diff --git a/bind/genjava.go b/bind/genjava.go
index 545f04f..ea66aec 100644
--- a/bind/genjava.go
+++ b/bind/genjava.go
@@ -303,11 +303,11 @@
 	}
 	if jinf == nil || jinf.genNoargCon {
 		// constructor for Go instantiated instances.
-		g.Printf("%s(Seq.Ref ref) { this.ref = ref; }\n\n", n)
+		g.Printf("%s(int refnum) { this.ref = Seq.trackGoRef(refnum); }\n\n", n)
 		if len(cons) == 0 {
 			// Generate default no-arg constructor
-			g.Printf("public %s() { this.ref = __New(); }\n\n", n)
-			g.Printf("private static native Seq.Ref __New();\n\n")
+			g.Printf("public %s() { this.ref = Seq.trackGoRef(__New()); }\n\n", n)
+			g.Printf("private static native int __New();\n\n")
 		}
 	}
 
@@ -420,7 +420,7 @@
 		}
 		g.Printf(");\n")
 	}
-	g.Printf("this.ref = ")
+	g.Printf("this.ref = Seq.trackGoRef(")
 	g.Printf("__%s(", f.Name())
 	for i := 0; i < params.Len(); i++ {
 		if i > 0 {
@@ -428,10 +428,10 @@
 		}
 		g.Printf(g.paramName(params, i))
 	}
-	g.Printf(");\n")
+	g.Printf("));\n")
 	g.Outdent()
 	g.Printf("}\n\n")
-	g.Printf("private static native Seq.Ref __%s(", f.Name())
+	g.Printf("private static native int __%s(", f.Name())
 	g.genFuncArgs(f, nil, false)
 	g.Printf(");\n\n")
 }
@@ -1118,7 +1118,7 @@
 	sig := f.Type().(*types.Signature)
 	res := sig.Results()
 
-	g.Printf("JNIEXPORT jobject JNICALL\n")
+	g.Printf("JNIEXPORT jint JNICALL\n")
 	g.Printf("Java_%s_%s_%s(JNIEnv *env, jclass clazz", g.jniPkgName(), java.JNIMangle(g.javaTypeName(sName)), java.JNIMangle("__"+f.Name()))
 	params := sig.Params()
 	for i := 0; i < params.Len(); i++ {
@@ -1154,8 +1154,7 @@
 		g.genCToJava("_err", "res.r1", res.At(1).Type(), modeRetained)
 		g.Printf("go_seq_maybe_throw_exception(env, _err);\n")
 	}
-	// Pass no proxy class so that the Seq.Ref is returned instead.
-	g.Printf("return go_seq_from_refnum(env, refnum, NULL, NULL);\n")
+	g.Printf("return refnum;\n")
 	g.Outdent()
 	g.Printf("}\n\n")
 }
@@ -1481,13 +1480,13 @@
 		}
 		g.Printf("clazz = (*env)->FindClass(env, %q);\n", g.jniClassSigPrefix(s.obj.Pkg())+g.javaTypeName(s.obj.Name()))
 		g.Printf("proxy_class_%s_%s = (*env)->NewGlobalRef(env, clazz);\n", g.pkgPrefix, s.obj.Name())
-		g.Printf("proxy_class_%s_%s_cons = (*env)->GetMethodID(env, clazz, \"<init>\", \"(Lgo/Seq$Ref;)V\");\n", g.pkgPrefix, s.obj.Name())
+		g.Printf("proxy_class_%s_%s_cons = (*env)->GetMethodID(env, clazz, \"<init>\", \"(I)V\");\n", g.pkgPrefix, s.obj.Name())
 	}
 	for _, iface := range g.interfaces {
 		pkg := iface.obj.Pkg()
 		g.Printf("clazz = (*env)->FindClass(env, %q);\n", g.jniClassSigPrefix(pkg)+JavaClassName(pkg)+"$proxy"+iface.obj.Name())
 		g.Printf("proxy_class_%s_%s = (*env)->NewGlobalRef(env, clazz);\n", g.pkgPrefix, iface.obj.Name())
-		g.Printf("proxy_class_%s_%s_cons = (*env)->GetMethodID(env, clazz, \"<init>\", \"(Lgo/Seq$Ref;)V\");\n", g.pkgPrefix, iface.obj.Name())
+		g.Printf("proxy_class_%s_%s_cons = (*env)->GetMethodID(env, clazz, \"<init>\", \"(I)V\");\n", g.pkgPrefix, iface.obj.Name())
 		if isErrorType(iface.obj.Type()) {
 			// As a special case, Java Exceptions are passed to Go pretending to implement the Go error interface.
 			// To complete the illusion, use the Throwable.getMessage method for proxied calls to the error.Error method.
@@ -1532,12 +1531,10 @@
 			g.genJNIConstructor(f, sName)
 		}
 		if len(cons) == 0 && (jinf == nil || jinf.genNoargCon) {
-			g.Printf("JNIEXPORT jobject JNICALL\n")
+			g.Printf("JNIEXPORT jint JNICALL\n")
 			g.Printf("Java_%s_%s_%s(JNIEnv *env, jclass clazz) {\n", g.jniPkgName(), java.JNIMangle(g.javaTypeName(sName)), java.JNIMangle("__New"))
 			g.Indent()
-			g.Printf("int32_t refnum = new_%s_%s();\n", g.pkgPrefix, sName)
-			// Pass no proxy class so that the Seq.Ref is returned instead.
-			g.Printf("return go_seq_from_refnum(env, refnum, NULL, NULL);\n")
+			g.Printf("return new_%s_%s();\n", g.pkgPrefix, sName)
 			g.Outdent()
 			g.Printf("}\n\n")
 		}
@@ -1604,7 +1601,7 @@
 		g.Printf(" implements Seq.Proxy, %s {\n", g.javaTypeName(n))
 		g.Indent()
 		g.genProxyImpl("proxy" + n)
-		g.Printf("proxy%s(Seq.Ref ref) { this.ref = ref; }\n\n", n)
+		g.Printf("proxy%s(int refnum) { this.ref = Seq.trackGoRef(refnum); }\n\n", n)
 
 		if isErrorType(iface.obj.Type()) {
 			g.Printf("@Override public String getMessage() { return error(); }\n\n")
diff --git a/bind/java/Seq.java b/bind/java/Seq.java
index b421a93..59a0880 100644
--- a/bind/java/Seq.java
+++ b/bind/java/Seq.java
@@ -66,6 +66,22 @@
 		return o.incRefnum();
 	}
 
