diff --git a/test/k4FWCoreTest/src/components/ExampleFunctionalConsumer.cpp b/test/k4FWCoreTest/src/components/ExampleFunctionalConsumer.cpp
index 9bd3273d..c5150aa5 100644
--- a/test/k4FWCoreTest/src/components/ExampleFunctionalConsumer.cpp
+++ b/test/k4FWCoreTest/src/components/ExampleFunctionalConsumer.cpp
@@ -28,10 +28,8 @@
 #include <stdexcept>
 #include <string>
 
-// Which type of collection we are reading
-using colltype = edm4hep::MCParticleCollection;
-
-struct ExampleFunctionalConsumer final : Gaudi::Functional::Consumer<void(const colltype& input), BaseClass_t> {
+struct ExampleFunctionalConsumer final
+    : Gaudi::Functional::Consumer<void(const edm4hep::MCParticleCollection& input), BaseClass_t> {
   // The pair in KeyValue can be changed from python and it corresponds
   // to the name of the input collection
   ExampleFunctionalConsumer(const std::string& name, ISvcLocator* svcLoc)
@@ -40,7 +38,7 @@ struct ExampleFunctionalConsumer final : Gaudi::Functional::Consumer<void(const
   // This is the function that will be called to transform the data
   // Note that the function has to be const, as well as the collections
   // we get from the input
-  void operator()(const colltype& input) const override {
+  void operator()(const edm4hep::MCParticleCollection& input) const override {
     int i = 0;
     for (const auto& particle : input) {
       if ((particle.getPDG() != 1 + i + m_possibleOffset) ||
diff --git a/test/k4FWCoreTest/src/components/ExampleFunctionalProducer.cpp b/test/k4FWCoreTest/src/components/ExampleFunctionalProducer.cpp
index 295dead5..a5393e54 100644
--- a/test/k4FWCoreTest/src/components/ExampleFunctionalProducer.cpp
+++ b/test/k4FWCoreTest/src/components/ExampleFunctionalProducer.cpp
@@ -25,17 +25,14 @@
 
 #include <string>
 
-// Which collection we are producing
-using colltype = edm4hep::MCParticleCollection;
-
-struct ExampleFunctionalProducer final : Gaudi::Functional::Producer<colltype(), BaseClass_t> {
+struct ExampleFunctionalProducer final : Gaudi::Functional::Producer<edm4hep::MCParticleCollection(), BaseClass_t> {
   // The pair in KeyValue can be changed from python and it corresponds
   // to the name of the output collection
   ExampleFunctionalProducer(const std::string& name, ISvcLocator* svcLoc)
       : Producer(name, svcLoc, KeyValue("OutputCollection", "MCParticles")) {}
 
   // This is the function that will be called to produce the data
-  colltype operator()() const override {
+  edm4hep::MCParticleCollection operator()() const override {
     auto coll = edm4hep::MCParticleCollection();
     coll.push_back({1, 2, 3, 4, 5, 6, {}, {}, {}, {}, {}, {}});
     coll.push_back({2, 3, 4, 5, 6, 7, {}, {}, {}, {}, {}, {}});
diff --git a/test/k4FWCoreTest/src/components/ExampleFunctionalProducerMultiple.cpp b/test/k4FWCoreTest/src/components/ExampleFunctionalProducerMultiple.cpp
index a972f64c..2bae590e 100644
--- a/test/k4FWCoreTest/src/components/ExampleFunctionalProducerMultiple.cpp
+++ b/test/k4FWCoreTest/src/components/ExampleFunctionalProducerMultiple.cpp
@@ -30,14 +30,14 @@
 #include <string>
 
