diff --git a/abschnitte/tests.py b/abschnitte/tests.py
index 7ce503c..93a0813 100644
--- a/abschnitte/tests.py
+++ b/abschnitte/tests.py
@@ -1,3 +1,377 @@
-from django.test import TestCase
+from unittest.mock import Mock, patch, MagicMock
+from django.test import TestCase, override_settings
+from abschnitte.models import AbschnittTyp, Textabschnitt
+from abschnitte.utils import render_textabschnitte, md_table_to_html
 
-# Create your tests here.
+
+class MockTextabschnitt:
+    """Mock object for Textabschnitt (since it's abstract)."""
+    def __init__(self, abschnitttyp, inhalt):
+        self.abschnitttyp = abschnitttyp
+        self.inhalt = inhalt
+
+
+class RenderTextabschnitteTestCase(TestCase):
+    """Test cases for render_textabschnitte function."""
+    
+    def setUp(self):
+        """Set up test fixtures."""
+        # Create mock AbschnittTyp objects
+        self.typ_text = Mock()
+        self.typ_text.abschnitttyp = "text"
+        
+        self.typ_liste_ungeordnet = Mock()
+        self.typ_liste_ungeordnet.abschnitttyp = "liste ungeordnet"
+        
+        self.typ_liste_geordnet = Mock()
+        self.typ_liste_geordnet.abschnitttyp = "liste geordnet"
+        
+        self.typ_tabelle = Mock()
+        self.typ_tabelle.abschnitttyp = "tabelle"
+        
+        self.typ_diagramm = Mock()
+        self.typ_diagramm.abschnitttyp = "diagramm"
+        
+        self.typ_code = Mock()
+        self.typ_code.abschnitttyp = "code"
+    
+    def test_render_basic_text(self):
+        """Test rendering basic text content."""
+        abschnitt = MockTextabschnitt(
+            abschnitttyp=self.typ_text,
+            inhalt="This is **bold** text with *italic*."
+        )
+        
+        result = render_textabschnitte([abschnitt])
+        
+        self.assertEqual(len(result), 1)
+        typ, html = result[0]
+        self.assertEqual(typ, "text")
+        self.assertIn("<strong>bold</strong>", html)
+        self.assertIn("<em>italic</em>", html)
+    
+    def test_render_unordered_list(self):
+        """Test rendering unordered list."""
+        abschnitt = MockTextabschnitt(
+            abschnitttyp=self.typ_liste_ungeordnet,
+            inhalt="Item 1\nItem 2\nItem 3"
+        )
+        
+        result = render_textabschnitte([abschnitt])
+        
+        self.assertEqual(len(result), 1)
+        typ, html = result[0]
+        self.assertEqual(typ, "liste ungeordnet")
+        self.assertIn("<ul>", html)
+        self.assertIn("<li>Item 1</li>", html)
+        self.assertIn("<li>Item 2</li>", html)
+        self.assertIn("<li>Item 3</li>", html)
+    
+    def test_render_ordered_list(self):
+        """Test rendering ordered list."""
+        abschnitt = MockTextabschnitt(
+            abschnitttyp=self.typ_liste_geordnet,
+            inhalt="First item\nSecond item\nThird item"
+        )
+        
+        result = render_textabschnitte([abschnitt])
+        
+        self.assertEqual(len(result), 1)
+        typ, html = result[0]
+        self.assertEqual(typ, "liste geordnet")
+        self.assertIn("<ol>", html)
+        self.assertIn("<li>First item</li>", html)
+    
+    def test_render_table(self):
+        """Test rendering markdown table."""
+        table_content = """| Header 1 | Header 2 |
+|----------|----------|
+| Cell 1   | Cell 2   |
+| Cell 3   | Cell 4   |"""
+        
+        abschnitt = MockTextabschnitt(
+            abschnitttyp=self.typ_tabelle,
+            inhalt=table_content
+        )
+        
+        result = render_textabschnitte([abschnitt])
+        
+        self.assertEqual(len(result), 1)
+        typ, html = result[0]
+        self.assertEqual(typ, "tabelle")
+        self.assertIn("<table", html)
+        self.assertIn("Header 1", html)
+        self.assertIn("Cell 1", html)
+        self.assertIn("table-bordered", html)
+    
+    @override_settings(MEDIA_URL='/media/')
+    @patch('abschnitte.utils.get_cached_diagram')
+    def test_render_diagram_success(self, mock_get_cached):
+        """Test rendering diagram with successful cache."""
