diff --git a/incremental-cj/runtime/src/core/CallsiteKey.cj b/incremental-cj/runtime/src/core/CallsiteKey.cj
index ec02af08eefae95906ff3c96850b2986dd08a5b6..45de6b1ba09b95d5704dbf2bd183dc2890e19ff7 100644
--- a/incremental-cj/runtime/src/core/CallsiteKey.cj
+++ b/incremental-cj/runtime/src/core/CallsiteKey.cj
@@ -14,7 +14,7 @@
  */
 package KoalaRuntime.core
 
-import std.format.*
+import std.convert.*
 
 public type CallsiteKey = UInt64
 
diff --git a/incremental-cj/runtime/src/core/Dependency.cj b/incremental-cj/runtime/src/core/Dependency.cj
index 55b9821ef9266623acca478582a2466fe3713fd1..fa6e7202947331d7ed4a17608f89f6871d7ee857 100644
--- a/incremental-cj/runtime/src/core/Dependency.cj
+++ b/incremental-cj/runtime/src/core/Dependency.cj
@@ -69,11 +69,11 @@ public class Dependencies {
                     return
                 }
                 if (let Some(dependencies) <- this.dependencies) {
-                    dependencies.put(dependency)
+                    dependencies.add(dependency)
                 } else {
                     let set = HashSet<Dependency>()
-                    set.put(latest)
-                    set.put(dependency)
+                    set.add(latest)
+                    set.add(dependency)
                     this.dependencies = set
                 }
             }
diff --git a/incremental-cj/runtime/src/core/ScopeImpl.cj b/incremental-cj/runtime/src/core/ScopeImpl.cj
index f9fdada1a461f8037f1ea454814d4f3242d1fd38..160c3225ae4dc579a4027f7984883339c942227d 100644
--- a/incremental-cj/runtime/src/core/ScopeImpl.cj
+++ b/incremental-cj/runtime/src/core/ScopeImpl.cj
@@ -174,7 +174,7 @@ abstract class ManagedScope <: Dependency & TreeNode<ManagedScope> & Equatable<M
 
     func addCreatedState(state: UniqueObject): Unit {
         if (let Some(list) <- this.createdStates) {
-            list.append(state)
+            list.add(state)
         } else {
             this.createdStates = ArrayList<UniqueObject>([state])
         }
@@ -182,7 +182,7 @@ abstract class ManagedScope <: Dependency & TreeNode<ManagedScope> & Equatable<M
 
     func setNamedState(name: String, state: UniqueObject): Unit {
         if (let Some(map) <- this.namedStates) {
-            map.put(name, state)
+            map.add(name, state)
         } else {
             this.namedStates = HashMap<String, UniqueObject>([(name, state)])
         }
diff --git a/incremental-cj/runtime/src/core/StateManager.cj b/incremental-cj/runtime/src/core/StateManager.cj
index a4ad2207e6140f6e65c06a92d71b9fc2e1dd3cde..993b060286f9c0cdc78e92879a9aff500461c2ea 100644
--- a/incremental-cj/runtime/src/core/StateManager.cj
+++ b/incremental-cj/runtime/src/core/StateManager.cj
@@ -29,7 +29,7 @@ let scheduledCallbacks = ArrayList<() -> Unit>()
  * @param callback - a function to perform between recompositions
  */
 public func scheduleCallback(callback: () -> Unit): Unit {
-    scheduledCallbacks.append(callback)
+    scheduledCallbacks.add(callback)
 }
 
 /**
@@ -93,7 +93,7 @@ public class GlobalStateManager {
     }
 
     static func addCreatedState(state: AbstractState): Unit {
-        createdStates.put(state)
+        createdStates.add(state)
         if (!state.global) {
             currentScope?.addCreatedState(state)
         }
@@ -117,7 +117,7 @@ public class GlobalStateManager {
     }
 
     static func addDirtyScope(scope: ManagedScope): Unit {
-        dirtyScopes.put(scope)
+        dirtyScopes.add(scope)
     }
 
     static func checkForStateDisposing(): Unit {
@@ -247,7 +247,7 @@ public class GlobalStateManager {
             stateCreating = None
             let state = StateImpl<Value>(initial, global, tracker, name)
             if (global) {
-                namedStates.put(name, state)
+                namedStates.add(name, state)
             } else if (let Some(scope) <- currentScope) {
                 scope.setNamedState(name, state)
             }
diff --git a/incremental-cj/runtime/src/memoize/visitor.cj b/incremental-cj/runtime/src/memoize/visitor.cj
index 6181167f37c039cd204d240934dff8fe640d3ccb..eebbfa23beb43bc5a41b31b0b9e4d2e160a75b6e 100644
--- a/incremental-cj/runtime/src/memoize/visitor.cj
+++ b/incremental-cj/runtime/src/memoize/visitor.cj
@@ -46,8 +46,8 @@ open class MemoVisitor <: Visitor {
                 let varValue = Token(IDENTIFIER, param.identifier.value)
                 let varDecl = VarDecl(quote(let $(varName) = getParameter(__memo_scope, $(count), $(varValue), $(param.identifier.value))))
 
