diff --git a/scripthaus.md b/scripthaus.md
index f3c9caf9..1a8dd7bd 100644
--- a/scripthaus.md
+++ b/scripthaus.md
@@ -11,3 +11,9 @@ node_modules/.bin/webpack --watch --config webpack.dev.js
 # @scripthaus cd :current
 node_modules/.bin/webpack-dev-server --config webpack.dev.js --host 0.0.0.0
 ```
+
+```bash
+# @scripthaus command typecheck
+# @scripthaus cd :current
+node_modules/.bin/tsc --jsx preserve --noEmit --esModuleInterop --target ES5 --experimentalDecorators --downlevelIteration src/sh2.ts
+```
diff --git a/src/main.tsx b/src/main.tsx
index aa18d163..9d0299f0 100644
--- a/src/main.tsx
+++ b/src/main.tsx
@@ -3,11 +3,12 @@ import * as mobxReact from "mobx-react";
 import * as mobx from "mobx";
 import {sprintf} from "sprintf-js";
 import {boundMethod} from "autobind-decorator";
-import * as dayjs from 'dayjs'
+import dayjs from 'dayjs'
 import {If, For, When, Otherwise, Choose} from "tsx-control-statements/components";
 import cn from "classnames"
 import {TermWrap} from "./term";
-import {getDefaultSession, getLineId} from "./session";
+import {getDefaultSession, getLineId, Session} from "./session";
+import type {LineType} from "./session";
 import localizedFormat from 'dayjs/plugin/localizedFormat';
 
 dayjs.extend(localizedFormat)
@@ -70,7 +71,7 @@ class LineText extends React.Component<{line : LineType, session : Session}, {}>
 }
 
 @mobxReact.observer
-class LineCmd extends React.Component<{line : LineType, session : Session, changeSizeCallback : () => void}, {}> {
+class LineCmd extends React.Component<{line : LineType, session : Session, changeSizeCallback? : (term : TermWrap) => void}, {}> {
     constructor(props) {
         super(props);
     }
@@ -127,7 +128,7 @@ class LineCmd extends React.Component<{line : LineType, session : Session, chang
         let termSize = termWrap.getSize();
         let formattedTime = getLineDateStr(line.ts);
         let cellHeightPx = 17;
-        let totalHeight = cellHeightPx * termWrap.usedRows;
+        let totalHeight = cellHeightPx * termWrap.usedRows.get();
         return (
             <div className="line line-cmd" id={"line-" + getLineId(line)}>
                 <div className={cn("avatar",{"num4": lineid.length == 4}, {"num5": lineid.length >= 5}, {"running": running})}>
@@ -161,7 +162,7 @@ class LineCmd extends React.Component<{line : LineType, session : Session, chang
 }
 
 @mobxReact.observer
-class Line extends React.Component<{line : LineType, session : Session}, {}> {
+class Line extends React.Component<{line : LineType, session : Session, changeSizeCallback? : (term : TermWrap) => void}, {}> {
     render() {
         let line = this.props.line;
         if (line.linetype == "text") {
@@ -273,7 +274,7 @@ class CmdInput extends React.Component<{session : Session, windowid : string}, {
                         <div className="button is-static">mike@local</div>
                     </div>
                     <div className="control cmd-input-control is-expanded">
-                        <textarea value={curLine} onKeyDown={this.onKeyDown} onChange={this.onChange} className="input" type="text"></textarea>
+                        <textarea value={curLine} onKeyDown={this.onKeyDown} onChange={this.onChange} className="input"></textarea>
                     </div>
                     <div className="control cmd-exec">
                         <div onClick={this.doSubmitCmd} className="button">
@@ -289,8 +290,8 @@ class CmdInput extends React.Component<{session : Session, windowid : string}, {
 }
 
 @mobxReact.observer
-class SessionView extends React.Component<{session : SessionType}, {}> {