+	// trackGoRef returns a Ref for a Go refnum.
+	//
+	// TODO(crawshaw): We could cut down allocations for frequently
+	// sent Go objects by maintaining a map to weak references. This
+	// however, would require allocating two objects per reference
+	// instead of one. It also introduces weak references, the bane
+	// of any Java debugging session.
+	//
+	// When we have real code, examine the tradeoffs.
+	public static Ref trackGoRef(int refnum) {
+		if (refnum > 0) {
+			throw new RuntimeException("trackGoRef called with Java refnum " + refnum);
+		}
+		return new Ref(refnum, null);
+	}
+
 	public static Ref getRef(int refnum) {
 		return tracker.get(refnum);
 	}
@@ -116,6 +132,9 @@
 		public final Object obj;  // for Java obj: pointers to the Java obj.
 
 		Ref(int refnum, Object o) {
+			if (refnum < 0) {
+				throw new RuntimeException("Ref instantiated with a Go refnum " + refnum);
+			}
 			this.refnum = refnum;
 			this.refcnt = 0;
 			this.obj = o;
@@ -221,29 +240,19 @@
 			}
 		}
 
-		// get returns an existing Ref to either a Java or Go object.
-		// It may be the first time we have seen the Go object.
-		//
-		// TODO(crawshaw): We could cut down allocations for frequently
-		// sent Go objects by maintaining a map to weak references. This
-		// however, would require allocating two objects per reference
-		// instead of one. It also introduces weak references, the bane
-		// of any Java debugging session.
-		//
-		// When we have real code, examine the tradeoffs.
+		// get returns an existing Ref to a Java object.
 		synchronized Ref get(int refnum) {
+			if (refnum < 0) {
+				throw new RuntimeException("ref called with Go refnum " + refnum);
+			}
 			if (refnum == NULL_REFNUM) {
 				return nullRef;
-			} else if (refnum > 0) {
-				Ref ref = javaObjs.get(refnum);
-				if (ref == null) {
-					throw new RuntimeException("unknown java Ref: "+refnum);
-				}
-				return ref;
-			} else {
-				// Go object.
-				return new Ref(refnum, null);
 			}
+			Ref ref = javaObjs.get(refnum);
+			if (ref == null) {
+				throw new RuntimeException("unknown java Ref: "+refnum);
+			}
+			return ref;
 		}
 	}
 
diff --git a/bind/java/seq_android.c.support b/bind/java/seq_android.c.support
index b3aafad..c4fafc2 100644
--- a/bind/java/seq_android.c.support
+++ b/bind/java/seq_android.c.support
@@ -250,23 +250,19 @@
 	if (refnum == NULL_REFNUM) {
 		return NULL;
 	}
+	if (refnum < 0) { // Go object
+		// return new <Proxy>(refnum)
+		return (*env)->NewObject(env, proxy_class, proxy_cons, refnum);
+	}
 	// Seq.Ref ref = Seq.getRef(refnum)
 	jobject ref = (*env)->CallStaticObjectMethod(env, seq_class, seq_getRef, (jint)refnum);
 	if (ref == NULL) {
 		LOG_FATAL("Unknown reference: %d", refnum);
 	}
-	if (refnum > 0) { // Java object
-		// Go incremented the reference count just before passing the refnum. Decrement it here.
-		(*env)->CallStaticVoidMethod(env, seq_class, seq_decRef, (jint)refnum);
-		// return ref.obj
-		return (*env)->GetObjectField(env, ref, ref_objField);
-	} else if (proxy_class != NULL) {
-		// return new <Proxy>(ref)
-		return (*env)->NewObject(env, proxy_class, proxy_cons, ref);
-	} else {
-		// We're inside a Java proxy constructor and only need the Seq.Ref
-		return ref;
-	}
+	// Go incremented the reference count just before passing the refnum. Decrement it here.
+	(*env)->CallStaticVoidMethod(env, seq_class, seq_decRef, (jint)refnum);
+	// return ref.obj
+	return (*env)->GetObjectField(env, ref, ref_objField);
 }
 
 // go_seq_to_java_string converts a nstring to a jstring.
diff --git a/bind/testdata/classes.java.c.golden b/bind/testdata/classes.java.c.golden
index bb0c974..dac9d2e 100644
--- a/bind/testdata/classes.java.c.golden
+++ b/bind/testdata/classes.java.c.golden
@@ -752,13 +752,13 @@
     jclass clazz;
     clazz = (*env)->FindClass(env, "java/Future");
     proxy_class_java_Future = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_java_Future_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_java_Future_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "java/Object");
     proxy_class_java_Object = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_java_Object_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_java_Object_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "java/Runnable");
     proxy_class_java_Runnable = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_java_Runnable_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_java_Runnable_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
 }
 
