diff --git a/fuzzers/wcet_qemu_sys/Cargo.toml b/fuzzers/wcet_qemu_sys/Cargo.toml
index 1fedc8942a..1f69ba6957 100644
--- a/fuzzers/wcet_qemu_sys/Cargo.toml
+++ b/fuzzers/wcet_qemu_sys/Cargo.toml
@@ -21,3 +21,4 @@ hashbrown =  { version = "0.11", features = ["serde", "ahash-compile-time-rng"],
 nix = "0.23.0"
 goblin = "0.4.2"
 either = "1.6.1"
+num-traits = "0.2"
diff --git a/fuzzers/wcet_qemu_sys/src/bin/fuzzer.rs b/fuzzers/wcet_qemu_sys/src/bin/fuzzer.rs
index af43c4bd3b..a5bf2c827c 100644
--- a/fuzzers/wcet_qemu_sys/src/bin/fuzzer.rs
+++ b/fuzzers/wcet_qemu_sys/src/bin/fuzzer.rs
@@ -1,5 +1,6 @@
 //! A singlethreaded QEMU fuzzer that can auto-restart.
 
+use wcet_qemu_sys::worst::QemuHashMapObserver;
 use hashbrown::HashMap;
 use clap::{App, Arg};
 use core::{cell::RefCell, time::Duration};
@@ -64,7 +65,7 @@ use libafl_qemu::{
     clock::ClockFeedback,
     clock::QemuClockIncreaseFeedback
 };
-use wcet_qemu_sys::worst::{SortedFeedback,HitFeedback,HitcountsMapObserver,HitImprovingFeedback,LenTimeMaximizerCorpusScheduler};
+use wcet_qemu_sys::worst::{SortedFeedback,HitFeedback,HitImprovingFeedback,LenTimeMaximizerCorpusScheduler};
 
 
 /// The fuzzer main
@@ -276,7 +277,7 @@ fn fuzz(
     let edges = unsafe { &mut edges::EDGES_MAP };
     let edges_counter = unsafe { &mut edges::MAX_EDGES_NUM };
     let edges_observer =
-        HitcountsMapObserver::new(VariableMapObserver::new("edges", edges, edges_counter));
+        QemuHashMapObserver::new(VariableMapObserver::new("edges", edges, edges_counter));
 
     // Create an observation channel to keep track of the execution time
     // let time_observer = TimeObserver::new("time");
@@ -301,14 +302,14 @@ fn fuzz(
     let feedback = feedback_or!(
         // New maximization map feedback linked to the edges observer and the feedback state
         MaxMapFeedback::new_tracking(&feedback_state, &edges_observer, true, false),
-        // HitImprovingFeedback::new(target_map.clone()),
+        HitImprovingFeedback::new(target_map.clone(), &edges_observer),
         QemuClockIncreaseFeedback::default(),
         ClockFeedback::new_with_observer(&clock_observer)
     );
 
     // A feedback to choose if an input is a solution or not
-    // let objective = HitFeedback::new(target_map,0.0);
-    let objective = SortedFeedback::new();
+    let objective = HitFeedback::new(target_map,0.0,&edges_observer);
+    // let objective = SortedFeedback::new();
 
     // create a State from scratch
     let mut state = state.unwrap_or_else(||{
diff --git a/fuzzers/wcet_qemu_sys/src/bin/showmap.rs b/fuzzers/wcet_qemu_sys/src/bin/showmap.rs
index 3c00a127c9..8030fa7731 100644
--- a/fuzzers/wcet_qemu_sys/src/bin/showmap.rs
+++ b/fuzzers/wcet_qemu_sys/src/bin/showmap.rs
@@ -1,7 +1,8 @@
 //! A singlethreaded QEMU fuzzer that can auto-restart.
 
+use wcet_qemu_sys::worst::QemuHashMapObserver;
 use wcet_qemu_sys::{
-    worst::{DumpMapFeedback,DummyFeedback,HitcountsMapObserver},
+    worst::{DumpMapFeedback,DummyFeedback},
     system_trace::QemuSystemStateHelper,
 };
 use clap::{App, Arg};
@@ -262,13 +263,13 @@ fn fuzz(
     let edges = unsafe { &mut edges::EDGES_MAP };
     let edges_counter = unsafe { &mut edges::MAX_EDGES_NUM };
     let edges_observer =
-        HitcountsMapObserver::new(VariableMapObserver::new("edges", edges, edges_counter));
+        QemuHashMapObserver::new(VariableMapObserver::new("edges", edges, edges_counter));
 
     //========== Observe Execution Cycles
     let clock_observer = QemuClockObserver::default();
 