-    shouldFollow : IObservableValue<boolean> = mobx.observable.box(true);
+class SessionView extends React.Component<{session : Session}, {}> {
+    shouldFollow : mobx.IObservableValue<boolean> = mobx.observable.box(true);
 
     @boundMethod
     scrollHandler(event : any) {
@@ -325,6 +326,7 @@ class SessionView extends React.Component<{session : SessionType}, {}> {
             return <div className="session-view">(loading)</div>;
         }
         let idx = 0;
+        let line : LineType = null;
         return (
             <div className="session-view">
                 <div className="lines" onScroll={this.scrollHandler}>
diff --git a/src/session.ts b/src/session.ts
index f953b548..86e504b5 100644
--- a/src/session.ts
+++ b/src/session.ts
@@ -49,7 +49,8 @@ type WindowDataType = {
     windowid : string,
     name : string,
     curremote : string,
-    lines : mobx.IObservableValue<LineType[]>,
+    lines : mobx.IObservableArray<LineType>,
+    linesLoading : mobx.IObservableValue<boolean>,
     version : number,
 };
 
@@ -64,6 +65,9 @@ type SessionDataType = {
     cmds : CmdDataType[],
 };
 
+type CmdDataType = {
+};
+
 class Session {
     sessionId : string;
     name : string;
@@ -112,7 +116,7 @@ class Session {
     }
 
     getCurWindow() : WindowDataType {
-        return this.getWindowById(this.activeWindowId);
+        return this.getWindowById(this.activeWindowId.get());
     }
 
     loadWindowLines(windowid : string) {
@@ -127,7 +131,7 @@ class Session {
         window.linesLoading.set(true);
         
         let usp = new URLSearchParams({sessionid: this.sessionId, windowid: windowid});
-        let url = sprintf("http://localhost:8080/api/get-window-lines?") + usp.toString();
+        let url = new URL(sprintf("http://localhost:8080/api/get-window-lines?") + usp.toString());
         fetch(url).then((resp) => handleJsonFetchResponse(url, resp)).then((data) => {
             mobx.action(() => {
                 window.lines.replace(data.data || []);
@@ -146,15 +150,16 @@ class Session {
 
     submitCommand(windowid : string, commandStr : string) {
         let url = sprintf("http://localhost:8080/api/run-command");
-        let data = {type: "fecmd", sessionid: this.sessionId, windowid: windowid, cmdstr: commandStr, userid: GlobalUser};
+        let data = {type: "fecmd", sessionid: this.sessionId, windowid: windowid, cmdstr: commandStr, userid: GlobalUser, remotestate: null};
         let curWindow = this.getCurWindow();
         if (curWindow == null) {
             throw new Error(sprintf("invalid current window=%s", this.activeWindowId));
         }
-        data.remotestate = this.getWindowCurRemoteData(this.activeWindowId);
-        if (data.remotestate == null) {
-            throw new Error(sprintf("no remotestate found for windowid:%s (remote=%s), cannot submit command", windowid, window.curremote));
+        let rstate = this.getWindowCurRemoteData(this.activeWindowId.get());
+        if (rstate == null) {
+            throw new Error(sprintf("no remotestate found for windowid:%s (remote=%s), cannot submit command", windowid, curWindow.curremote));
         }
+        data.remotestate = rstate;
         fetch(url, {method: "post", body: JSON.stringify(data)}).then((resp) => handleJsonFetchResponse(url, resp)).then((data) => {
             mobx.action(() => {
                 if (data.data != null && data.data.line != null) {
@@ -280,7 +285,7 @@ function initSession() {
     });
     
     let usp = new URLSearchParams({name: "default"});
-    let url = sprintf("http://localhost:8080/api/get-session?") + usp.toString();