 JNIEXPORT jobject JNICALL
@@ -768,10 +768,9 @@
     return _r0;
 }
 
-JNIEXPORT jobject JNICALL
+JNIEXPORT jint JNICALL
 Java_java_Future__1_1New(JNIEnv *env, jclass clazz) {
-    int32_t refnum = new_java_Future();
-    return go_seq_from_refnum(env, refnum, NULL, NULL);
+    return new_java_Future();
 }
 
 JNIEXPORT jobject JNICALL
@@ -811,10 +810,10 @@
     return _r0;
 }
 
-JNIEXPORT jobject JNICALL
+JNIEXPORT jint JNICALL
 Java_java_InputStream__1_1NewInputStream(JNIEnv *env, jclass clazz) {
     int32_t refnum = proxyjava__NewInputStream();
-    return go_seq_from_refnum(env, refnum, NULL, NULL);
+    return refnum;
 }
 
 JNIEXPORT jint JNICALL
@@ -842,10 +841,9 @@
     return _r0;
 }
 
-JNIEXPORT jobject JNICALL
+JNIEXPORT jint JNICALL
 Java_java_Object__1_1New(JNIEnv *env, jclass clazz) {
-    int32_t refnum = new_java_Object();
-    return go_seq_from_refnum(env, refnum, NULL, NULL);
+    return new_java_Object();
 }
 
 JNIEXPORT void JNICALL
@@ -863,10 +861,9 @@
     return _r0;
 }
 
-JNIEXPORT jobject JNICALL
+JNIEXPORT jint JNICALL
 Java_java_Runnable__1_1New(JNIEnv *env, jclass clazz) {
-    int32_t refnum = new_java_Runnable();
-    return go_seq_from_refnum(env, refnum, NULL, NULL);
+    return new_java_Runnable();
 }
 
 JNIEXPORT void JNICALL
diff --git a/bind/testdata/classes.java.golden b/bind/testdata/classes.java.golden
index 9cc75b1..113927f 100644
--- a/bind/testdata/classes.java.golden
+++ b/bind/testdata/classes.java.golden
@@ -17,11 +17,11 @@
           return refnum;
     }
     
-    Future(Seq.Ref ref) { this.ref = ref; }
+    Future(int refnum) { this.ref = Seq.trackGoRef(refnum); }
     
-    public Future() { this.ref = __New(); }
+    public Future() { this.ref = Seq.trackGoRef(__New()); }
     
-    private static native Seq.Ref __New();
+    private static native int __New();
     
     public final native java.util.concurrent.Future getFuture();
     public final native void setFuture(java.util.concurrent.Future v);
@@ -54,10 +54,10 @@
     
     public InputStream() {
         super();
-        this.ref = __NewInputStream();
+        this.ref = Seq.trackGoRef(__NewInputStream());
     }
     
-    private static native Seq.Ref __NewInputStream();
+    private static native int __NewInputStream();
     
     public final native java.io.InputStream getInputStream();
     public final native void setInputStream(java.io.InputStream v);
@@ -84,11 +84,11 @@
           return refnum;
     }
     
-    Object(Seq.Ref ref) { this.ref = ref; }
+    Object(int refnum) { this.ref = Seq.trackGoRef(refnum); }
     
-    public Object() { this.ref = __New(); }
+    public Object() { this.ref = Seq.trackGoRef(__New()); }
     
-    private static native Seq.Ref __New();
+    private static native int __New();
     
     public final native java.lang.Object getObject();
     public final native void setObject(java.lang.Object v);
@@ -114,11 +114,11 @@
           return refnum;
     }
     
-    Runnable(Seq.Ref ref) { this.ref = ref; }
+    Runnable(int refnum) { this.ref = Seq.trackGoRef(refnum); }
     
-    public Runnable() { this.ref = __New(); }
+    public Runnable() { this.ref = Seq.trackGoRef(__New()); }
     
-    private static native Seq.Ref __New();
+    private static native int __New();
     
     public final native java.lang.Runnable getRunnable();
     public final native void setRunnable(java.lang.Runnable v);
diff --git a/bind/testdata/doc.java.c.golden b/bind/testdata/doc.java.c.golden
index 3b300dc..5b07165 100644
--- a/bind/testdata/doc.java.c.golden
+++ b/bind/testdata/doc.java.c.golden
@@ -24,16 +24,16 @@
     jclass clazz;
     clazz = (*env)->FindClass(env, "doc/NoDoc");
     proxy_class_doc_NoDoc = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_doc_NoDoc_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_doc_NoDoc_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "doc/S");
     proxy_class_doc_S = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_doc_S_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_doc_S_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "doc/S2");
     proxy_class_doc_S2 = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_doc_S2_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_doc_S2_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "doc/Doc$proxyI");
     proxy_class_doc_I = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_doc_I_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_doc_I_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "doc/I");
     mid_I_IM = (*env)->GetMethodID(env, clazz, "im", "()V");
     
@@ -51,16 +51,15 @@
     return _r0;
 }
 
-JNIEXPORT jobject JNICALL
+JNIEXPORT jint JNICALL
 Java_doc_NoDoc__1_1New(JNIEnv *env, jclass clazz) {
-    int32_t refnum = new_doc_NoDoc();
-    return go_seq_from_refnum(env, refnum, NULL, NULL);
+    return new_doc_NoDoc();
 }
 
-JNIEXPORT jobject JNICALL
+JNIEXPORT jint JNICALL
 Java_doc_S__1_1NewS(JNIEnv *env, jclass clazz) {
     int32_t refnum = proxydoc__NewS();
-    return go_seq_from_refnum(env, refnum, NULL, NULL);
+    return refnum;
 }
 
