diff --git a/afl/src/engines/mod.rs b/afl/src/engines/mod.rs
index 6f536b636e..3685543e56 100644
--- a/afl/src/engines/mod.rs
+++ b/afl/src/engines/mod.rs
@@ -85,14 +85,15 @@ where
 
     /// Runs the input and triggers observers and feedback
     fn evaluate_input(&mut self, input: &I) -> Result<u32, AflError> {
-        self.reset_observers()?;
+        self.executor_mut().reset_observers()?;
         self.executor_mut().run_target(&input)?;
         self.set_executions(self.executions() + 1);
-        self.post_exec_observers()?;
+        self.executor_mut().post_exec_observers()?;
 
         let mut fitness = 0;
+        let observers = self.executor().observers();
         for feedback in self.feedbacks_mut() {
-            fitness += feedback.is_interesting(&input)?;
+            fitness += feedback.is_interesting(&input, observers)?;
         }
         Ok(fitness)
     }
@@ -225,14 +226,6 @@ where
         &mut self.metadatas
     }
 
-    fn observers(&self) -> &[Rc<RefCell<dyn Observer>>] {
-        &self.observers
-    }
-
-    fn observers_mut(&mut self) -> &mut Vec<Rc<RefCell<dyn Observer>>> {
-        &mut self.observers
-    }
-
     fn feedbacks(&self) -> &[Box<dyn Feedback<I>>] {
         &self.feedbacks
     }
diff --git a/afl/src/executors/inmemory.rs b/afl/src/executors/inmemory.rs
index 5963a52d14..f1903b2695 100644
--- a/afl/src/executors/inmemory.rs
+++ b/afl/src/executors/inmemory.rs
@@ -3,7 +3,7 @@ use core::ptr;
 
 use crate::executors::{Executor, ExitKind};
 use crate::inputs::Input;
-use crate::metamap::NamedAnyMap;
+use crate::serde_anymap::NamedSerdeAnyMap;
 use crate::observers::Observer;
 use crate::AflError;
 
@@ -14,7 +14,7 @@ where
     I: Input,
 {
     harness: HarnessFunction<I>,
-    observers: NamedAnyMap<dyn Observer>,
+    observers: NamedSerdeAnyMap<dyn Observer>,
 }
 
 static mut CURRENT_INMEMORY_EXECUTOR_PTR: *const c_void = ptr::null();
@@ -35,11 +35,11 @@ where
         Ok(ret)
     }
 
-    fn observers(&self) -> &NamedAnyMap<dyn Observer> {
+    fn observers(&self) -> &NamedSerdeAnyMap<dyn Observer> {
         &self.observers
     }
 
-    fn observers_mut(&mut self) -> &mut NamedAnyMap<dyn Observer> {
+    fn observers_mut(&mut self) -> &mut NamedSerdeAnyMap<dyn Observer> {
         &mut self.observers
     }
 }
@@ -55,7 +55,7 @@ where
         }
         Self {
             harness: harness_fn,
-            observers: NamedAnyMap::new(),
+            observers: NamedSerdeAnyMap::new(),
         }
     }
 }
diff --git a/afl/src/executors/mod.rs b/afl/src/executors/mod.rs
index e17d13b146..f71933454f 100644
--- a/afl/src/executors/mod.rs
+++ b/afl/src/executors/mod.rs
@@ -1,7 +1,7 @@
 pub mod inmemory;
 
 use crate::inputs::Input;
-use crate::metamap::NamedAnyMap;
+use crate::serde_anymap::NamedSerdeAnyMap;
 use crate::observers::Observer;
 use crate::AflError;
 
@@ -12,8 +12,6 @@ pub enum ExitKind {
     Timeout,
 }
 
-// TODO unbox input
-
 pub trait Executor<I>
 where
     I: Input,
@@ -22,33 +20,26 @@ where
     fn run_target(&mut self, input: &I) -> Result<ExitKind, AflError>;
 
     /// Get the linked observers
-    fn observers(&self) -> &NamedAnyMap<dyn Observer>;
+    fn observers(&self) -> &NamedSerdeAnyMap<dyn Observer>;
 
     /// Get the linked observers
-    fn observers_mut(&mut self) -> &mut NamedAnyMap<dyn Observer>;
+    fn observers_mut(&mut self) -> &mut NamedSerdeAnyMap<dyn Observer>;
 
