diff --git a/.build/langium-cli.d.ts b/.build/langium-cli.d.ts
deleted file mode 100644
index a1cfe25f89..0000000000
--- a/.build/langium-cli.d.ts
+++ /dev/null
@@ -1,9 +0,0 @@
-declare module 'langium-cli' {
-  export interface GenerateOptions {
-    file?: string;
-    mode?: 'development' | 'production';
-    watch?: boolean;
-  }
-
-  export function generate(options: GenerateOptions): Promise<boolean>;
-}
diff --git a/docs/intro/getting-started.md b/docs/intro/getting-started.md
index c2c663d39a..73001ee07d 100644
--- a/docs/intro/getting-started.md
+++ b/docs/intro/getting-started.md
@@ -246,18 +246,18 @@ In this example, the `mermaidAPI` is being called through the `CDN`:
   <body>
     Here is one mermaid diagram:
     <pre class="mermaid">
-            graph TD 
-            A[Client] --> B[Load Balancer] 
-            B --> C[Server1] 
+            graph TD
+            A[Client] --> B[Load Balancer]
+            B --> C[Server1]
             B --> D[Server2]
     </pre>
 
     And here is another:
     <pre class="mermaid">
-            graph TD 
+            graph TD
             A[Client] -->|tcp_123| B
-            B(Load Balancer) 
-            B -->|tcp_456| C[Server1] 
+            B(Load Balancer)
+            B -->|tcp_456| C[Server1]
             B -->|tcp_456| D[Server2]
     </pre>
 
@@ -278,15 +278,15 @@ In this example, `mermaid.js` is referenced in `src` as a separate JavaScript fi
   </head>
   <body>
     <pre class="mermaid">
-            graph LR 
-            A --- B 
-            B-->C[fa:fa-ban forbidden] 
+            graph LR
+            A --- B
+            B-->C[fa:fa-ban forbidden]
             B-->D(fa:fa-spinner);
     </pre>
     <pre class="mermaid">
-            graph TD 
-            A[Client] --> B[Load Balancer] 
-            B --> C[Server1] 
+            graph TD
+            A[Client] --> B[Load Balancer]
+            B --> C[Server1]
             B --> D[Server2]
     </pre>
     <script type="module">
diff --git a/netlify.toml b/netlify.toml
index 2853f4c82d..50129d3ca3 100644
--- a/netlify.toml
+++ b/netlify.toml
@@ -7,9 +7,9 @@
   base = ""
 
   # Directory that contains the deploy-ready HTML files and
-  # assets generated by the build. This is an absolute path relative 
+  # assets generated by the build. This is an absolute path relative
   # to the base directory, which is the root by default (/).
-  # This sample publishes the directory located at the absolute 
+  # This sample publishes the directory located at the absolute
   # path "root/project/build-output"
 
   publish = "mermaid-live-editor/docs"
diff --git a/packages/mermaid/src/diagrams/pie/parser/pie.jison b/packages/mermaid/src/diagrams/pie/parser/pie.jison
deleted file mode 100644
index d1f516e755..0000000000
--- a/packages/mermaid/src/diagrams/pie/parser/pie.jison
+++ /dev/null
@@ -1,74 +0,0 @@
-/** mermaid
- *  https://knsv.github.io/mermaid
- *  (c) 2015 Knut Sveidqvist
- *  MIT license.
- */
-%lex
-%options case-insensitive
-
-%x string
-%x title
-%x acc_title
-%x acc_descr
-%x acc_descr_multiline
-%%
-\%\%(?!\{)[^\n]*                                                /* skip comments */
-[^\}]\%\%[^\n]*                                                 /* skip comments */{ /*console.log('');*/ }
-[\n\r]+                                                         return 'NEWLINE';
-\%\%[^\n]*                                                      /* do nothing */
-[\s]+ 		                                                      /* ignore */
-title                                                           { this.begin("title");return 'title'; }
-<title>(?!\n|;|#)*[^\n]*                                        { this.popState(); return "title_value"; }
-
-accTitle\s*":"\s*                                               { this.begin("acc_title");return 'acc_title'; }
-<acc_title>(?!\n|;|#)*[^\n]*                                    { this.popState(); return "acc_title_value"; }
-accDescr\s*":"\s*                                               { this.begin("acc_descr");return 'acc_descr'; }
-<acc_descr>(?!\n|;|#)*[^\n]*                                    { this.popState(); return "acc_descr_value"; }
-accDescr\s*"{"\s*                                { this.begin("acc_descr_multiline");}
-<acc_descr_multiline>[\}]                       { this.popState(); }
-<acc_descr_multiline>[^\}]*                     return "acc_descr_multiline_value";
-["]                                                             { this.begin("string"); }
-<string>["]                                                     { this.popState(); }
-<string>[^"]*                                                   { return "txt"; }
-"pie"		                                                        return 'PIE';
-"showData"                                                      return 'showData';
-":"[\s]*[\d]+(?:\.[\d]+)?                                       return "value";
-<<EOF>>                                                         return 'EOF';
-
-/lex
-
-%start start
-
-%% /* language grammar */
-
-start
-  : eol start
-	| PIE document
-  | PIE showData document {yy.setShowData(true);}
-	;
-
-document
-	: /* empty */
-	| document line
-	;
-
-line
-	: statement eol { $$ = $1 }
-	;
-
-statement
-  :
-	| txt value          { yy.addSection($1,yy.cleanupValue($2)); }
-	| title title_value  { $$=$2.trim();yy.setDiagramTitle($$); }
-  | acc_title acc_title_value  { $$=$2.trim();yy.setAccTitle($$); }
-  | acc_descr acc_descr_value  { $$=$2.trim();yy.setAccDescription($$); }
-  | acc_descr_multiline_value { $$=$1.trim();yy.setAccDescription($$); }  | section {yy.addSection($1.substr(8));$$=$1.substr(8);}
-	;
-
-eol
-  : NEWLINE
-  | ';'
-  | EOF
-  ;
-
-%%
diff --git a/packages/mermaid/src/diagrams/pie/pie.spec.ts b/packages/mermaid/src/diagrams/pie/pie.spec.ts
index 47a9a95f55..f68e80efdb 100644
--- a/packages/mermaid/src/diagrams/pie/pie.spec.ts
+++ b/packages/mermaid/src/diagrams/pie/pie.spec.ts
@@ -1,5 +1,4 @@
-// @ts-ignore: JISON doesn't support types
-import { parser } from './parser/pie.jison';
+import { parser } from './pieParser.js';
 import { DEFAULT_PIE_DB, db } from './pieDb.js';
 import { setConfig } from '../../diagram-api/diagramAPI.js';
 
@@ -8,17 +7,11 @@ setConfig({
 });
 
 describe('pie', () => {
-  beforeAll(() => {
-    parser.yy = db;
-  });
-
-  beforeEach(() => {
-    parser.yy.clear();
-  });
+  beforeEach(() => db.clear());
 
   describe('parse', () => {
-    it('should handle very simple pie', () => {
-      parser.parse(`pie
+    it('should handle very simple pie', async () => {
+      await parser.parse(`pie
       "ash": 100
       `);
 
@@ -26,8 +19,8 @@ describe('pie', () => {
       expect(sections['ash']).toBe(100);
     });
 
-    it('should handle simple pie', () => {
-      parser.parse(`pie
+    it('should handle simple pie', async () => {
+      await parser.parse(`pie
       "ash" : 60
       "bat" : 40
       `);
@@ -37,8 +30,8 @@ describe('pie', () => {
       expect(sections['bat']).toBe(40);
     });
 
-    it('should handle simple pie with showData', () => {
-      parser.parse(`pie showData
+    it('should handle simple pie with showData', async () => {
+      await parser.parse(`pie showData
       "ash" : 60
       "bat" : 40
       `);
@@ -50,8 +43,8 @@ describe('pie', () => {
       expect(sections['bat']).toBe(40);
     });
 
-    it('should handle simple pie with comments', () => {
-      parser.parse(`pie
+    it('should handle simple pie with comments', async () => {
+      await parser.parse(`pie
       %% comments
       "ash" : 60
       "bat" : 40
@@ -62,8 +55,8 @@ describe('pie', () => {
       expect(sections['bat']).toBe(40);
     });
 
-    it('should handle simple pie with a title', () => {
-      parser.parse(`pie title a 60/40 pie
+    it('should handle simple pie with a title', async () => {
+      await parser.parse(`pie title a 60/40 pie
       "ash" : 60
       "bat" : 40
       `);
@@ -75,8 +68,8 @@ describe('pie', () => {
       expect(sections['bat']).toBe(40);
     });
 
