diff --git a/CHANGELOG.md b/CHANGELOG.md
index c060f91d..1d86095c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,12 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 ## [Unreleased]
+### Added
+- Added syntax rule for `None` literal
+
+### Fixed
+- Profile header rule now strictly requires full semver version in version field, as the spec defines
+- Condition to add SingleLineCommentTrivia to termina tokens in sublexer
 
 ## [2.0.0] - 2022-11-08
 ### Added
diff --git a/README.md b/README.md
index 80d8fcde..843a976d 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # Parser
 
-![GitHub Workflow Status](https://img.shields.io/github/workflow/status/superfaceai/parser/CI)
+[![GitHub Workflow Status](https://img.shields.io/github/actions/workflow/status/superfaceai/parser/main.yml?branch=dev)](https://github.com/superfaceai/parser/actions/workflows/main.yml)
 ![NPM](https://img.shields.io/npm/v/@superfaceai/parser)
 [![NPM](https://img.shields.io/npm/l/@superfaceai/parser)](LICENSE)
 ![TypeScript](https://img.shields.io/badge/%3C%2F%3E-Typescript-blue)
diff --git a/package.json b/package.json
index 6be2a338..85d96a71 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@superfaceai/parser",
-  "version": "2.0.0",
+  "version": "2.1.0-rc.0",
   "description": "Level 5 autonomous, self-driving API client, https://superface.ai",
   "repository": "https://github.com/superfaceai/parser.git",
   "source": "lib/index.js",
@@ -43,7 +43,7 @@
     "ts-jest": "^27.1.3"
   },
   "dependencies": {
-    "@superfaceai/ast": "^1.2.0",
+    "@superfaceai/ast": "^1.3.0",
     "@types/debug": "^4.1.5",
     "debug": "^4.3.3",
     "typescript": "^4"
diff --git a/src/interpreter/example-validator.test.ts b/src/interpreter/example-validator.test.ts
index 13e4746f..d98d59b2 100644
--- a/src/interpreter/example-validator.test.ts
+++ b/src/interpreter/example-validator.test.ts
@@ -99,5 +99,25 @@ describe('ExampleValidator', () => {
         'ComlinkPrimitiveLiteral - Wrong Structure: expected [boolean | number], but got "string"',
       ]);
     });
+
+    it('none', () => {
+      const profileAst = parseProfileFromSource(
+        `usecase Test {
+              result {
+                  f1 string!
+              }
+  
+              example fail {
+                  result {
+                      f1 = None
+                  }
+              }
+          }`
+      );
+
+      expect(profileAst).not.toBeValidExample([
+        'ComlinkNoneLiteral - Wrong Structure: expected string!, but got None',
+      ]);
+    });
   });
 });
diff --git a/src/interpreter/example-validator.ts b/src/interpreter/example-validator.ts
index 1a5e8036..a329d8c2 100644
--- a/src/interpreter/example-validator.ts
+++ b/src/interpreter/example-validator.ts
@@ -2,6 +2,7 @@ import {
   ComlinkAssignmentNode,
   ComlinkListLiteralNode,
   ComlinkLiteralNode,
+  ComlinkNoneLiteralNode,
   ComlinkObjectLiteralNode,
   ComlinkPrimitiveLiteralNode,
   EnumDefinitionNode,
@@ -40,6 +41,7 @@ import {
 } from '.';
 import {
   validateListLiteral,
+  validateNoneLiteral,
   validateObjectLiteral,
   validatePrimitiveLiteral,
 } from './utils';
@@ -102,6 +104,8 @@ export class ExampleValidator implements ProfileAstVisitor {
         return this.visitComlinkObjectLiteralNode(node);
       case 'ComlinkAssignment':
         return this.visitComlinkAssignmentNode(node);
+      case 'ComlinkNoneLiteral':
+        return this.visitComlinkNoneLiteralNode(node);
       // UNUSED
       case 'FieldDefinition':
         return this.visitFieldDefinitionNode(node);
@@ -229,6 +233,25 @@ export class ExampleValidator implements ProfileAstVisitor {
     return isValid;
   }
 
