diff --git a/.npmignore b/.npmignore
index 58fc57d..0561220 100644
--- a/.npmignore
+++ b/.npmignore
@@ -2,9 +2,8 @@ src/**/*.*
 dist/**/*.test.js
 dist/**/*.test.d.ts
 schemas/**/*.*
-json2esm.js
-json2types.js
-json2types-blocks.js
 tsconfig.json
 node_modules
-BUILD.md
\ No newline at end of file
+BUILD.md
+dist/specgen/**/*.*
+.github
\ No newline at end of file
diff --git a/package.json b/package.json
index 0cad2ea..de8c26b 100644
--- a/package.json
+++ b/package.json
@@ -1,24 +1,24 @@
 {
   "name": "typed-ocpp",
-  "version": "0.3.2",
+  "version": "0.3.3",
   "description": "A library for type-aware parsing, serialization and validation of OCPP messages",
   "main": "dist/index.js",
   "type": "module",
   "devDependencies": {
-    "@types/node": "^20.8.2",
-    "ajv": "^8.12.0",
-    "ajv-formats": "^2.1.1",
-    "json-schema-to-typescript": "^14.0.4",
-    "typescript": "^5.2.2"
+    "@types/node": "^20.14.2",
+    "ajv": "^8.16.0",
+    "ajv-formats": "^3.0.1",
+    "json-schema-to-typescript": "^14.0.5",
+    "typescript": "^5.4.5"
   },
   "scripts": {
     "test": "node --test --test-reporter=spec ./dist",
-    "specgen:ocpp16:types": "node json2types schemas/ocpp16 src/ocpp16/types.ts OCPP16",
-    "specgen:ocpp16:schemas": "node json2esm schemas/ocpp16 src/ocpp16/schemas.ts",
+    "specgen:ocpp16:types": "node specgen/json2types.js schemas/ocpp16 src/ocpp16/types.ts OCPP16",
+    "specgen:ocpp16:schemas": "node specgen/json2esm.js schemas/ocpp16 src/ocpp16/schemas.ts",
     "specgen:ocpp16:clean": "rm -f ./src/ocpp16/types.ts && rm -rf ./src/ocpp16/schemas.ts",
     "specgen:ocpp16": "npm run specgen:ocpp16:clean && npm run specgen:ocpp16:types && npm run specgen:ocpp16:schemas",
-    "specgen:ocpp20:types": "node json2types schemas/ocpp20 src/ocpp20/types.ts OCPP20",
-    "specgen:ocpp20:schemas": "node json2esm schemas/ocpp20 src/ocpp20/schemas.ts",
+    "specgen:ocpp20:types": "node specgen/json2types.js schemas/ocpp20 src/ocpp20/types.ts OCPP20",
+    "specgen:ocpp20:schemas": "node specgen/json2esm.js schemas/ocpp20 src/ocpp20/schemas.ts",
     "specgen:ocpp20:clean": "rm -f ./src/ocpp20/types.ts && rm -f ./src/ocpp20/schemas.ts",
     "specgen:ocpp20": "npm run specgen:ocpp20:clean && npm run specgen:ocpp20:types && npm run specgen:ocpp20:schemas",
     "specgen": "npm run specgen:ocpp16 && npm run specgen:ocpp20",
diff --git a/json2esm.js b/specgen/json2esm.js
similarity index 100%
rename from json2esm.js
rename to specgen/json2esm.js
diff --git a/json2types-blocks.js b/specgen/json2types-blocks.js
similarity index 98%
rename from json2types-blocks.js
rename to specgen/json2types-blocks.js
index 308661a..fb63f82 100644
--- a/json2types-blocks.js
+++ b/specgen/json2types-blocks.js
@@ -1,7 +1,10 @@
 /**
  * Code blocks to be deduplicated by ./json2types.js . 
  */
-export const deduplicate_blocks = { OCPP16: [], OCPP20: [] };
+export const deduplicate_blocks = { 
+  OCPP16: [],
+  OCPP20: [],
+ };
 
 deduplicate_blocks.OCPP16.push(`export interface CustomDataType {
   vendorId: string;
diff --git a/json2types.js b/specgen/json2types.js
similarity index 97%
rename from json2types.js
rename to specgen/json2types.js
index 2cd9ec9..b3d1ead 100644
--- a/json2types.js
+++ b/specgen/json2types.js
@@ -54,7 +54,8 @@ const output_file_header = `/*
     const input_file_data = await readFile(input_file_abspath, 'utf8');
 
     const input_schema = JSON.parse(input_file_data);
-    if (input_schema.$id?.indexOf(':') > -1) {
+    
+    if (mode === 'OCPP20' && input_schema.$id.indexOf(':') > -1) {
       // The schema files within the OCPP 2.0.1 spec have namespaced $id
       // attributes such as `urn:OCPP:Cp:2:2020:3:CancelReservationRequest`.
       // Here we get rid of the "urn" part of the $id so that json2ts will
diff --git a/src/common/ajv.ts b/src/common/ajv.ts
index 6099dc0..7f5f59c 100644
--- a/src/common/ajv.ts
+++ b/src/common/ajv.ts
@@ -1,16 +1,29 @@
 
 let __ajv: any = null;
 