     //========= Feedback-Function evaluate the Maps. Need to dump it for debugging and check if it reaches targets.
-    let feedback = DumpMapFeedback::with_dump(dump_edges);
+    let feedback = DumpMapFeedback::with_dump(dump_edges, &edges_observer);
 
     // A feedback to choose if an input is a solution or not
     let objective = DummyFeedback::new(false);
diff --git a/fuzzers/wcet_qemu_sys/src/worst.rs b/fuzzers/wcet_qemu_sys/src/worst.rs
index e7ef49345b..8d9eb3024f 100644
--- a/fuzzers/wcet_qemu_sys/src/worst.rs
+++ b/fuzzers/wcet_qemu_sys/src/worst.rs
@@ -1,3 +1,5 @@
+use num_traits::PrimInt;
+use core::fmt::Debug;
 use core::cmp::Ordering::{Greater,Less,Equal};
 use libafl::inputs::BytesInput;
 use libafl::inputs::HasTargetBytes;
@@ -8,7 +10,6 @@ use core::marker::PhantomData;
 use libafl::corpus::MinimizerCorpusScheduler;
 use std::path::PathBuf;
 use std::fs;
-use libafl::observers::VariableMapObserver;
 use hashbrown::{HashMap};
 use libafl::observers::ObserversTuple;
 use libafl::executors::ExitKind;
@@ -30,36 +31,23 @@ use libafl::{
     observers::Observer,
     Error,
 };
-
-/// Map observer with hitcounts postprocessing
+//===================================================================
+/// A wrapper around some other [`MapObserver`], using [`QemuEdgesMapMetadata`] to offer a convinient Hashmap.
 #[derive(Serialize, Deserialize, Clone, Debug)]
 #[serde(bound = "M: serde::de::DeserializeOwned")]
-pub struct HitcountsMapObserver<M>
+pub struct QemuHashMapObserver<M,T>
 where
     M: serde::Serialize + serde::de::DeserializeOwned,
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
 {
     base: M,
-    pub edgemap: HashMap<(u64,u64),u8>,
+    pub edgemap: HashMap<(u64,u64),T>,
 }
 
-static COUNT_CLASS_LOOKUP: [u8; 256] = [
-    0, 1, 2, 4, 8, 8, 8, 8, 16, 16, 16, 16, 16, 16, 16, 16, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32,
-    32, 32, 32, 32, 32, 32, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
-    64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
-    64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
-    64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64, 64,
-    64, 64, 64, 64, 64, 64, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128,
-    128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128,
-    128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128,
-    128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128,
-    128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128,
-    128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128,
-    128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128, 128,
-];
-
-impl<I, S, M> Observer<I, S> for HitcountsMapObserver<M>
+impl<I, S, M, T> Observer<I, S> for QemuHashMapObserver<M, T>
 where
-    M: MapObserver<u8> + Observer<I, S>,
+    M: MapObserver<T> + Observer<I, S>,
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
     S: HasMetadata,     // Need to grab the HashMap from a Helper
 {
     #[inline]
@@ -70,25 +58,18 @@ where
 
     #[inline]
     fn post_exec(&mut self, state: &mut S, input: &I) -> Result<(), Error> {
-        //new stuff
-        let original_hashmap=&state.metadata().get::<QemuEdgesMapMetadata>().unwrap().map;
+        let original_hashmap=&state.metadata().get::<QemuEdgesMapMetadata>().expect("QemuEdgesMapMetadata not found").map;
         for (key, val) in original_hashmap.iter() {
             self.edgemap.insert(*key,*self.base.get(*val as usize));
         }
-        // println!("Post-Exec Len: {} Cap: {}",self.edgemap.len(),self.edgemap.capacity());
-        // println!("{:#?}",self.edgemap);
-        //end new stuff
-        let cnt = self.usable_count();
-        for i in 0..cnt {
-            *self.get_mut(i) = COUNT_CLASS_LOOKUP[*self.get(i) as usize];
-        }
         self.base.post_exec(state, input)
     }
 }
 
-impl<M> Named for HitcountsMapObserver<M>
+impl<M, T> Named for QemuHashMapObserver<M, T>
 where
     M: Named + serde::Serialize + serde::de::DeserializeOwned,
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
 {
     #[inline]
     fn name(&self) -> &str {
@@ -96,9 +77,10 @@ where
     }
 }
 
-impl<M> HasLen for HitcountsMapObserver<M>
+impl<M, T> HasLen for QemuHashMapObserver<M, T>
 where
     M: MapObserver<u8>,
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
 {
     #[inline]
     fn len(&self) -> usize {
@@ -106,9 +88,10 @@ where
     }
 }
 