-    it('should handle simple pie with an acc title (accTitle)', () => {
-      parser.parse(`pie title a neat chart
+    it('should handle simple pie with an acc title (accTitle)', async () => {
+      await parser.parse(`pie title a neat chart
       accTitle: a neat acc title
       "ash" : 60
       "bat" : 40
@@ -91,8 +84,8 @@ describe('pie', () => {
       expect(sections['bat']).toBe(40);
     });
 
-    it('should handle simple pie with an acc description (accDescr)', () => {
-      parser.parse(`pie title a neat chart
+    it('should handle simple pie with an acc description (accDescr)', async () => {
+      await parser.parse(`pie title a neat chart
       accDescr: a neat description
       "ash" : 60
       "bat" : 40
@@ -107,8 +100,8 @@ describe('pie', () => {
       expect(sections['bat']).toBe(40);
     });
 
-    it('should handle simple pie with a multiline acc description (accDescr)', () => {
-      parser.parse(`pie title a neat chart
+    it('should handle simple pie with a multiline acc description (accDescr)', async () => {
+      await parser.parse(`pie title a neat chart
       accDescr {
         a neat description
         on multiple lines
@@ -126,8 +119,8 @@ describe('pie', () => {
       expect(sections['bat']).toBe(40);
     });
 
-    it('should handle simple pie with positive decimal', () => {
-      parser.parse(`pie
+    it('should handle simple pie with positive decimal', async () => {
+      await parser.parse(`pie
       "ash" : 60.67
       "bat" : 40
       `);
@@ -138,12 +131,12 @@ describe('pie', () => {
     });
 
     it('should handle simple pie with negative decimal', () => {
-      expect(() => {
-        parser.parse(`pie
+      expect(async () => {
+        await parser.parse(`pie
         "ash" : -60.67
         "bat" : 40.12
         `);
-      }).toThrowError();
+      }).rejects.toThrowError();
     });
   });
 
diff --git a/packages/mermaid/src/diagrams/pie/pieDb.ts b/packages/mermaid/src/diagrams/pie/pieDb.ts
index e2eebea543..1501aad1f4 100644
--- a/packages/mermaid/src/diagrams/pie/pieDb.ts
+++ b/packages/mermaid/src/diagrams/pie/pieDb.ts
@@ -1,6 +1,4 @@
 import { log } from '../../logger.js';
-import { getConfig as commonGetConfig } from '../../diagram-api/diagramAPI.js';
-import { sanitizeText } from '../common/common.js';
 import {
   setAccTitle,
   getAccTitle,
@@ -10,7 +8,7 @@ import {
   setAccDescription,
   clear as commonClear,
 } from '../common/commonDb.js';
-import type { PieFields, PieDB, Sections } from './pieTypes.js';
+import type { PieFields, PieDB, Sections, D3Section } from './pieTypes.js';
 import type { RequiredDeep } from 'type-fest';
 import type { PieDiagramConfig } from '../../config.type.js';
 import DEFAULT_CONFIG from '../../defaultConfig.js';
@@ -35,8 +33,7 @@ const clear = (): void => {
   commonClear();
 };
 
-const addSection = (label: string, value: number): void => {
-  label = sanitizeText(label, commonGetConfig());
+const addSection = ({ label, value }: D3Section): void => {
   if (sections[label] === undefined) {
     sections[label] = value;
     log.debug(`added new section: ${label}, with value: ${value}`);
@@ -45,13 +42,6 @@ const addSection = (label: string, value: number): void => {
 
 const getSections = (): Sections => sections;
 
-const cleanupValue = (value: string): number => {
-  if (value.substring(0, 1) === ':') {
-    value = value.substring(1).trim();
-  }
-  return Number(value.trim());
-};
-
 const setShowData = (toggle: boolean): void => {
   showData = toggle;
 };
@@ -71,7 +61,6 @@ export const db: PieDB = {
 
   addSection,
   getSections,
-  cleanupValue,
   setShowData,
   getShowData,
 };
diff --git a/packages/mermaid/src/diagrams/pie/pieDiagram.ts b/packages/mermaid/src/diagrams/pie/pieDiagram.ts
index f0aa19b419..eb990e8769 100644
--- a/packages/mermaid/src/diagrams/pie/pieDiagram.ts
+++ b/packages/mermaid/src/diagrams/pie/pieDiagram.ts
@@ -1,6 +1,5 @@
 import type { DiagramDefinition } from '../../diagram-api/types.js';
-// @ts-ignore: JISON doesn't support types
-import parser from './parser/pie.jison';
+import { parser } from './pieParser.js';
 import { db } from './pieDb.js';
 import styles from './pieStyles.js';
 import { renderer } from './pieRenderer.js';
diff --git a/packages/mermaid/src/diagrams/pie/pieParser.ts b/packages/mermaid/src/diagrams/pie/pieParser.ts
new file mode 100644
index 0000000000..fbdc603d60
--- /dev/null
+++ b/packages/mermaid/src/diagrams/pie/pieParser.ts
@@ -0,0 +1,21 @@
+import type { Pie } from '@mermaid-js/parser';
+import { parse } from '@mermaid-js/parser';
+import { log } from '../../logger.js';
+import type { ParserDefinition } from '../../diagram-api/types.js';
+import { populateCommonDb } from '../common/populateCommonDb.js';
+import type { PieDB } from './pieTypes.js';
+import { db } from './pieDb.js';
+
+const populateDb = (ast: Pie, db: PieDB) => {
+  populateCommonDb(ast, db);
+  db.setShowData(ast.showData);
+  ast.sections.map(db.addSection);
+};
+
+export const parser: ParserDefinition = {
+  parse: async (input: string): Promise<void> => {
+    const ast: Pie = await parse('pie', input);
+    log.debug(ast);
+    populateDb(ast, db);
+  },
+};
diff --git a/packages/mermaid/src/diagrams/pie/pieRenderer.ts b/packages/mermaid/src/diagrams/pie/pieRenderer.ts
index a24bcb532b..fb386863b0 100644
--- a/packages/mermaid/src/diagrams/pie/pieRenderer.ts
+++ b/packages/mermaid/src/diagrams/pie/pieRenderer.ts
@@ -5,24 +5,24 @@ import { configureSvgSize } from '../../setupGraphViewbox.js';
 import { getConfig } from '../../diagram-api/diagramAPI.js';
 import { cleanAndMerge, parseFontSize } from '../../utils.js';
 import type { DrawDefinition, Group, SVG } from '../../diagram-api/types.js';
-import type { D3Sections, PieDB, Sections } from './pieTypes.js';
+import type { D3Section, PieDB, Sections } from './pieTypes.js';
 import type { MermaidConfig, PieDiagramConfig } from '../../config.type.js';
 import { selectSvgElement } from '../../rendering-util/selectSvgElement.js';
 
-const createPieArcs = (sections: Sections): d3.PieArcDatum<D3Sections>[] => {
+const createPieArcs = (sections: Sections): d3.PieArcDatum<D3Section>[] => {
   // Compute the position of each group on the pie:
-  const pieData: D3Sections[] = Object.entries(sections)
-    .map((element: [string, number]): D3Sections => {
+  const pieData: D3Section[] = Object.entries(sections)
+    .map((element: [string, number]): D3Section => {
       return {
         label: element[0],
         value: element[1],
       };
     })
-    .sort((a: D3Sections, b: D3Sections): number => {
+    .sort((a: D3Section, b: D3Section): number => {
       return b.value - a.value;
     });
-  const pie: d3.Pie<unknown, D3Sections> = d3pie<D3Sections>().value(
-    (d3Section: D3Sections): number => d3Section.value
+  const pie: d3.Pie<unknown, D3Section> = d3pie<D3Section>().value(
+    (d3Section: D3Section): number => d3Section.value
   );
   return pie(pieData);
 };
@@ -47,7 +47,6 @@ export const draw: DrawDefinition = (text, id, _version, diagObj) => {
   const pieWidth: number = height;
   const svg: SVG = selectSvgElement(id);
   const group: Group = svg.append('g');
-  const sections: Sections = db.getSections();
   group.attr('transform', 'translate(' + pieWidth / 2 + ',' + height / 2 + ')');
 
   const { themeVariables } = globalConfig;
@@ -57,13 +56,11 @@ export const draw: DrawDefinition = (text, id, _version, diagObj) => {
   const textPosition: number = pieConfig.textPosition;
   const radius: number = Math.min(pieWidth, height) / 2 - MARGIN;
   // Shape helper to build arcs:
-  const arcGenerator: d3.Arc<unknown, d3.PieArcDatum<D3Sections>> = arc<
-    d3.PieArcDatum<D3Sections>
-  >()
+  const arcGenerator: d3.Arc<unknown, d3.PieArcDatum<D3Section>> = arc<d3.PieArcDatum<D3Section>>()
     .innerRadius(0)
     .outerRadius(radius);
-  const labelArcGenerator: d3.Arc<unknown, d3.PieArcDatum<D3Sections>> = arc<
-    d3.PieArcDatum<D3Sections>
+  const labelArcGenerator: d3.Arc<unknown, d3.PieArcDatum<D3Section>> = arc<
+    d3.PieArcDatum<D3Section>
   >()
     .innerRadius(radius * textPosition)
     .outerRadius(radius * textPosition);
@@ -75,7 +72,8 @@ export const draw: DrawDefinition = (text, id, _version, diagObj) => {
     .attr('r', radius + outerStrokeWidth / 2)
     .attr('class', 'pieOuterCircle');
 