 JNIEXPORT void JNICALL
@@ -135,10 +134,9 @@
     return _r0;
 }
 
-JNIEXPORT jobject JNICALL
+JNIEXPORT jint JNICALL
 Java_doc_S2__1_1New(JNIEnv *env, jclass clazz) {
-    int32_t refnum = new_doc_S2();
-    return go_seq_from_refnum(env, refnum, NULL, NULL);
+    return new_doc_S2();
 }
 
 JNIEXPORT void JNICALL
diff --git a/bind/testdata/doc.java.golden b/bind/testdata/doc.java.golden
index db94df5..6c62816 100644
--- a/bind/testdata/doc.java.golden
+++ b/bind/testdata/doc.java.golden
@@ -20,11 +20,11 @@
           return refnum;
     }
     
-    NoDoc(Seq.Ref ref) { this.ref = ref; }
+    NoDoc(int refnum) { this.ref = Seq.trackGoRef(refnum); }
     
-    public NoDoc() { this.ref = __New(); }
+    public NoDoc() { this.ref = Seq.trackGoRef(__New()); }
     
-    private static native Seq.Ref __New();
+    private static native int __New();
     
     @Override public boolean equals(Object o) {
         if (o == null || !(o instanceof NoDoc)) {
@@ -71,12 +71,12 @@
      * NewS is a constructor.
      */
     public S() {
-        this.ref = __NewS();
+        this.ref = Seq.trackGoRef(__NewS());
     }
     
-    private static native Seq.Ref __NewS();
+    private static native int __NewS();
     
-    S(Seq.Ref ref) { this.ref = ref; }
+    S(int refnum) { this.ref = Seq.trackGoRef(refnum); }
     
     /**
      * SF is a field.
@@ -200,11 +200,11 @@
           return refnum;
     }
     
-    S2(Seq.Ref ref) { this.ref = ref; }
+    S2(int refnum) { this.ref = Seq.trackGoRef(refnum); }
     
-    public S2() { this.ref = __New(); }
+    public S2() { this.ref = Seq.trackGoRef(__New()); }
     
-    private static native Seq.Ref __New();
+    private static native int __New();
     
     @Override public boolean equals(Object o) {
         if (o == null || !(o instanceof S2)) {
@@ -274,7 +274,7 @@
               return refnum;
         }
         
-        proxyI(Seq.Ref ref) { this.ref = ref; }
+        proxyI(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native void im();
     }
diff --git a/bind/testdata/ignore.java.c.golden b/bind/testdata/ignore.java.c.golden
index 6a29ff0..9511e21 100644
--- a/bind/testdata/ignore.java.c.golden
+++ b/bind/testdata/ignore.java.c.golden
@@ -23,10 +23,10 @@
     jclass clazz;
     clazz = (*env)->FindClass(env, "ignore/S");
     proxy_class_ignore_S = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_ignore_S_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_ignore_S_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "ignore/Ignore$proxyI");
     proxy_class_ignore_I = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_ignore_I_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_ignore_I_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "ignore/I");
     // skipped method I.Argument with unsupported parameter or return types
     
@@ -39,10 +39,9 @@
 
 // skipped function Result with unsupported parameter or return types
 
-JNIEXPORT jobject JNICALL
+JNIEXPORT jint JNICALL
 Java_ignore_S__1_1New(JNIEnv *env, jclass clazz) {
-    int32_t refnum = new_ignore_S();
-    return go_seq_from_refnum(env, refnum, NULL, NULL);
+    return new_ignore_S();
 }
 
 // skipped function S.Argument with unsupported parameter or return types
diff --git a/bind/testdata/ignore.java.golden b/bind/testdata/ignore.java.golden
index d00b3b7..76aad8a 100644
--- a/bind/testdata/ignore.java.golden
+++ b/bind/testdata/ignore.java.golden
@@ -17,11 +17,11 @@
           return refnum;
     }
     
-    S(Seq.Ref ref) { this.ref = ref; }
+    S(int refnum) { this.ref = Seq.trackGoRef(refnum); }
     
-    public S() { this.ref = __New(); }
+    public S() { this.ref = Seq.trackGoRef(__New()); }
     
-    private static native Seq.Ref __New();
+    private static native int __New();
     
     // skipped field S.F with unsupported type: interface{}
     
@@ -96,7 +96,7 @@
               return refnum;
         }
         
-        proxyI(Seq.Ref ref) { this.ref = ref; }
+        proxyI(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         // skipped method I.Argument with unsupported parameter or return types
         
diff --git a/bind/testdata/interfaces.java.c.golden b/bind/testdata/interfaces.java.c.golden
index 0f11d5d..b3c2138 100644
--- a/bind/testdata/interfaces.java.c.golden
+++ b/bind/testdata/interfaces.java.c.golden
@@ -43,56 +43,56 @@
     jclass clazz;
     clazz = (*env)->FindClass(env, "interfaces/Interfaces$proxyError");
     proxy_class_interfaces_Error = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_interfaces_Error_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_interfaces_Error_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "interfaces/Error");
     mid_Error_Err = (*env)->GetMethodID(env, clazz, "err", "()V");
     
     clazz = (*env)->FindClass(env, "interfaces/Interfaces$proxyI");
     proxy_class_interfaces_I = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_interfaces_I_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_interfaces_I_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "interfaces/I");
     mid_I_Rand = (*env)->GetMethodID(env, clazz, "rand", "()I");
     
     clazz = (*env)->FindClass(env, "interfaces/Interfaces$proxyI1");
     proxy_class_interfaces_I1 = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_interfaces_I1_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_interfaces_I1_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "interfaces/I1");
     mid_I1_J = (*env)->GetMethodID(env, clazz, "j", "()V");
     
     clazz = (*env)->FindClass(env, "interfaces/Interfaces$proxyI2");
     proxy_class_interfaces_I2 = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_interfaces_I2_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_interfaces_I2_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "interfaces/I2");
     mid_I2_G = (*env)->GetMethodID(env, clazz, "g", "()V");
     