-impl<M> MapObserver<u8> for HitcountsMapObserver<M>
+impl<M, T> MapObserver<u8> for QemuHashMapObserver<M, T>
 where
     M: MapObserver<u8>,
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
 {
     #[inline]
     fn map(&self) -> Option<&[u8]> {
@@ -141,9 +124,10 @@ where
     }
 }
 
-impl<M> HitcountsMapObserver<M>
+impl<M, T> QemuHashMapObserver<M, T>
 where
     M: serde::Serialize + serde::de::DeserializeOwned,
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
 {
     /// Creates a new [`MapObserver`]
     pub fn new(base: M) -> Self {
@@ -156,15 +140,23 @@ where
 
 /// A [`HitFeedback`] reports as interesting when all predicted worst case edges have been matched.
 #[derive(Serialize, Deserialize, Clone, Debug)]
-pub struct HitFeedback {
-    target_map: HashMap<(u64,u64),u8>,
+#[serde(bound = "T: serde::de::DeserializeOwned")]
+pub struct HitFeedback<O, T>
+where
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
+    O: MapObserver<T>,
+{
+    target_map: HashMap<(u64,u64),T>,
     target_msd: f64,
+    phantom: PhantomData<(O, T)>,
 }
 
-impl<I, S> Feedback<I, S> for HitFeedback
+impl<I, S, T, O> Feedback<I, S> for HitFeedback<O, T>
 where
     I: Input,
     S: HasClientPerfMonitor,
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
+    O: MapObserver<T>,
 {
     fn is_interesting<EM, OT>(
         &mut self,
@@ -178,15 +170,17 @@ where
         EM: EventFirer<I>,
         OT: ObserversTuple<I, S>,
     {
-        let observer = _observers.match_name::<HitcountsMapObserver<VariableMapObserver<u8>>>("edges")
-            .expect("HitcountsMapObserver not found");
+        let observer = _observers.match_name::<QemuHashMapObserver<O, T>>("edges")
+            .expect("QemuHashMapObserver not found");
         if self.target_map.len() == 0 { return Ok(false) };
 
         let mut sum_of_square_difference : u64 = 0; // does not include found edges not in target
         for (edg, val) in &self.target_map {
             match observer.edgemap.get(&edg) {
-                Some(x) => sum_of_square_difference+=((cmp::max(*x,*val)-cmp::min(*x,*val)) as u64).pow(2),
-                None => sum_of_square_difference+=(*val as u64).pow(2),
+                Some(x) => {
+                    sum_of_square_difference+=((cmp::max(*x,*val)-cmp::min(*x,*val)).to_u64().unwrap()).pow(2);
+                },
+                None => sum_of_square_difference+=((*val).to_u64().unwrap()).pow(2),
             }
         }
         let mean_sum_of_squares = (sum_of_square_difference as f64) / (self.target_map.len() as f64);
@@ -200,99 +194,111 @@ where
     }
 }
 
-impl Named for HitFeedback {
+impl<O, T> Named for HitFeedback<O, T>
+where
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
+    O: MapObserver<T>,
+{
     #[inline]
     fn name(&self) -> &str {
         "HitFeedback"
     }
 }
 
-impl HitFeedback {
+impl<O, T> HitFeedback<O, T>
+where
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
+    O: MapObserver<T>,
+{
     /// Creates a new [`HitFeedback`]
     #[must_use]
-    pub fn new(target_map: HashMap<(u64,u64),u8>, target_msd: f64) -> Self {
-        Self {target_map: target_map, target_msd: target_msd}
-    }
-}
-
-impl Default for HitFeedback {
-    fn default() -> Self {
-        Self::new(HashMap::new(),0.0)
+    pub fn new(target_map: HashMap<(u64,u64),T>, target_msd: f64, _map_observer: &O) -> Self {
+        Self {target_map: target_map, target_msd: target_msd, phantom: PhantomData}
     }
 }
 
 //===================================================================
 
 
-/// A [`MapHitIncreaseFeedback`] reports as interesting when the total number of used edges increases.
-#[derive(Serialize, Deserialize, Clone, Debug)]
-pub struct MapHitIncreaseFeedback {
-    record_high : u64,
-}
+// /// A [`MapHitIncreaseFeedback`] reports as interesting when the total number of used edges increases.
+// #[derive(Serialize, Deserialize, Clone, Debug)]
+// pub struct MapHitIncreaseFeedback {
+//     record_high : u64,
+// }
 