-  const arcs: d3.PieArcDatum<D3Sections>[] = createPieArcs(sections);
+  const sections: Sections = db.getSections();
+  const arcs: d3.PieArcDatum<D3Section>[] = createPieArcs(sections);
 
   const myGeneratedColors = [
     themeVariables.pie1,
@@ -101,7 +99,7 @@ export const draw: DrawDefinition = (text, id, _version, diagObj) => {
     .enter()
     .append('path')
     .attr('d', arcGenerator)
-    .attr('fill', (datum: d3.PieArcDatum<D3Sections>) => {
+    .attr('fill', (datum: d3.PieArcDatum<D3Section>) => {
       return color(datum.data.label);
     })
     .attr('class', 'pieCircle');
@@ -117,10 +115,10 @@ export const draw: DrawDefinition = (text, id, _version, diagObj) => {
     .data(arcs)
     .enter()
     .append('text')
-    .text((datum: d3.PieArcDatum<D3Sections>): string => {
+    .text((datum: d3.PieArcDatum<D3Section>): string => {
       return ((datum.data.value / sum) * 100).toFixed(0) + '%';
     })
-    .attr('transform', (datum: d3.PieArcDatum<D3Sections>): string => {
+    .attr('transform', (datum: d3.PieArcDatum<D3Section>): string => {
       return 'translate(' + labelArcGenerator.centroid(datum) + ')';
     })
     .style('text-anchor', 'middle')
@@ -160,7 +158,7 @@ export const draw: DrawDefinition = (text, id, _version, diagObj) => {
     .append('text')
     .attr('x', LEGEND_RECT_SIZE + LEGEND_SPACING)
     .attr('y', LEGEND_RECT_SIZE - LEGEND_SPACING)
-    .text((datum: d3.PieArcDatum<D3Sections>): string => {
+    .text((datum: d3.PieArcDatum<D3Section>): string => {
       const { label, value } = datum.data;
       if (db.getShowData()) {
         return `${label} [${value}]`;
diff --git a/packages/mermaid/src/diagrams/pie/pieTypes.ts b/packages/mermaid/src/diagrams/pie/pieTypes.ts
index 6ba3ab92e5..067d8cbbf6 100644
--- a/packages/mermaid/src/diagrams/pie/pieTypes.ts
+++ b/packages/mermaid/src/diagrams/pie/pieTypes.ts
@@ -36,7 +36,7 @@ export interface PieStyleOptions {
 
 export type Sections = Record<string, number>;
 
-export interface D3Sections {
+export interface D3Section {
   label: string;
   value: number;
 }
@@ -55,9 +55,8 @@ export interface PieDB extends DiagramDB {
   getAccDescription: () => string;
 
   // diagram db
-  addSection: (label: string, value: number) => void;
+  addSection: ({ label, value }: D3Section) => void;
   getSections: () => Sections;
-  cleanupValue: (value: string) => number;
   setShowData: (toggle: boolean) => void;
   getShowData: () => boolean;
 }
diff --git a/packages/mermaid/src/docs/intro/getting-started.md b/packages/mermaid/src/docs/intro/getting-started.md
index 1a97fcfbfd..2bfa36bb74 100644
--- a/packages/mermaid/src/docs/intro/getting-started.md
+++ b/packages/mermaid/src/docs/intro/getting-started.md
@@ -239,18 +239,18 @@ In this example, the `mermaidAPI` is being called through the `CDN`:
   <body>
     Here is one mermaid diagram:
     <pre class="mermaid">
-            graph TD 
-            A[Client] --> B[Load Balancer] 
-            B --> C[Server1] 
+            graph TD
+            A[Client] --> B[Load Balancer]
+            B --> C[Server1]
             B --> D[Server2]
     </pre>
 
     And here is another:
     <pre class="mermaid">
-            graph TD 
+            graph TD
             A[Client] -->|tcp_123| B
-            B(Load Balancer) 
-            B -->|tcp_456| C[Server1] 
+            B(Load Balancer)
+            B -->|tcp_456| C[Server1]
             B -->|tcp_456| D[Server2]
     </pre>
 
@@ -271,15 +271,15 @@ In this example, `mermaid.js` is referenced in `src` as a separate JavaScript fi
   </head>
   <body>
     <pre class="mermaid">
-            graph LR 
-            A --- B 
-            B-->C[fa:fa-ban forbidden] 
+            graph LR
+            A --- B
+            B-->C[fa:fa-ban forbidden]
             B-->D(fa:fa-spinner);
     </pre>
     <pre class="mermaid">
-            graph TD 
-            A[Client] --> B[Load Balancer] 
-            B --> C[Server1] 
+            graph TD
+            A[Client] --> B[Load Balancer]
+            B --> C[Server1]
             B --> D[Server2]
     </pre>
     <script type="module">
diff --git a/packages/parser/langium-config.json b/packages/parser/langium-config.json
index 6daa551c17..c750f049d5 100644
--- a/packages/parser/langium-config.json
+++ b/packages/parser/langium-config.json
@@ -10,6 +10,11 @@
       "id": "packet",
       "grammar": "src/language/packet/packet.langium",
       "fileExtensions": [".mmd", ".mermaid"]
+    },
+    {
+      "id": "pie",
+      "grammar": "src/language/pie/pie.langium",
+      "fileExtensions": [".mmd", ".mermaid"]
     }
   ],
   "mode": "production",
diff --git a/packages/parser/package.json b/packages/parser/package.json
index 7192996209..aa9c08f420 100644
--- a/packages/parser/package.json
+++ b/packages/parser/package.json
@@ -12,7 +12,7 @@
   "type": "module",
   "exports": {
     ".": {
-      "import": "./dist/mermaid-parser.esm.mjs",
+      "import": "./dist/mermaid-parser.core.mjs",
       "types": "./dist/src/index.d.ts"
     }
   },
@@ -34,10 +34,10 @@
     "ast"
   ],
   "dependencies": {
-    "langium": "2.0.1"
+    "langium": "2.1.2"
   },
   "devDependencies": {
-    "langium-cli": "2.0.1"
+    "chevrotain": "^11.0.3"
   },
   "files": [
     "dist/"
diff --git a/packages/parser/src/index.ts b/packages/parser/src/index.ts
index c72b4fcb6e..75f0cb3d83 100644
--- a/packages/parser/src/index.ts
+++ b/packages/parser/src/index.ts
@@ -1,8 +1,7 @@
 import type { AstNode } from 'langium';
 
-export type { Info, Packet } from './language/index.js';
-export { MermaidParseError, parse } from './parse.js';
-export type { DiagramAST } from './parse.js';
+export * from './language/index.js';
+export * from './parse.js';
 
