diff --git a/binding.js b/binding.js
index f600dec5..26cb8526 100644
--- a/binding.js
+++ b/binding.js
@@ -4,12 +4,12 @@ const fs = require('fs');
 const os = require('os');
 const path = require('path');
 
-const caw = require('caw');
 const simpleGet = require('simple-get');
 const semver = require('semver');
 const tar = require('tar');
 const detectLibc = require('detect-libc');
 
+const agent = require('./lib/agent');
 const platform = require('./lib/platform');
 
 // Use NPM-provided environment variable where available, falling back to require-based method for Electron
@@ -81,9 +81,7 @@ module.exports.download_vips = function () {
   const url = distBaseUrl + tarFilename;
   const simpleGetOpt = {
     url: url,
-    agent: caw(null, {
-      protocol: 'https'
-    })
+    agent: agent()
   };
   simpleGet(simpleGetOpt, function (err, response) {
     if (err) {
diff --git a/lib/agent.js b/lib/agent.js
new file mode 100644
index 00000000..cae55e1b
--- /dev/null
+++ b/lib/agent.js
@@ -0,0 +1,37 @@
+'use strict';
+
+const url = require('url');
+const tunnelAgent = require('tunnel-agent');
+
+const is = require('./is');
+
+const proxies = [
+  'HTTPS_PROXY',
+  'https_proxy',
+  'HTTP_PROXY',
+  'http_proxy',
+  'npm_config_https_proxy',
+  'npm_config_proxy'
+];
+
+function env (key) {
+  return process.env[key];
+}
+
+module.exports = function () {
+  try {
+    const proxy = url.parse(proxies.map(env).find(is.string));
+    const tunnel = proxy.protocol === 'https:'
+      ? tunnelAgent.httpsOverHttps
+      : tunnelAgent.httpsOverHttp;
+    return tunnel({
+      proxy: {
+        port: Number(proxy.port),
+        host: proxy.hostname,
+        proxyAuth: proxy.auth
+      }
+    });
+  } catch (err) {
+    return null;
+  }
+};
diff --git a/package.json b/package.json
index 1928b484..96bdb3de 100644
--- a/package.json
+++ b/package.json
@@ -69,13 +69,13 @@
     "vips"
   ],
   "dependencies": {
-    "caw": "^2.0.0",
     "color": "^2.0.0",
-    "detect-libc": "^0.2.0",
+    "detect-libc": "^1.0.2",
     "nan": "^2.7.0",
     "semver": "^5.4.1",
     "simple-get": "^2.7.0",
-    "tar": "^4.0.1"
+    "tar": "^4.0.1",
+    "tunnel-agent": "^0.6.0"
   },
   "devDependencies": {
     "async": "^2.5.0",
@@ -84,7 +84,7 @@
     "exif-reader": "^1.0.2",
     "icc": "^1.0.0",
     "mocha": "^4.0.1",
-    "nyc": "^11.1.0",
+    "nyc": "^11.3.0",
     "rimraf": "^2.6.1",
     "semistandard": "^11.0.0",
     "unzip": "^0.1.11"
diff --git a/test/unit/agent.js b/test/unit/agent.js
new file mode 100644
index 00000000..a49e0ed6
--- /dev/null
+++ b/test/unit/agent.js
@@ -0,0 +1,32 @@
+'use strict';
+
+const assert = require('assert');
+const agent = require('../../lib/agent');
+
+describe('HTTP agent', function () {
+  it('Without proxy', function () {
+    assert.strictEqual(null, agent());
+  });
+
+  it('HTTPS proxy with auth from HTTPS_PROXY', function () {
+    process.env.HTTPS_PROXY = 'https://user:pass@secure:123';
+    const proxy = agent();
+    delete process.env.HTTPS_PROXY;
+    assert.strictEqual('object', typeof proxy);
+    assert.strictEqual('secure', proxy.options.proxy.host);
+    assert.strictEqual(123, proxy.options.proxy.port);
+    assert.strictEqual('user:pass', proxy.options.proxy.proxyAuth);
+    assert.strictEqual(443, proxy.defaultPort);
+  });
+
+  it('HTTP proxy without auth from npm_config_proxy', function () {
+    process.env.npm_config_proxy = 'http://plaintext:456';
+    const proxy = agent();
+    delete process.env.npm_config_proxy;
+    assert.strictEqual('object', typeof proxy);
+    assert.strictEqual('plaintext', proxy.options.proxy.host);
+    assert.strictEqual(456, proxy.options.proxy.port);
+    assert.strictEqual(null, proxy.options.proxy.proxyAuth);
+    assert.strictEqual(443, proxy.defaultPort);
+  });
+});