diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
index cea4156..ad5781d 100644
--- a/.github/workflows/publish.yml
+++ b/.github/workflows/publish.yml
@@ -16,4 +16,4 @@ jobs:
       - uses: actions/checkout@v4
 
       - name: Publish package
-        run: npx jsr publish --allow-slow-types
+        run: npx jsr publish
diff --git a/grip.ts b/grip.ts
index ca37ed8..9f0b5b1 100644
--- a/grip.ts
+++ b/grip.ts
@@ -1,6 +1,6 @@
 interface Status {
   message?: string;
-  cause?: any;
+  cause?: unknown;
   Ok(): boolean;
   ok(): boolean;
   Fail(): boolean;
@@ -13,25 +13,25 @@ interface Status {
  * Error result
  */
 export class Err extends Error {
-  Ok() {
+  Ok(): boolean {
     return false;
   }
-  ok() {
+  ok(): boolean {
     return this.Ok();
   }
-  Fail() {
+  Fail(): boolean {
     return true;
   }
-  fail() {
+  fail(): boolean {
     return this.Fail();
   }
-  Of(cls: any) {
+  Of(cls: any): boolean {
     return this.cause instanceof cls || this instanceof cls;
   }
-  of(cls: any) {
+  of(cls: any): boolean {
     return this.Of(cls);
   }
-  static fromCatch(error: any) {
+  static fromCatch(error: any): Error {
     const e = new Err(typeof error === "string" ? error : error.message);
     e.cause = error;
     e.stack = error.stack;
@@ -43,25 +43,25 @@ export class Err extends Error {
  * Successful result
  */
 export class Ok {
-  Ok() {
+  Ok(): boolean {
     return true;
   }
-  ok() {
+  ok(): boolean {
     return this.Ok();
   }
-  Fail() {
+  Fail(): boolean {
     return false;
   }
-  fail() {
+  fail(): boolean {
     return this.Fail();
   }
-  Of(cls: any) {
+  Of(cls: any): boolean {
     return this instanceof cls;
   }
-  of(cls: any) {
+  of(cls: any): boolean {
     return this.Of(cls);
   }
-  toString() {
+  toString(): string {
     return "Ok";
   }
 }
@@ -76,6 +76,15 @@ interface IResult<T> {
   Fail(): boolean;
 }
 
+type IterResult<T> = {
+  [Symbol.asyncIterator](): AsyncGenerator<
+    Awaited<SafeResult<T>>,
+    void,
+    unknown
+  >;
+  [Symbol.iterator](): Generator<SafeResult<T>, void, unknown>;
+};
+
 class Result<T> extends Array<T | Status> implements IResult<T> {
   0: T;
   1: Status;
@@ -84,31 +93,31 @@ class Result<T> extends Array<T | Status> implements IResult<T> {
     this[0] = result;
     this[1] = status;
   }
-  get value() {
+  get value(): T {
     return this[0];
   }
-  get status() {
+  get status(): Status {
     return this[1];
   }
-  Ok() {
+  Ok(): boolean {
     return (this[1] as Status).Ok();
   }
-  ok() {
+  ok(): boolean {
     return this.Ok();
   }
-  Fail() {
+  Fail(): boolean {
     return (this[1] as Status).Fail();
   }
-  fail() {
+  fail(): boolean {
     return this.Fail();
   }
-  Of(cls: any) {
+  Of(cls: any): boolean {
     return (this[1] as Status).Of(cls);
   }
-  of(cls: any) {
+  of(cls: any): boolean {
     return this.Of(cls);
   }
-  Iter() {
+  Iter(): IterResult<T> {
     const value = this.value;
     const that = this;
     if (
@@ -136,7 +145,7 @@ class Result<T> extends Array<T | Status> implements IResult<T> {
       },
     };
   }
-  iter() {
+  iter(): IterResult<T> {
     return this.Iter();
   }
 }
@@ -183,8 +192,8 @@ export function grip<T>(action: T): SafeResult<T> {
     if (result instanceof Promise) {
       return promise<T>(result) as SafeResult<T>;
     }
-    return new Result<T>(result, new Ok()) as SafeResult<T>;
-  } catch (err: any) {
+    return new Result<T>(result as T, new Ok()) as SafeResult<T>;
+  } catch (err) {
     return new Result<T>(
       null as never,
       Err.fromCatch(err),
diff --git a/index.js b/index.js
index 293ec04..56fa561 100644
--- a/index.js
+++ b/index.js
@@ -1,19 +1,4 @@
 // grip.ts
-function grip(action) {
-  if (action instanceof Promise) {
-    return promise(action);
-  }
-  try {
-    const result = action();
-    if (result instanceof Promise) {
-      return promise(result);
-    }
-    return new Result(result, new Ok);
-  } catch (err) {
-    return new Result(null, Err.fromCatch(err));
-  }
-}
-
 class Err extends Error {
   Ok() {
     return false;
@@ -123,6 +108,20 @@ class Result extends Array {
     return this.Iter();
   }
 }
+function grip(action) {
+  if (action instanceof Promise) {
+    return promise(action);
+  }
+  try {
+    const result = action();
+    if (result instanceof Promise) {
+      return promise(result);
+    }
+    return new Result(result, new Ok);
+  } catch (err) {
+    return new Result(null, Err.fromCatch(err));
+  }
+}
 var promise = async (result) => {
   try {
     return new Result(await result, new Ok);
diff --git a/jsr.json b/jsr.json
index 0575027..a8ae250 100644
--- a/jsr.json
+++ b/jsr.json
@@ -1,5 +1,5 @@
 {
   "name": "@nesterow/grip",
-  "version": "0.0.2",
+  "version": "0.0.3",
   "exports": "./mod.ts"
 }
diff --git a/package.json b/package.json
index 8aa39e3..49fcda3 100644
--- a/package.json
+++ b/package.json
@@ -1,5 +1,5 @@
 {
-  "version": "0.0.2",
+  "version": "0.0.3",
   "author": {
     "name": "Anton Nesterov",
     "url": "https://github.com/nesterow"