 /**
  * Exclude/omit all `AstNode` attributes recursively.
diff --git a/packages/parser/src/language/chevrotainWrapper.ts b/packages/parser/src/language/chevrotainWrapper.ts
deleted file mode 100644
index bde44a22ef..0000000000
--- a/packages/parser/src/language/chevrotainWrapper.ts
+++ /dev/null
@@ -1,51 +0,0 @@
-/* eslint-disable @typescript-eslint/no-explicit-any */
-
-type CustomPatternMatcherReturn = [string] & { payload?: any };
-
-export type CustomPatternMatcherFunc = (
-  text: string,
-  offset: number,
-  tokens: IToken[],
-  groups: {
-    [groupName: string]: IToken[];
-  }
-) => CustomPatternMatcherReturn | RegExpExecArray | null;
-
-interface ICustomPattern {
-  exec: CustomPatternMatcherFunc;
-}
-
-type TokenPattern = RegExp | string | CustomPatternMatcherFunc | ICustomPattern;
-
-export interface IToken {
-  image: string;
-  startOffset: number;
-  startLine?: number;
-  startColumn?: number;
-  endOffset?: number;
-  endLine?: number;
-  endColumn?: number;
-  isInsertedInRecovery?: boolean;
-  tokenTypeIdx: number;
-  tokenType: TokenType;
-  payload?: any;
-}
-
-export interface TokenType {
-  name: string;
-  GROUP?: string;
-  PATTERN?: TokenPattern;
-  LABEL?: string;
-  LONGER_ALT?: TokenType | TokenType[];
-  POP_MODE?: boolean;
-  PUSH_MODE?: string;
-  LINE_BREAKS?: boolean;
-  CATEGORIES?: TokenType[];
-  tokenTypeIdx?: number;
-  categoryMatches?: number[];
-  categoryMatchesMap?: {
-    [tokType: number]: boolean;
-  };
-  isParent?: boolean;
-  START_CHARS_HINT?: (string | number)[];
-}
diff --git a/packages/parser/src/language/common/common.langium b/packages/parser/src/language/common/common.langium
index f1a695e49f..7989de1931 100644
--- a/packages/parser/src/language/common/common.langium
+++ b/packages/parser/src/language/common/common.langium
@@ -5,15 +5,19 @@ interface Common {
 }
 
 fragment TitleAndAccessibilities:
-  ((accDescr=ACC_DESCR | accTitle=ACC_TITLE | title=TITLE) NEWLINE+)+
+  ((accDescr=ACC_DESCR | accTitle=ACC_TITLE | title=TITLE) EOL)+
+;
+
+fragment EOL returns string:
+  NEWLINE+ | EOF
 ;
 
 terminal NEWLINE: /\r?\n/;
-terminal ACC_DESCR: /accDescr([\t ]*:[^\n\r]*(?=%%)|\s*{[^}]*})|accDescr([\t ]*:[^\n\r]*|\s*{[^}]*})/;
-terminal ACC_TITLE: /accTitle[\t ]*:[^\n\r]*(?=%%)|accTitle[\t ]*:[^\n\r]*/;
-terminal TITLE: /title([\t ][^\n\r]*|)(?=%%)|title([\t ][^\n\r]*|)/;
+terminal ACC_DESCR: /[\t ]*accDescr(?:[\t ]*:([^\n\r]*?(?=%%)|[^\n\r]*)|\s*{([^}]*)})/;
+terminal ACC_TITLE: /[\t ]*accTitle[\t ]*:(?:[^\n\r]*?(?=%%)|[^\n\r]*)/;
+terminal TITLE: /[\t ]*title(?:[\t ][^\n\r]*?(?=%%)|[\t ][^\n\r]*|)/;
 
 hidden terminal WHITESPACE: /[\t ]+/;
-hidden terminal YAML: /---[\t ]*\r?\n[\S\s]*?---[\t ]*(?!.)/;
-hidden terminal DIRECTIVE: /[\t ]*%%{[\S\s]*?}%%\s*/;
+hidden terminal YAML: /---[\t ]*\r?\n(?:[\S\s]*?\r?\n)?---(?:\r?\n|(?!\S))/;
+hidden terminal DIRECTIVE: /[\t ]*%%{[\S\s]*?}%%(?:\r?\n|(?!\S))/;
 hidden terminal SINGLE_LINE_COMMENT: /[\t ]*%%[^\n\r]*/;
diff --git a/packages/parser/src/language/common/index.ts b/packages/parser/src/language/common/index.ts
index 2ab5ebcd40..92b69489ef 100644
--- a/packages/parser/src/language/common/index.ts
+++ b/packages/parser/src/language/common/index.ts
@@ -1,3 +1,2 @@
-export * from './lexer.js';
 export * from './tokenBuilder.js';
-export { MermaidValueConverter } from './valueConverter.js';
+export * from './valueConverter.js';
diff --git a/packages/parser/src/language/common/lexer.ts b/packages/parser/src/language/common/lexer.ts
deleted file mode 100644
index e4f1272b2f..0000000000
--- a/packages/parser/src/language/common/lexer.ts
+++ /dev/null
@@ -1,8 +0,0 @@
-import type { LexerResult } from 'langium';
-import { DefaultLexer } from 'langium';
-
-export class CommonLexer extends DefaultLexer {
-  public override tokenize(text: string): LexerResult {
-    return super.tokenize(text + '\n');
-  }
-}
diff --git a/packages/parser/src/language/common/matcher.ts b/packages/parser/src/language/common/matcher.ts
index 36c9cbe920..cc9d607e1f 100644
--- a/packages/parser/src/language/common/matcher.ts
+++ b/packages/parser/src/language/common/matcher.ts
@@ -1,14 +1,14 @@
 /**
- * Matches single and multiline accessible description
+ * Matches single and multi line accessible description
  */
-export const accessibilityDescrRegex = /accDescr(?:[\t ]*:[\t ]*([^\n\r]*)|\s*{([^}]*)})/;
+export const accessibilityDescrRegex = /accDescr(?:[\t ]*:([^\n\r]*)|\s*{([^}]*)})/;
 
 /**
  * Matches single line accessible title
  */
-export const accessibilityTitleRegex = /accTitle[\t ]*:[\t ]*([^\n\r]*)/;
+export const accessibilityTitleRegex = /accTitle[\t ]*:([^\n\r]*)/;
 
 /**
  * Matches a single line title
  */
-export const titleRegex = /title([\t ]+([^\n\r]*)|)/;
+export const titleRegex = /title([\t ][^\n\r]*|)/;
diff --git a/packages/parser/src/language/common/tokenBuilder.ts b/packages/parser/src/language/common/tokenBuilder.ts
index 5a94d5d594..f997634545 100644
--- a/packages/parser/src/language/common/tokenBuilder.ts
+++ b/packages/parser/src/language/common/tokenBuilder.ts
@@ -1,9 +1,9 @@
 import type { GrammarAST, Stream, TokenBuilderOptions } from 'langium';
-import type { TokenType } from '../chevrotainWrapper.js';
+import type { TokenType } from 'chevrotain';
 
 import { DefaultTokenBuilder } from 'langium';
 
-export abstract class MermaidTokenBuilder extends DefaultTokenBuilder {
+export abstract class AbstractMermaidTokenBuilder extends DefaultTokenBuilder {
   private keywords: Set<string>;
 
   public constructor(keywords: string[]) {
@@ -20,9 +20,11 @@ export abstract class MermaidTokenBuilder extends DefaultTokenBuilder {
     // to restrict users, they mustn't have any non-whitespace characters after the keyword.
     tokenTypes.forEach((tokenType: TokenType): void => {
       if (this.keywords.has(tokenType.name) && tokenType.PATTERN !== undefined) {
-        tokenType.PATTERN = new RegExp(tokenType.PATTERN.toString() + '(?!\\S)');
+        tokenType.PATTERN = new RegExp(tokenType.PATTERN.toString() + '(?:(?=%%)|(?!\\S))');
       }
     });
     return tokenTypes;
   }
 }
+
+export class CommonTokenBuilder extends AbstractMermaidTokenBuilder {}
diff --git a/packages/parser/src/language/common/valueConverter.ts b/packages/parser/src/language/common/valueConverter.ts
index bc31ba7144..624cc67a5e 100644
--- a/packages/parser/src/language/common/valueConverter.ts
+++ b/packages/parser/src/language/common/valueConverter.ts
@@ -10,7 +10,7 @@ const rulesRegexes: Record<string, RegExp> = {
   TITLE: titleRegex,
 };
 
-export abstract class MermaidValueConverter extends DefaultValueConverter {
+export abstract class AbstractMermaidValueConverter extends DefaultValueConverter {
   /**
    * A method contains convert logic to be used by class.
    *
@@ -71,8 +71,8 @@ export abstract class MermaidValueConverter extends DefaultValueConverter {
   }
 }
 