+    let url = new URL(sprintf("http://localhost:8080/api/get-session?") + usp.toString());
     fetch(url).then((resp) => handleJsonFetchResponse(url, resp)).then((data) => {
         mobx.action(() => {
             let sdata = data.data;
@@ -307,7 +312,7 @@ function getDefaultSession() : Session {
     return DefaultSession;
 }
 
-window.getDefaultSession = getDefaultSession;
+(window as any).getDefaultSession = getDefaultSession;
 
 export {Session, getDefaultSession, getLineId, initSession};
 export type {LineType, WindowDataType};
diff --git a/src/sh2.ts b/src/sh2.ts
index 5dba839d..fdb4319c 100644
--- a/src/sh2.ts
+++ b/src/sh2.ts
@@ -7,9 +7,10 @@ import {GlobalWS} from "./ws";
 import {v4 as uuidv4} from "uuid";
 import {initSession} from "./session";
 
+// @ts-ignore
 let VERSION = __SHVERSION__;
 
-window.ScriptHausClientId = uuidv4();
+(window as any).ScriptHausClientId = uuidv4();
 
 document.addEventListener("DOMContentLoaded", () => {
     initSession();
diff --git a/src/term.ts b/src/term.ts
index 5fffacd5..8a09b2a2 100644
--- a/src/term.ts
+++ b/src/term.ts
@@ -19,7 +19,7 @@ function loadPtyOut(term : Terminal, sessionId : string, cmdId : string, delayMs
 }
 
 class TermWrap {
-    terminal : Terminal;
+    terminal : any;
     termId : string;
     sessionId : string;
     cmdId : string;
@@ -33,7 +33,7 @@ class TermWrap {
     atRowMax : boolean = false;
     initialized : boolean = false;
     changeSizeCallback : (TermWrap) => void = null;
-    usedRows : number = null;
+    usedRows : mobx.IObservableValue<number> = null;
 
     constructor(sessionId : string, cmdId : string) {
         this.termId = uuidv4();
@@ -109,7 +109,7 @@ class TermWrap {
                 usedRows = i+1;
             }
         }
-        this.usedRows = usedRows;
+        this.usedRows.set(usedRows);
         return;
     }
 
@@ -117,11 +117,11 @@ class TermWrap {
         this.flexRows = true;
         this.maxRows = rows;
         if (!flexRows) {
-            term.resize(rows, cols);
-            setTimeout(() => incRenderVersion(), 10);
+            this.terminal.resize(rows, cols);
+            setTimeout(() => this.incRenderVersion(), 10);
             return;
         }
-        resizeToContent();
+        this.resizeToContent();
     }
 
     getSize() : {rows : number, cols : number} {
diff --git a/src/util.ts b/src/util.ts
index 71b10660..29b3bf10 100644
--- a/src/util.ts
+++ b/src/util.ts
@@ -1,3 +1,5 @@
+import {sprintf} from "sprintf-js";
+
 function fetchJsonData(resp : any, ctErr : boolean) : Promise<any> {
     let contentType = resp.headers.get("Content-Type");
     if (contentType != null && contentType.startsWith("application/json")) {
diff --git a/src/ws.ts b/src/ws.ts
index b5396c10..cf1bda2e 100644
--- a/src/ws.ts
+++ b/src/ws.ts
@@ -2,11 +2,13 @@ import * as mobx from "mobx";
 import {sprintf} from "sprintf-js";
 import {boundMethod} from "autobind-decorator";
 
+declare var window : any;
+
 class WSControl {
     wsConn : any;
     open : mobx.IObservableValue<boolean>;
     opening : boolean = false;
-    reconnectTimes : int = 0;
+    reconnectTimes : number = 0;
     msgQueue : any[] = [];
     reqMap : Record<string, (dataPacket : any) => void> = {};
     
@@ -109,7 +111,7 @@ class WSControl {
             return;
         }
         if (eventData.type == "ping") {
-            this.wsConn.send(JSON.stringify({type: "pong", stime: parseInt(Date.now()/1000)}));
+            this.wsConn.send(JSON.stringify({type: "pong", stime: Date.now()}));
             return;
         }
         if (eventData.type == "pong") {