diff --git a/tools/cli/src/main/java/org/teavm/cli/TeaVMDevServerRunner.java b/tools/cli/src/main/java/org/teavm/cli/TeaVMDevServerRunner.java
index 0298db148..8073ac924 100644
--- a/tools/cli/src/main/java/org/teavm/cli/TeaVMDevServerRunner.java
+++ b/tools/cli/src/main/java/org/teavm/cli/TeaVMDevServerRunner.java
@@ -52,7 +52,7 @@ public final class TeaVMDevServerRunner {
                 .create('f'));
         options.addOption(OptionBuilder
                 .withArgName("classpath")
-                .hasArg()
+                .hasArgs()
                 .withDescription("classpath element (either directory or jar file)")
                 .withLongOpt("classpath")
                 .create('p'));
@@ -66,10 +66,16 @@ public final class TeaVMDevServerRunner {
                 .withArgName("number")
                 .hasArg()
                 .withDescription("port (default is 9090)")
-                .create("port"));
+                .withLongOpt("port")
+                .create());
         options.addOption(OptionBuilder
                 .withDescription("display indicator on web page")
-                .create("indicator"));
+                .withLongOpt("indicator")
+                .create());
+        options.addOption(OptionBuilder
+                .withDescription("automatically reload page when compilation completes")
+                .withLongOpt("auto-reload")
+                .create());
         options.addOption(OptionBuilder
                 .withDescription("display more messages on server log")
                 .withLongOpt("verbose")
@@ -107,6 +113,7 @@ public final class TeaVMDevServerRunner {
         parseOutputOptions();
 
         devServer.setIndicator(commandLine.hasOption("indicator"));
+        devServer.setReloadedAutomatically(commandLine.hasOption("auto-reload"));
         if (commandLine.hasOption("port")) {
             try {
                 devServer.setPort(Integer.parseInt(commandLine.getOptionValue("port")));
diff --git a/tools/core/src/main/java/org/teavm/tooling/util/FileSystemWatcher.java b/tools/core/src/main/java/org/teavm/tooling/util/FileSystemWatcher.java
index 349f73d6a..d37482961 100644
--- a/tools/core/src/main/java/org/teavm/tooling/util/FileSystemWatcher.java
+++ b/tools/core/src/main/java/org/teavm/tooling/util/FileSystemWatcher.java
@@ -159,6 +159,9 @@ public class FileSystemWatcher {
             return Collections.emptyList();
         }
         Path basePath = keysToPath.get(baseKey);
+        if (basePath == null) {
+            return Collections.emptyList();
+        }
         Path path = basePath.resolve((Path) event.context());
         WatchKey key = pathsToKey.get(path);
 
diff --git a/tools/devserver/src/main/java/org/teavm/devserver/CodeServlet.java b/tools/devserver/src/main/java/org/teavm/devserver/CodeServlet.java
index 0b788e5a2..37530efcc 100644
--- a/tools/devserver/src/main/java/org/teavm/devserver/CodeServlet.java
+++ b/tools/devserver/src/main/java/org/teavm/devserver/CodeServlet.java
@@ -75,6 +75,7 @@ public class CodeServlet extends HttpServlet {
     private List<String> sourcePath = new ArrayList<>();
     private TeaVMToolLog log = new EmptyTeaVMToolLog();
     private boolean indicator;
+    private boolean automaticallyReloaded;
     private int port;
 
     private Map<String, Supplier<InputStream>> sourceFileCache = new HashMap<>();
@@ -132,6 +133,10 @@ public class CodeServlet extends HttpServlet {
         this.wsEndpoint = wsEndpoint;
     }
 
+    public void setAutomaticallyReloaded(boolean automaticallyReloaded) {
+        this.automaticallyReloaded = automaticallyReloaded;
+    }
+
     @Override
     protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws IOException {
         String path = req.getPathInfo();
@@ -353,6 +358,9 @@ public class CodeServlet extends HttpServlet {
         log.info("Starting build");
         progressListener.last = 0;
         progressListener.lastTime = System.currentTimeMillis();
+        if (wsEndpoint != null) {
+            wsEndpoint.progress(0);
+        }
         vm.build(buildTarget, fileName);
         addIndicator();
         generateDebug(debugInformationBuilder);
@@ -381,6 +389,7 @@ public class CodeServlet extends HttpServlet {
             script = script.substring(script.indexOf("*/") + 2);
             script = script.replace("WS_PATH", "localhost:" + port + pathToFile + fileName + ".ws");
             script = script.replace("BOOT_FLAG", Boolean.toString(boot));
+            script = script.replace("RELOAD_FLAG", Boolean.toString(automaticallyReloaded));
             script = script.replace("FILE_NAME", "http://localhost:" + port + pathToFile + fileName);
             return script;
         } catch (IOException e) {
@@ -510,7 +519,7 @@ public class CodeServlet extends HttpServlet {
             switch (phase) {
                 case DEPENDENCY_ANALYSIS:
                     start = 0;
-                    end = 500;
+                    end = 400;
                     break;
                 case LINKING:
                     start = 400;
diff --git a/tools/devserver/src/main/java/org/teavm/devserver/CodeWsEndpoint.java b/tools/devserver/src/main/java/org/teavm/devserver/CodeWsEndpoint.java
index 9d2382dea..76bc95151 100644
--- a/tools/devserver/src/main/java/org/teavm/devserver/CodeWsEndpoint.java
+++ b/tools/devserver/src/main/java/org/teavm/devserver/CodeWsEndpoint.java
@@ -23,6 +23,8 @@ import javax.websocket.server.ServerEndpoint;
 @ServerEndpoint("/")
 public class CodeWsEndpoint {
     private Session session;
+    private boolean compiling;
+    private double progress;
 