-export class CommonValueConverter extends MermaidValueConverter {
-  protected runCustomConverter(
+export class CommonValueConverter extends AbstractMermaidValueConverter {
+  protected override runCustomConverter(
     _rule: GrammarAST.AbstractRule,
     _input: string,
     _cstNode: CstNode
diff --git a/packages/parser/src/language/index.ts b/packages/parser/src/language/index.ts
index a1c3dfd8d3..9f1d92ba8a 100644
--- a/packages/parser/src/language/index.ts
+++ b/packages/parser/src/language/index.ts
@@ -1,7 +1,25 @@
-export * from './generated/ast.js';
-export * from './generated/grammar.js';
-export * from './generated/module.js';
+export {
+  Info,
+  MermaidAstType,
+  Packet,
+  PacketBlock,
+  Pie,
+  PieSection,
+  isCommon,
+  isInfo,
+  isPacket,
+  isPacketBlock,
+  isPie,
+  isPieSection,
+} from './generated/ast.js';
+export {
+  InfoGeneratedModule,
+  MermaidGeneratedSharedModule,
+  PacketGeneratedModule,
+  PieGeneratedModule,
+} from './generated/module.js';
 
 export * from './common/index.js';
 export * from './info/index.js';
 export * from './packet/index.js';
+export * from './pie/index.js';
diff --git a/packages/parser/src/language/info/module.ts b/packages/parser/src/language/info/module.ts
index 5d6b74e108..17f1fb4eb1 100644
--- a/packages/parser/src/language/info/module.ts
+++ b/packages/parser/src/language/info/module.ts
@@ -7,8 +7,7 @@ import type {
 } from 'langium';
 import { EmptyFileSystem, createDefaultModule, createDefaultSharedModule, inject } from 'langium';
 
-import { CommonLexer } from '../common/lexer.js';
-import { CommonValueConverter } from '../common/valueConverter.js';
+import { CommonValueConverter } from '../common/index.js';
 import { InfoGeneratedModule, MermaidGeneratedSharedModule } from '../generated/module.js';
 import { InfoTokenBuilder } from './tokenBuilder.js';
 
@@ -17,7 +16,6 @@ import { InfoTokenBuilder } from './tokenBuilder.js';
  */
 type InfoAddedServices = {
   parser: {
-    Lexer: CommonLexer;
     TokenBuilder: InfoTokenBuilder;
     ValueConverter: CommonValueConverter;
   };
@@ -34,7 +32,6 @@ export type InfoServices = LangiumServices & InfoAddedServices;
  */
 export const InfoModule: Module<InfoServices, PartialLangiumServices & InfoAddedServices> = {
   parser: {
-    Lexer: (services: InfoServices) => new CommonLexer(services),
     TokenBuilder: () => new InfoTokenBuilder(),
     ValueConverter: () => new CommonValueConverter(),
   },
diff --git a/packages/parser/src/language/info/tokenBuilder.ts b/packages/parser/src/language/info/tokenBuilder.ts
index 311d372e46..69ad0e689d 100644
--- a/packages/parser/src/language/info/tokenBuilder.ts
+++ b/packages/parser/src/language/info/tokenBuilder.ts
@@ -1,6 +1,6 @@
-import { MermaidTokenBuilder } from '../common/index.js';
+import { AbstractMermaidTokenBuilder } from '../common/index.js';
 
-export class InfoTokenBuilder extends MermaidTokenBuilder {
+export class InfoTokenBuilder extends AbstractMermaidTokenBuilder {
   public constructor() {
     super(['info', 'showInfo']);
   }
diff --git a/packages/parser/src/language/packet/module.ts b/packages/parser/src/language/packet/module.ts
index 183ec0ff83..460d5e5358 100644
--- a/packages/parser/src/language/packet/module.ts
+++ b/packages/parser/src/language/packet/module.ts
@@ -6,7 +6,6 @@ import type {
   PartialLangiumServices,
 } from 'langium';
 import { EmptyFileSystem, createDefaultModule, createDefaultSharedModule, inject } from 'langium';
-import { CommonLexer } from '../common/lexer.js';
 import { CommonValueConverter } from '../common/valueConverter.js';
 import { MermaidGeneratedSharedModule, PacketGeneratedModule } from '../generated/module.js';
 import { PacketTokenBuilder } from './tokenBuilder.js';
@@ -16,7 +15,6 @@ import { PacketTokenBuilder } from './tokenBuilder.js';
  */
 type PacketAddedServices = {
   parser: {
-    Lexer: CommonLexer;
     TokenBuilder: PacketTokenBuilder;
     ValueConverter: CommonValueConverter;
   };
@@ -33,7 +31,6 @@ export type PacketServices = LangiumServices & PacketAddedServices;
  */
 export const PacketModule: Module<PacketServices, PartialLangiumServices & PacketAddedServices> = {
   parser: {
-    Lexer: (services: PacketServices) => new CommonLexer(services),
     TokenBuilder: () => new PacketTokenBuilder(),
     ValueConverter: () => new CommonValueConverter(),
   },
diff --git a/packages/parser/src/language/packet/packet.langium b/packages/parser/src/language/packet/packet.langium
index dce1c1ef86..ad30f8df20 100644
--- a/packages/parser/src/language/packet/packet.langium
+++ b/packages/parser/src/language/packet/packet.langium
@@ -4,15 +4,15 @@ import "../common/common";
 entry Packet:
   NEWLINE*
   "packet-beta"
-  (  
-    NEWLINE* TitleAndAccessibilities blocks+=PacketBlock*  
-    | NEWLINE+ blocks+=PacketBlock+  
-    | NEWLINE*  
+  (
+    NEWLINE* TitleAndAccessibilities blocks+=PacketBlock*
+    | NEWLINE+ blocks+=PacketBlock+
+    | NEWLINE*
   )
 ;
 
 PacketBlock:
-  start=INT('-' end=INT)? ':' label=STRING NEWLINE+
+  start=INT('-' end=INT)? ':' label=STRING EOL
 ;
 
 terminal INT returns number: /0|[1-9][0-9]*/;
diff --git a/packages/parser/src/language/packet/tokenBuilder.ts b/packages/parser/src/language/packet/tokenBuilder.ts
index 3317f85496..accba5675a 100644
--- a/packages/parser/src/language/packet/tokenBuilder.ts
+++ b/packages/parser/src/language/packet/tokenBuilder.ts
@@ -1,6 +1,6 @@
-import { MermaidTokenBuilder } from '../common/index.js';
+import { AbstractMermaidTokenBuilder } from '../common/index.js';
 
