diff --git a/SUPPORTED_LANGUAGES.md b/SUPPORTED_LANGUAGES.md
index c0a9ae6e58..44ab34d28a 100644
--- a/SUPPORTED_LANGUAGES.md
+++ b/SUPPORTED_LANGUAGES.md
@@ -47,11 +47,12 @@ The table below shows the full list of languages (and corresponding classes/alia
 | C3                      | c3                     | [highlightjs-c3](https://github.com/highlightjs/highlightjs-c3) |
 | Cache Object Script     | cos, cls               |         |
 | Candid                  | candid, did            | [highlightjs-motoko](https://github.com/rvanasa/highlightjs-motoko) |
-| Cap’n Proto             | capnproto, capnp       |         |
+| Cap'n Proto             | capnproto, capnp       |         |
+| Ceylon                  | ceylon                 |         |
 | Chaos                   | chaos, kaos            | [highlightjs-chaos](https://github.com/chaos-lang/highlightjs-chaos) |
 | Chapel                  | chapel, chpl           | [highlightjs-chapel](https://github.com/chapel-lang/highlightjs-chapel) |
 | Cisco CLI               | cisco                  | [highlightjs-cisco-cli](https://github.com/BMatheas/highlightjs-cisco-cli) |
-| Clojure                 | clojure, clj           |         |
+| Clojure                 | clojure, clj, edn      |         |
 | CMake                   | cmake, cmake.in        |         |
 | COBOL                   | cobol, standard-cobol  | [highlightjs-cobol](https://github.com/otterkit/highlightjs-cobol) |
 | CODEOWNERS              | codeowners             | [highlightjs-codeowners](https://github.com/highlightjs/highlightjs-codeowners) |
diff --git a/src/languages/cedar.js b/src/languages/cedar.js
new file mode 100644
index 0000000000..cda582a0cd
--- /dev/null
+++ b/src/languages/cedar.js
@@ -0,0 +1,140 @@
+/*
+Language: Cedar
+Description: Cedar is a language for writing authorization policies and making authorization decisions based on those policies.
+Website: https://www.cedarpolicy.com/
+Category: system
+*/
+
+/** @type LanguageFn */
+export default function(hljs) {
+  const GLOBALS = {
+    match: /\b(?:ip|decimal|datetime|duration)(?=\()/,
+    scope: 'built_in',
+  };
+
+  const VARIABLES = {
+    match: /\b(?<!\.)(principal|action|resource|context)\b/,
+    scope: 'variable',
+  };
+
+  const TEMPLATES = {
+    match: /(?:\?resource|\?principal)\b/,
+    scope: 'template-variable',
+  };
+
+  const POLICY = {
+    match: /\b(?<!\.)(permit|forbid|when|unless)\b/,
+    scope: 'keyword',
+  };
+
+  const KEYWORDS = {
+    keyword: ['if', 'then', 'else'],
+    literal: ['true', 'false'],
+  };
+
+  const PUNCTUATION = {
+    match: /(?:,|;|\.|\[|\]|\(|\)|{|\})/,
+    scope: 'punctuation',
+  };
+
+  const OPERATORS = {
+    begin:
+      /(?<!\w)/.source +
+      '(' +
+      [
+        '&&',
+        '\\|\\|',
+        '==',
+        '!=',
+        '>=',
+        '<=',
+        '>',
+        '<',
+        '\\+',
+        '-',
+        '\\*',
+        'in',
+        'like',
+        'has',
+        'is',
+      ].join('|') +
+      ')' +
+      /(?!\w)/.source,
+    scope: 'operator',
+    relevance: 0,
+  };
+
+  const INTEGER = {
+    scope: 'number',
+    begin: `0|\\-?[1-9](_?[0-9])*`,
+    relevance: 0,
+  };
+
+  const ENTITIES = {
+    match: /(?=\b)(([_a-zA-Z][_a-zA-Z0-9]*::)*[_a-zA-Z][_a-zA-Z0-9]*)(?=::)/,
+    scope: 'title.class',
+  };
+
+  const ISENTITY = {
+    match: [/is/, /\s+/, /([_a-zA-Z][_a-zA-Z0-9]*::)*[_a-zA-Z][_a-zA-Z0-9]*/],
+    scope: {
+      1: 'operator',
+      3: 'title.class',
+    },
+  };
+
+  const METHODS = {
+    scope: 'title.function.invoke',
+    begin: `(?=\.)(contains|containsAll|containsAny|isEmpty|getTag|hasTag)(?=\\()`,
+    relevance: 0,
+  };
+
+  const DECIMAL_METHODS = {
+    scope: 'title.function.invoke',
+    begin: `(?=\.)(lessThan|lessThanOrEqual|greaterThan|greaterThanOrEqual)(?=\\()`,
+    relevance: 0,
+  };
+
+  const IP_METHODS = {
+    scope: 'title.function.invoke',
+    begin: `(?=\.)(isIpv4|isIpv6|isLoopback|isMulticast|isInRange)(?=\\()`,
+    relevance: 0,
+  };
+
+  const DATETIME_METHODS = {
+    scope: 'title.function.invoke',
+    begin: `(?=\.)(offset|durationSince|toDate|toTime)(?=\\()`,
+    relevance: 0,
+  };
+
+  const DURATION_METHODS = {
+    scope: 'title.function.invoke',
+    begin: `(?=\.)(toMilliseconds|toSeconds|toMinutes|toHours|toDays)(?=\\()`,
+    relevance: 0,
+  };
+
+  return {
+    name: 'Cedar',
+    aliases: ['cedar'],
+    case_insensitive: false,
+    keywords: KEYWORDS,
+    contains: [
+      hljs.QUOTE_STRING_MODE,
+      hljs.C_LINE_COMMENT_MODE,
+      GLOBALS,
+      VARIABLES,
+      POLICY,
+      INTEGER,
+      PUNCTUATION,
+      ENTITIES,
+      ISENTITY,
+      OPERATORS,
+      METHODS,
+      DECIMAL_METHODS,
+      IP_METHODS,
+      DATETIME_METHODS,
+      DURATION_METHODS,
+      TEMPLATES,
+    ],
+  };
+}