diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8cd6403..4f99374 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.1.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [3.1.1] - 2026-09-08
+
+### Added
+
+- **`CITATION.cff` and `.zenodo.json`.** GitHub shows a "Cite this repository" button, and every release from this one on is archived on Zenodo with its own DOI. The README has a Citation section with a BibTeX entry, and the release checklist in `docs/DEVELOPMENT.md` keeps the `CITATION.cff` version in step with `pyproject.toml`.
+
 ## [3.1.0] - 2026-09-08
 
 ### Added
diff --git a/CITATION.cff b/CITATION.cff
index 716e4fc..8475a76 100644
--- a/CITATION.cff
+++ b/CITATION.cff
@@ -7,7 +7,7 @@ authors:
   - family-names: Denyer
     given-names: Michael
     email: code.denyer@gmail.com
-version: 3.1.0
+version: 3.1.1
 date-released: 2026-09-08
 license: GPL-3.0-or-later
 repository-code: https://github.com/michael-denyer/pyLocusZoom
diff --git a/pyproject.toml b/pyproject.toml
index 142cbfa..a680bab 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "hatchling.build"
 
 [project]
 name = "pylocuszoom"
-version = "3.1.0"
+version = "3.1.1"
 description = "Publication-ready regional association plots with LD coloring, gene tracks, and recombination overlays"
 readme = "README.md"
 license = "GPL-3.0-or-later"
diff --git a/uv.lock b/uv.lock
index 8a917f3..5180a7a 100644
--- a/uv.lock
+++ b/uv.lock
@@ -1593,7 +1593,7 @@ wheels = [
 
 [[package]]
 name = "pylocuszoom"
-version = "3.1.0"
+version = "3.1.1"
 source = { editable = "." }
 dependencies = [
     { name = "adjusttext" },