diff --git a/index.js b/index.js
deleted file mode 100644
index 67418cf..0000000
--- a/index.js
+++ /dev/null
@@ -1,3 +0,0 @@
-const Enmap = require('./src/index.js');
-
-module.exports = Enmap;
diff --git a/package.json b/package.json
index 300cc06..b119e1d 100755
--- a/package.json
+++ b/package.json
@@ -2,7 +2,7 @@
   "name": "enmap",
   "version": "5.7.0",
   "description": "A simple database wrapper to make sqlite database interactions much easier for beginners, with additional array helper methods.",
-  "types": "index.d.ts",
+  "main": "src/index.js",
   "scripts": {
     "test": "jest",
     "docs": "node ./docs/build.js"
@@ -47,5 +47,6 @@
     "jest": "^26.1.0",
     "jsdoc-to-markdown": "^6.0.1",
     "limax": "^2.1.0"
-  }
+  },
+  "types": "./typings/index.d.ts"
 }
diff --git a/src/index.js b/src/index.js
index 82aeb2e..0418942 100644
--- a/src/index.js
+++ b/src/index.js
@@ -193,7 +193,7 @@ class Enmap extends Map {
    */
   set(key, val, path = null) {
     if (isNil(key) || key.constructor.name !== 'String') {
-      throw new Err('Enmap require keys to be strings.', 'EnmapKeyTypeError');
+      throw new Err(`Enmap requires keys to be a string. Provided: ${isNil(key) ? 'nil' : key.constructor.name}`, 'EnmapKeyTypeError');
     }
     key = key.toString();
     let data = this.get(key);
@@ -273,7 +273,10 @@ class Enmap extends Map {
     if (isNil(key)) return null;
     this[_fetchCheck](key);
     key = key.toString();
-    const data = this.autoEnsure !== this.off ? this.ensure(key, this.autoEnsure) : super.get(key);
+    if(this.autoEnsure !== this.off && !this.has(key)) {
+      this.set(key, cloneDeep(this.autoEnsure));
+    }
+    const data = super.get(key);
     if (!isNil(path)) {
       this[_check](key, ['Object', 'Array']);
       return _get(data, path);
@@ -316,15 +319,6 @@ class Enmap extends Map {
     return rows.map(row => row.key);
   }
 
-  /**
-   * Migrates an Enmap from version 3 or lower to a Version 4 enmap, which is locked to sqlite backend only.
-   * This migration MUST be executed in version 3.1.4 of Enmap, along with appropriate providers.
-   * See https://enmap.evie.codes/install/upgrade for more details.
-   */
-  static async migrate() {
-    throw new Err('PLEASE DOWNGRADE TO ENMAP@3.1.4 TO USE THE MIGRATE TOOL', 'EnmapMigrationError');
-  }
-
   /**
    * Fetches every key from the persistent enmap and loads them into the current enmap value.
    * @return {Enmap} The enmap containing all values.
@@ -387,7 +381,7 @@ class Enmap extends Map {
     let { lastnum } = this.db.prepare("SELECT lastnum FROM 'internal::autonum' WHERE enmap = ?").get(this.name);
     lastnum++;
     this.db.prepare("INSERT OR REPLACE INTO 'internal::autonum' (enmap, lastnum) VALUES (?, ?)").run(this.name, lastnum);
-    return lastnum;
+    return lastnum.toString();
   }
 
   /**
@@ -656,7 +650,7 @@ class Enmap extends Map {
         if (this.polling) {
           this.db.prepare(`INSERT INTO 'internal::changes::${this.name}' (type, key, timestamp, pid) VALUES (?, ?, ?, ?);`).run('delete', key.toString(), Date.now(), process.pid);
         }
-        this.db.prepare(`DELETE FROM ${this.name} WHERE key = '${key}'`).run();
+        this.db.prepare(`DELETE FROM ${this.name} WHERE key = ?`).run(key);
         return this;
       }
       if (typeof this.changedCB === 'function') {
diff --git a/index.d.ts b/typings/index.d.ts
old mode 100755
new mode 100644
similarity index 100%
rename from index.d.ts
rename to typings/index.d.ts