3 files changed, 17 insertions, 17 deletions
diff --git a/dev/ci/ci-basic-overlay.sh b/dev/ci/ci-basic-overlay.sh
index de6dc9935b..b65430aa51 100755
--- a/dev/ci/ci-basic-overlay.sh
+++ b/dev/ci/ci-basic-overlay.sh
@@ -8,7 +8,7 @@ declare -a projects # the list of project repos that can be be overlayed
 # checks if the given argument is a known project
 function is_in_projects {
     local rc=1
-    for x in ${!projects[@]}; do
+    for x in ${projects[@]}; do
       if [ "$1" = "$x" ]; then rc=0; fi;
     done
     return rc
diff --git a/dev/ci/user-overlays/README.md b/dev/ci/user-overlays/README.md
index 14ee5e4199..cf1d71c1cd 100644
--- a/dev/ci/user-overlays/README.md
+++ b/dev/ci/user-overlays/README.md
@@ -5,27 +5,29 @@ have prepared a branch with the fix, you can add an "overlay" to your pull
 request to test it with the adapted version of the external project.
 
 An overlay is a file which defines where to look for the patched
-version so that testing is possible. This is done by calling the
-`overlay` command for each project with the project name (as used in
-the variables in [`ci-basic-overlay.sh`](../ci-basic-overlay.sh)), the
-location of your fork and the branch containing the patch on your
-fork.
-
-Moreover, the file contains very simple logic to test the pull request number
-or branch name and apply it only in this case.
-
+version so that testing is possible.
 The name of your overlay file should start with a five-digit pull request
 number, followed by a dash, anything (for instance your GitHub nickname
 and the branch name), then a `.sh` extension (`[0-9]{5}-[a-zA-Z0-9-_]+.sh`).
 
-Example: `13128-SkySkimmer-noinstance.sh` containing
+This file must contain one or more invocation of the `overlay` function:
+```
+overlay <project> <giturl> <ref> <prnumber> [<prbranch>]
+```
+Each call creates an overlay for `project` using a given `giturl` and
+`ref` which is active for `prnumber` or `prbranch` (`prbranch` defaults
+to `ref`).
 
+Example of an overlay for the project `elpi` that uses the branch `noinstance`
+from the fork of `SkySkimmer` and is active for pull request `13128`
 ```
 overlay elpi https://github.com/SkySkimmer/coq-elpi noinstance 13128
 ```
 
-See [`ci-common.sh`](../ci-common.sh) for the detailed documentation of
-the `overlay` function.
+Such a file can be created automatically using the scripts
+[`create_overlays.sh`](../../dev/tools/create_overlays.sh).
+See also the list of projects for which one can write an overlay in
+the file [`ci-basic-overlay.sh`](../ci-basic-overlay.sh).
 
 ### Branching conventions
 
diff --git a/dev/tools/pin-ci.sh b/dev/tools/pin-ci.sh
index dbf54d7f0a..676688bedc 100755
--- a/dev/tools/pin-ci.sh
+++ b/dev/tools/pin-ci.sh
@@ -38,9 +38,7 @@ process_development() {
 # Execute the script to set the overlay variables
 . $OVERLAYS
 
-# Find all variables declared in the base overlay of the form *_CI_GITURL
-for REPO_VAR in $(compgen -A variable | grep _CI_GITURL)
+for project in ${projects[@]}
 do
-  DEV=${REPO_VAR%_CI_GITURL}
-  process_development $DEV
+  process_development $project
 done