diff --git a/afl/Cargo.toml b/afl/Cargo.toml
index 99c42680f7..d0b023a8e8 100644
--- a/afl/Cargo.toml
+++ b/afl/Cargo.toml
@@ -31,6 +31,7 @@ default = ["std"]
 std = []
 
 [dependencies]
+tuple_list = "0.1.2"
 hashbrown =  { version = "0.9", features = ["serde"] } # A faster hashmap, nostd compatible
 libc = "0.2" # For (*nix) libc
 num = "*"
diff --git a/afl/src/engines/mod.rs b/afl/src/engines/mod.rs
index f5a31360c3..d74811fe97 100644
--- a/afl/src/engines/mod.rs
+++ b/afl/src/engines/mod.rs
@@ -1,18 +1,18 @@
 //! The engine is the core piece of every good fuzzer
 
 use alloc::boxed::Box;
-use alloc::vec::Vec;
 use core::fmt::Debug;
 use core::marker::PhantomData;
 use hashbrown::HashMap;
 
 use crate::corpus::{Corpus, Testcase};
 use crate::events::{Event, EventManager};
-use crate::executors::Executor;
-use crate::feedbacks::Feedback;
+use crate::executors::{Executor, HasObservers};
+use crate::feedbacks::FeedbacksTuple;
 use crate::generators::Generator;
 use crate::inputs::Input;
-use crate::stages::Stage;
+use crate::observers::ObserversTuple;
+use crate::stages::StagesTuple;
 use crate::utils::{current_milliseconds, Rand};
 use crate::AflError;
 
@@ -22,10 +22,11 @@ pub trait StateMetadata: Debug {
 }
 
 /// The state a fuzz run.
-pub struct State<I, R>
+pub struct State<I, R, FT>
 where
     I: Input,
     R: Rand,
+    FT: FeedbacksTuple<I>,
 {
     /// How many times the executor ran the harness/target
     executions: usize,
@@ -34,14 +35,15 @@ where
     /// Metadata stored for this state by one of the components
     metadatas: HashMap<&'static str, Box<dyn StateMetadata>>,
     // additional_corpuses: HashMap<&'static str, Box<dyn Corpus>>,
-    feedbacks: Vec<Box<dyn Feedback<I>>>,
-    phantom: PhantomData<R>,
+    feedbacks: FT,
+    phantom: PhantomData<(I, R)>,
 }
 
-impl<I, R> State<I, R>
+impl<I, R, FT> State<I, R, FT>
 where
     I: Input,
     R: Rand,
+    FT: FeedbacksTuple<I>,
 {
     /// Get executions
     #[inline]
@@ -98,39 +100,31 @@ where
 
     /// Returns vector of feebacks
     #[inline]
-    pub fn feedbacks(&self) -> &[Box<dyn Feedback<I>>] {
+    pub fn feedbacks(&self) -> &FT {
         &self.feedbacks
     }
 
     /// Returns vector of feebacks (mutable)
     #[inline]
-    pub fn feedbacks_mut(&mut self) -> &mut Vec<Box<dyn Feedback<I>>> {
+    pub fn feedbacks_mut(&mut self) -> &mut FT {
         &mut self.feedbacks
     }
 
-    /// Adds a feedback
-    #[inline]
-    pub fn add_feedback(&mut self, feedback: Box<dyn Feedback<I>>) {
-        self.feedbacks_mut().push(feedback);
-    }
-
-    // TODO move some of these, like evaluate_input, to FuzzingEngine
+    // TODO move some of these, like evaluate_input, to Engine
 
     /// Runs the input and triggers observers and feedback
-    pub fn evaluate_input<E>(&mut self, input: &I, executor: &mut E) -> Result<u32, AflError>
+    pub fn evaluate_input<E, OT>(&mut self, input: &I, executor: &mut E) -> Result<u32, AflError>
     where
-        E: Executor<I>,
+        E: Executor<I> + HasObservers<OT>,
+        OT: ObserversTuple,
     {
         executor.reset_observers()?;
         executor.run_target(&input)?;
         self.set_executions(self.executions() + 1);
         executor.post_exec_observers()?;
 
-        let mut fitness = 0;
         let observers = executor.observers();
-        for feedback in self.feedbacks_mut() {
-            fitness += feedback.is_interesting(&input, observers)?;
-        }
+        let fitness = self.feedbacks_mut().is_interesting_all(&input, observers)?;
         Ok(fitness)
     }
 
@@ -138,10 +132,7 @@ where
     #[inline]
     pub fn discard_input(&mut self, input: &I) -> Result<(), AflError> {
         // TODO: This could probably be automatic in the feedback somehow?
-        for feedback in self.feedbacks_mut() {
-            feedback.discard_metadata(input)?;
-        }
-        Ok(())
+        self.feedbacks_mut().discard_metadata_all(&input)
     }
 