     /// Add a linked observer
     fn add_observer(&mut self, observer: Box<dyn Observer>) {
-        self.observers_mut().insert(observer, observer.name());
+        let name = observer.name();
+        self.observers_mut().insert(observer, name);
     }
 
     /// Reset the state of all the observes linked to this executor
     fn reset_observers(&mut self) -> Result<(), AflError> {
-        for typeid in self.observers().all_typeids() {
-            for observer in self.observers_mut().all_by_typeid_mut(typeid).unwrap() {
-                observer.reset()?;
-            }
-        }
+        self.observers_mut().for_each_mut(|_, x| Ok(x.reset()?))?;
         Ok(())
     }
 
     /// Run the post exec hook for all the observes linked to this executor
     fn post_exec_observers(&mut self) -> Result<(), AflError> {
-        for typeid in self.observers().all_typeids() {
-            for observer in self.observers_mut().all_by_typeid_mut(typeid).unwrap() {
-                observer.post_exec()?;
-            }
-        }
+        self.observers_mut().for_each_mut(|_, x| Ok(x.post_exec()?))?;
         Ok(())
     }
 }
diff --git a/afl/src/feedbacks/mod.rs b/afl/src/feedbacks/mod.rs
index 7fe07f7efd..e22cc25144 100644
--- a/afl/src/feedbacks/mod.rs
+++ b/afl/src/feedbacks/mod.rs
@@ -1,16 +1,11 @@
-use alloc::rc::Rc;
 use alloc::vec::Vec;
-use core::any::Any;
-use core::cell::RefCell;
 use core::marker::PhantomData;
 use num::Integer;
-use serde::{Deserialize, Serialize};
 
 use crate::corpus::{Testcase, TestcaseMetadata};
-use crate::executors::Executor;
 use crate::inputs::Input;
-use crate::observers::MapObserver;
-use crate::serde_anymap::SerdeAny;
+use crate::observers::{Observer, MapObserver};
+use crate::serde_anymap::NamedSerdeAnyMap;
 use crate::AflError;
 
 pub trait Feedback<I>
@@ -18,7 +13,7 @@ where
     I: Input,
 {
     /// is_interesting should return the "Interestingness" from 0 to 255 (percent times 2.55)
-    fn is_interesting(&mut self, input: &I, executor: &dyn Executor<I>) -> Result<u32, AflError>;
+    fn is_interesting(&mut self, input: &I, observers: &NamedSerdeAnyMap<dyn Observer>) -> Result<u32, AflError>;
 
     /// Append to the testcase the generated metadata in case of a new corpus item
     fn append_metadata(&mut self, _testcase: &mut Testcase<I>) -> Result<(), AflError> {
@@ -100,21 +95,20 @@ impl<T, R, O, I> Feedback<I> for MapFeedback<T, R, O>
 where
     T: Integer + Copy + 'static,
     R: Reducer<T>,
-    O: MapObserver<T>,
+    O: MapObserver<T> + 'static,
     I: Input,
 {
-    fn is_interesting(&mut self, _input: &I, executor: &dyn Executor<I>) -> Result<u32, AflError> {
+    fn is_interesting(&mut self, _input: &I, observers: &NamedSerdeAnyMap<dyn Observer>) -> Result<u32, AflError> {
         let mut interesting = 0;
         // TODO optimize
-        let size = self.map_observer.borrow().map().len();
-        let mut history_map = self.history_map.borrow_mut();
-        let observer = self.map_observer.borrow();
+        let observer = observers.get::<O>(self.name).unwrap();
+        let size = observer.map().len();
         for i in 0..size {
-            let history = history_map[i];
+            let history = self.history_map[i];
             let item = observer.map()[i];
             let reduced = R::reduce(history, item);
             if history != reduced {
-                history_map[i] = reduced;
+                self.history_map[i] = reduced;
                 interesting += 1;
             }
         }
@@ -160,6 +154,7 @@ where
     }
 }
 
+/*
 #[derive(Serialize, Deserialize)]
 pub struct MapNoveltiesMetadata {
     novelties: Vec<usize>,
@@ -290,9 +285,10 @@ where
         }
     }
 }
+*/
 
 pub type MaxMapFeedback<T, O> = MapFeedback<T, MaxReducer<T>, O>;
 pub type MinMapFeedback<T, O> = MapFeedback<T, MinReducer<T>, O>;
 
