diff --git a/CHANGELOG.md b/CHANGELOG.md
index 85fe04187..c9c1d2011 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -3,6 +3,7 @@
 ## [Unreleased]
 
 - Updated pip from 25.3 to 26.0.1. ([#2032](https://github.com/heroku/heroku-buildpack-python/pull/2032))
+- Explicitly configured uv to use hard links to maintain the behaviour of previous versions. ([#2044](https://github.com/heroku/heroku-buildpack-python/pull/2044))
 
 ## [v336] - 2026-03-02
 
diff --git a/lib/uv.sh b/lib/uv.sh
index 927c84821..53d66e990 100644
--- a/lib/uv.sh
+++ b/lib/uv.sh
@@ -88,6 +88,9 @@ function uv::install_uv() {
 	# Prevent uv from downloading/using its own Python installation.
 	export UV_NO_MANAGED_PYTHON="1"
 	export UV_PYTHON_DOWNLOADS="never"
+	# Force uv to use hardlinks rather than the new default of reflinks, since the latter are
+	# significantly slower on Kodon: https://github.com/astral-sh/uv/issues/18259
+	export UV_LINK_MODE="hardlink"
 
 	# Set the same env vars in the environment used by later buildpacks.
 	cat >>"${export_file}" <<-EOF
@@ -95,6 +98,7 @@ function uv::install_uv() {
 		export UV_PROJECT_ENVIRONMENT="${python_home}"
 		export UV_NO_MANAGED_PYTHON="1"
 		export UV_PYTHON_DOWNLOADS="never"
+		export UV_LINK_MODE="hardlink"
 	EOF
 
 	# As a performance optimisation, uv attempts to use hardlinks instead of copying files from its
diff --git a/spec/hatchet/ci_spec.rb b/spec/hatchet/ci_spec.rb
index 60319499b..9b4ba8af9 100644
--- a/spec/hatchet/ci_spec.rb
+++ b/spec/hatchet/ci_spec.rb
@@ -319,6 +319,7 @@
                  PATH=/tmp/cache\\w+/.heroku/python-uv:/app/.heroku/python/bin:/usr/local/bin:/usr/bin:/bin:/app/.sprettur/bin/
                  PKG_CONFIG_PATH=/app/.heroku/python/lib/pkg-config
                  PYTHONUNBUFFERED=1
+                 UV_LINK_MODE=hardlink
                  UV_NO_MANAGED_PYTHON=1
                  UV_PROJECT_ENVIRONMENT=/app/.heroku/python
                  UV_PYTHON_DOWNLOADS=never
@@ -331,6 +332,7 @@
           PYTHONHOME=/app/.heroku/python
           PYTHONPATH=/app
           PYTHONUNBUFFERED=true
+          UV_LINK_MODE=hardlink
           UV_NO_MANAGED_PYTHON=1
           UV_PROJECT_ENVIRONMENT=/app/.heroku/python
           UV_PYTHON_DOWNLOADS=never
diff --git a/spec/hatchet/uv_spec.rb b/spec/hatchet/uv_spec.rb
index 766df4dca..3b0d74c21 100644
--- a/spec/hatchet/uv_spec.rb
+++ b/spec/hatchet/uv_spec.rb
@@ -33,6 +33,7 @@
           remote:        PKG_CONFIG_PATH=/app/.heroku/python/lib/pkg-config
           remote:        PYTHONUNBUFFERED=1
           remote:        UV_CACHE_DIR=/tmp/uv-cache
+          remote:        UV_LINK_MODE=hardlink
           remote:        UV_NO_MANAGED_PYTHON=1
           remote:        UV_PROJECT_ENVIRONMENT=/app/.heroku/python
           remote:        UV_PYTHON_DOWNLOADS=never
@@ -46,6 +47,7 @@
           remote: PYTHONPATH=/app
           remote: PYTHONUNBUFFERED=true
           remote: UV_CACHE_DIR=/tmp/uv-cache
+          remote: UV_LINK_MODE=hardlink
           remote: UV_NO_MANAGED_PYTHON=1
           remote: UV_PROJECT_ENVIRONMENT=/app/.heroku/python
           remote: UV_PYTHON_DOWNLOADS=never