     clazz = (*env)->FindClass(env, "interfaces/Interfaces$proxyI3");
     proxy_class_interfaces_I3 = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_interfaces_I3_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_interfaces_I3_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "interfaces/I3");
     mid_I3_F = (*env)->GetMethodID(env, clazz, "f", "()Linterfaces/I1;");
     
     clazz = (*env)->FindClass(env, "interfaces/Interfaces$proxyInterfaces");
     proxy_class_interfaces_Interfaces = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_interfaces_Interfaces_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_interfaces_Interfaces_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "interfaces/Interfaces_");
     mid_Interfaces_SomeMethod = (*env)->GetMethodID(env, clazz, "someMethod", "()V");
     
     clazz = (*env)->FindClass(env, "interfaces/Interfaces$proxyLargerI");
     proxy_class_interfaces_LargerI = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_interfaces_LargerI_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_interfaces_LargerI_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "interfaces/LargerI");
     mid_LargerI_AnotherFunc = (*env)->GetMethodID(env, clazz, "anotherFunc", "()V");
     mid_LargerI_Rand = (*env)->GetMethodID(env, clazz, "rand", "()I");
     
     clazz = (*env)->FindClass(env, "interfaces/Interfaces$proxySameI");
     proxy_class_interfaces_SameI = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_interfaces_SameI_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_interfaces_SameI_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "interfaces/SameI");
     mid_SameI_Rand = (*env)->GetMethodID(env, clazz, "rand", "()I");
     
     clazz = (*env)->FindClass(env, "interfaces/Interfaces$proxyWithParam");
     proxy_class_interfaces_WithParam = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_interfaces_WithParam_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_interfaces_WithParam_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "interfaces/WithParam");
     mid_WithParam_HasParam = (*env)->GetMethodID(env, clazz, "hasParam", "(Z)V");
     
diff --git a/bind/testdata/interfaces.java.golden b/bind/testdata/interfaces.java.golden
index 87402b7..b7bfd86 100644
--- a/bind/testdata/interfaces.java.golden
+++ b/bind/testdata/interfaces.java.golden
@@ -159,7 +159,7 @@
               return refnum;
         }
         
-        proxyError(Seq.Ref ref) { this.ref = ref; }
+        proxyError(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native void err() throws Exception;
     }
@@ -172,7 +172,7 @@
               return refnum;
         }
         
-        proxyI(Seq.Ref ref) { this.ref = ref; }
+        proxyI(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native int rand();
     }
@@ -185,7 +185,7 @@
               return refnum;
         }
         
-        proxyI1(Seq.Ref ref) { this.ref = ref; }
+        proxyI1(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native void j();
     }
@@ -198,7 +198,7 @@
               return refnum;
         }
         
-        proxyI2(Seq.Ref ref) { this.ref = ref; }
+        proxyI2(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native void g();
     }
@@ -211,7 +211,7 @@
               return refnum;
         }
         
-        proxyI3(Seq.Ref ref) { this.ref = ref; }
+        proxyI3(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native I1 f();
     }
@@ -224,7 +224,7 @@
               return refnum;
         }
         
-        proxyInterfaces(Seq.Ref ref) { this.ref = ref; }
+        proxyInterfaces(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native void someMethod();
     }
@@ -237,7 +237,7 @@
               return refnum;
         }
         
-        proxyLargerI(Seq.Ref ref) { this.ref = ref; }
+        proxyLargerI(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native void anotherFunc();
         public native int rand();
@@ -251,7 +251,7 @@
               return refnum;
         }
         
-        proxySameI(Seq.Ref ref) { this.ref = ref; }
+        proxySameI(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native int rand();
     }
@@ -264,7 +264,7 @@
               return refnum;
         }
         
-        proxyWithParam(Seq.Ref ref) { this.ref = ref; }
+        proxyWithParam(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native void hasParam(boolean p0);
     }
diff --git a/bind/testdata/issue10788.java.c.golden b/bind/testdata/issue10788.java.c.golden
index 7176a4d..c28be81 100644
--- a/bind/testdata/issue10788.java.c.golden
+++ b/bind/testdata/issue10788.java.c.golden
@@ -21,20 +21,19 @@
     jclass clazz;
     clazz = (*env)->FindClass(env, "issue10788/TestStruct");
     proxy_class_issue10788_TestStruct = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_issue10788_TestStruct_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_issue10788_TestStruct_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "issue10788/Issue10788$proxyTestInterface");
     proxy_class_issue10788_TestInterface = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_issue10788_TestInterface_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_issue10788_TestInterface_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "issue10788/TestInterface");
     mid_TestInterface_DoSomeWork = (*env)->GetMethodID(env, clazz, "doSomeWork", "(Lissue10788/TestStruct;)V");
     mid_TestInterface_MultipleUnnamedParams = (*env)->GetMethodID(env, clazz, "multipleUnnamedParams", "(JLjava/lang/String;J)V");
     
 }
 
-JNIEXPORT jobject JNICALL
+JNIEXPORT jint JNICALL
 Java_issue10788_TestStruct__1_1New(JNIEnv *env, jclass clazz) {
-    int32_t refnum = new_issue10788_TestStruct();
-    return go_seq_from_refnum(env, refnum, NULL, NULL);
+    return new_issue10788_TestStruct();
 }
 
 JNIEXPORT void JNICALL
diff --git a/bind/testdata/issue10788.java.golden b/bind/testdata/issue10788.java.golden
index 75ea43d..7b7f4c4 100644
--- a/bind/testdata/issue10788.java.golden
+++ b/bind/testdata/issue10788.java.golden
@@ -17,11 +17,11 @@
           return refnum;
     }
     