     /// Creates a new testcase, appending the metadata from each feedback
@@ -149,10 +140,7 @@ where
     pub fn input_to_testcase(&mut self, input: I, fitness: u32) -> Result<Testcase<I>, AflError> {
         let mut testcase = Testcase::new(input);
         testcase.set_fitness(fitness);
-        for feedback in self.feedbacks_mut() {
-            feedback.append_metadata(&mut testcase)?;
-        }
-
+        self.feedbacks_mut().append_metadata_all(&mut testcase)?;
         Ok(testcase)
     }
 
@@ -191,20 +179,21 @@ where
         }
     }
 
-    pub fn generate_initial_inputs<G, C, E, EM>(
+    pub fn generate_initial_inputs<G, C, E, OT, EM>(
         &mut self,
         rand: &mut R,
         corpus: &mut C,
         generator: &mut G,
-        engine: &mut Engine<E, I>,
+        engine: &mut Engine<E, OT, I>,
         manager: &mut EM,
         num: usize,
     ) -> Result<(), AflError>
     where
         G: Generator<I, R>,
         C: Corpus<I, R>,
-        E: Executor<I>,
-        EM: EventManager<C, E, I, R>,
+        E: Executor<I> + HasObservers<OT>,
+        OT: ObserversTuple,
+        EM: EventManager<C, E, OT, FT, I, R>,
     {
         let mut added = 0;
         for _ in 0..num {
@@ -226,29 +215,31 @@ where
         Ok(())
     }
 
-    pub fn new() -> Self {
+    pub fn new(feedbacks: FT) -> Self {
         Self {
             executions: 0,
             start_time: current_milliseconds(),
             metadatas: HashMap::default(),
-            feedbacks: vec![],
+            feedbacks: feedbacks,
             phantom: PhantomData,
         }
     }
 }
 
-pub struct Engine<E, I>
+pub struct Engine<E, OT, I>
 where
-    E: Executor<I>,
+    E: Executor<I> + HasObservers<OT>,
+    OT: ObserversTuple,
     I: Input,
 {
     executor: E,
-    phantom: PhantomData<I>,
+    phantom: PhantomData<(OT, I)>,
 }
 
-impl<E, I> Engine<E, I>
+impl<E, OT, I> Engine<E, OT, I>
 where
-    E: Executor<I>,
+    E: Executor<I> + HasObservers<OT>,
+    OT: ObserversTuple,
     I: Input,
 {
     /// Return the executor
@@ -271,35 +262,33 @@ where
     }
 }
 
-pub trait Fuzzer<EM, E, C, I, R>
+pub trait Fuzzer<ST, EM, E, OT, FT, C, I, R>
 where
-    EM: EventManager<C, E, I, R>,
-    E: Executor<I>,
+    ST: StagesTuple<EM, E, OT, FT, C, I, R>,
+    EM: EventManager<C, E, OT, FT, I, R>,
+    E: Executor<I> + HasObservers<OT>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
     C: Corpus<I, R>,
     I: Input,
     R: Rand,
 {
-    fn stages(&self) -> &[Box<dyn Stage<EM, E, C, I, R>>];
+    fn stages(&self) -> &ST;
 
-    fn stages_mut(&mut self) -> &mut Vec<Box<dyn Stage<EM, E, C, I, R>>>;
-
-    fn add_stage(&mut self, stage: Box<dyn Stage<EM, E, C, I, R>>) {
-        self.stages_mut().push(stage);
-    }
+    fn stages_mut(&mut self) -> &mut ST;
 
     fn fuzz_one(
         &mut self,
         rand: &mut R,
-        state: &mut State<I, R>,
+        state: &mut State<I, R, FT>,
         corpus: &mut C,
-        engine: &mut Engine<E, I>,
+        engine: &mut Engine<E, OT, I>,
         manager: &mut EM,
     ) -> Result<usize, AflError> {
         let (_, idx) = corpus.next(rand)?;
 
-        for stage in self.stages_mut() {
-            stage.perform(rand, state, corpus, engine, manager, idx)?;
-        }
+        self.stages_mut()
+            .perform_all(rand, state, corpus, engine, manager, idx)?;
 
         manager.process(state, corpus)?;
         Ok(idx)
@@ -308,9 +297,9 @@ where
     fn fuzz_loop(
         &mut self,
         rand: &mut R,
-        state: &mut State<I, R>,
+        state: &mut State<I, R, FT>,
         corpus: &mut C,
-        engine: &mut Engine<E, I>,
+        engine: &mut Engine<E, OT, I>,
         manager: &mut EM,
     ) -> Result<(), AflError> {
         let mut last = current_milliseconds();
@@ -328,44 +317,58 @@ where
     }
 }
 