-pub type MaxMapTrackerFeedback<T, O> = MapFeedback<T, MaxReducer<T>, O>;
-pub type MinMapTrackerFeedback<T, O> = MapFeedback<T, MinReducer<T>, O>;
+//pub type MaxMapTrackerFeedback<T, O> = MapFeedback<T, MaxReducer<T>, O>;
+//pub type MinMapTrackerFeedback<T, O> = MapFeedback<T, MinReducer<T>, O>;
diff --git a/afl/src/metamap.rs b/afl/src/metamap.rs
index 42d5dc23c1..dbc33500ae 100644
--- a/afl/src/metamap.rs
+++ b/afl/src/metamap.rs
@@ -291,7 +291,7 @@ where
     pub fn by_typeid_mut(&mut self, name: &'static str, typeid: &TypeId) -> Option<&mut B> {
         match self.map.get_mut(typeid) {
             None => None,
-            Some(h) => h.get(&name).map(|x| x.as_mut()),
+            Some(h) => h.get_mut(&name).map(|x| x.as_mut()),
         }
     }
 
diff --git a/afl/src/observers/mod.rs b/afl/src/observers/mod.rs
index 54ae4097e4..bc9d9ac8ef 100644
--- a/afl/src/observers/mod.rs
+++ b/afl/src/observers/mod.rs
@@ -3,13 +3,14 @@ extern crate num;
 use core::any::Any;
 use core::slice::from_raw_parts_mut;
 use num::Integer;
+use serde::{Deserialize, Serialize};
 
-use crate::metamap::AsAny;
+use crate::serde_anymap::{SerdeAny, SliceMut};
 use crate::AflError;
 
 /// Observers observe different information about the target.
 /// They can then be used by various sorts of feedback.
-pub trait Observer: Any + AsAny {
+pub trait Observer: SerdeAny + 'static {
     fn flush(&mut self) -> Result<(), AflError> {
         Ok(())
     }
@@ -35,7 +36,7 @@ where
     fn map_mut(&mut self) -> &mut [T];
 
     /// Get the initial value for reset()
-    fn initial(&self) -> &T;
+    fn initial(&self) -> T;
 
     /// Get the initial value for reset()
     fn initial_mut(&mut self) -> &mut T;
@@ -46,25 +47,27 @@ where
     /// Reset the map
     fn reset_map(&mut self) -> Result<(), AflError> {
         // Normal memset, see https://rust.godbolt.org/z/Trs5hv
+        let initial = self.initial();
         for i in self.map_mut().iter_mut() {
-            *i = T::zero();
+            *i = initial;
         }
         Ok(())
     }
 }
 
+#[derive(Serialize, Deserialize)]
 pub struct StdMapObserver<T>
 where
     T: Integer + Copy + 'static,
 {
-    map: &'static mut [T],
+    map: SliceMut<'static, T>,
     initial: T,
     name: &'static str,
 }
 
 impl<T> Observer for StdMapObserver<T>
 where
-    T: Integer + Copy,
+    T: Integer + Copy + 'static + serde::Serialize,
 {
     fn reset(&mut self) -> Result<(), AflError> {
         self.reset_map()
@@ -75,9 +78,9 @@ where
     }
 }
 
-impl<T> AsAny for StdMapObserver<T>
+impl<T> SerdeAny for StdMapObserver<T>
 where
-    T: Integer + Copy,
+    T: Integer + Copy + 'static + serde::Serialize,
 {
     fn as_any(&self) -> &dyn Any {
         self
@@ -92,15 +95,21 @@ where
     T: Integer + Copy,
 {
     fn map(&self) -> &[T] {
-        &self.map
+        match &self.map {
+            SliceMut::Ref(r) => r,
+            SliceMut::Owned(v) => v.as_slice()
+        }
     }
 
     fn map_mut(&mut self) -> &mut [T] {
-        &mut self.map
+        match &mut self.map {
+            SliceMut::Ref(r) => r,
+            SliceMut::Owned(v) => v.as_mut_slice()
+        }
     }
 
-    fn initial(&self) -> &T {
-        &self.initial
+    fn initial(&self) -> T {
+        self.initial
     }
 