-    TestStruct(Seq.Ref ref) { this.ref = ref; }
+    TestStruct(int refnum) { this.ref = Seq.trackGoRef(refnum); }
     
-    public TestStruct() { this.ref = __New(); }
+    public TestStruct() { this.ref = Seq.trackGoRef(__New()); }
     
-    private static native Seq.Ref __New();
+    private static native int __New();
     
     public final native String getValue();
     public final native void setValue(String v);
@@ -99,7 +99,7 @@
               return refnum;
         }
         
-        proxyTestInterface(Seq.Ref ref) { this.ref = ref; }
+        proxyTestInterface(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native void doSomeWork(TestStruct s);
         public native void multipleUnnamedParams(long p0, String p1, long p2);
diff --git a/bind/testdata/issue12328.java.c.golden b/bind/testdata/issue12328.java.c.golden
index de835cf..7c27e74 100644
--- a/bind/testdata/issue12328.java.c.golden
+++ b/bind/testdata/issue12328.java.c.golden
@@ -17,13 +17,12 @@
     jclass clazz;
     clazz = (*env)->FindClass(env, "issue12328/T");
     proxy_class_issue12328_T = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_issue12328_T_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_issue12328_T_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
 }
 
-JNIEXPORT jobject JNICALL
+JNIEXPORT jint JNICALL
 Java_issue12328_T__1_1New(JNIEnv *env, jclass clazz) {
-    int32_t refnum = new_issue12328_T();
-    return go_seq_from_refnum(env, refnum, NULL, NULL);
+    return new_issue12328_T();
 }
 
 JNIEXPORT void JNICALL
diff --git a/bind/testdata/issue12328.java.golden b/bind/testdata/issue12328.java.golden
index db4d3da..1e69c1f 100644
--- a/bind/testdata/issue12328.java.golden
+++ b/bind/testdata/issue12328.java.golden
@@ -17,11 +17,11 @@
           return refnum;
     }
     
-    T(Seq.Ref ref) { this.ref = ref; }
+    T(int refnum) { this.ref = Seq.trackGoRef(refnum); }
     
-    public T() { this.ref = __New(); }
+    public T() { this.ref = Seq.trackGoRef(__New()); }
     
-    private static native Seq.Ref __New();
+    private static native int __New();
     
     public final native java.lang.Exception getErr();
     public final native void setErr(java.lang.Exception v);
diff --git a/bind/testdata/issue12403.java.c.golden b/bind/testdata/issue12403.java.c.golden
index d9c9ce2..846473c 100644
--- a/bind/testdata/issue12403.java.c.golden
+++ b/bind/testdata/issue12403.java.c.golden
@@ -19,7 +19,7 @@
     jclass clazz;
     clazz = (*env)->FindClass(env, "issue12403/Issue12403$proxyParsable");
     proxy_class_issue12403_Parsable = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_issue12403_Parsable_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_issue12403_Parsable_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "issue12403/Parsable");
     mid_Parsable_FromJSON = (*env)->GetMethodID(env, clazz, "fromJSON", "(Ljava/lang/String;)Ljava/lang/String;");
     mid_Parsable_ToJSON = (*env)->GetMethodID(env, clazz, "toJSON", "()Ljava/lang/String;");
diff --git a/bind/testdata/issue12403.java.golden b/bind/testdata/issue12403.java.golden
index 290ef26..ec3548b 100644
--- a/bind/testdata/issue12403.java.golden
+++ b/bind/testdata/issue12403.java.golden
@@ -42,7 +42,7 @@
               return refnum;
         }
         
-        proxyParsable(Seq.Ref ref) { this.ref = ref; }
+        proxyParsable(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native String fromJSON(String jstr);
         public native String toJSON() throws Exception;
diff --git a/bind/testdata/java.java.c.golden b/bind/testdata/java.java.c.golden
index 607b5a9..99b5e7c 100644
--- a/bind/testdata/java.java.c.golden
+++ b/bind/testdata/java.java.c.golden
@@ -162,30 +162,30 @@
     jclass clazz;
     clazz = (*env)->FindClass(env, "java/Java$proxyF");
     proxy_class_java_F = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_java_F_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_java_F_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "java/F");
     mid_F_ToString = (*env)->GetMethodID(env, clazz, "toString", "()Ljava/lang/String;");
     
     clazz = (*env)->FindClass(env, "java/Java$proxyL");
     proxy_class_java_L = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_java_L_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_java_L_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "java/L");
     mid_L_ToString = (*env)->GetMethodID(env, clazz, "toString", "()Ljava/lang/String;");
     
     clazz = (*env)->FindClass(env, "java/Java$proxyO");
     proxy_class_java_O = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_java_O_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_java_O_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "java/O");
     mid_O_ToString = (*env)->GetMethodID(env, clazz, "toString", "()Ljava/lang/String;");
     
     clazz = (*env)->FindClass(env, "java/Java$proxyR");
     proxy_class_java_R = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_java_R_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_java_R_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "java/R");
     
     clazz = (*env)->FindClass(env, "java/Java$proxyS");
     proxy_class_java_S = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_java_S_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_java_S_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "java/S");
     mid_S_ToString = (*env)->GetMethodID(env, clazz, "toString", "()Ljava/lang/String;");
     
diff --git a/bind/testdata/java.java.golden b/bind/testdata/java.java.golden
index 22a2ec5..0042c9c 100644
--- a/bind/testdata/java.java.golden
+++ b/bind/testdata/java.java.golden
@@ -92,7 +92,7 @@
               return refnum;
         }
         
