diff --git a/src/libstore/ca-specific-schema.sql b/src/libstore/ca-specific-schema.sql
index c01dc5a76..4ca91f585 100644
--- a/src/libstore/ca-specific-schema.sql
+++ b/src/libstore/ca-specific-schema.sql
@@ -32,6 +32,8 @@ create table if not exists RealisationsRefs (
     foreign key (referrer) references Realisations(id) on delete cascade,
     foreign key (realisationReference) references Realisations(id) on delete restrict
 );
+-- used by deletion trigger
+create index if not exists IndexRealisationsRefsRealisationReference on RealisationsRefs(realisationReference);
 
 -- used by QueryRealisationReferences
 create index if not exists IndexRealisationsRefs on RealisationsRefs(referrer);
diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc
index 76524b01c..5cc5c91cc 100644
--- a/src/libstore/local-store.cc
+++ b/src/libstore/local-store.cc
@@ -152,6 +152,8 @@ void migrateCASchema(SQLite& db, Path schemaPath, AutoCloseFD& lockFd)
                     select id from Realisations where outputPath = old.id
                     );
                 end;
+                -- used by deletion trigger
+                create index if not exists IndexRealisationsRefsRealisationReference on RealisationsRefs(realisationReference);
             )");
             txn.commit();
         }
diff --git a/tests/build-remote-content-addressed-floating.sh b/tests/build-remote-content-addressed-floating.sh
index 1f474dde0..e83b42b41 100644
--- a/tests/build-remote-content-addressed-floating.sh
+++ b/tests/build-remote-content-addressed-floating.sh
@@ -2,7 +2,7 @@ source common.sh
 
 file=build-hook-ca-floating.nix
 
-enableFeatures "ca-derivations ca-references"
+enableFeatures "ca-derivations"
 
 CONTENT_ADDRESSED=true
 
diff --git a/tests/ca/common.sh b/tests/ca/common.sh
index b9d415863..b104b5a78 100644
--- a/tests/ca/common.sh
+++ b/tests/ca/common.sh
@@ -1,5 +1,5 @@
 source ../common.sh
 
-enableFeatures "ca-derivations ca-references"
+enableFeatures "ca-derivations"
 
 restartDaemon
diff --git a/tests/ca/selfref-gc.sh b/tests/ca/selfref-gc.sh
index 89657f6de..248778894 100755
--- a/tests/ca/selfref-gc.sh
+++ b/tests/ca/selfref-gc.sh
@@ -4,7 +4,7 @@ source common.sh
 
 requireDaemonNewerThan "2.4pre20210626"
 
-sed -i 's/experimental-features .*/& ca-derivations ca-references nix-command flakes/' "$NIX_CONF_DIR"/nix.conf
+enableFeatures "ca-derivations nix-command flakes"
 
 export NIX_TESTS_CA_BY_DEFAULT=1
 cd ..
diff --git a/tests/nix-profile.sh b/tests/nix-profile.sh
index a7a4d4fa2..fad62b993 100644
--- a/tests/nix-profile.sh
+++ b/tests/nix-profile.sh
@@ -3,7 +3,7 @@ source common.sh
 clearStore
 clearProfiles
 
-enableFeatures "ca-derivations ca-references"
+enableFeatures "ca-derivations"
 restartDaemon
 
 # Make a flake.