diff --git a/lib/travis/api/app/endpoint/env_vars.rb b/lib/travis/api/app/endpoint/env_vars.rb
new file mode 100644
index 00000000..0bed10fe
--- /dev/null
+++ b/lib/travis/api/app/endpoint/env_vars.rb
@@ -0,0 +1,31 @@
+require 'travis/api/app'
+require 'travis/api/app/endpoint/setting_endpoint'
+
+class Travis::Api::App
+  class Endpoint
+    class EnvVars < SettingsEndpoint
+      define_method(:name) { :env_vars }
+      define_routes!
+
+      def update
+        data = JSON.parse(request.body.read)[singular_name]
+        previously_public = record.public?
+        record.update(data)
+
+        # if we update from private to public reset value
+        if !previously_public && record.public?
+          record.value = nil
+        end
+
+        if record.valid?
+          repo_settings.save
+          respond_with(record, type: singular_name, version: :v2)
+        else
+          status 422
+          respond_with(record, type: :validation_error, version: :v2)
+        end
+      end
+
+    end
+  end
+end
diff --git a/lib/travis/api/app/endpoint/setting_endpoint.rb b/lib/travis/api/app/endpoint/setting_endpoint.rb
index dc1fb13a..44aca127 100644
--- a/lib/travis/api/app/endpoint/setting_endpoint.rb
+++ b/lib/travis/api/app/endpoint/setting_endpoint.rb
@@ -21,13 +21,17 @@ class Travis::Api::App
       def create_settings_class(name)
         klass = Class.new(self) do
           define_method(:name) { name }
-          get("/", scope: :private) do index end
-          get("/:id", scope: :private) do show end
-          post("/", scope: :private) do create end
-          patch("/:id", scope: :private) do update end
-          delete("/:id", scope: :private) do destroy end
+          define_routes!
         end
       end
+
+      def define_routes!
+        get("/", scope: :private) do index end
+        get("/:id", scope: :private) do show end
+        post("/", scope: :private) do create end
+        patch("/:id", scope: :private) do update end
+        delete("/:id", scope: :private) do destroy end
+      end
     end
 
     # Rails style methods for easy overriding
diff --git a/spec/integration/v2/settings/env_vars_spec.rb b/spec/integration/v2/settings/env_vars_spec.rb
index 90a7d460..5c486f02 100644
--- a/spec/integration/v2/settings/env_vars_spec.rb
+++ b/spec/integration/v2/settings/env_vars_spec.rb
@@ -83,6 +83,20 @@ describe Travis::Api::App::SettingsEndpoint do
     end
 
     describe 'PATCH /settings/env_vars/:id' do
+      it 'resets value if private key is made public' do
+        settings = repo.settings
+        env_var = settings.env_vars.create(name: 'FOO', value: 'bar')
+        settings.save
+
+        body = { env_var: { public: true } }.to_json
+        response = patch "/settings/env_vars/#{env_var.id}?repository_id=#{repo.id}", body, headers
+        json = JSON.parse(response.body)
+        json['env_var']['value'].should be_nil
+
+        updated_env_var = repo.reload.settings.env_vars.find(env_var.id)
+        updated_env_var.value.decrypt.should be_nil
+      end
+
       it 'should update a key' do
         settings = repo.settings
         env_var = settings.env_vars.create(name: 'FOO', value: 'bar')