-                memoizedParamsNames.append(param.identifier.value)
-                memoizedParams.append(varDecl)
+                memoizedParamsNames.add(param.identifier.value)
+                memoizedParams.add(varDecl)
                 count++
             }
         }
@@ -61,8 +61,8 @@ open class MemoVisitor <: Visitor {
             let varValue = Token(IDENTIFIER, param.identifier.value)
             let varDecl = VarDecl(quote(let $(varName) = getParameter(__memo_scope, $(count), $(varValue), $(param.identifier.value))))
 
-            memoizedParamsNames.append(param.identifier.value)
-            memoizedParams.append(varDecl)
+            memoizedParamsNames.add(param.identifier.value)
+            memoizedParams.add(varDecl)
             count++
         }
         return memoizedParams
@@ -98,22 +98,22 @@ class MemoFuncVisitor <: MemoVisitor {
         let memoizedParams = memoizeParams(funcDecl)
 
         funcDecl.block.nodes = ArrayList()
-        funcDecl.block.nodes.append(VarDecl(quote(let __memo_key = getCallsiteKey())))
-        funcDecl.block.nodes.append(
+        funcDecl.block.nodes.add(VarDecl(quote(let __memo_key = getCallsiteKey())))
+        funcDecl.block.nodes.add(
             VarDecl(
             quote(let __memo_scope = getMemoScope < $(funcType) >(__memo_key, $(memoizedParams.size)))
         ))
         
         for (memoizedParam in memoizedParams) {
-            funcDecl.block.nodes.append(memoizedParam)
+            funcDecl.block.nodes.add(memoizedParam)
         }
         for (param in memoizedParamsNames) {
             let varGetterName = Token(IDENTIFIER, "__memo_param_value_" + param)
             let memoParam = Token(IDENTIFIER, "__memo_param_" + param)
             let varGetter = VarDecl(quote(let $(varGetterName) = $(memoParam).getValue()))
-            funcDecl.block.nodes.append(varGetter)
+            funcDecl.block.nodes.add(varGetter)
         }
-        funcDecl.block.nodes.append(
+        funcDecl.block.nodes.add(
             IfExpr(
             quote(if (__memo_scope.isUnchanged()) {
                         return __memo_scope.getCached()
@@ -124,11 +124,11 @@ class MemoFuncVisitor <: MemoVisitor {
             blockNode.traverse(LambdaVisitor(this.memoizedParamsNames))
             blockNode.traverse(RefExprVisitor(this.memoizedParamsNames))
             blockNode.traverse(ReturnVisitor())
-            funcDecl.block.nodes.append(blockNode)
+            funcDecl.block.nodes.add(blockNode)
         }
         let lastNode = funcDecl.block.nodes[funcDecl.block.nodes.size - 1]
         if (!(lastNode is ReturnExpr) && quote($(funcType)).toTokens()[0].kind == Token(UNIT).kind) {
-            funcDecl.block.nodes.append(parseExpr(quote(return __memo_scope.recache(MEMO_UNIT))))
+            funcDecl.block.nodes.add(parseExpr(quote(return __memo_scope.recache(MEMO_UNIT))))
         }
         breakTraverse()
     }
@@ -147,15 +147,15 @@ class LambdaVisitor <: MemoVisitor {
             let varGetterName = Token(IDENTIFIER, "__memo_param_value_" + param)
             let memoParam = Token(IDENTIFIER, "__memo_param_" + param)
             let varGetter = VarDecl(quote(let $(varGetterName) = $(memoParam).getValue()))
-            lambdaExpr.nodes.append(varGetter)
+            lambdaExpr.nodes.add(varGetter)
         }
         for (blockNode in blockNodes) {
             blockNode.traverse(RefExprVisitor(memoizedParamsNames))
-            lambdaExpr.nodes.append(blockNode)
+            lambdaExpr.nodes.add(blockNode)
         }
         // let lastNode = lambdaExpr.nodes[lambdaExpr.nodes.size - 1]
         // if (!(lastNode is ReturnExpr)) {
-        //     lambdaExpr.nodes.append(parseExpr(quote(return)))
+        //     lambdaExpr.nodes.add(parseExpr(quote(return)))
         // }
         // breakTraverse()
     }
@@ -177,22 +177,22 @@ class MemoLambdaVisitor <: MemoVisitor {
         let blockNodes = lambdaExpr.nodes
         lambdaExpr.nodes = ArrayList()
 