     @OnOpen
     public void open(Session session) {
@@ -32,13 +34,27 @@ public class CodeWsEndpoint {
         if (consumer != null) {
             consumer.accept(this);
         }
+        if (compiling) {
+            sendProgress(progress);
+        }
     }
 
     public void progress(double value) {
-        session.getAsyncRemote().sendText("{ \"command\": \"compiling\", \"progress\": " + value + " }");
+        if (session != null) {
+            sendProgress(value);
+        }
+        compiling = true;
+        progress = value;
     }
 
     public void complete(boolean success) {
-        session.getAsyncRemote().sendText("{ \"command\": \"complete\", \"success\": " + success + " }");
+        if (session != null) {
+            session.getAsyncRemote().sendText("{ \"command\": \"complete\", \"success\": " + success + " }");
+        }
+        compiling = false;
+    }
+
+    private void sendProgress(double value) {
+        session.getAsyncRemote().sendText("{ \"command\": \"compiling\", \"progress\": " + value + " }");
     }
 }
diff --git a/tools/devserver/src/main/java/org/teavm/devserver/DevServer.java b/tools/devserver/src/main/java/org/teavm/devserver/DevServer.java
index 507c00d1b..8aa43a639 100644
--- a/tools/devserver/src/main/java/org/teavm/devserver/DevServer.java
+++ b/tools/devserver/src/main/java/org/teavm/devserver/DevServer.java
@@ -37,10 +37,11 @@ import org.teavm.tooling.TeaVMToolLog;
 public class DevServer {
     private String mainClass;
     private String[] classPath;
-    private String pathToFile = "";
+    private String pathToFile = "/";
     private String fileName = "classes.js";
     private List<String> sourcePath = new ArrayList<>();
     private boolean indicator;
+    private boolean reloadedAutomatically;
     private TeaVMToolLog log = new ConsoleTeaVMToolLog(false);
 
     private Server server;
@@ -80,6 +81,10 @@ public class DevServer {
         this.indicator = indicator;
     }
 
+    public void setReloadedAutomatically(boolean reloadedAutomatically) {
+        this.reloadedAutomatically = reloadedAutomatically;
+    }
+
     public List<String> getSourcePath() {
         return sourcePath;
     }
@@ -99,6 +104,7 @@ public class DevServer {
         servlet.setLog(log);
         servlet.getSourcePath().addAll(sourcePath);
         servlet.setIndicator(indicator);
+        servlet.setAutomaticallyReloaded(reloadedAutomatically);
         servlet.setPort(port);
         context.addServlet(new ServletHolder(servlet), "/*");
 
diff --git a/tools/devserver/src/main/resources/org/teavm/devserver/indicator.js b/tools/devserver/src/main/resources/org/teavm/devserver/indicator.js
index 3e191a329..539041f3c 100644
--- a/tools/devserver/src/main/resources/org/teavm/devserver/indicator.js
+++ b/tools/devserver/src/main/resources/org/teavm/devserver/indicator.js
@@ -15,6 +15,7 @@
  */
 (function () {
     var boot = BOOT_FLAG;
+    var reload = RELOAD_FLAG;
 
     function createWebSocket() {
         var loc = window.location;
@@ -90,7 +91,7 @@
             timer: void 0,
 
             show: function(text, timeout) {
-                this.container.style.display = "";
+                this.container.style.display = "block";
                 this.label.innerText = text;
                 if (this.timer) {
                     clearTimeout(this.timer);
@@ -111,14 +112,27 @@
 
             hideProgress() {
                 this.progress.container.style.display = "none";
-            }
+            },
         };
     }
 
     var indicator = createIndicator();
-    window.addEventListener("load", function() {
+    function onLoad() {
         document.body.appendChild(indicator.container);
-    });
+    }
+
+    if (document.body) {
+        onLoad();
+    } else {
+        window.addEventListener("load", onLoad);
+    }
+
+    function startMain() {
+        ws.close();
+        window.removeEventListener("load", onLoad);
+        document.body.removeChild(indicator.container);
+        main();
+    }
 
     var ws = createWebSocket();
     ws.onmessage = function(event) {
@@ -131,12 +145,12 @@
             case "complete":
                 if (message.success) {
                     indicator.show("Compilation complete", 10);
-                    if (boot) {
+                    if (reload) {
+                        window.location.reload(true);
+                    } else if (boot) {
                         var scriptElem = document.createElement("script");
                         scriptElem.src = "FILE_NAME";
-                        scriptElem.onload = function() {
-                            main();
-                        };
+                        scriptElem.onload = startMain;
                         document.head.appendChild(scriptElem);
                     }
                 } else {