+  visitComlinkNoneLiteralNode(node: ComlinkNoneLiteralNode): boolean {
+    assertDefinedStructure(this.currentStructure);
+
+    const { isValid } = validateNoneLiteral(this.currentStructure);
+
+    if (!isValid) {
+      this.errors.push({
+        kind: 'wrongStructure',
+        context: {
+          path: this.getPath(node),
+          expected: this.currentStructure,
+          actual: node,
+        },
+      });
+    }
+
+    return isValid;
+  }
+
   visitComlinkListLiteralNode(node: ComlinkListLiteralNode): boolean {
     if (this.structureIsPrepared(node)) {
       return true;
diff --git a/src/interpreter/profile-io-analyzer.ts b/src/interpreter/profile-io-analyzer.ts
index 869530c7..8fbc3a9c 100644
--- a/src/interpreter/profile-io-analyzer.ts
+++ b/src/interpreter/profile-io-analyzer.ts
@@ -1,6 +1,7 @@
 import {
   ComlinkAssignmentNode,
   ComlinkListLiteralNode,
+  ComlinkNoneLiteralNode,
   ComlinkObjectLiteralNode,
   ComlinkPrimitiveLiteralNode,
   DocumentedNode,
@@ -141,6 +142,8 @@ export class ProfileIOAnalyzer implements ProfileAstVisitor {
         return this.visitComlinkObjectLiteralNode(node);
       case 'ComlinkAssignment':
         return this.visitComlinkAssignmentNode(node);
+      case 'ComlinkNoneLiteral':
+        return this.visitComlinkNoneLiteralNode(node);
       default:
         assertUnreachable(node);
     }
@@ -328,6 +331,10 @@ export class ProfileIOAnalyzer implements ProfileAstVisitor {
     throw new Error('Not Implemented');
   }
 
+  visitComlinkNoneLiteralNode(_node: ComlinkNoneLiteralNode): void {
+    throw new Error('Not Implemented');
+  }
+
   /**
    * store the named fields for later reference
    */
diff --git a/src/interpreter/utils.ts b/src/interpreter/utils.ts
index 2b906a8d..d73c86f4 100644
--- a/src/interpreter/utils.ts
+++ b/src/interpreter/utils.ts
@@ -94,6 +94,8 @@ function formatLiteral(
     case 'PrimitiveLiteral':
     case 'ComlinkPrimitiveLiteral':
       return formatPrimitive(literal.value);
+    case 'ComlinkNoneLiteral':
+      return 'None';
     case 'ObjectLiteral':
     case 'ComlinkObjectLiteral':
       return `{${literal.fields.map(formatLiteral).join(', ')}}`;
@@ -269,6 +271,14 @@ export function validateListLiteral(
   return { isValid: false };
 }
 
+export function validateNoneLiteral(structure: StructureType): { isValid: boolean } {
+  if (structure.kind === 'NonNullStructure') {
+    return { isValid: false };
+  }
+
+  return { isValid: true }
+}
+
 export function getOutcomes(
   node: MapDefinitionNode | OperationDefinitionNode,
   isErrorFilter?: boolean
diff --git a/src/language/language.test.ts b/src/language/language.test.ts
index 6a872bed..55ce58f0 100644
--- a/src/language/language.test.ts
+++ b/src/language/language.test.ts
@@ -467,7 +467,10 @@ describe('profile', () => {
   it('should parse profile with examples', () => {
     const input = `
     usecase Foo {
-      input { f! string! }
+      input {
+        f! string!
+        fn string
+      }
       result number
       error enum {
         FORBIDDEN_WORD
@@ -478,6 +481,7 @@ describe('profile', () => {
         input {
           "hello has 5 letters"
           f = "hello"
+          fn = None
         }
         result 5
         // TODO: do we want this? async result undefined
@@ -531,6 +535,13 @@ describe('profile', () => {
                       title: 'hello has 5 letters',
                     },
                   },
+                  {
+                    kind: 'ComlinkAssignment',
+                    key: ['fn'],
+                    value: {
+                      kind: 'ComlinkNoneLiteral'
+                    }
+                  }
                 ],
               },
             },
diff --git a/src/language/lexer/lexer.test.ts b/src/language/lexer/lexer.test.ts
index 00b56f87..b11cda18 100644
--- a/src/language/lexer/lexer.test.ts
+++ b/src/language/lexer/lexer.test.ts
@@ -348,7 +348,7 @@ describe('lexer', () => {
     test('identifiers', () => {
       const lexer = new Lexer(
         new Source(
-          'ident my fier pls usecaseNOT modelout boolean b00lean a123456789_0'
+          'ident my fier pls usecaseNOT modelout boolean b00lean a123456789_0 None'
         )
       );
       const expectedTokens: (LexerTokenData | IdentifierValue)[] = [
@@ -362,6 +362,7 @@ describe('lexer', () => {
         'boolean',
         'b00lean',
         'a123456789_0',
+        'None',
         { kind: LexerTokenKind.SEPARATOR, separator: 'EOF' },
       ];
 
