diff --git a/package.json b/package.json
index f40f657..01c1ec1 100644
--- a/package.json
+++ b/package.json
@@ -5,6 +5,7 @@
   "version": "0.0.0",
   "packageManager": "yarn@4.12.0",
   "workspaces": [
+    "packages/core",
     "packages/javascript",
     "packages/sveltekit",
     "packages/sveltekit/playground"
diff --git a/packages/core/package.json b/packages/core/package.json
new file mode 100644
index 0000000..1c4cc2f
--- /dev/null
+++ b/packages/core/package.json
@@ -0,0 +1,40 @@
+{
+  "name": "@hawk.so/core",
+  "version": "1.0.0",
+  "description": "Base implementation for all Hawk.so SDKs",
+  "files": [
+    "dist"
+  ],
+  "main": "./dist/hawk-core.umd.js",
+  "module": "./dist/hawk-core.mjs",
+  "types": "dist/index.d.ts",
+  "exports": {
+    ".": {
+      "source": "./src/index.ts",
+      "types": "./dist/index.d.ts",
+      "import": "./dist/hawk-core.mjs",
+      "require": "./dist/hawk-core.umd.js"
+    }
+  },
+  "scripts": {
+    "build": "vite build"
+  },
+  "repository": {
+    "type": "git",
+    "url": "git+https://github.com/codex-team/hawk.javascript.git",
+    "directory": "packages/core"
+  },
+  "author": {
+    "name": "CodeX",
+    "email": "team@codex.so"
+  },
+  "license": "AGPL-3.0-only",
+  "bugs": {
+    "url": "https://github.com/codex-team/hawk.javascript/issues"
+  },
+  "homepage": "https://github.com/codex-team/hawk.javascript#readme",
+  "devDependencies": {
+    "vite": "^7.3.1",
+    "vite-plugin-dts": "^4.2.4"
+  }
+}
diff --git a/packages/core/src/index.ts b/packages/core/src/index.ts
new file mode 100644
index 0000000..fb7db31
--- /dev/null
+++ b/packages/core/src/index.ts
@@ -0,0 +1,3 @@
+export type { HawkStorage } from './types/storage';
+export type { UserManager } from './types/user-manager';
+export { StorageUserManager } from './types/storage-user-manager';
diff --git a/packages/core/src/types/storage-user-manager.ts b/packages/core/src/types/storage-user-manager.ts
new file mode 100644
index 0000000..76117d6
--- /dev/null
+++ b/packages/core/src/types/storage-user-manager.ts
@@ -0,0 +1,63 @@
+import { AffectedUser } from "@hawk.so/types";
+import { id } from "../utils/id";
+import { HawkStorage } from "./storage";
+import { UserManager } from "./user-manager";
+
+/**
+ * Storage key used to persist the user identifier.
+ */
+const HAWK_USER_STORAGE_KEY = 'hawk-user-id';
+
+/**
+ * {@link UserManager} implementation that persists the affected user
+ * via an injected {@link HawkStorage} backend.
+ */
+export class StorageUserManager implements UserManager {
+
+  /**
+   * Underlying storage used to read and write the user identifier.
+   */
+  private readonly storage: HawkStorage;
+
+  /**
+   * @param storage - Storage backend to use for persistence.
+   */
+  constructor(storage: HawkStorage) {
+    this.storage = storage;
+  }
+
+  /**
+   * Returns the stored user if one exists. Otherwise, generates a new identifier,
+   * saves it in storage under {@linkcode HAWK_USER_STORAGE_KEY}, and returns the new user.
+   */
+  getUser(): AffectedUser {
+    const storedId = this.storage.getItem(HAWK_USER_STORAGE_KEY);
+    if (storedId) {
+      return {
+        id: storedId,
+      };
+    }
+
+    const userId = id()
+    this.storage.setItem(HAWK_USER_STORAGE_KEY, userId);
+    return {
+      id: userId
+    };
+  }
+
+  /**
+   * Persists the given user's identifier in storage.
+   *
+   * @param user - The affected user to store.
+   */
+  setUser(user: AffectedUser): void {
+    this.storage.setItem(HAWK_USER_STORAGE_KEY, user.id);
+  }
+
+  /**
+   * Removes the stored user identifier from storage.
+   */
+  clear(): void {
+    this.storage.removeItem(HAWK_USER_STORAGE_KEY)
+  }
+}
diff --git a/packages/core/src/types/storage.ts b/packages/core/src/types/storage.ts
new file mode 100644
index 0000000..40bd694
--- /dev/null
+++ b/packages/core/src/types/storage.ts
@@ -0,0 +1,27 @@
+/**
+ * Abstract key–value storage contract used by Hawk internals
