$ git diff master..foo -- index.js
diff --git a/index.js b/index.js
index 55de743..fc03968 100644
+var deprecate = require('depd')('helmet')
var DEFAULT_MIDDLEWARE = [
@@ -59,7 +61,6 @@ helmet.expectCt = require('expect-ct')
helmet.featurePolicy = require('feature-policy')
helmet.frameguard = require('frameguard')
helmet.hidePoweredBy = require('hide-powered-by')
-helmet.hpkp = require('hpkp')
helmet.hsts = require('hsts')
helmet.ieNoOpen = require('ienoopen')
helmet.noCache = require('nocache')
@@ -67,6 +68,9 @@ helmet.noSniff = require('dont-sniff-mimetype')
helmet.permittedCrossDomainPolicies = require('helmet-crossdomain')
helmet.referrerPolicy = require('referrer-policy')
helmet.xssFilter = require('x-xss-protection')
+helmet.hpkp = deprecate.function(require('hpkp'), 'helmet.hpkp is deprecated and will be removed in [email protected] You can use the `hpkp` module instead. For more, see https://github.com/helmetjs/helmet/issues/180.') middlewares = Object.keys(helmet)