 // Which type of collections we are producing
-using Float_t         = podio::UserDataCollection<float>;
-using Particle_t      = edm4hep::MCParticleCollection;
-using SimTrackerHit_t = edm4hep::SimTrackerHitCollection;
-using TrackerHit_t    = edm4hep::TrackerHitCollection;
-using Track_t         = edm4hep::TrackCollection;
+using Float         = podio::UserDataCollection<float>;
+using Particle      = edm4hep::MCParticleCollection;
+using SimTrackerHit = edm4hep::SimTrackerHitCollection;
+using TrackerHit    = edm4hep::TrackerHitCollection;
+using Track         = edm4hep::TrackCollection;
 
 struct ExampleFunctionalProducerMultiple final
-    : Gaudi::Functional::Producer<std::tuple<Float_t, Particle_t, Particle_t, SimTrackerHit_t, TrackerHit_t, Track_t>(),
+    : Gaudi::Functional::Producer<std::tuple<Float, Particle, Particle, SimTrackerHit, TrackerHit, Track>(),
                                   BaseClass_t> {
   // The pairs in KeyValue can be changed from python and they correspond
   // to the names of the output collections
@@ -50,7 +50,7 @@ struct ExampleFunctionalProducerMultiple final
              KeyValue("OutputCollectionTrackerHits", "TrackerHits"), KeyValue("OutputCollectionTracks", "Tracks")}) {}
 
   // This is the function that will be called to produce the data
-  std::tuple<Float_t, Particle_t, Particle_t, SimTrackerHit_t, TrackerHit_t, Track_t> operator()() const override {
+  std::tuple<Float, Particle, Particle, SimTrackerHit, TrackerHit, Track> operator()() const override {
     // The following was copied and adapted from the
     // k4FWCoreTest_CreateExampleEventData test
 
@@ -92,7 +92,7 @@ struct ExampleFunctionalProducerMultiple final
     track.addToTrackerHits(trackerHit);
     track.addToTracks(track2);
 
-    return std::make_tuple(std::move(floatVector), std::move(particles), Particle_t(), std::move(simTrackerHits),
+    return std::make_tuple(std::move(floatVector), std::move(particles), Particle(), std::move(simTrackerHits),
                            std::move(trackerHits), std::move(tracks));
   }
 
diff --git a/test/k4FWCoreTest/src/components/ExampleFunctionalTransformerMultiple.cpp b/test/k4FWCoreTest/src/components/ExampleFunctionalTransformerMultiple.cpp
index 932b0e8b..83f64b97 100644
--- a/test/k4FWCoreTest/src/components/ExampleFunctionalTransformerMultiple.cpp
+++ b/test/k4FWCoreTest/src/components/ExampleFunctionalTransformerMultiple.cpp
@@ -39,13 +39,13 @@ using TrackerHitColl    = edm4hep::TrackerHitCollection;
 using TrackColl         = edm4hep::TrackCollection;
 
 // As a simple example, we'll write an integer and a collection of MCParticles
-using Counter_t  = podio::UserDataCollection<int>;
-using Particle_t = edm4hep::MCParticleCollection;
+using Counter  = podio::UserDataCollection<int>;
+using Particle = edm4hep::MCParticleCollection;
 
 struct ExampleFunctionalTransformerMultiple final
-    : Gaudi::Functional::MultiTransformer<std::tuple<Counter_t, Particle_t>(const FloatColl&, const ParticleColl&,
-                                                                            const SimTrackerHitColl&,
-                                                                            const TrackerHitColl&, const TrackColl&),
+    : Gaudi::Functional::MultiTransformer<std::tuple<Counter, Particle>(const FloatColl&, const ParticleColl&,
+                                                                        const SimTrackerHitColl&, const TrackerHitColl&,
+                                                                        const TrackColl&),
                                           BaseClass_t> {
   ExampleFunctionalTransformerMultiple(const std::string& name, ISvcLocator* svcLoc)
       : MultiTransformer(
@@ -59,11 +59,10 @@ struct ExampleFunctionalTransformerMultiple final
   // This is the function that will be called to transform the data
   // Note that the function has to be const, as well as the collections
   // we get from the input
-  std::tuple<Counter_t, Particle_t> operator()(const FloatColl& floatVector, const ParticleColl& particles,
-                                               const SimTrackerHitColl& simTrackerHits,
-                                               const TrackerHitColl&    trackerHits,
-                                               const TrackColl&         tracks) const override {
-    Counter_t counter;
+  std::tuple<Counter, Particle> operator()(const FloatColl& floatVector, const ParticleColl& particles,
+                                           const SimTrackerHitColl& simTrackerHits, const TrackerHitColl& trackerHits,
+                                           const TrackColl& tracks) const override {
+    Counter counter;
 
     counter.push_back(floatVector.size());