     fn initial_mut(&mut self) -> &mut T {
@@ -120,7 +129,7 @@ where
     pub fn new(name: &'static str, map: &'static mut [T]) -> Self {
         let initial = if map.len() > 0 { map[0] } else { T::zero() };
         Self {
-            map: map,
+            map: SliceMut::Ref(map),
             initial: initial,
             name: name,
         }
@@ -131,7 +140,7 @@ where
         unsafe {
             let initial = if len > 0 { *map_ptr } else { T::zero() };
             StdMapObserver {
-                map: from_raw_parts_mut(map_ptr, len),
+                map: SliceMut::Ref(from_raw_parts_mut(map_ptr, len)),
                 initial: initial,
                 name: name,
             }
diff --git a/afl/src/serde_anymap.rs b/afl/src/serde_anymap.rs
index 72d8bf7fd6..7d625e2693 100644
--- a/afl/src/serde_anymap.rs
+++ b/afl/src/serde_anymap.rs
@@ -5,6 +5,10 @@ use alloc::boxed::Box;
 use core::any::{Any, TypeId};
 use core::default::Default;
 use core::fmt;
+use core::slice::{Iter, IterMut};
+use hashbrown::hash_map::{Keys, Values, ValuesMut};
+
+use crate::AflError;
 
 pub fn pack_type_id(id: u64) -> TypeId {
     unsafe { *(&id as *const u64 as *const TypeId) }
@@ -199,3 +203,241 @@ impl SerdeAnyMap {
         }
     }
 }
+
+#[derive(Serialize, Deserialize)]
+pub struct NamedSerdeAnyMap<B>
+where
+    B: ?Sized + SerdeAny,
+{
+    map: HashMap<u64, HashMap<u64, Box<B>>>,
+}
+
+impl<B> NamedSerdeAnyMap<B>
+where
+    B: ?Sized + SerdeAny,
+{
+    pub fn get<T>(&self, name: &'static str) -> Option<&T>
+    where
+        T: Any,
+    {
+        match self.map.get(&unpack_type_id(TypeId::of::<T>())) {
+            None => None,
+            Some(h) => h
+                .get(&xxhash_rust::xxh3::xxh3_64(name.as_bytes()))
+                .map(|x| x.as_any().downcast_ref::<T>().unwrap()),
+        }
+    }
+
+    pub fn by_typeid(&self, name: &'static str, typeid: &TypeId) -> Option<&B> {
+        match self.map.get(&unpack_type_id(*typeid)) {
+            None => None,
+            Some(h) => h.get(&xxhash_rust::xxh3::xxh3_64(name.as_bytes())).map(|x| x.as_ref()),
+        }
+    }
+
+    pub fn get_mut<T>(&mut self, name: &'static str) -> Option<&mut T>
+    where
+        T: Any,
+    {
+        match self.map.get_mut(&unpack_type_id(TypeId::of::<T>())) {
+            None => None,
+            Some(h) => h
+                .get_mut(&xxhash_rust::xxh3::xxh3_64(name.as_bytes()))
+                .map(|x| x.as_any_mut().downcast_mut::<T>().unwrap()),
+        }
+    }
+
+    pub fn by_typeid_mut(&mut self, name: &'static str, typeid: &TypeId) -> Option<&mut B> {
+        match self.map.get_mut(&unpack_type_id(*typeid)) {
+            None => None,
+            Some(h) => h.get_mut(&xxhash_rust::xxh3::xxh3_64(name.as_bytes())).map(|x| x.as_mut()),
+        }
+    }
+
+    pub fn get_all<T>(
+        &self,
+    ) -> Option<core::iter::Map<Values<'_, u64, Box<B>>, fn(&Box<B>) -> &T>>
+    where
+        T: Any,
+    {
+        match self.map.get(&unpack_type_id(TypeId::of::<T>())) {
+            None => None,
+            Some(h) => Some(h.values().map(|x| x.as_any().downcast_ref::<T>().unwrap())),
+        }
+    }
+
+    pub fn all_by_typeid(
+        &self,
+        typeid: &TypeId,
+    ) -> Option<core::iter::Map<Values<'_, u64, Box<B>>, fn(&Box<B>) -> &B>> {
+        match self.map.get(&unpack_type_id(*typeid)) {
+            None => None,
+            Some(h) => Some(h.values().map(|x| x.as_ref())),
+        }
+    }
+
+    pub fn get_all_mut<T>(
+        &mut self,
+    ) -> Option<core::iter::Map<ValuesMut<'_, u64, Box<B>>, fn(&mut Box<B>) -> &mut T>>
+    where
+        T: Any,
+    {
+        match self.map.get_mut(&unpack_type_id(TypeId::of::<T>())) {
+            None => None,