+const isAjv = (ajv: any): boolean => {
+  return !!ajv 
+    && typeof ajv === 'object' 
+    && typeof ajv.validate === 'function'
+  ;
+};
+
 export const setAjv = (ajv: any) => {
+  if (!isAjv(ajv)) {
+    throw new Error(`
+      The argument provided to \`setAjv()\` does not look like an instance of
+      Ajv. See https://npm.im/typed-ocpp.
+    `);
+  }
   __ajv = ajv;
 };
 
 export const getAjv = (): any => {
-  if (!__ajv || typeof __ajv !== 'object' || typeof __ajv.validate !== 'function') {
+  if (!isAjv(__ajv)) {
     throw new Error(`
       The typed-ocpp library requires an instance of Ajv (https://npm.im/ajv)
       extended with the ajv-formats plugin (https://npm.im/ajv-formats) to be
-      provided using \`OCPP.setAjv()\`. See https://npm.im/typed-ocpp.
+      provided using \`setAjv()\`. See https://npm.im/typed-ocpp.
     `);
   }
   return __ajv;
diff --git a/src/index.test.js b/src/index.test.ts
similarity index 93%
rename from src/index.test.js
rename to src/index.test.ts
index a448643..4ea4dcc 100644
--- a/src/index.test.js
+++ b/src/index.test.ts
@@ -5,7 +5,7 @@ import { OCPP20 } from './index.js';
 import assert from 'node:assert';
 import { describe, it } from 'node:test';
 
-import './ajv.test.js';
+import './common/ajv.test.js';
 
 describe('schemas', () => {
 
diff --git a/src/ocpp16/schemas.ts b/src/ocpp16/schemas.ts
index ab9e726..2c84268 100644
--- a/src/ocpp16/schemas.ts
+++ b/src/ocpp16/schemas.ts
@@ -3,7 +3,7 @@
  * THIS FILE IS AUTOMATICALLY GENERATED AND SHOULD NEVER BE EDITED DIRECTLY.
  * SEE ../../BUILD.md
  *
- * GENERATED ON: 2024-05-27T08:46:12.016Z
+ * GENERATED ON: 2024-06-10T08:20:22.280Z
  *
  */
 
diff --git a/src/ocpp16/types.ts b/src/ocpp16/types.ts
index d081500..f77935a 100644
--- a/src/ocpp16/types.ts
+++ b/src/ocpp16/types.ts
@@ -3,7 +3,7 @@
  * THIS FILE IS AUTOMATICALLY GENERATED AND SHOULD NEVER BE EDITED DIRECTLY.
  * SEE ../../BUILD.md
  *
- * GENERATED ON: 2024-05-27T08:46:11.601Z
+ * GENERATED ON: 2024-06-10T08:20:21.870Z
  *
  */
 
diff --git a/src/ocpp20/schemas.ts b/src/ocpp20/schemas.ts
index 4595369..a50469b 100644
--- a/src/ocpp20/schemas.ts
+++ b/src/ocpp20/schemas.ts
@@ -3,7 +3,7 @@
  * THIS FILE IS AUTOMATICALLY GENERATED AND SHOULD NEVER BE EDITED DIRECTLY.
  * SEE ../../BUILD.md
  *
- * GENERATED ON: 2024-05-27T08:46:13.263Z
+ * GENERATED ON: 2024-06-10T08:20:23.517Z
  *
  */
 
diff --git a/src/ocpp20/types.ts b/src/ocpp20/types.ts
index 587ce49..0267974 100644
--- a/src/ocpp20/types.ts
+++ b/src/ocpp20/types.ts
@@ -3,7 +3,7 @@
  * THIS FILE IS AUTOMATICALLY GENERATED AND SHOULD NEVER BE EDITED DIRECTLY.
  * SEE ../../BUILD.md
  *
- * GENERATED ON: 2024-05-27T08:46:12.595Z
+ * GENERATED ON: 2024-06-10T08:20:22.859Z
  *
  */