diff --git a/CONTRIBUTING.rst b/CONTRIBUTING.rst
index 4351dfcda..776e3c460 100644
--- a/CONTRIBUTING.rst
+++ b/CONTRIBUTING.rst
@@ -1,6 +1,13 @@
 Contributing to httpstan
 ========================
 
+Principles
+----------
+
+httpstan emerged out of a rewrite of an existing piece of software (PyStan)
+which was very difficult to maintain. httpstan aims to be maintainable. Code
+contributions should be readable and easy to understand.
+
 How to Make a Code Contribution
 -------------------------------
 
@@ -20,4 +27,5 @@ Coding Style
 httpstan code is `PEP 8`_ compliant. The project uses the code formatter black_ with a maximum
 line-length of 99 characters.
 
+.. _PEP 8: https://www.python.org/dev/peps/pep-0008/
 .. _black: https://pypi.org/project/black/
diff --git a/doc/source/developers.rst b/doc/source/developers.rst
index 8878b33bc..491ebaa65 100644
--- a/doc/source/developers.rst
+++ b/doc/source/developers.rst
@@ -3,5 +3,5 @@ Developer Resources
 
 Documents for httpstan developers are collected here:
 
-- `Release HOWTO <release-howto.rst>`
-- `Updating Stan Source <updating-stan-source.rst>`
+- :ref:`release-howto`
+- :ref:`updating-stan-source`
diff --git a/doc/source/release-howto.rst b/doc/source/release-howto.rst
index f88d9b081..95d2c52be 100644
--- a/doc/source/release-howto.rst
+++ b/doc/source/release-howto.rst
@@ -1,3 +1,7 @@
+:orphan:
+
+.. _release-howto:
+
 ===============
  Release HOWTO
 ===============
diff --git a/doc/source/updating-stan-source.rst b/doc/source/updating-stan-source.rst
index 5cafe07f9..734be7802 100644
--- a/doc/source/updating-stan-source.rst
+++ b/doc/source/updating-stan-source.rst
@@ -1,3 +1,7 @@
+:orphan:
+
+.. _updating-stan-source:
+
 ======================
  Updating Stan Source
 ======================