diff --git a/api.md b/api.md
index f02997d5..75b8c48c 100644
--- a/api.md
+++ b/api.md
@@ -607,6 +607,16 @@ export interface MyObject {
 ```
 
 
+## [const-keyword](./test/programs/const-keyword)
+
+```ts
+const fn = <const T>(value: T) =>
+  ({ value });
+
+export type Object = ReturnType<typeof fn<"value">>;
+```
+
+
 ## [custom-dates](./test/programs/custom-dates)
 
 ```ts
diff --git a/package.json b/package.json
index e2a867f1..7f0bf141 100644
--- a/package.json
+++ b/package.json
@@ -47,7 +47,7 @@
     "path-equal": "^1.2.5",
     "safe-stable-stringify": "^2.2.0",
     "ts-node": "^10.9.1",
-    "typescript": "~4.9.5",
+    "typescript": "~5.1.0",
     "yargs": "^17.1.1"
   },
   "devDependencies": {
diff --git a/test/programs/const-keyword/main.ts b/test/programs/const-keyword/main.ts
new file mode 100644
index 00000000..11087d3d
--- /dev/null
+++ b/test/programs/const-keyword/main.ts
@@ -0,0 +1,4 @@
+const fn = <const T>(value: T) =>
+  ({ value });
+
+export type Object = ReturnType<typeof fn<"value">>;
diff --git a/test/programs/const-keyword/schema.json b/test/programs/const-keyword/schema.json
new file mode 100644
index 00000000..b3786f6e
--- /dev/null
+++ b/test/programs/const-keyword/schema.json
@@ -0,0 +1,12 @@
+{
+    "$schema": "http://json-schema.org/draft-07/schema#",
+    "properties": {
+        "value": {
+            "const": "value",
+            "type": "string"
+        }
+    },
+    "required": ["value"],
+    "type": "object"
+}
+
diff --git a/test/schema.test.ts b/test/schema.test.ts
index 1e6301b1..4f7fab62 100644
--- a/test/schema.test.ts
+++ b/test/schema.test.ts
@@ -523,3 +523,7 @@ describe("when reusing a generator", () => {
 describe("satisfies keyword - ignore from a \"satisfies\" and build by rally type", () => {
     assertSchema("satisfies-keyword", "Specific");
 });
+
+describe("const keyword", () => {
+    assertSchema("const-keyword", "Object");
+});
diff --git a/tsconfig.json b/tsconfig.json
index 2a7c0c73..2acf8e4c 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -19,8 +19,8 @@
         "noLib": false,
         "preserveConstEnums": true,
         "sourceMap": true,
-        "watch": false,
-        "typeRoots" : ["node_modules/@types"]
+        "typeRoots" : ["node_modules/@types"],
+        "ignoreDeprecations": "5.0"
     },
     "include": [
         "**/*.ts",
diff --git a/typescript-json-schema.ts b/typescript-json-schema.ts
index 7e668888..910df4ce 100644
--- a/typescript-json-schema.ts
+++ b/typescript-json-schema.ts
@@ -1052,8 +1052,8 @@ export class JsonSchemaGenerator {
             return !(
                 decls &&
                 decls.filter((decl) => {
-                    const mods = decl.modifiers;
-                    return mods && mods.filter((mod) => mod.kind === ts.SyntaxKind.PrivateKeyword).length > 0;
+                    const mods = (decl as any).modifiers;
+                    return mods && mods.filter((mod: any) => mod.kind === ts.SyntaxKind.PrivateKeyword).length > 0;
                 }).length > 0
             );
         });
@@ -1154,7 +1154,7 @@ export class JsonSchemaGenerator {
                 const requiredProps = props.reduce((required: string[], prop: ts.Symbol) => {
                     const def = {};
                     this.parseCommentsIntoDefinition(prop, def, {});
-                    const allUnionTypesFlags: number[] = (<any>prop).type?.types?.map?.((t: any) => t.flags) || [];
+                    const allUnionTypesFlags: number[] = (<any>prop).links?.type?.types?.map?.((t: any) => t.flags) || [];
                     if (
                         !(prop.flags & ts.SymbolFlags.Optional) &&
                         !(prop.flags & ts.SymbolFlags.Method) &&
@@ -1373,7 +1373,7 @@ export class JsonSchemaGenerator {
 
             if (definition.type === undefined) {
                 // if users override the type, do not try to infer it
-                if (typ.flags & ts.TypeFlags.Union) {
+                if (typ.flags & ts.TypeFlags.Union && (node === null || node.kind !== ts.SyntaxKind.EnumDeclaration)) {
                     this.getUnionDefinition(typ as ts.UnionType, unionModifier, definition);
                 } else if (typ.flags & ts.TypeFlags.Intersection) {
                     if (this.args.noExtraProps) {
diff --git a/yarn.lock b/yarn.lock
index 66820288..2888a713 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -894,10 +894,10 @@ type-detect@^4.0.0, type-detect@^4.0.5:
   resolved "https://registry.npmjs.org/type-detect/-/type-detect-4.0.8.tgz"
   integrity sha512-0fr/mIH1dlO+x7TlcMy+bIDqKPsw/70tVyeHW787goQjhmqaZe10uwLujubK9q9Lg6Fiho1KUKDYz0Z7k7g5/g==
 
-typescript@~4.9.5:
-  version "4.9.5"
-  resolved "https://registry.npmjs.org/typescript/-/typescript-4.9.5.tgz"
-  integrity sha512-1FXk9E2Hm+QzZQ7z+McJiHL4NW1F2EzMu9Nq9i3zAaGqibafqYwCVU6WyWAuyQRRzOlxou8xZSyXLEN8oKj24g==
+typescript@~5.1.0:
+  version "5.1.6"
+  resolved "https://registry.yarnpkg.com/typescript/-/typescript-5.1.6.tgz#02f8ac202b6dad2c0dd5e0913745b47a37998274"
+  integrity sha512-zaWCozRZ6DLEWAWFrVDz1H6FVXzUSfTy5FUMWsQlU8Ym5JP9eO4xkTIROFCQvhQf61z6O/G6ugw3SgAnvvm+HA==
 
 uri-js@^4.2.2:
   version "4.4.1"