diff --git a/build/pkgs/gappy/dependencies b/build/pkgs/gappy/dependencies
index 616552288ea..a7aab9fb766 100644
--- a/build/pkgs/gappy/dependencies
+++ b/build/pkgs/gappy/dependencies
@@ -1,4 +1,4 @@
-$(PYTHON) cysignals gap | $(PYTHON_TOOLCHAIN)
+$(PYTHON) cysignals gap | $(PYTHON_TOOLCHAIN) sphinx
 
 ----------
 All lines of this file are ignored except the first.
diff --git a/build/pkgs/gappy/spkg-postinst.in b/build/pkgs/gappy/spkg-postinst.in
new file mode 100644
index 00000000000..e7fbb8aa82c
--- /dev/null
+++ b/build/pkgs/gappy/spkg-postinst.in
@@ -0,0 +1,18 @@
+if [ "$SAGE_SPKG_INSTALL_DOCS" = "yes" ]; then
+    cd src/docs/
+
+    # write conf.py override to give correct intersphinx mappings
+    mv conf.py orig_conf.py
+    cat >> conf.py <<_EOF_
+with open('orig_conf.py') as f:
+    exec(f.read())
+
+intersphinx_mapping.update({
+    'python': (intersphinx_mapping['python'][0],
+               '$SAGE_SRC/doc/common/python3.inv')
+})
+_EOF_
+
+    make html
+    sdh_install _build/html/* "$SAGE_SHARE/doc/gappy"
+fi
diff --git a/build/pkgs/gappy/spkg-postrm.in b/build/pkgs/gappy/spkg-postrm.in
new file mode 100644
index 00000000000..f2747ee3dd1
--- /dev/null
+++ b/build/pkgs/gappy/spkg-postrm.in
@@ -0,0 +1,3 @@
+if [ -d "$SAGE_SHARE/doc/gappy" ]; then
+    rm -rf "$SAGE_SHARE/doc/gappy"
+fi