diff --git a/src/server/server.ts b/src/server/server.ts
index 8acc42c76cb..22112c4cb7d 100644
--- a/src/server/server.ts
+++ b/src/server/server.ts
@@ -510,6 +510,13 @@ namespace ts.server {
     class IOSession extends Session {
         constructor(options: IoSessionOptions) {
             const { host, eventPort, globalTypingsCacheLocation, typingSafeListLocation, typesMapLocation, npmLocation, canUseEvents } = options;
+            
+            let event: Event;
+            if (canUseEvents && eventPort) {
+                const eventSender = new SocketEventSender(host, logger, eventPort);
+                event = eventSender.event;
+            }
+            
             const typingsInstaller = disableAutomaticTypingAcquisition
                 ? undefined
                 : new NodeTypingsInstaller(telemetryEnabled, logger, host, globalTypingsCacheLocation, typingSafeListLocation, typesMapLocation, npmLocation);
@@ -525,6 +532,7 @@ namespace ts.server {
                 logger,
                 canUseEvents,
                 eventPort,
+                event,
                 globalPlugins: options.globalPlugins,
                 pluginProbeLocations: options.pluginProbeLocations,
                 allowLocalPluginLoads: options.allowLocalPluginLoads });
diff --git a/src/server/session.ts b/src/server/session.ts
index 13f65a8cb4e..8ad9f7b245b 100644
--- a/src/server/session.ts
+++ b/src/server/session.ts
@@ -255,7 +255,8 @@ namespace ts.server {
         event: Event;
     }
 
-    class SocketEventSender implements EventSender {
+    /** @internal */
+    export class SocketEventSender implements EventSender {
         private host: ServerHost;
         private logger: Logger;
         private eventPort: number;
@@ -316,6 +317,11 @@ namespace ts.server {
          * Otherwise, events are sent through the host.
          */
         eventPort?: number;
+        /**
+         * An optional callback overriding the default behavior for sending events.
+         * if set, `canUseEvents` and `eventPort` are ignored.
+         */
+        event?: Event;
         eventHandler?: ProjectServiceEventHandler;
         throttleWaitMilliseconds?: number;
 
@@ -353,11 +359,14 @@ namespace ts.server {
             this.hrtime = opts.hrtime;
             this.logger = opts.logger;
             this.eventPort = opts.eventPort;
-            this.canUseEvents = opts.canUseEvents;
+            this.canUseEvents = opts.canUseEvents || !!opts.event;
 
             const { throttleWaitMilliseconds } = opts;
-            
-            if (this.eventPort && this.canUseEvents) {
+
+            if (opts.event) {
+                this.event = opts.event;
+            }
+            else if (this.eventPort && this.canUseEvents) {
                 const eventSender = new SocketEventSender(this.host, this.logger, this.eventPort);
                 this.event = eventSender.event;
             }