-impl<I, S> Feedback<I, S> for MapHitIncreaseFeedback
-where
-    I: Input,
-    S: HasClientPerfMonitor,
-{
-    fn is_interesting<EM, OT>(
-        &mut self,
-        _state: &mut S,
-        _manager: &mut EM,
-        _input: &I,
-        _observers: &OT,
-        _exit_kind: &ExitKind,
-    ) -> Result<bool, Error>
-    where
-        EM: EventFirer<I>,
-        OT: ObserversTuple<I, S>,
-    {
-        let observer = _observers.match_name::<HitcountsMapObserver<VariableMapObserver<u8>>>("edges")
-            .expect("HitcountsMapObserver not found");
-        let cur = observer.edgemap.values().fold(0,|a,b| a+(*b as u64));
-        if cur > self.record_high {
-            self.record_high = cur;
-            return Ok(true);
-        }
-        return Ok(false);
-    }
-}
+// impl<I, S, O, T> Feedback<I, S> for MapHitIncreaseFeedback
+// where
+//     I: Input,
+//     S: HasClientPerfMonitor,
+//     T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
+//     O: MapObserver<T>,
+// {
+//     fn is_interesting<EM, OT>(
+//         &mut self,
+//         _state: &mut S,
+//         _manager: &mut EM,
+//         _input: &I,
+//         _observers: &OT,
+//         _exit_kind: &ExitKind,
+//     ) -> Result<bool, Error>
+//     where
+//         EM: EventFirer<I>,
+//         OT: ObserversTuple<I, S>,
+//     {
+//         let observer = _observers.match_name::<QemuHashMapObserver<O, T>>("edges")
+//             .expect("QemuHashMapObserver not found");
+//         let cur = observer.edgemap.values().fold(0,|a,b| a+(*b as u64));
+//         if cur > self.record_high {
+//             self.record_high = cur;
+//             return Ok(true);
+//         }
+//         return Ok(false);
+//     }
+// }
 
-impl Named for MapHitIncreaseFeedback {
-    #[inline]
-    fn name(&self) -> &str {
-        "HitFeedback"
-    }
-}
+// impl Named for MapHitIncreaseFeedback {
+//     #[inline]
+//     fn name(&self) -> &str {
+//         "HitFeedback"
+//     }
+// }
 
-impl MapHitIncreaseFeedback {
-    /// Creates a new [`HitFeedback`]
-    #[must_use]
-    pub fn new() -> Self {
-        Self {record_high: 0}
-    }
-}
+// impl MapHitIncreaseFeedback {
+//     /// Creates a new [`HitFeedback`]
+//     #[must_use]
+//     pub fn new() -> Self {
+//         Self {record_high: 0}
+//     }
+// }
 
-impl Default for MapHitIncreaseFeedback {
-    fn default() -> Self {
-        Self::new()
-    }
-}
+// impl Default for MapHitIncreaseFeedback {
+//     fn default() -> Self {
+//         Self::new()
+//     }
+// }
 
 //===================================================================
 
 
 /// A [`HitFeedback`] reports as interesting when all predicted worst case edges have been matched.
 #[derive(Serialize, Deserialize, Clone, Debug)]
-pub struct HitImprovingFeedback {
-    target_map: HashMap<(u64,u64),u8>,
+#[serde(bound = "T: serde::de::DeserializeOwned")]
+pub struct HitImprovingFeedback<O, T>
+where
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
+    O: MapObserver<T>,
+{
+    target_map: HashMap<(u64,u64),T>,
     best_msd: f64,
+    phantom: PhantomData<(O, T)>,
 }
 
-impl<I, S> Feedback<I, S> for HitImprovingFeedback
+impl<O, T, I, S> Feedback<I, S> for HitImprovingFeedback<O, T>
 where
     I: Input,
     S: HasClientPerfMonitor,
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
+    O: MapObserver<T>,
 {
     fn is_interesting<EM, OT>(
         &mut self,
@@ -306,15 +312,17 @@ where
         EM: EventFirer<I>,
         OT: ObserversTuple<I, S>,
     {
-        let observer = _observers.match_name::<HitcountsMapObserver<VariableMapObserver<u8>>>("edges")
-            .expect("HitcountsMapObserver not found");
+        let observer = _observers.match_name::<QemuHashMapObserver<O, T>>("edges")
+            .expect("QemuHashMapObserver not found");
         if self.target_map.len() == 0 { return Ok(false) };
 
         let mut sum_of_square_difference : u64 = 0; // does not include found edges not in target
         for (edg, val) in &self.target_map {
             match observer.edgemap.get(&edg) {
-                Some(x) => sum_of_square_difference+=((cmp::max(*x,*val)-cmp::min(*x,*val)) as u64).pow(2),
-                None => sum_of_square_difference+=(*val as u64).pow(2),
+                Some(x) => {
+                    sum_of_square_difference+=((cmp::max(*x,*val)-cmp::min(*x,*val)).to_u64().unwrap()).pow(2);
+                },
+                None => sum_of_square_difference+=((*val).to_u64().unwrap()).pow(2),
             }
         }
         let mean_sum_of_squares = (sum_of_square_difference as f64) / (self.target_map.len() as f64);
@@ -329,38 +337,47 @@ where
     }
 }
 