diff --git a/src/language/lexer/sublexer/jessie/expression.ts b/src/language/lexer/sublexer/jessie/expression.ts
index 8c59b5cb..815f64ff 100644
--- a/src/language/lexer/sublexer/jessie/expression.ts
+++ b/src/language/lexer/sublexer/jessie/expression.ts
@@ -864,7 +864,7 @@ function resolveTerminationTokens(
 
   // Tokens that are always terminator tokens
   // What isn't included here is the ts.SyntaxKind.EndOfFileToken token - this token is hardcoded into the scanner because it ignores nesting
-  if (!(ts.SyntaxKind.SingleLineCommentTrivia in termTokens)) {
+  if (!termTokens.includes(ts.SyntaxKind.SingleLineCommentTrivia)) {
     termTokens.push(ts.SyntaxKind.SingleLineCommentTrivia);
   }
 
diff --git a/src/language/lexer/token.ts b/src/language/lexer/token.ts
index eed36589..dc21ed89 100644
--- a/src/language/lexer/token.ts
+++ b/src/language/lexer/token.ts
@@ -179,7 +179,7 @@ export class LexerToken {
     /** Data of the token. */
     readonly data: LexerTokenData,
     readonly location: LocationSpan
-  ) {}
+  ) { }
 
   isSOF(): boolean {
     return (
diff --git a/src/language/syntax/rules/profile/literal.ts b/src/language/syntax/rules/profile/literal.ts
index 2223b28e..955055dd 100644
--- a/src/language/syntax/rules/profile/literal.ts
+++ b/src/language/syntax/rules/profile/literal.ts
@@ -2,6 +2,7 @@ import {
   ComlinkAssignmentNode,
   ComlinkListLiteralNode,
   ComlinkLiteralNode,
+  ComlinkNoneLiteralNode,
   ComlinkObjectLiteralNode,
   ComlinkPrimitiveLiteralNode,
 } from '@superfaceai/ast';
@@ -90,8 +91,20 @@ export const COMLINK_LIST_LITERAL: SyntaxRule<
   }
 );
 
+export const COMLINK_NONE_LITERAL: SyntaxRule<
+  WithLocation<ComlinkNoneLiteralNode>
+> = SyntaxRule.identifier('None').map(
+  (match): WithLocation<ComlinkNoneLiteralNode> => {
+    return {
+      kind: 'ComlinkNoneLiteral',
+      location: match.location,
+    };
+  }
+);
+
 export const COMLINK_LITERAL = SyntaxRule.or(
   COMLINK_PRIMITIVE_LITERAL,
+  COMLINK_NONE_LITERAL,
   COMLINK_OBJECT_LITERAL,
   COMLINK_LIST_LITERAL
 );
diff --git a/src/language/syntax/rules/profile/profile.test.ts b/src/language/syntax/rules/profile/profile.test.ts
index 826e39c9..e6c3219c 100644
--- a/src/language/syntax/rules/profile/profile.test.ts
+++ b/src/language/syntax/rules/profile/profile.test.ts
@@ -1484,7 +1484,7 @@ describe('profile syntax rules', () => {
 
         tesTok({ kind: LexerTokenKind.IDENTIFIER, identifier: 'version' }),
         tesTok({ kind: LexerTokenKind.OPERATOR, operator: '=' }),
-        tesTok({ kind: LexerTokenKind.STRING, string: '11.12' }),
+        tesTok({ kind: LexerTokenKind.STRING, string: '11.12.3' }),
       ];
       const stream = new ArrayLexerStream(tokens);
 