-        proxyF(Seq.Ref ref) { this.ref = ref; }
+        proxyF(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native String toString();
     }
@@ -105,7 +105,7 @@
               return refnum;
         }
         
-        proxyL(Seq.Ref ref) { this.ref = ref; }
+        proxyL(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native String toString();
     }
@@ -118,7 +118,7 @@
               return refnum;
         }
         
-        proxyO(Seq.Ref ref) { this.ref = ref; }
+        proxyO(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native String toString();
     }
@@ -131,7 +131,7 @@
               return refnum;
         }
         
-        proxyR(Seq.Ref ref) { this.ref = ref; }
+        proxyR(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
     }
     private static final class proxyS implements Seq.Proxy, S {
@@ -143,7 +143,7 @@
               return refnum;
         }
         
-        proxyS(Seq.Ref ref) { this.ref = ref; }
+        proxyS(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native String toString();
     }
diff --git a/bind/testdata/keywords.java.c.golden b/bind/testdata/keywords.java.c.golden
index 933410b..88571de 100644
--- a/bind/testdata/keywords.java.c.golden
+++ b/bind/testdata/keywords.java.c.golden
@@ -72,7 +72,7 @@
     jclass clazz;
     clazz = (*env)->FindClass(env, "keywords/Keywords$proxyKeywordCaller");
     proxy_class_keywords_KeywordCaller = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_keywords_KeywordCaller_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_keywords_KeywordCaller_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "keywords/KeywordCaller");
     mid_KeywordCaller_Abstract = (*env)->GetMethodID(env, clazz, "abstract_", "()V");
     mid_KeywordCaller_Assert = (*env)->GetMethodID(env, clazz, "assert_", "()V");
diff --git a/bind/testdata/keywords.java.golden b/bind/testdata/keywords.java.golden
index 9839bfe..11e056a 100644
--- a/bind/testdata/keywords.java.golden
+++ b/bind/testdata/keywords.java.golden
@@ -95,7 +95,7 @@
               return refnum;
         }
         
-        proxyKeywordCaller(Seq.Ref ref) { this.ref = ref; }
+        proxyKeywordCaller(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native void abstract_();
         public native void assert_();
diff --git a/bind/testdata/structs.java.c.golden b/bind/testdata/structs.java.c.golden
index 0934a11..5a88adf 100644
--- a/bind/testdata/structs.java.c.golden
+++ b/bind/testdata/structs.java.c.golden
@@ -24,16 +24,16 @@
     jclass clazz;
     clazz = (*env)->FindClass(env, "structs/S");
     proxy_class_structs_S = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_structs_S_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_structs_S_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "structs/S2");
     proxy_class_structs_S2 = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_structs_S2_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_structs_S2_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "structs/Structs_");
     proxy_class_structs_Structs = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_structs_Structs_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_structs_Structs_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "structs/Structs$proxyI");
     proxy_class_structs_I = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_structs_I_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_structs_I_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "structs/I");
     mid_I_M = (*env)->GetMethodID(env, clazz, "m", "()V");
     
@@ -57,10 +57,9 @@
     return _r0;
 }
 
-JNIEXPORT jobject JNICALL
+JNIEXPORT jint JNICALL
 Java_structs_S__1_1New(JNIEnv *env, jclass clazz) {
-    int32_t refnum = new_structs_S();
-    return go_seq_from_refnum(env, refnum, NULL, NULL);
+    return new_structs_S();
 }
 
 JNIEXPORT jobject JNICALL
@@ -111,10 +110,9 @@
     return _r0;
 }
 
-JNIEXPORT jobject JNICALL
+JNIEXPORT jint JNICALL
 Java_structs_S2__1_1New(JNIEnv *env, jclass clazz) {
-    int32_t refnum = new_structs_S2();
-    return go_seq_from_refnum(env, refnum, NULL, NULL);
+    return new_structs_S2();
 }
 
 JNIEXPORT void JNICALL
@@ -131,10 +129,9 @@
     return _r0;
 }
 
-JNIEXPORT jobject JNICALL
+JNIEXPORT jint JNICALL
 Java_structs_Structs_1__1_1New(JNIEnv *env, jclass clazz) {
-    int32_t refnum = new_structs_Structs();
-    return go_seq_from_refnum(env, refnum, NULL, NULL);
+    return new_structs_Structs();
 }
 
 JNIEXPORT void JNICALL
diff --git a/bind/testdata/structs.java.golden b/bind/testdata/structs.java.golden
index e1aed3f..e8d01ca 100644
--- a/bind/testdata/structs.java.golden
+++ b/bind/testdata/structs.java.golden
@@ -17,11 +17,11 @@
           return refnum;
     }
     
-    S(Seq.Ref ref) { this.ref = ref; }
+    S(int refnum) { this.ref = Seq.trackGoRef(refnum); }
     
-    public S() { this.ref = __New(); }
+    public S() { this.ref = Seq.trackGoRef(__New()); }
     
-    private static native Seq.Ref __New();
+    private static native int __New();
     
     public final native double getX();
     public final native void setX(double v);
@@ -81,11 +81,11 @@
           return refnum;
     }
     
-    S2(Seq.Ref ref) { this.ref = ref; }
+    S2(int refnum) { this.ref = Seq.trackGoRef(refnum); }
     
-    public S2() { this.ref = __New(); }
+    public S2() { this.ref = Seq.trackGoRef(__New()); }
     
-    private static native Seq.Ref __New();
+    private static native int __New();
     
     public native void m();
     public native String string();
@@ -125,11 +125,11 @@
           return refnum;
     }
     
-    Structs_(Seq.Ref ref) { this.ref = ref; }
+    Structs_(int refnum) { this.ref = Seq.trackGoRef(refnum); }
     