+ * (e.g. {@link StorageUserManager}) to persist data across sessions.
+ */
+export interface HawkStorage {
+  /**
+   * Returns the value associated with the given key, or `null` if none exists.
+   *
+   * @param key - Storage key to look up.
+   */
+  getItem(key: string): string | null
+
+  /**
+   * Persists a value under the given key.
+   *
+   * @param key - Storage key.
+   * @param value - Value to store.
+   */
+  setItem(key: string, value: string): void
+
+  /**
+   * Removes the entry for the given key.
+   *
+   * @param key - Storage key to remove.
+   */
+  removeItem(key: string): void
+}
diff --git a/packages/core/src/types/user-manager.ts b/packages/core/src/types/user-manager.ts
new file mode 100644
index 0000000..050100f
--- /dev/null
+++ b/packages/core/src/types/user-manager.ts
@@ -0,0 +1,26 @@
+import { AffectedUser } from "@hawk.so/types";
+
+/**
+ * Contract for user identity managers.
+ *
+ * Implementations are responsible for persisting and retrieving the
+ * {@link AffectedUser} that is attached to every error report sent by the catcher.
+ */
+export interface UserManager {
+  /**
+   * Returns the current affected user, creating one if none exists yet.
+   */
+  getUser(): AffectedUser
+
+  /**
+   * Replaces the stored user with the provided one.
+   *
+   * @param user - The affected user to persist.
+   */
+  setUser(user: AffectedUser): void
+
+  /**
+   * Removes any previously stored user data.
+   */
+  clear(): void
+}
diff --git a/packages/javascript/src/utils/id.ts b/packages/core/src/utils/id.ts
similarity index 100%
rename from packages/javascript/src/utils/id.ts
rename to packages/core/src/utils/id.ts
diff --git a/packages/core/tsconfig.json b/packages/core/tsconfig.json
new file mode 100644
index 0000000..56896f0
--- /dev/null
+++ b/packages/core/tsconfig.json
@@ -0,0 +1,10 @@
+{
+  "extends": "../../tsconfig.json",
+  "compilerOptions": {
+    "outDir": "dist",
+    "rootDir": "src"
+  },
+  "include": [
+    "src/**/*"
+  ]
+}
diff --git a/packages/core/vite.config.ts b/packages/core/vite.config.ts
new file mode 100644
index 0000000..2d03290
--- /dev/null
+++ b/packages/core/vite.config.ts
@@ -0,0 +1,22 @@
+import path from 'path';
+import dts from 'vite-plugin-dts';
+import { defineConfig } from 'vite';
+
+export default defineConfig(() => {
+  return {
+    build: {
+      copyPublicDir: false,
+      lib: {
+        entry: path.resolve(__dirname, 'src', 'index.ts'),
+        name: 'HawkCore',
+        fileName: 'hawk-core',
+      },
+    },
+
+    plugins: [
+      dts({
+        tsconfigPath: './tsconfig.json',
+      }),
+    ],
+  };
+});
diff --git a/packages/javascript/package.json b/packages/javascript/package.json
index 22e9827..d8eadf9 100644
--- a/packages/javascript/package.json
+++ b/packages/javascript/package.json
@@ -39,6 +39,7 @@
   },
   "homepage": "https://github.com/codex-team/hawk.javascript#readme",
   "dependencies": {
+    "@hawk.so/core": "workspace:^",
     "error-stack-parser": "^2.1.4"
   },
   "devDependencies": {
diff --git a/packages/javascript/src/catcher.ts b/packages/javascript/src/catcher.ts
index b18d868..0286bfb 100644
--- a/packages/javascript/src/catcher.ts
+++ b/packages/javascript/src/catcher.ts
@@ -4,7 +4,6 @@ import log from './utils/log';
 import StackParser from './modules/stackParser';
 import type { CatcherMessage, HawkInitialSettings, BreadcrumbsAPI, Transport } from './types';
 import { VueIntegration } from './integrations/vue';
-import { id } from './utils/id';
 import type {
   AffectedUser,
   EventContext,
@@ -19,6 +18,8 @@ import { isErrorProcessed, markErrorAsProcessed } from './utils/event';
 import { ConsoleCatcher } from './addons/consoleCatcher';
 import { BreadcrumbManager } from './addons/breadcrumbs';
 import { validateUser, validateContext, isValidEventPayload } from './utils/validation';
+import { StorageUserManager, UserManager } from "@hawk.so/core";
+import { HawkLocalStorage } from "./modules/local-storage";
 