@@ -1498,7 +1498,7 @@ describe('profile syntax rules', () => {
             version: {
               major: 11,
               minor: 12,
-              patch: 0,
+              patch: 3,
             },
             documentation: {
               title: 'Title',
@@ -1522,7 +1522,7 @@ describe('profile syntax rules', () => {
 
         tesTok({ kind: LexerTokenKind.IDENTIFIER, identifier: 'version' }),
         tesTok({ kind: LexerTokenKind.OPERATOR, operator: '=' }),
-        tesTok({ kind: LexerTokenKind.STRING, string: '1' }),
+        tesTok({ kind: LexerTokenKind.STRING, string: '1.2.3' }),
 
         tesTok({ kind: LexerTokenKind.IDENTIFIER, identifier: 'model' }),
         tesTok({ kind: LexerTokenKind.IDENTIFIER, identifier: 'model1' }),
@@ -1559,8 +1559,8 @@ describe('profile syntax rules', () => {
                 name: 'profile',
                 version: {
                   major: 1,
-                  minor: 0,
-                  patch: 0,
+                  minor: 2,
+                  patch: 3,
                 },
               },
               tokens[1],
@@ -1630,6 +1630,23 @@ describe('profile syntax rules', () => {
         )
       );
     });
+
+    it('should require full version in profile header', () => {
+      const tokens: ReadonlyArray<LexerToken> = [
+        tesTok({ kind: LexerTokenKind.IDENTIFIER, identifier: 'name' }),
+        tesTok({ kind: LexerTokenKind.OPERATOR, operator: '=' }),
+        tesTok({ kind: LexerTokenKind.STRING, string: 'scope/profile' }),
+
+        tesTok({ kind: LexerTokenKind.IDENTIFIER, identifier: 'version' }),
+        tesTok({ kind: LexerTokenKind.OPERATOR, operator: '=' }),
+        tesTok({ kind: LexerTokenKind.STRING, string: '1.2' }),
+      ];
+      const stream = new ArrayLexerStream(tokens);
+
+      const rule = rules.PROFILE_HEADER;
+
+      expect(rule.tryMatch(stream)).not.toBeAMatch();
+    });
   });
 
   describe('comlink literals', () => {
@@ -1652,6 +1669,24 @@ describe('profile syntax rules', () => {
       );
     });
 
+    it('should parse none literal', () => {
+      const tokens: ReadonlyArray<LexerToken> = [
+        tesTok({ kind: LexerTokenKind.IDENTIFIER, identifier: 'None' }),
+      ];
+      const stream = new ArrayLexerStream(tokens);
+
+      const rule = rules.COMLINK_NONE_LITERAL;
+
+      expect(rule.tryMatch(stream)).toBeAMatch(
+        tesMatch(
+          {
+            kind: 'ComlinkNoneLiteral',
+          },
+          tokens[0]
+        )
+      );
+    });
+
     it('should parse object literal', () => {
       const tokens: ReadonlyArray<LexerToken> = [
         tesTok({ kind: LexerTokenKind.SEPARATOR, separator: '{' }),
diff --git a/src/language/syntax/rules/profile/profile.ts b/src/language/syntax/rules/profile/profile.ts
index 05e1c753..a7b3a118 100644
--- a/src/language/syntax/rules/profile/profile.ts
+++ b/src/language/syntax/rules/profile/profile.ts
@@ -22,8 +22,8 @@ import {
   UseCaseSlotDefinitionNode,
 } from '@superfaceai/ast';
 
+import { ProfileVersion } from '../../../../common';
 import { parseDocumentId } from '../../../../common/document/parser';
-import { VersionRange } from '../../../../common/document/version';
 import { PARSED_AST_VERSION, PARSED_VERSION } from '../../../../metadata';
 import { IdentifierTokenData, LexerTokenKind } from '../../../lexer/token';
 import {
@@ -568,14 +568,14 @@ const PROFILE_VERSION = SyntaxRule.followedBy(
     } & HasLocation
   >(version => {
     try {
-      const parsedVersion = VersionRange.fromString(version.data.string);
+      const parsedVersion = ProfileVersion.fromString(version.data.string);
 