-export class PacketTokenBuilder extends MermaidTokenBuilder {
+export class PacketTokenBuilder extends AbstractMermaidTokenBuilder {
   public constructor() {
     super(['packet-beta']);
   }
diff --git a/packages/parser/src/language/pie/index.ts b/packages/parser/src/language/pie/index.ts
new file mode 100644
index 0000000000..fd3c604b08
--- /dev/null
+++ b/packages/parser/src/language/pie/index.ts
@@ -0,0 +1 @@
+export * from './module.js';
diff --git a/packages/parser/src/language/pie/module.ts b/packages/parser/src/language/pie/module.ts
new file mode 100644
index 0000000000..8777abc866
--- /dev/null
+++ b/packages/parser/src/language/pie/module.ts
@@ -0,0 +1,65 @@
+import type {
+  DefaultSharedModuleContext,
+  LangiumServices,
+  LangiumSharedServices,
+  Module,
+  PartialLangiumServices,
+} from 'langium';
+import { EmptyFileSystem, createDefaultModule, createDefaultSharedModule, inject } from 'langium';
+
+import { MermaidGeneratedSharedModule, PieGeneratedModule } from '../generated/module.js';
+import { PieTokenBuilder } from './tokenBuilder.js';
+import { PieValueConverter } from './valueConverter.js';
+
+/**
+ * Declaration of `Pie` services.
+ */
+type PieAddedServices = {
+  parser: {
+    TokenBuilder: PieTokenBuilder;
+    ValueConverter: PieValueConverter;
+  };
+};
+
+/**
+ * Union of Langium default services and `Pie` services.
+ */
+export type PieServices = LangiumServices & PieAddedServices;
+
+/**
+ * Dependency injection module that overrides Langium default services and
+ * contributes the declared `Pie` services.
+ */
+export const PieModule: Module<PieServices, PartialLangiumServices & PieAddedServices> = {
+  parser: {
+    TokenBuilder: () => new PieTokenBuilder(),
+    ValueConverter: () => new PieValueConverter(),
+  },
+};
+
+/**
+ * Create the full set of services required by Langium.
+ *
+ * First inject the shared services by merging two modules:
+ *  - Langium default shared services
+ *  - Services generated by langium-cli
+ *
+ * Then inject the language-specific services by merging three modules:
+ *  - Langium default language-specific services
+ *  - Services generated by langium-cli
+ *  - Services specified in this file
+ * @param context - Optional module context with the LSP connection
+ * @returns An object wrapping the shared services and the language-specific services
+ */
+export function createPieServices(context: DefaultSharedModuleContext = EmptyFileSystem): {
+  shared: LangiumSharedServices;
+  Pie: PieServices;
+} {
+  const shared: LangiumSharedServices = inject(
+    createDefaultSharedModule(context),
+    MermaidGeneratedSharedModule
+  );
+  const Pie: PieServices = inject(createDefaultModule({ shared }), PieGeneratedModule, PieModule);
+  shared.ServiceRegistry.register(Pie);
+  return { shared, Pie };
+}
diff --git a/packages/parser/src/language/pie/pie.langium b/packages/parser/src/language/pie/pie.langium
new file mode 100644
index 0000000000..2bbf967e1d
--- /dev/null
+++ b/packages/parser/src/language/pie/pie.langium
@@ -0,0 +1,19 @@
+grammar Pie
+import "../common/common";
+
+entry Pie:
+  NEWLINE*
+  "pie" showData?="showData"?
+  (
+    NEWLINE* TitleAndAccessibilities sections+=PieSection*
+    | NEWLINE+ sections+=PieSection+
+    | NEWLINE*
+  )
+;
+
+PieSection:
+  label=PIE_SECTION_LABEL ":" value=PIE_SECTION_VALUE EOL
+;
+
+terminal PIE_SECTION_LABEL: /"[^"]+"/;
+terminal PIE_SECTION_VALUE returns number: /(0|[1-9][0-9]*)(\.[0-9]+)?/;
diff --git a/packages/parser/src/language/pie/tokenBuilder.ts b/packages/parser/src/language/pie/tokenBuilder.ts
new file mode 100644
index 0000000000..85aecf96a0
--- /dev/null
+++ b/packages/parser/src/language/pie/tokenBuilder.ts
@@ -0,0 +1,7 @@
+import { AbstractMermaidTokenBuilder } from '../common/index.js';
+
+export class PieTokenBuilder extends AbstractMermaidTokenBuilder {
+  public constructor() {
+    super(['pie', 'showData']);
+  }
+}
diff --git a/packages/parser/src/language/pie/valueConverter.ts b/packages/parser/src/language/pie/valueConverter.ts
new file mode 100644
index 0000000000..b0ae18c0ba
--- /dev/null
+++ b/packages/parser/src/language/pie/valueConverter.ts
@@ -0,0 +1,17 @@
+import type { CstNode, GrammarAST, ValueType } from 'langium';
+
+import { AbstractMermaidValueConverter } from '../common/index.js';
+
+export class PieValueConverter extends AbstractMermaidValueConverter {
+  protected runCustomConverter(
+    rule: GrammarAST.AbstractRule,
+    input: string,
+    // eslint-disable-next-line @typescript-eslint/no-unused-vars
+    _cstNode: CstNode
+  ): ValueType | undefined {
+    if (rule.name !== 'PIE_SECTION_LABEL') {
+      return undefined;
+    }
+    return input.replace(/"/g, '').trim();
+  }
+}
diff --git a/packages/parser/src/parse.ts b/packages/parser/src/parse.ts
index 855fc272bc..577a1cea6f 100644
--- a/packages/parser/src/parse.ts
+++ b/packages/parser/src/parse.ts
@@ -1,10 +1,10 @@
 import type { LangiumParser, ParseResult } from 'langium';
-import type { Info, Packet } from './index.js';
 
-export type DiagramAST = Info | Packet;
+import type { Info, Packet, Pie } from './index.js';
 
-const parsers: Record<string, LangiumParser> = {};
+export type DiagramAST = Info | Packet | Pie;
 
+const parsers: Record<string, LangiumParser> = {};
 const initializers = {
   info: async () => {
     const { createInfoServices } = await import('./language/info/index.js');
@@ -16,9 +16,16 @@ const initializers = {
     const parser = createPacketServices().Packet.parser.LangiumParser;
     parsers['packet'] = parser;
   },
+  pie: async () => {
+    const { createPieServices } = await import('./language/pie/index.js');
+    const parser = createPieServices().Pie.parser.LangiumParser;
+    parsers['pie'] = parser;
+  },
 } as const;
+
 export async function parse(diagramType: 'info', text: string): Promise<Info>;
 export async function parse(diagramType: 'packet', text: string): Promise<Packet>;
+export async function parse(diagramType: 'pie', text: string): Promise<Pie>;
 export async function parse<T extends DiagramAST>(
   diagramType: keyof typeof initializers,
   text: string
diff --git a/packages/parser/tests/info.test.ts b/packages/parser/tests/info.test.ts
index df86ae16c9..09fc79c9af 100644
--- a/packages/parser/tests/info.test.ts
+++ b/packages/parser/tests/info.test.ts
@@ -1,26 +1,9 @@
 import { describe, expect, it } from 'vitest';
-import type { LangiumParser, ParseResult } from 'langium';
 
-import type { InfoServices } from '../src/language/index.js';
-import { Info, createInfoServices } from '../src/language/index.js';
-import { noErrorsOrAlternatives } from './test-util.js';
-
-const services: InfoServices = createInfoServices().Info;
-const parser: LangiumParser = services.parser.LangiumParser;
-function createInfoTestServices(): {
-  services: InfoServices;
-  parse: (input: string) => ParseResult<Info>;
-} {
-  const parse = (input: string) => {
-    return parser.parse<Info>(input);
-  };
-
-  return { services, parse };
-}
+import { Info } from '../src/language/index.js';
+import { expectNoErrorsOrAlternatives, infoParse as parse } from './test-util.js';
 
 describe('info', () => {
-  const { parse } = createInfoTestServices();
-
   it.each([
     `info`,
     `
@@ -32,26 +15,34 @@ describe('info', () => {
     `,
   ])('should handle empty info', (context: string) => {
     const result = parse(context);
-    noErrorsOrAlternatives(result);
-
+    expectNoErrorsOrAlternatives(result);
     expect(result.value.$type).toBe(Info);
   });
 
