diff --git a/lib/base-compiler.js b/lib/base-compiler.js
index 946c1108..28f18238 100644
--- a/lib/base-compiler.js
+++ b/lib/base-compiler.js
@@ -31,6 +31,7 @@ var child_process = require('child_process'),
     utils = require('./utils'),
     quote = require('shell-quote'),
     _ = require('underscore-node'),
+    treeKill = require('tree-kill'),
     logger = require('./logger').logger;
 
 function Compile(compiler, env) {
@@ -265,12 +266,17 @@ Compile.prototype.exec = function (command, args, options) {
         env: env,
         detached: process.platform == 'linux'
     });
+    var running = true;
+    function kill() {
+        if (running) treeKill(child.pid);
+    }
     var stderr = "";
     var stdout = "";
     var timeout;
     if (timeoutMs) timeout = setTimeout(function () {
+        logger.warn("Timeout for", command, args, "after", timeoutMs, "ms");
         okToCache = false;
-        child.kill();
+        kill();
         stderr += "\nKilled - processing time exceeded";
     }, timeoutMs);
     var truncated = false;
@@ -279,7 +285,7 @@ Compile.prototype.exec = function (command, args, options) {
         if (stdout.length > maxOutput) {
             stdout += "\n[Truncated]";
             truncated = true;
-            child.kill();
+            kill();
             return;
         }
         stdout += data;
@@ -289,7 +295,7 @@ Compile.prototype.exec = function (command, args, options) {
         if (stderr.length > maxOutput) {
             stderr += "\n[Truncated]";
             truncated = true;
-            child.kill();
+            kill();
             return;
         }
         stderr += data;
@@ -297,6 +303,7 @@ Compile.prototype.exec = function (command, args, options) {
     child.on('exit', function (code) {
         logger.debug({type: 'exited', code: code});
         if (timeout !== undefined) clearTimeout(timeout);
+        running = false;
     });
     return new Promise(function (resolve, reject) {
         child.on('error', function (e) {
diff --git a/package.json b/package.json
index 0a987e9d..738bf154 100644
--- a/package.json
+++ b/package.json
@@ -30,6 +30,7 @@
     "serve-favicon": "2.3.x",
     "serve-static": "1.10.x",
     "temp": "0.8.x",
+    "tree-kill": "1.1.x",
     "underscore-node": "*",
     "shell-quote": "1.6.x",
     "winston": "2.2.x"