+            Some(h) => Some(
+                h.values_mut()
+                    .map(|x| x.as_any_mut().downcast_mut::<T>().unwrap()),
+            ),
+        }
+    }
+
+    pub fn all_by_typeid_mut(
+        &mut self,
+        typeid: &TypeId,
+    ) -> Option<core::iter::Map<ValuesMut<'_, u64, Box<B>>, fn(&mut Box<B>) -> &mut B>>
+    {
+        match self.map.get_mut(&unpack_type_id(*typeid)) {
+            None => None,
+            Some(h) => Some(h.values_mut().map(|x| x.as_mut())),
+        }
+    }
+
+    pub fn all_typeids(&self) -> core::iter::Map<Keys<'_, u64, HashMap<u64, Box<B>>>, fn(&u64) -> TypeId> {
+        self.map.keys().map(|x| pack_type_id(*x))
+    }
+
+    pub fn for_each(&self, func: fn(&TypeId, &Box<B>) -> Result<(), AflError>) -> Result<(), AflError> {
+        for (id, h) in self.map.iter() {
+            for x in h.values() {
+                func(&pack_type_id(*id), x)?;
+            }
+        }
+        Ok(())
+    }
+
+    pub fn for_each_mut(&mut self, func: fn(&TypeId, &mut Box<B>) -> Result<(), AflError>) -> Result<(), AflError> {
+        for (id, h) in self.map.iter_mut() {
+            for x in h.values_mut() {
+                func(&pack_type_id(*id), x)?;
+            }
+        }
+        Ok(())
+    }
+
+    pub fn insert(&mut self, val: Box<B>, name: &'static str) {
+        let id = unpack_type_id(val.type_id());
+        if !self.map.contains_key(&id) {
+            self.map.insert(id, HashMap::default());
+        }
+        self.map.get_mut(&id).unwrap().insert(xxhash_rust::xxh3::xxh3_64(name.as_bytes()), val);
+    }
+
+    pub fn len(&self) -> usize {
+        self.map.len()
+    }
+
+    pub fn contains_type<T>(&self) -> bool
+    where
+        T: Any,
+    {
+        self.map.contains_key(&unpack_type_id(TypeId::of::<T>()))
+    }
+
+    pub fn contains<T>(&self, name: &'static str) -> bool
+    where
+        T: Any,
+    {
+        match self.map.get(&unpack_type_id(TypeId::of::<T>())) {
+            None => false,
+            Some(h) => h.contains_key(&xxhash_rust::xxh3::xxh3_64(name.as_bytes())),
+        }
+    }
+
+    pub fn new() -> Self {
+        Self {
+            map: HashMap::default(),
+        }
+    }
+}
+
+impl<B> Default for NamedSerdeAnyMap<B>
+where
+    B: ?Sized + SerdeAny,
+{
+    fn default() -> Self {
+        Self::new()
+    }
+}
+
+#[derive(Serialize)]
+pub enum Ptr<'a, T: 'a + ?Sized> {
+    Ref(&'a T),
+    Owned(Box<T>),
+}
+
+impl<'de, 'a, T: 'a + ?Sized> Deserialize<'de> for Ptr<'a, T>
+where
+    Box<T>: Deserialize<'de>,
+{
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        Deserialize::deserialize(deserializer).map(Ptr::Owned)
+    }
+}
+
+#[derive(Serialize)]
+pub enum PtrMut<'a, T: 'a + ?Sized> {
+    Ref(&'a mut T),
+    Owned(Box<T>),
+}
+
+impl<'de, 'a, T: 'a + ?Sized> Deserialize<'de> for PtrMut<'a, T>
+where
+    Box<T>: Deserialize<'de>,
+{
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        Deserialize::deserialize(deserializer).map(PtrMut::Owned)
+    }
+}
+
+#[derive(Serialize)]
+pub enum Slice<'a, T: 'a + Sized> {
+    Ref(&'a [T]),
+    Owned(Vec<T>),
+}
+
+impl<'de, 'a, T: 'a + Sized> Deserialize<'de> for Slice<'a, T>
+where
+    Vec<T>: Deserialize<'de>,
+{
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        Deserialize::deserialize(deserializer).map(Slice::Owned)
+    }
+}
+
+#[derive(Serialize)]
+pub enum SliceMut<'a, T: 'a + Sized> {
+    Ref(&'a mut [T]),
+    Owned(Vec<T>),
+}
+
+impl<'de, 'a, T: 'a + Sized> Deserialize<'de> for SliceMut<'a, T>
+where
+    Vec<T>: Deserialize<'de>,
+{
+    fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
+    where
+        D: serde::Deserializer<'de>,
+    {
+        Deserialize::deserialize(deserializer).map(SliceMut::Owned)
+    }
+}
+