   it.each([
     `info showInfo`,
+    `info showInfo
+    `,
     `
     info showInfo`,
     `info
+    showInfo`,
+    `info
     showInfo
     `,
     `
     info
     showInfo
     `,
+    `
+    info
+    showInfo`,
+    `
+    info showInfo
+    `,
   ])('should handle showInfo', (context: string) => {
     const result = parse(context);
-    noErrorsOrAlternatives(result);
-
+    expectNoErrorsOrAlternatives(result);
     expect(result.value.$type).toBe(Info);
   });
 });
diff --git a/packages/parser/tests/pie.test.ts b/packages/parser/tests/pie.test.ts
new file mode 100644
index 0000000000..04f83c933b
--- /dev/null
+++ b/packages/parser/tests/pie.test.ts
@@ -0,0 +1,229 @@
+import { describe, expect, it } from 'vitest';
+
+import { Pie } from '../src/language/index.js';
+import { expectNoErrorsOrAlternatives, pieParse as parse } from './test-util.js';
+
+describe('pie', () => {
+  it.each([
+    `pie`,
+    `  pie  `,
+    `\tpie\t`,
+    `
+    \tpie
+    `,
+  ])('should handle regular pie', (context: string) => {
+    const result = parse(context);
+    expectNoErrorsOrAlternatives(result);
+    expect(result.value.$type).toBe(Pie);
+  });
+
+  it.each([
+    `pie showData`,
+    `  pie  showData  `,
+    `\tpie\tshowData\t`,
+    `
+    pie\tshowData
+    `,
+  ])('should handle regular showData', (context: string) => {
+    const result = parse(context);
+    expectNoErrorsOrAlternatives(result);
+    expect(result.value.$type).toBe(Pie);
+
+    const { showData } = result.value;
+    expect(showData).toBeTruthy();
+  });
+
+  it.each([
+    `pie title sample title`,
+    `  pie  title sample title  `,
+    `\tpie\ttitle sample title\t`,
+    `pie
+    \ttitle sample title
+    `,
+  ])('should handle regular pie + title in same line', (context: string) => {
+    const result = parse(context);
+    expectNoErrorsOrAlternatives(result);
+    expect(result.value.$type).toBe(Pie);
+
+    const { title } = result.value;
+    expect(title).toBe('sample title');
+  });
+
+  it.each([
+    `pie
+    title sample title`,
+    `pie
+    title sample title
+    `,
+    `pie
+    title sample title`,
+    `pie
+    title sample title
+    `,
+  ])('should handle regular pie + title in different line', (context: string) => {
+    const result = parse(context);
+    expectNoErrorsOrAlternatives(result);
+    expect(result.value.$type).toBe(Pie);
+
+    const { title } = result.value;
+    expect(title).toBe('sample title');
+  });
+
+  it.each([
+    `pie showData title sample title`,
+    `pie showData title sample title
+    `,
+  ])('should handle regular pie + showData + title', (context: string) => {
+    const result = parse(context);
+    expectNoErrorsOrAlternatives(result);
+    expect(result.value.$type).toBe(Pie);
+
+    const { showData, title } = result.value;
+    expect(showData).toBeTruthy();
+    expect(title).toBe('sample title');
+  });
+
+  it.each([
+    `pie showData
+    title sample title`,
+    `pie showData
+    title sample title
+    `,
+    `pie showData
+    title sample title`,
+    `pie showData
+    title sample title
+    `,
+  ])('should handle regular showData + title in different line', (context: string) => {
+    const result = parse(context);
+    expectNoErrorsOrAlternatives(result);
+    expect(result.value.$type).toBe(Pie);
+
+    const { showData, title } = result.value;
+    expect(showData).toBeTruthy();
+    expect(title).toBe('sample title');
+  });
+
+  describe('sections', () => {
+    describe('normal', () => {
+      it.each([
+        `pie
+        "GitHub":100
+        "GitLab":50`,
+        `pie
+        "GitHub"   :   100
+        "GitLab"   :   50`,
+        `pie
+        "GitHub"\t:\t100
+        "GitLab"\t:\t50`,
+        `pie
+        \t"GitHub" \t : \t 100
+        \t"GitLab" \t : \t  50
+        `,
+      ])('should handle regular secions', (context: string) => {
+        const result = parse(context);
+        expectNoErrorsOrAlternatives(result);
+        expect(result.value.$type).toBe(Pie);
+
+        const { sections } = result.value;
+        expect(sections[0].label).toBe('GitHub');
+        expect(sections[0].value).toBe(100);
+
+        expect(sections[1].label).toBe('GitLab');
+        expect(sections[1].value).toBe(50);
+      });
+
+      it('should handle sections with showData', () => {
+        const context = `pie showData
+        "GitHub": 100
+        "GitLab": 50`;
+        const result = parse(context);
+        expectNoErrorsOrAlternatives(result);
+        expect(result.value.$type).toBe(Pie);
+
+        const { showData, sections } = result.value;
+        expect(showData).toBeTruthy();
+
+        expect(sections[0].label).toBe('GitHub');
+        expect(sections[0].value).toBe(100);
+
+        expect(sections[1].label).toBe('GitLab');
+        expect(sections[1].value).toBe(50);
+      });
+
+      it('should handle sections with title', () => {
+        const context = `pie title sample wow
+        "GitHub": 100
+        "GitLab": 50`;
+        const result = parse(context);
+        expectNoErrorsOrAlternatives(result);
+        expect(result.value.$type).toBe(Pie);
+
+        const { title, sections } = result.value;
+        expect(title).toBe('sample wow');
+
+        expect(sections[0].label).toBe('GitHub');
+        expect(sections[0].value).toBe(100);
+
+        expect(sections[1].label).toBe('GitLab');
+        expect(sections[1].value).toBe(50);
+      });
+
+      it('should handle sections with accTitle', () => {
+        const context = `pie accTitle: sample wow
+        "GitHub": 100
+        "GitLab": 50`;
+        const result = parse(context);
+        expectNoErrorsOrAlternatives(result);
+        expect(result.value.$type).toBe(Pie);
+
+        const { accTitle, sections } = result.value;
+        expect(accTitle).toBe('sample wow');
+
+        expect(sections[0].label).toBe('GitHub');
+        expect(sections[0].value).toBe(100);
+
+        expect(sections[1].label).toBe('GitLab');
+        expect(sections[1].value).toBe(50);
+      });
+
+      it('should handle sections with single line accDescr', () => {
+        const context = `pie accDescr: sample wow
+        "GitHub": 100
+        "GitLab": 50`;
+        const result = parse(context);
+        expectNoErrorsOrAlternatives(result);
+        expect(result.value.$type).toBe(Pie);
+
+        const { accDescr, sections } = result.value;
+        expect(accDescr).toBe('sample wow');
+
+        expect(sections[0].label).toBe('GitHub');
+        expect(sections[0].value).toBe(100);
+
+        expect(sections[1].label).toBe('GitLab');
+        expect(sections[1].value).toBe(50);
+      });
+
+      it('should handle sections with multi line accDescr', () => {
+        const context = `pie accDescr {
+            sample wow
+        }
+        "GitHub": 100
+        "GitLab": 50`;
+        const result = parse(context);
+        expectNoErrorsOrAlternatives(result);
+        expect(result.value.$type).toBe(Pie);
+
+        const { accDescr, sections } = result.value;
+        expect(accDescr).toBe('sample wow');
+
+        expect(sections[0].label).toBe('GitHub');
+        expect(sections[0].value).toBe(100);
+
+        expect(sections[1].label).toBe('GitLab');
+        expect(sections[1].value).toBe(50);
+      });
+    });
+  });
+});
diff --git a/packages/parser/tests/test-util.ts b/packages/parser/tests/test-util.ts
index 514e29cde5..9bdec348a1 100644
--- a/packages/parser/tests/test-util.ts
+++ b/packages/parser/tests/test-util.ts
@@ -1,5 +1,7 @@
+import type { LangiumParser, ParseResult } from 'langium';
 import { expect, vi } from 'vitest';
-import type { ParseResult } from 'langium';
+import type { Info, InfoServices, Pie, PieServices } from '../src/language/index.js';
+import { createInfoServices, createPieServices } from '../src/language/index.js';
 
 const consoleMock = vi.spyOn(console, 'log').mockImplementation(() => undefined);
 
@@ -9,10 +11,32 @@ const consoleMock = vi.spyOn(console, 'log').mockImplementation(() => undefined)
  *
  * @param result - the result `parse` function.
  */
-export function noErrorsOrAlternatives(result: ParseResult) {
+export function expectNoErrorsOrAlternatives(result: ParseResult) {
   expect(result.lexerErrors).toHaveLength(0);
   expect(result.parserErrors).toHaveLength(0);
 
   expect(consoleMock).not.toHaveBeenCalled();
   consoleMock.mockReset();
 }
+
+const infoServices: InfoServices = createInfoServices().Info;
+const infoParser: LangiumParser = infoServices.parser.LangiumParser;
+export function createInfoTestServices() {
+  const parse = (input: string) => {
+    return infoParser.parse<Info>(input);
+  };
+
+  return { services: infoServices, parse };
+}
+export const infoParse = createInfoTestServices().parse;
+
+const pieServices: PieServices = createPieServices().Pie;
+const pieParser: LangiumParser = pieServices.parser.LangiumParser;
+export function createPieTestServices() {
+  const parse = (input: string) => {
+    return pieParser.parse<Pie>(input);
+  };
+
+  return { services: pieServices, parse };
+}
+export const pieParse = createPieTestServices().parse;
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 1fa9920735..15e066ed04 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -496,12 +496,12 @@ importers:
   packages/parser:
     dependencies:
       langium:
-        specifier: 2.0.1
-        version: 2.0.1
+        specifier: 2.1.2
+        version: 2.1.2
     devDependencies:
-      langium-cli:
-        specifier: 2.0.1
-        version: 2.0.1
+      chevrotain:
+        specifier: ^11.0.3
+        version: 11.0.3
 
   tests/webpack:
     dependencies:
@@ -11968,20 +11968,6 @@ packages:
     engines: {node: '>=12'}
     dev: true
 
-  /langium-cli@2.0.1:
-    resolution: {integrity: sha512-dPPaHimIoCgELED4tvRGdU3i26tjWuyVwexXgPtTtTzp1MBdGCBLppLADXHkL8yFVdWM/PWlCq06YyqAT4eV3A==}
-    engines: {node: '>=16.0.0'}
-    hasBin: true
-    dependencies:
-      chalk: 5.3.0
-      commander: 10.0.1
-      fs-extra: 11.1.1
-      jsonschema: 1.4.1
-      langium: 2.0.1
-      langium-railroad: 2.0.0
-      lodash: 4.17.21
-    dev: true
-
   /langium-cli@2.1.0:
     resolution: {integrity: sha512-Gbj4CvfAc1gP/6ihxikd2Je95j1FWjXZu8bbji2/t2vQ6kEP+vs9Fx7kSGOM0AbU/hjZfy6E35bJPOdwsiyqTA==}
     engines: {node: '>=16.0.0'}
@@ -11991,37 +11977,20 @@ packages:
       commander: 11.0.0
       fs-extra: 11.1.1
       jsonschema: 1.4.1
-      langium: 2.1.3
+      langium: 2.1.2
       langium-railroad: 2.1.0
       lodash: 4.17.21
     dev: true
 