       return {
         kind: 'match',
         value: {
           major: parsedVersion.major,
-          minor: parsedVersion.minor ?? 0,
-          patch: parsedVersion.patch ?? 0,
+          minor: parsedVersion.minor,
+          patch: parsedVersion.patch,
           label: parsedVersion.label,
           location: version.location,
         },
@@ -583,7 +583,7 @@ const PROFILE_VERSION = SyntaxRule.followedBy(
     } catch (error) {
       return { kind: 'nomatch' };
     }
-  }, 'semver version')
+  }, 'semver version in format `<major>.<minor>.<patch>`')
 ).map(([keyword, op, version]) => {
   return {
     version: {
diff --git a/yarn.lock b/yarn.lock
index 43d1c432..387d6433 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -566,10 +566,10 @@
   dependencies:
     "@sinonjs/commons" "^1.7.0"
 
-"@superfaceai/ast@^1.2.0":
-  version "1.2.0"
-  resolved "https://registry.yarnpkg.com/@superfaceai/ast/-/ast-1.2.0.tgz#f41823d550e0b0a05a8398be22a68b7b3912dde3"
-  integrity sha512-HMmdSUNzKuVgQ9g9YS/eiv3/CitSZks8eury8sAi2QbwT+n5f9SsVcmHxL2/QbkRCmlPpRqHJ6YSCqvBZ2fu1g==
+"@superfaceai/ast@^1.3.0":
+  version "1.3.0"
+  resolved "https://registry.yarnpkg.com/@superfaceai/ast/-/ast-1.3.0.tgz#15b8ef512616652478592b2469ba06303b713622"
+  integrity sha512-6zTaJKaZkR5kqk3axiE05FheRWYb0ykRSMy6quwrVn4fJmP/Z6KQ14KifqMtZTmWak+GsFPfun1n1reyGyHbJg==
   dependencies:
     ajv "^8.8.2"
     ajv-formats "^2.1.1"
@@ -2611,9 +2611,9 @@ json5@2.x, json5@^2.2.1:
   integrity sha512-1hqLFMSrGHRHxav9q9gNjJ5EXznIxGVO09xQRrwplcS8qs28pZ8s8hupZAmqDwZUmVZ2Qb2jnyPOWcDH8m8dlA==
 
 json5@^1.0.1:
-  version "1.0.1"
-  resolved "https://registry.yarnpkg.com/json5/-/json5-1.0.1.tgz#779fb0018604fa854eacbf6252180d83543e3dbe"
-  integrity sha512-aKS4WQjPenRxiQsC93MNfjx+nbF4PAdYzmd/1JIj8HYzqfbu86beTuNgXDzPknWk0n0uARlyewZo4s++ES36Ow==
+  version "1.0.2"
+  resolved "https://registry.yarnpkg.com/json5/-/json5-1.0.2.tgz#63d98d60f21b313b77c4d6da18bfa69d80e1d593"
+  integrity sha512-g1MWMLBiz8FKi1e4w0UyVL3w+iJceWAFBAaBnnGKOpNa5f8TLktkbre1+s6oICydWAm+HRUGTmI+//xv2hvXYA==
   dependencies:
     minimist "^1.2.0"
 
@@ -2747,9 +2747,9 @@ minimatch@^3.0.4, minimatch@^3.1.1, minimatch@^3.1.2:
     brace-expansion "^1.1.7"
 
 minimist@^1.2.0, minimist@^1.2.6:
-  version "1.2.6"
-  resolved "https://registry.yarnpkg.com/minimist/-/minimist-1.2.6.tgz#8637a5b759ea0d6e98702cfb3a9283323c93af44"
-  integrity sha512-Jsjnk4bw3YJqYzbdyBiNsPWHPfO++UGG749Cxs6peCu5Xg4nrena6OVxOYxrQTqww0Jmwt+Ref8rggumkTLz9Q==
+  version "1.2.7"
+  resolved "https://registry.yarnpkg.com/minimist/-/minimist-1.2.7.tgz#daa1c4d91f507390437c6a8bc01078e7000c4d18"
+  integrity sha512-bzfL1YUZsP41gmu/qjrEk0Q6i2ix/cVeAhbCbqH9u3zYutS1cLg00qhrD0M2MVdCcx4Sc0UpP2eBWo9rotpq6g==
 
 ms@2.0.0:
   version "2.0.0"