
+        children.subScripts.push(script);
+        if (yamlScript.default === true) {
+            parent.selectedScripts.push(script);
+        }
+    } else {
+        throw new Error(`Child element is neither a category or a script.
+                Parent: ${parent.category.category}, element: ${categoryOrScript}`);
+    }
+}
+
+
+function isScript(categoryOrScript: any): boolean {
+    return categoryOrScript.code && categoryOrScript.code.length > 0;
+}
+
+function isCategory(categoryOrScript: any): boolean {
+    return categoryOrScript.category && categoryOrScript.category.length > 0;
+}
diff --git a/src/application/Parser/DocumentationParser.ts b/src/application/Parser/DocumentationParser.ts
new file mode 100644
index 00000000..0d0349c2
--- /dev/null
+++ b/src/application/Parser/DocumentationParser.ts
@@ -0,0 +1,49 @@
+import { YamlDocumentable } from 'js-yaml-loader!./application.yaml';
+
+export function parseDocUrls(documentable: YamlDocumentable): ReadonlyArray<string> {
+    const docs = documentable.docs;
+    if (!docs) {
+        return [];
+    }
+    const result = new DocumentationUrls();
+    if (docs instanceof Array) {
+        for (const doc of docs) {
+            if (typeof doc !== 'string') {
+                throw new Error('Docs field (documentation url) must be an array of strings');
+            }
+            result.add(doc);
+        }
+    } else if (typeof docs === 'string') {
+        result.add(docs);
+    } else {
+        throw new Error('Docs field (documentation url) must a string or array of strings');
+    }
+    return result.getAll();
+}
+
+class DocumentationUrls {
+    private readonly urls = new Array<string>();
+
+    public add(url: string) {
+        validateUrl(url);
+        this.urls.push(url);
+    }
+
+    public getAll(): ReadonlyArray<string> {
+        return this.urls;
+    }
+}
+
+function validateUrl(docUrl: string): void {
+    if (!docUrl) {
+        throw new Error('Documentation url is null or empty');
+    }
+    if (docUrl.includes('\n')) {
+        throw new Error('Documentation url cannot be multi-lined.');
+    }
+    const res = docUrl.match(
+        /(http(s)?:\/\/.)?(www\.)?[-a-zA-Z0-9@:%._\+~#=]{2,256}\.[a-z]{2,6}\b([-a-zA-Z0-9@:%_\+.~#?&//=]*)/g);
+    if (res == null) {
+        throw new Error(`Invalid documentation url: ${docUrl}`);
+    }
+}
diff --git a/src/application/State/ApplicationState.ts b/src/application/State/ApplicationState.ts
index 4752179f..c0e4160b 100644
--- a/src/application/State/ApplicationState.ts
+++ b/src/application/State/ApplicationState.ts
@@ -6,7 +6,7 @@ import { IUserSelection } from './Selection/IUserSelection';
 import { AsyncLazy } from '../../infrastructure/Threading/AsyncLazy';
 import { Signal } from '../../infrastructure/Events/Signal';
 import { ICategory } from '../../domain/ICategory';
-import { ApplicationParser } from '../ApplicationParser';
+import { buildApplication } from '../Parser/ApplicationParser';
 import { IApplicationState } from './IApplicationState';
 import { Script } from '../../domain/Script';
 import { Application } from '../../domain/Application';
@@ -21,7 +21,7 @@ export class ApplicationState implements IApplicationState {
 
     /** Application instance with all scripts. */
     private static instance = new AsyncLazy<IApplicationState>(() => {
-        const app = ApplicationParser.buildApplication();
+        const app = buildApplication();
         const state = new ApplicationState(app.application, app.selectedScripts);
         return Promise.resolve(state);
     });