-  /langium-railroad@2.0.0:
-    resolution: {integrity: sha512-g6y8vPh4i7ll/Q4D9aFrjk4UgtkuzkE6WGfiTHJHTFlDwHoiKrPSIIBZO4wjEb3XUF9P5vIt7aRjerTy7Jgm0g==}
-    dependencies:
-      langium: 2.0.1
-      railroad-diagrams: 1.0.0
-    dev: true
-
   /langium-railroad@2.1.0:
     resolution: {integrity: sha512-2IeAIUSTQzbDjNnJA+0ql8tyN/mhCSN4FS50Mo9LOtLj523qUEBwHflDmCiOGZzW9iZdni6NXJgh8nLqjhTlDw==}
     dependencies:
-      langium: 2.1.3
+      langium: 2.1.2
       railroad-diagrams: 1.0.0
     dev: true
 
-  /langium@2.0.1:
-    resolution: {integrity: sha512-EGi8NNN/5zxcUL//sA4kqpV9YVOZfDngwkkSxsZ/zfx4Wjdg9von71rWIMCV6kW1M40kPOKF6e8oMTyWeX92fg==}
-    engines: {node: '>=16.0.0'}
-    dependencies:
-      chevrotain: 11.0.3
-      chevrotain-allstar: 0.3.1(chevrotain@11.0.3)
-      vscode-languageserver: 8.0.2
-      vscode-languageserver-textdocument: 1.0.8
-      vscode-uri: 3.0.7
-
-  /langium@2.1.3:
-    resolution: {integrity: sha512-/WN1xHoNBg0mi1Jp9ydMFSHIv8Jhq7K+0stNVURdoG4NgZx4/06AfNeeixmmU8X842wBl9gFZJP5O93Ge5Oasw==}
+  /langium@2.1.2:
+    resolution: {integrity: sha512-1NDUmhm111xs6NLh1DzQ9YPrOhL6JqJryY9igPIGrG0AbKKGmGf3fahAiY1MUChwIYSec6Fvoj+igwKzvGXQog==}
     engines: {node: '>=16.0.0'}
     dependencies:
       chevrotain: 11.0.3
@@ -12029,7 +11998,6 @@ packages:
       vscode-languageserver: 9.0.1
       vscode-languageserver-textdocument: 1.0.11
       vscode-uri: 3.0.8
-    dev: true
 
   /layout-base@1.0.2:
     resolution: {integrity: sha512-8h2oVEZNktL4BH2JCOI90iD1yXwL6iNW7KcCKT2QZgQJR2vbqDsldCTPRU9NifTCqHZci57XvQQ15YTu+sTYPg==}
@@ -16502,37 +16470,22 @@ packages:
       vscode-uri: 3.0.7
     dev: true
 
-  /vscode-jsonrpc@8.0.2:
-    resolution: {integrity: sha512-RY7HwI/ydoC1Wwg4gJ3y6LpU9FJRZAUnTYMXthqhFXXu77ErDd/xkREpGuk4MyYkk4a+XDWAMqe0S3KkelYQEQ==}
-    engines: {node: '>=14.0.0'}
-
   /vscode-jsonrpc@8.2.0:
     resolution: {integrity: sha512-C+r0eKJUIfiDIfwJhria30+TYWPtuHJXHtI7J0YlOmKAo7ogxP20T0zxB7HZQIFhIyvoBPwWskjxrvAtfjyZfA==}
     engines: {node: '>=14.0.0'}
-    dev: true
-
-  /vscode-languageserver-protocol@3.17.2:
-    resolution: {integrity: sha512-8kYisQ3z/SQ2kyjlNeQxbkkTNmVFoQCqkmGrzLH6A9ecPlgTbp3wDTnUNqaUxYr4vlAcloxx8zwy7G5WdguYNg==}
-    dependencies:
-      vscode-jsonrpc: 8.0.2
-      vscode-languageserver-types: 3.17.2
 
   /vscode-languageserver-protocol@3.17.5:
     resolution: {integrity: sha512-mb1bvRJN8SVznADSGWM9u/b07H7Ecg0I3OgXDuLdn307rl/J3A9YD6/eYOssqhecL27hK1IPZAsaqh00i/Jljg==}
     dependencies:
       vscode-jsonrpc: 8.2.0
       vscode-languageserver-types: 3.17.5
-    dev: true
 
   /vscode-languageserver-textdocument@1.0.11:
     resolution: {integrity: sha512-X+8T3GoiwTVlJbicx/sIAF+yuJAqz8VvwJyoMVhwEMoEKE/fkDmrqUgDMyBECcM2A2frVZIUj5HI/ErRXCfOeA==}
-    dev: true
 
   /vscode-languageserver-textdocument@1.0.8:
     resolution: {integrity: sha512-1bonkGqQs5/fxGT5UchTgjGVnfysL0O8v1AYMBjqTbWQTFn721zaPGDYFkOKtfDgFiSgXM3KwaG3FMGfW4Ed9Q==}
-
-  /vscode-languageserver-types@3.17.2:
-    resolution: {integrity: sha512-zHhCWatviizPIq9B7Vh9uvrH6x3sK8itC84HkamnBWoDFJtzBf7SWlpLCZUit72b3os45h6RWQNC9xHRDF8dRA==}
+    dev: true
 
   /vscode-languageserver-types@3.17.3:
     resolution: {integrity: sha512-SYU4z1dL0PyIMd4Vj8YOqFvHu7Hz/enbWtpfnVbJHU4Nd1YNYx8u0ennumc6h48GQNeOLxmwySmnADouT/AuZA==}
@@ -16540,20 +16493,12 @@ packages:
 
   /vscode-languageserver-types@3.17.5:
     resolution: {integrity: sha512-Ld1VelNuX9pdF39h2Hgaeb5hEZM2Z3jUrrMgWQAu82jMtZp7p3vJT3BzToKtZI7NgQssZje5o0zryOrhQvzQAg==}
-    dev: true
-
-  /vscode-languageserver@8.0.2:
-    resolution: {integrity: sha512-bpEt2ggPxKzsAOZlXmCJ50bV7VrxwCS5BI4+egUmure/oI/t4OlFzi/YNtVvY24A2UDOZAgwFGgnZPwqSJubkA==}
-    hasBin: true
-    dependencies:
-      vscode-languageserver-protocol: 3.17.2
 
   /vscode-languageserver@9.0.1:
     resolution: {integrity: sha512-woByF3PDpkHFUreUa7Hos7+pUWdeWMXRd26+ZX2A8cFx6v/JPTtd4/uN0/jB6XQHYaOlHbio03NTHCqrgG5n7g==}
     hasBin: true
     dependencies:
       vscode-languageserver-protocol: 3.17.5
-    dev: true
 
   /vscode-nls@5.2.0:
     resolution: {integrity: sha512-RAaHx7B14ZU04EU31pT+rKz2/zSl7xMsfIZuo8pd+KZO6PXtQmpevpq3vxvWNcrGbdmhM/rr5Uw5Mz+NBfhVng==}
@@ -16569,10 +16514,10 @@ packages:
 
   /vscode-uri@3.0.7:
     resolution: {integrity: sha512-eOpPHogvorZRobNqJGhapa0JdwaxpjVvyBp0QIUMRMSf8ZAlqOdEquKuRmw9Qwu0qXtJIWqFtMkmvJjUZmMjVA==}
+    dev: true
 
   /vscode-uri@3.0.8:
     resolution: {integrity: sha512-AyFQ0EVmsOZOlAnxoFOGOq1SQDWAB7C6aqMGS23svWAllfOaxbuFvcT8D1i8z3Gyn8fraVeZNNmN6e9bxxXkKw==}
-    dev: true
 
   /vue-demi@0.13.11(vue@3.4.15):
     resolution: {integrity: sha512-IR8HoEEGM65YY3ZJYAjMlKygDQn25D5ajNFNoKh9RSDMQtlzCxtfQjdQgv9jjK+m3377SsJXY8ysq8kLCZL25A==}