+        mock_get_cached.return_value = 'diagram_cache/plantuml/abc123.svg'
+        
+        diagram_content = """plantuml
+@startuml
+A -> B
+@enduml"""
+        
+        abschnitt = MockTextabschnitt(
+            abschnitttyp=self.typ_diagramm,
+            inhalt=diagram_content
+        )
+        
+        result = render_textabschnitte([abschnitt])
+        
+        self.assertEqual(len(result), 1)
+        typ, html = result[0]
+        self.assertEqual(typ, "diagramm")
+        
+        # Verify diagram cache was called correctly
+        mock_get_cached.assert_called_once_with(
+            'plantuml',
+            '@startuml\nA -> B\n@enduml'
+        )
+        
+        # Verify HTML contains correct image tag
+        self.assertIn('<img', html)
+        self.assertIn('/media/diagram_cache/plantuml/abc123.svg', html)
+        self.assertIn('width="100%"', html)
+    
+    @patch('abschnitte.utils.get_cached_diagram')
+    def test_render_diagram_with_options(self, mock_get_cached):
+        """Test rendering diagram with custom options."""
+        mock_get_cached.return_value = 'diagram_cache/mermaid/def456.svg'
+        
+        diagram_content = """mermaid
+option:width="50%" height="300px"
+graph TD
+A --> B"""
+        
+        abschnitt = MockTextabschnitt(
+            abschnitttyp=self.typ_diagramm,
+            inhalt=diagram_content
+        )
+        
+        result = render_textabschnitte([abschnitt])
+        
+        typ, html = result[0]
+        
+        # Verify custom options are used
+        self.assertIn('width="50%"', html)
+        self.assertIn('height="300px"', html)
+        
+        # Verify diagram content doesn't include option line
+        call_args = mock_get_cached.call_args[0]
+        self.assertNotIn('option:', call_args[1])
+    
+    @patch('abschnitte.utils.get_cached_diagram')
+    def test_render_diagram_error(self, mock_get_cached):
+        """Test rendering diagram when caching fails."""
+        mock_get_cached.side_effect = Exception("Kroki server unavailable")
+        
+        diagram_content = """plantuml
+@startuml
+A -> B
+@enduml"""
+        
+        abschnitt = MockTextabschnitt(
+            abschnitttyp=self.typ_diagramm,
+            inhalt=diagram_content
+        )
+        
+        result = render_textabschnitte([abschnitt])
+        
+        typ, html = result[0]
+        
+        # Should show error message
+        self.assertIn('Error generating diagram', html)
+        self.assertIn('Kroki server unavailable', html)
+        self.assertIn('text-danger', html)
+    
+    def test_render_code(self):
+        """Test rendering code block."""
+        code_content = """def hello():
+    print("Hello, World!")"""
+        
+        abschnitt = MockTextabschnitt(
+            abschnitttyp=self.typ_code,
+            inhalt=code_content
+        )
+        
+        result = render_textabschnitte([abschnitt])
+        
+        typ, html = result[0]
+        self.assertEqual(typ, "code")
+        self.assertIn("<pre>", html)
+        self.assertIn("<code>", html)
+        self.assertIn("def hello():", html)
+    
+    def test_render_empty_content(self):
+        """Test rendering with empty or None content."""
+        abschnitt = MockTextabschnitt(
+            abschnitttyp=self.typ_text,
+            inhalt=None
+        )
+        
+        result = render_textabschnitte([abschnitt])
+        
+        self.assertEqual(len(result), 1)
+        typ, html = result[0]
+        self.assertEqual(typ, "text")
+        # Should not crash, should return empty or minimal HTML
+    
+    def test_render_multiple_abschnitte(self):
+        """Test rendering multiple sections."""
+        abschnitte = [
+            MockTextabschnitt(self.typ_text, "First paragraph"),
+            MockTextabschnitt(self.typ_liste_ungeordnet, "Item 1\nItem 2"),
+            MockTextabschnitt(self.typ_text, "Second paragraph"),
+        ]
+        
+        result = render_textabschnitte(abschnitte)
+        
+        self.assertEqual(len(result), 3)
+        self.assertEqual(result[0][0], "text")
+        self.assertEqual(result[1][0], "liste ungeordnet")
+        self.assertEqual(result[2][0], "text")
+    
+    def test_render_no_abschnitttyp(self):
+        """Test rendering when abschnitttyp is None."""
+        abschnitt = MockTextabschnitt(
+            abschnitttyp=None,
+            inhalt="Some content"
+        )
+        
+        result = render_textabschnitte([abschnitt])
+        
+        self.assertEqual(len(result), 1)
+        typ, html = result[0]
+        self.assertEqual(typ, "")
+        # Should still render as markdown
+        self.assertIn("Some content", html)
+
+
+class MdTableToHtmlTestCase(TestCase):
+    """Test cases for md_table_to_html function."""
