diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 5a0c0fdf0..2823684e6 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -1,6 +1,8 @@
 # Contributing to Nakadi
 
-**Thank you for your interest in Nakadi. Your contributions are highly welcome.**
+Nakadi is no longer developed in the open — please use Zalando's internal repository for contributing.
+
+## Archived
 
 There are multiple ways of getting involved:
 
diff --git a/README.md b/README.md
index d8353cc74..662f7d2a1 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,10 @@
 ## [Nakadi Event Broker](https://zalando.github.io/nakadi/)
 
+**Nakadi is no longer developed in the open as we've not seen usage outside of Zalando for many years. **
+If you are a Zalando employee, please use Zalando's internal repository for contributing.
+
+## ARCHIVED
+
 [![Build Status](https://travis-ci.org/zalando/nakadi.svg?branch=master)](https://travis-ci.org/zalando/nakadi)
 [![Codacy Badge](https://api.codacy.com/project/badge/Grade/785ccd4ab5e34867b760a8b07c3b62f1)](https://www.codacy.com/app/aruha/nakadi?utm_source=www.github.com&utm_medium=referral&utm_content=zalando/nakadi&utm_campaign=Badge_Grade)