-impl Named for HitImprovingFeedback {
+impl<O, T> Named for HitImprovingFeedback<O, T>
+where
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
+    O: MapObserver<T>,
+{
     #[inline]
     fn name(&self) -> &str {
-        "HitFeedback"
+        "HitImprovingFeedback"
     }
 }
 
-impl HitImprovingFeedback {
-    /// Creates a new [`HitFeedback`]
+impl<O, T> HitImprovingFeedback<O, T>
+where
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
+    O: MapObserver<T>,
+{
+    /// Creates a new [`HitImprovingFeedback`]
     #[must_use]
-    pub fn new(target_map: HashMap<(u64,u64),u8>) -> Self {
-        Self {target_map: target_map, best_msd: f64::MAX}
-    }
-}
-
-impl Default for HitImprovingFeedback {
-    fn default() -> Self {
-        Self::new(HashMap::new())
+    pub fn new(target_map: HashMap<(u64,u64),T>, _map_observer: &O) -> Self {
+        Self {target_map: target_map, best_msd: f64::MAX, phantom: PhantomData}
     }
 }
 
 //=========================== Debugging Feedback
 /// A [`Feedback`] meant to dump the edgemap for debugging.
 #[derive(Debug)]
-pub struct DumpMapFeedback {
-    dumpfile: Option<PathBuf>
+pub struct DumpMapFeedback<O, T>
+where
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
+    O: MapObserver<T>,
+{
+    dumpfile: Option<PathBuf>,
+    phantom: PhantomData<(O, T)>,
 }
 
-impl<I, S> Feedback<I, S> for DumpMapFeedback
+impl<I, S, O, T> Feedback<I, S> for DumpMapFeedback<O, T>
 where
     I: Input,
     S: HasClientPerfMonitor,
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
+    O: MapObserver<T>,
 {
     fn is_interesting<EM, OT>(
         &mut self,
@@ -374,8 +391,8 @@ where
         EM: EventFirer<I>,
         OT: ObserversTuple<I, S>,
     {
-        let observer = _observers.match_name::<HitcountsMapObserver<VariableMapObserver<u8>>>("edges")
-            .expect("HitcountsMapObserver not found");
+        let observer = _observers.match_name::<QemuHashMapObserver<O, T>>("edges")
+            .expect("QemuHashMapObserver not found");
         match &self.dumpfile {
             Some(s) => {
                     fs::write(s,ron::to_string(&observer.edgemap).expect("Error serializing hashmap")).expect("Can not dump to file");
@@ -387,27 +404,29 @@ where
     }
 }
 
-impl Named for DumpMapFeedback {
+impl<O, T> Named for DumpMapFeedback<O, T>
+where
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
+    O: MapObserver<T>,
+{
     #[inline]
     fn name(&self) -> &str {
         "HitFeedback"
     }
 }
 
-impl DumpMapFeedback {
+impl<O, T> DumpMapFeedback<O, T>
+where
+    T: PrimInt + Default + Copy + 'static + Serialize + serde::de::DeserializeOwned + Debug,
+    O: MapObserver<T>,
+{
     /// Creates a new [`HitFeedback`]
     #[must_use]
-    pub fn new() -> Self {
-        Self {dumpfile: None}
+    pub fn new(_map_observer: &O) -> Self {
+        Self {dumpfile: None, phantom: PhantomData}
     }
-    pub fn with_dump(dumpfile: Option<PathBuf>) -> Self {
-        Self {dumpfile: dumpfile}
-    }
-}
-
-impl Default for DumpMapFeedback {
-    fn default() -> Self {
-        Self::new()
+    pub fn with_dump(dumpfile: Option<PathBuf>,_map_observer: &O) -> Self {
+        Self {dumpfile: dumpfile, phantom: PhantomData}
     }
 }
 
@@ -511,6 +530,8 @@ where
     }
 }
 
+//===================================================================
+
 /// A Feedback reporting if the Input consists of strictly decreasing bytes.
 #[derive(Serialize, Deserialize, Clone, Debug)]
 pub struct SortedFeedback {