+    
+    def test_basic_table(self):
+        """Test converting basic markdown table to HTML."""
+        md = """| Name | Age |
+|------|-----|
+| Alice | 30 |
+| Bob | 25 |"""
+        
+        html = md_table_to_html(md)
+        
+        self.assertIn('<table', html)
+        self.assertIn('table-bordered', html)
+        self.assertIn('table-hover', html)
+        self.assertIn('<thead>', html)
+        self.assertIn('<tbody>', html)
+        self.assertIn('<th>Name</th>', html)
+        self.assertIn('<th>Age</th>', html)
+        self.assertIn('<td>Alice</td>', html)
+        self.assertIn('<td>30</td>', html)
+    
+    def test_table_with_spaces(self):
+        """Test table with various spacing."""
+        md = """|  Name  |  Age  |
+|--------|-------|
+|  Alice |   30  |
+|   Bob  |  25   |"""
+        
+        html = md_table_to_html(md)
+        
+        # Spaces should be trimmed
+        self.assertIn('<th>Name</th>', html)
+        self.assertIn('<th>Age</th>', html)
+        self.assertIn('<td>Alice</td>', html)
+    
+    def test_table_no_outer_pipes(self):
+        """Test table without outer pipe characters."""
+        md = """Name | Age
+-----|-----
+Alice | 30
+Bob | 25"""
+        
+        html = md_table_to_html(md)
+        
+        self.assertIn('<th>Name</th>', html)
+        self.assertIn('<td>Alice</td>', html)
+    
+    def test_table_insufficient_rows(self):
+        """Test error handling for malformed table."""
+        md = """| Name |
+|------|"""
+        
+        with self.assertRaises(ValueError) as context:
+            md_table_to_html(md)
+        
+        self.assertIn("at least header + separator", str(context.exception))
+    
+    def test_table_with_empty_cells(self):
+        """Test table with empty cells."""
+        md = """| Name | Age |
+|------|-----|
+| Alice |  |
+|  | 25 |"""
+        
+        html = md_table_to_html(md)
+        
+        self.assertIn('<td>Alice</td>', html)
+        self.assertIn('<td></td>', html)
+        self.assertIn('<td>25</td>', html)
+    
+    def test_table_three_columns(self):
+        """Test table with more columns."""
+        md = """| First | Middle | Last |
+|-------|--------|------|
+| John  | Q      | Doe  |"""
+        
+        html = md_table_to_html(md)
+        
+        self.assertIn('<th>First</th>', html)
+        self.assertIn('<th>Middle</th>', html)
+        self.assertIn('<th>Last</th>', html)
+        self.assertIn('<td>John</td>', html)
+        self.assertIn('<td>Q</td>', html)
+        self.assertIn('<td>Doe</td>', html)
+
+
+class RenderIntegrationTestCase(TestCase):
+    """Integration tests for rendering pipeline."""
+    
+    @patch('abschnitte.utils.get_cached_diagram')
+    def test_mixed_content_rendering(self, mock_get_cached):
+        """Test rendering a mix of different content types."""
+        mock_get_cached.return_value = 'diagram_cache/test.svg'
+        
+        # Create various types of content
+        typ_text = Mock(abschnitttyp="text")
+        typ_liste = Mock(abschnitttyp="liste ungeordnet")
+        typ_diagram = Mock(abschnitttyp="diagramm")
+        
+        abschnitte = [
+            MockTextabschnitt(typ_text, "Introduction paragraph"),
+            MockTextabschnitt(typ_liste, "Point 1\nPoint 2\nPoint 3"),
+            MockTextabschnitt(typ_diagram, "plantuml\n@startuml\nA -> B\n@enduml"),
+            MockTextabschnitt(typ_text, "Conclusion"),
+        ]
+        
+        result = render_textabschnitte(abschnitte)
+        
+        # Should have 4 results
+        self.assertEqual(len(result), 4)
+        
+        # Verify each type was rendered correctly
+        self.assertEqual(result[0][0], "text")
+        self.assertIn("Introduction", result[0][1])
+        
+        self.assertEqual(result[1][0], "liste ungeordnet")
+        self.assertIn("<ul>", result[1][1])
+        
+        self.assertEqual(result[2][0], "diagramm")
+        self.assertIn("<img", result[2][1])
+        
+        self.assertEqual(result[3][0], "text")
+        self.assertIn("Conclusion", result[3][1])