 /**
  * Allow to use global VERSION, that will be overwritten by Webpack
@@ -62,11 +63,6 @@ export default class Catcher {
    */
   private readonly release: string | undefined;
 
-  /**
-   * Current authenticated user
-   */
-  private user: AffectedUser;
-
   /**
    * Any additional data passed by user for sending with all messages
    */
@@ -111,6 +107,11 @@ export default class Catcher {
    */
   private readonly breadcrumbManager: BreadcrumbManager | null;
 
+  /**
+   * Current authenticated user manager instance
+   */
+  private readonly userManager: UserManager = new StorageUserManager(new HawkLocalStorage());
+
   /**
    * Catcher constructor
    *
@@ -126,7 +127,9 @@ export default class Catcher {
     this.token = settings.token;
     this.debug = settings.debug || false;
     this.release = settings.release !== undefined ? String(settings.release) : undefined;
-    this.setUser(settings.user || Catcher.getGeneratedUser());
+    if (settings.user) {
+      this.setUser(settings.user);
+    }
     this.setContext(settings.context || undefined);
     this.beforeSend = settings.beforeSend;
     this.disableVueErrorHandler =
@@ -189,27 +192,6 @@ export default class Catcher {
     }
   }
 
-  /**
-   * Generates user if no one provided via HawkCatcher settings
-   * After generating, stores user for feature requests
-   */
-  private static getGeneratedUser(): AffectedUser {
-    let userId: string;
-    const LOCAL_STORAGE_KEY = 'hawk-user-id';
-    const storedId = localStorage.getItem(LOCAL_STORAGE_KEY);
-
-    if (storedId) {
-      userId = storedId;
-    } else {
-      userId = id();
-      localStorage.setItem(LOCAL_STORAGE_KEY, userId);
-    }
-
-    return {
-      id: userId,
-    };
-  }
-
   /**
    * Send test event from client
    */
@@ -272,14 +254,14 @@ export default class Catcher {
       return;
     }
 
-    this.user = user;
+    this.userManager.setUser(user);
   }
 
   /**
-   * Clear current user information (revert to generated user)
+   * Clear current user information
    */
   public clearUser(): void {
-    this.user = Catcher.getGeneratedUser();
+    this.userManager.clear()
   }
 
   /**
@@ -533,7 +515,7 @@ export default class Catcher {
   private getIntegrationId(): string {
     try {
       const decodedIntegrationToken: DecodedIntegrationToken = JSON.parse(atob(this.token));
-      const { integrationId } = decodedIntegrationToken;
+      const {integrationId} = decodedIntegrationToken;
 
       if (!integrationId || integrationId === '') {
         throw new Error();
@@ -568,7 +550,7 @@ export default class Catcher {
    * Current authenticated user
    */
   private getUser(): HawkJavaScriptEvent['user'] {
-    return this.user || null;
+    return this.userManager.getUser();
   }
 
   /**
diff --git a/packages/javascript/src/modules/local-storage.ts b/packages/javascript/src/modules/local-storage.ts
new file mode 100644
index 0000000..d7f0f1c
--- /dev/null
+++ b/packages/javascript/src/modules/local-storage.ts
@@ -0,0 +1,21 @@
+import { HawkStorage } from "@hawk.so/core";
+
+/**
+ * {@link HawkStorage} implementation backed by the browser's {@linkcode localStorage}.
+ */
+export class HawkLocalStorage implements HawkStorage {
+  /** @inheritDoc */
+  public getItem(key: string): string | null {
+    return localStorage.getItem(key);
+  }
+
+  /** @inheritDoc */
+  public setItem(key: string, value: string): void {
+    localStorage.setItem(key, value);
+  }
+
+  /** @inheritDoc */
+  public removeItem(key: string): void {
+    localStorage.removeItem(key);
+  }
+}
diff --git a/packages/javascript/vite.config.ts b/packages/javascript/vite.config.ts
index 47fe52e..65b622e 100644
--- a/packages/javascript/vite.config.ts
+++ b/packages/javascript/vite.config.ts
@@ -26,6 +26,7 @@ export default defineConfig(() => {
         fileName: 'hawk',
       },
       rollupOptions: {
+        external: ['@hawk.so/core'],
         plugins: [
           license({
             thirdParty: {
diff --git a/yarn.lock b/yarn.lock
index 317217e..fed6aff 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -576,10 +576,20 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@hawk.so/core@workspace:^, @hawk.so/core@workspace:packages/core":
+  version: 0.0.0-use.local
+  resolution: "@hawk.so/core@workspace:packages/core"
+  dependencies:
+    vite: "npm:^7.3.1"
+    vite-plugin-dts: "npm:^4.2.4"
+  languageName: unknown
+  linkType: soft
+
 "@hawk.so/javascript@npm:^3.0.0, @hawk.so/javascript@workspace:packages/javascript":
   version: 0.0.0-use.local
   resolution: "@hawk.so/javascript@workspace:packages/javascript"
   dependencies:
+    "@hawk.so/core": "workspace:^"
     "@hawk.so/types": "npm:0.5.8"
     error-stack-parser: "npm:^2.1.4"
     jsdom: "npm:^28.0.0"