-        lambdaExpr.nodes.append(VarDecl(quote(let __memo_key = getCallsiteKey())))
-        lambdaExpr.nodes.append(
+        lambdaExpr.nodes.add(VarDecl(quote(let __memo_key = getCallsiteKey())))
+        lambdaExpr.nodes.add(
             VarDecl(
             quote(let __memo_scope = getMemoScope < Unit >(__memo_key, $(memoizedParams.size)))
             ))
             
         for (memoizedParam in memoizedParams) {
-            lambdaExpr.nodes.append(memoizedParam)
+            lambdaExpr.nodes.add(memoizedParam)
         }
         for (param in memoizedParamsNames) {
             let varGetterName = Token(IDENTIFIER, "__memo_param_value_" + param)
             let memoParam = Token(IDENTIFIER, "__memo_param_" + param)
             let varGetter = VarDecl(quote(let $(varGetterName) = $(memoParam).getValue()))
-            lambdaExpr.nodes.append(varGetter)
+            lambdaExpr.nodes.add(varGetter)
         }
-        lambdaExpr.nodes.append(
+        lambdaExpr.nodes.add(
             IfExpr(
             quote(if (__memo_scope.isUnchanged()) {
                         return __memo_scope.getCached()
@@ -202,11 +202,11 @@ class MemoLambdaVisitor <: MemoVisitor {
             blockNode.traverse(LambdaVisitor(this.memoizedParamsNames))
             blockNode.traverse(RefExprVisitor(this.memoizedParamsNames))
             blockNode.traverse(ReturnVisitor())
-            lambdaExpr.nodes.append(blockNode)
+            lambdaExpr.nodes.add(blockNode)
         }
         let lastNode = lambdaExpr.nodes[lambdaExpr.nodes.size - 1]
         if (!(lastNode is ReturnExpr)) {
-            lambdaExpr.nodes.append(parseExpr(quote(return __memo_scope.recache(MEMO_UNIT))))
+            lambdaExpr.nodes.add(parseExpr(quote(return __memo_scope.recache(MEMO_UNIT))))
         }
         breakTraverse()
     }
diff --git a/interop/src/cangjie/ResourceManager.cj b/interop/src/cangjie/ResourceManager.cj
index 666f8564de430d702b749f96d340b0ba35e2b1c4..d2e589d5f6058a8dd469da300134321754f4aba0 100644
--- a/interop/src/cangjie/ResourceManager.cj
+++ b/interop/src/cangjie/ResourceManager.cj
@@ -65,7 +65,7 @@ public class ResourceHolder {
     public func registerAndHold(resource: Any): ResourceId {
         ResourceHolder.nextResourceId += 1
         let resourceId = ResourceHolder.nextResourceId
-        this.resources.put(resourceId, ResourceInfo(resource, resourceId))
+        this.resources.add(resourceId, ResourceInfo(resource, resourceId))
         return resourceId
     }
 
diff --git a/interop/src/cangjie/SerializerBase.cj b/interop/src/cangjie/SerializerBase.cj
index cb8783343ed58e90841e1c5f6c7a6905a1324ff0..612d63e9a2f3ec2e7354f20285bfa3b7487eda82 100644
--- a/interop/src/cangjie/SerializerBase.cj
+++ b/interop/src/cangjie/SerializerBase.cj
@@ -96,7 +96,7 @@ public open class SerializerBase {
             let resizedSize = max(minSize, Int64(round(3.0 * Float64(buffSize) / 2.0)))
             var resizedBuffer =  ArrayList<UInt8>(this.buffer)
             while (resizedBuffer.size < resizedSize) {
-                resizedBuffer.append(0)
+                resizedBuffer.add(0)
             }
             this.buffer = resizedBuffer
         }
@@ -110,7 +110,7 @@ public open class SerializerBase {
     private var heldResources: ArrayList<ResourceId> = ArrayList<ResourceId>()
     public func holdAndWriteCallback(callback: Any): ResourceId {
         let resourceId = ResourceHolder.instance().registerAndHold(callback)
-        this.heldResources.append(resourceId)
+        this.heldResources.add(resourceId)
         this.writeInt32(resourceId)
         this.writePointer(0)
         this.writePointer(0)
@@ -120,7 +120,7 @@ public open class SerializerBase {
     }
     public func holdAndWriteCallback(callback: Any, hold: KPointer, release: KPointer, call: KPointer, callSync: KPointer): ResourceId {
         let resourceId = ResourceHolder.instance().registerAndHold(callback)
-        this.heldResources.append(resourceId)
+        this.heldResources.add(resourceId)
         this.writeInt32(resourceId)
         this.writePointer(hold)
         this.writePointer(release)