diff --git a/build.gradle.kts b/build.gradle.kts
index 02c7bcb..2b8e187 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -3,7 +3,7 @@ plugins {
     alias(libs.plugins.teavm) // order matters?
 }
 
-val thisVersion = "0.1.0"
+val thisVersion = "0.2.0"
 
 group = "run.slicer"
 version = "$thisVersion-${libs.versions.jasm.get()}"
diff --git a/docs/index.html b/docs/index.html
index 7ba2a45..5203703 100644
--- a/docs/index.html
+++ b/docs/index.html
@@ -64,11 +64,11 @@
             const file = e.target.files[0];
             if (file) {
                 const reader = new FileReader();
-                reader.onload = (evt) => {
+                reader.onload = async (evt) => {
                     const start = Date.now();
                     console.log(`Disassembling ${file.name}...`);
 
-                    document.getElementById("file-content").textContent = disassemble(new Uint8Array(evt.target.result));
+                    document.getElementById("file-content").textContent = await disassemble(new Uint8Array(evt.target.result));
 
                     console.log(`Disassembled ${file.name} in ${Date.now() - start}ms.`);
                 };
diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
index ee3c1db..7315c2b 100644
--- a/gradle/libs.versions.toml
+++ b/gradle/libs.versions.toml
@@ -1,5 +1,5 @@
 [versions]
-jasm = "2.5.0"
+jasm = "2.6.0"
 teavm = "0.10.0"
 
 [libraries]
diff --git a/jasm.d.ts b/jasm.d.ts
index 8efe84c..8c9c99f 100644
--- a/jasm.d.ts
+++ b/jasm.d.ts
@@ -3,5 +3,5 @@ declare module "@run-slicer/jasm" {
         indent?: string;
     }
 
-    export function disassemble(b: Uint8Array, config?: DisassemblyConfig): string;
+    export function disassemble(b: Uint8Array, config?: DisassemblyConfig): Promise<string>;
 }
diff --git a/src/main/java/run/slicer/jasm/Main.java b/src/main/java/run/slicer/jasm/Main.java
index 4d6ddc9..2fe41e6 100644
--- a/src/main/java/run/slicer/jasm/Main.java
+++ b/src/main/java/run/slicer/jasm/Main.java
@@ -5,25 +5,35 @@
 import org.teavm.jso.JSByRef;
 import org.teavm.jso.JSExport;
 import org.teavm.jso.core.JSObjects;
+import org.teavm.jso.core.JSPromise;
+import org.teavm.jso.core.JSString;
 
 import java.io.IOException;
 import java.io.UncheckedIOException;
 
 public class Main {
     @JSExport
-    public static String disassemble(@JSByRef byte[] b, DisassemblyOptions options) {
+    public static JSPromise<JSString> disassemble(@JSByRef byte[] b, DisassemblyOptions options) {
         return disassemble0(b, options == null || JSObjects.isUndefined(options) ? JSObjects.create() : options);
     }
 
-    private static String disassemble0(byte[] b, DisassemblyOptions options) {
-        final var ctx = new PrintContext<>(options.indent());
+    private static JSPromise<JSString> disassemble0(byte[] b, DisassemblyOptions options) {
+        return new JSPromise<>((resolve, reject) -> {
+            new Thread(() -> {
+                try {
+                    final var ctx = new PrintContext<>(options.indent());
 
-        try {
-            new JvmClassPrinter(b).print(ctx);
-        } catch (IOException e) {
-            throw new UncheckedIOException(e);
-        }
+                    try {
+                        new JvmClassPrinter(b).print(ctx);
+                    } catch (IOException e) {
+                        throw new UncheckedIOException(e);
+                    }
 
-        return ctx.toString();
+                    resolve.accept(JSString.valueOf(ctx.toString()));
+                } catch (Throwable e) {
+                    reject.accept(e);
+                }
+            }).start();
+        });
     }
 }