-    public Structs_() { this.ref = __New(); }
+    public Structs_() { this.ref = Seq.trackGoRef(__New()); }
     
-    private static native Seq.Ref __New();
+    private static native int __New();
     
     public native void m();
     @Override public boolean equals(Object o) {
@@ -194,7 +194,7 @@
               return refnum;
         }
         
-        proxyI(Seq.Ref ref) { this.ref = ref; }
+        proxyI(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         public native void m();
     }
diff --git a/bind/testdata/underscores.java.c.golden b/bind/testdata/underscores.java.c.golden
index a9d18f7..c617f01 100644
--- a/bind/testdata/underscores.java.c.golden
+++ b/bind/testdata/underscores.java.c.golden
@@ -17,7 +17,7 @@
     jclass clazz;
     clazz = (*env)->FindClass(env, "underscore_pkg/Underscore_struct");
     proxy_class_underscore_pkg_Underscore_struct = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_underscore_pkg_Underscore_struct_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_underscore_pkg_Underscore_struct_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
 }
 
 JNIEXPORT void JNICALL
@@ -25,10 +25,9 @@
     proxyunderscore_pkg__Underscore_func();
 }
 
-JNIEXPORT jobject JNICALL
+JNIEXPORT jint JNICALL
 Java_underscore_1pkg_Underscore_1struct__1_1New(JNIEnv *env, jclass clazz) {
-    int32_t refnum = new_underscore_pkg_Underscore_struct();
-    return go_seq_from_refnum(env, refnum, NULL, NULL);
+    return new_underscore_pkg_Underscore_struct();
 }
 
 JNIEXPORT void JNICALL
diff --git a/bind/testdata/underscores.java.golden b/bind/testdata/underscores.java.golden
index fa1f8da..eae8f31 100644
--- a/bind/testdata/underscores.java.golden
+++ b/bind/testdata/underscores.java.golden
@@ -17,11 +17,11 @@
           return refnum;
     }
     
-    Underscore_struct(Seq.Ref ref) { this.ref = ref; }
+    Underscore_struct(int refnum) { this.ref = Seq.trackGoRef(refnum); }
     
-    public Underscore_struct() { this.ref = __New(); }
+    public Underscore_struct() { this.ref = Seq.trackGoRef(__New()); }
     
-    private static native Seq.Ref __New();
+    private static native int __New();
     
     public final native String getUnderscore_field();
     public final native void setUnderscore_field(String v);
diff --git a/bind/testdata/universe.java.c.golden b/bind/testdata/universe.java.c.golden
index 29ce3cd..71a481a 100644
--- a/bind/testdata/universe.java.c.golden
+++ b/bind/testdata/universe.java.c.golden
@@ -18,7 +18,7 @@
     jclass clazz;
     clazz = (*env)->FindClass(env, "go/Universe$proxyerror");
     proxy_class__error = (*env)->NewGlobalRef(env, clazz);
-    proxy_class__error_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class__error_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "java/lang/Throwable");
     mid_error_Error = (*env)->GetMethodID(env, clazz, "getMessage", "()Ljava/lang/String;");
 }
diff --git a/bind/testdata/universe.java.golden b/bind/testdata/universe.java.golden
index f01d6b2..1b60067 100644
--- a/bind/testdata/universe.java.golden
+++ b/bind/testdata/universe.java.golden
@@ -41,7 +41,7 @@
               return refnum;
         }
         
-        proxyerror(Seq.Ref ref) { this.ref = ref; }
+        proxyerror(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
         @Override public String getMessage() { return error(); }
         
diff --git a/bind/testdata/vars.java.c.golden b/bind/testdata/vars.java.c.golden
index ff5e77c..aacc9cd 100644
--- a/bind/testdata/vars.java.c.golden
+++ b/bind/testdata/vars.java.c.golden
@@ -19,18 +19,17 @@
     jclass clazz;
     clazz = (*env)->FindClass(env, "vars/S");
     proxy_class_vars_S = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_vars_S_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_vars_S_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "vars/Vars$proxyI");
     proxy_class_vars_I = (*env)->NewGlobalRef(env, clazz);
-    proxy_class_vars_I_cons = (*env)->GetMethodID(env, clazz, "<init>", "(Lgo/Seq$Ref;)V");
+    proxy_class_vars_I_cons = (*env)->GetMethodID(env, clazz, "<init>", "(I)V");
     clazz = (*env)->FindClass(env, "vars/I");
     
 }
 
-JNIEXPORT jobject JNICALL
+JNIEXPORT jint JNICALL
 Java_vars_S__1_1New(JNIEnv *env, jclass clazz) {
-    int32_t refnum = new_vars_S();
-    return go_seq_from_refnum(env, refnum, NULL, NULL);
+    return new_vars_S();
 }
 
 JNIEXPORT void JNICALL
diff --git a/bind/testdata/vars.java.golden b/bind/testdata/vars.java.golden
index 2e6b49d..4161af7 100644
--- a/bind/testdata/vars.java.golden
+++ b/bind/testdata/vars.java.golden
@@ -17,11 +17,11 @@
           return refnum;
     }
     
-    S(Seq.Ref ref) { this.ref = ref; }
+    S(int refnum) { this.ref = Seq.trackGoRef(refnum); }
     
-    public S() { this.ref = __New(); }
+    public S() { this.ref = Seq.trackGoRef(__New()); }
     
-    private static native Seq.Ref __New();
+    private static native int __New();
     
     @Override public boolean equals(Object o) {
         if (o == null || !(o instanceof S)) {
@@ -84,7 +84,7 @@
               return refnum;
         }
         
-        proxyI(Seq.Ref ref) { this.ref = ref; }
+        proxyI(int refnum) { this.ref = Seq.trackGoRef(refnum); }
         
     }