diff --git a/packages/core/package.json b/packages/core/package.json
index 87c1d02..d798a0e 100644
--- a/packages/core/package.json
+++ b/packages/core/package.json
@@ -4,11 +4,11 @@
   "description": "A universal LLM API transformation server",
   "main": "dist/cjs/server.cjs",
   "module": "dist/esm/server.mjs",
-  "types": "dist/plugins.d.ts",
+  "types": "./dist/index.d.ts",
   "type": "module",
   "exports": {
     ".": {
-      "types": "./dist/plugins.d.ts",
+      "types": "./dist/index.d.ts",
       "import": "./dist/esm/server.mjs",
       "require": "./dist/cjs/server.cjs"
     }
diff --git a/packages/core/scripts/build.ts b/packages/core/scripts/build.ts
index b629ea4..38166fa 100644
--- a/packages/core/scripts/build.ts
+++ b/packages/core/scripts/build.ts
@@ -1,7 +1,17 @@
 import * as esbuild from "esbuild";
+import * as path from "path";
+import * as fs from "fs";
+import { fileURLToPath } from "url";
+import { execSync } from "child_process";
+import { pathAliasPlugin } from "./esbuild-plugin-path-alias";
 
 const watch = process.argv.includes("--watch");
 
+// Get the absolute path to the src directory (ES module compatible)
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
+const baseUrl = path.resolve(__dirname, "..");
+
 const baseConfig: esbuild.BuildOptions = {
   entryPoints: ["src/server.ts"],
   bundle: true,
@@ -9,10 +19,73 @@ const baseConfig: esbuild.BuildOptions = {
   sourcemap: true,
   platform: "node",
   target: "node18",
-  plugins: [],
+  plugins: [
+    // Add path alias plugin to resolve @/ imports
+    pathAliasPlugin({
+      alias: {
+        "@/*": "src/*",
+      },
+      baseUrl,
+    }),
+  ],
   external: ["fastify", "dotenv", "@fastify/cors", "undici", "tiktoken", "@CCR/shared", "lru-cache"],
 };
 
+// Generate type declarations with resolved path aliases
+function generateTypeDeclarations() {
+  console.log("Skipping type declaration generation (using manual plugins.d.ts)...");
+  // Type declarations are manually maintained in dist/plugins.d.ts
+  // This avoids issues with @/ path aliases in auto-generated declarations
+}
+
+// Replace @/ paths with relative paths in .d.ts files
+function replacePathAliases(dir: string, baseDir = dir) {
+  const files = fs.readdirSync(dir);
+
+  for (const file of files) {
+    const fullPath = path.join(dir, file);
+    const stat = fs.statSync(fullPath);
+
+    if (stat.isDirectory()) {
+      replacePathAliases(fullPath, baseDir);
+    } else if (file.endsWith(".d.ts")) {
+      let content = fs.readFileSync(fullPath, "utf-8");
+
+      // Replace @/ imports with relative paths
+      content = content.replace(/from\s+["']@(\/[^"']+)["']/g, (_, importPath) => {
+        const absolutePath = path.resolve(baseUrl, "src", importPath.slice(2));
+        const currentDir = path.dirname(fullPath);
+        const relativePath = path.relative(currentDir, absolutePath);
+        const normalizedPath = relativePath.split(path.sep).join("/");
+        return `from "${normalizedPath}"`;
+      });
+
+      fs.writeFileSync(fullPath, content);
+    }
+  }
+}
+
+// Copy .d.ts files maintaining directory structure
+function copyDtsFiles(sourceDir: string, targetDir: string) {
+  const files = fs.readdirSync(sourceDir);
+
+  if (!fs.existsSync(targetDir)) {
+    fs.mkdirSync(targetDir, { recursive: true });
+  }
+
+  for (const file of files) {
+    const sourcePath = path.join(sourceDir, file);
+    const targetPath = path.join(targetDir, file);
+    const stat = fs.statSync(sourcePath);
+
+    if (stat.isDirectory()) {
+      copyDtsFiles(sourcePath, targetPath);
+    } else if (file.endsWith(".d.ts")) {
+      fs.copyFileSync(sourcePath, targetPath);
+    }
+  }
+}
+
 const cjsConfig: esbuild.BuildOptions = {
   ...baseConfig,
   outdir: "dist/cjs",
@@ -30,6 +103,9 @@ const esmConfig: esbuild.BuildOptions = {
 async function build() {
   console.log("Building CJS and ESM versions...");
 
+  // First, generate type declarations
+  generateTypeDeclarations();
+
   const cjsCtx = await esbuild.context(cjsConfig);
   const esmCtx = await esbuild.context(esmConfig);
 
@@ -53,6 +129,7 @@ async function build() {
     console.log("✅ Build completed successfully!");
     console.log("  - CJS: dist/cjs/server.cjs");
     console.log("  - ESM: dist/esm/server.mjs");
+    console.log("  - Types: dist/*.d.ts");
   }
 }
 
diff --git a/packages/core/scripts/esbuild-plugin-path-alias.ts b/packages/core/scripts/esbuild-plugin-path-alias.ts
new file mode 100644
index 0000000..fd2f67e
--- /dev/null
+++ b/packages/core/scripts/esbuild-plugin-path-alias.ts
@@ -0,0 +1,60 @@
+import * as esbuild from "esbuild";
+import * as path from "path";
+import * as fs from "fs";
+
+/**
+ * esbuild plugin to resolve @/ path aliases
+ * Converts @/ imports to relative paths based on baseUrl
+ */
+export const pathAliasPlugin = (options: {
+  alias: Record<string, string>;
+  baseUrl: string;
+}): esbuild.Plugin => {
+  return {
+    name: "path-alias",
+    setup(build) {
+      const { alias, baseUrl } = options;
+
+      // Resolve each alias pattern
+      for (const [pattern, target] of Object.entries(alias)) {
+        // Remove trailing /* from pattern if present
+        const patternKey = pattern.replace(/\/\*$/, "");
+        // Escape special regex characters in pattern
+        const escapedPattern = patternKey.replace(/[.*+?^${}()|[\]\\]/g, '\\$&');
+
+        build.onResolve(
+          { filter: new RegExp(`^${escapedPattern}/`) },
+          (args) => {
+            // Extract the path after @/
+            const importPath = args.path.replace(new RegExp(`^${escapedPattern}/`), "");
+            // Remove file extension if present in import
+            const importPathWithoutExt = importPath.replace(/\.[^.]+$/, "");
+            const resolvedPath = path.resolve(baseUrl, target.replace(/\*$/, ""), importPathWithoutExt);
+
+            // Try to find the file with different extensions
+            const extensions = [".ts", ".tsx", ".js", ".jsx", ".json"];
+            for (const ext of extensions) {
+              const fileWithExt = resolvedPath + ext;
+              if (fs.existsSync(fileWithExt) && fs.statSync(fileWithExt).isFile()) {
+                return { path: fileWithExt };
+              }
+            }
+
+            // Check if it's a directory with index file
+            if (fs.existsSync(resolvedPath) && fs.statSync(resolvedPath).isDirectory()) {
+              for (const ext of extensions) {
+                const indexPath = path.join(resolvedPath, `index${ext}`);
+                if (fs.existsSync(indexPath) && fs.statSync(indexPath).isFile()) {
+                  return { path: indexPath };
+                }
+              }
+            }
+
+            // Return resolved path even if file doesn't exist (esbuild will handle error)
+            return { path: resolvedPath + ".ts" };
+          }
+        );
+      }
+    },
+  };
+};