-pub struct StdFuzzer<EM, E, C, I, R>
+pub struct StdFuzzer<ST, EM, E, OT, FT, C, I, R>
 where
-    EM: EventManager<C, E, I, R>,
-    E: Executor<I>,
+    ST: StagesTuple<EM, E, OT, FT, C, I, R>,
+    EM: EventManager<C, E, OT, FT, I, R>,
+    E: Executor<I> + HasObservers<OT>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
     C: Corpus<I, R>,
     I: Input,
     R: Rand,
 {
-    stages: Vec<Box<dyn Stage<EM, E, C, I, R>>>,
+    stages: ST,
+    phantom: PhantomData<(EM, E, OT, FT, C, I, R)>,
 }
 
-impl<EM, E, C, I, R> Fuzzer<EM, E, C, I, R> for StdFuzzer<EM, E, C, I, R>
+impl<ST, EM, E, OT, FT, C, I, R> Fuzzer<ST, EM, E, OT, FT, C, I, R>
+    for StdFuzzer<ST, EM, E, OT, FT, C, I, R>
 where
-    EM: EventManager<C, E, I, R>,
-    E: Executor<I>,
+    ST: StagesTuple<EM, E, OT, FT, C, I, R>,
+    EM: EventManager<C, E, OT, FT, I, R>,
+    E: Executor<I> + HasObservers<OT>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
     C: Corpus<I, R>,
     I: Input,
     R: Rand,
 {
-    fn stages(&self) -> &[Box<dyn Stage<EM, E, C, I, R>>] {
+    fn stages(&self) -> &ST {
         &self.stages
     }
 
-    fn stages_mut(&mut self) -> &mut Vec<Box<dyn Stage<EM, E, C, I, R>>> {
+    fn stages_mut(&mut self) -> &mut ST {
         &mut self.stages
     }
 }
 
-impl<EM, E, C, I, R> StdFuzzer<EM, E, C, I, R>
+impl<ST, EM, E, OT, FT, C, I, R> StdFuzzer<ST, EM, E, OT, FT, C, I, R>
 where
-    EM: EventManager<C, E, I, R>,
-    E: Executor<I>,
+    ST: StagesTuple<EM, E, OT, FT, C, I, R>,
+    EM: EventManager<C, E, OT, FT, I, R>,
+    E: Executor<I> + HasObservers<OT>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
     C: Corpus<I, R>,
     I: Input,
     R: Rand,
 {
-    pub fn new() -> Self {
-        Self { stages: vec![] }
+    pub fn new(stages: ST) -> Self {
+        Self {
+            stages: stages,
+            phantom: PhantomData,
+        }
     }
 }
 
@@ -374,8 +377,6 @@ where
 #[cfg(test)]
 mod tests {
 
-    use alloc::boxed::Box;
-
     #[cfg(feature = "std")]
     use std::io::stderr;
 
@@ -388,6 +389,7 @@ mod tests {
     use crate::inputs::bytes::BytesInput;
     use crate::mutators::{mutation_bitflip, ComposedByMutations, StdScheduledMutator};
     use crate::stages::mutational::StdMutationalStage;
+    use crate::tuples::tuple_list;
     use crate::utils::StdRand;
 
     fn harness<I>(_executor: &dyn Executor<I>, _buf: &[u8]) -> ExitKind {
@@ -402,18 +404,15 @@ mod tests {
         let testcase = Testcase::new(vec![0; 4]).into();
         corpus.add(testcase);
 
-        let executor = InMemoryExecutor::<BytesInput>::new(harness);
-        let mut state = State::new();
+        let executor = InMemoryExecutor::<BytesInput, _>::new(harness, tuple_list!());
+        let mut state = State::new(tuple_list!());
 
         let mut events_manager = LoggerEventManager::new(stderr());
         let mut engine = Engine::new(executor);
         let mut mutator = StdScheduledMutator::new();
         mutator.add_mutation(mutation_bitflip);
         let stage = StdMutationalStage::new(mutator);
-        let mut fuzzer = StdFuzzer::new();
-        fuzzer.add_stage(Box::new(stage));
-
-        //
+        let mut fuzzer = StdFuzzer::new(tuple_list!(stage));
 
         for i in 0..1000 {
             fuzzer
diff --git a/afl/src/events/mod.rs b/afl/src/events/mod.rs
index 3c1752023a..a65b6a5347 100644
--- a/afl/src/events/mod.rs
+++ b/afl/src/events/mod.rs
@@ -14,13 +14,15 @@ use serde::{Deserialize, Serialize};
 #[cfg(feature = "std")]
 use std::io::Write;
 
+use crate::corpus::Corpus;
 use crate::engines::State;
 use crate::executors::Executor;
+use crate::feedbacks::FeedbacksTuple;
 use crate::inputs::Input;
-use crate::serde_anymap::{Ptr, PtrMut};
+use crate::observers::ObserversTuple;
+use crate::serde_anymap::{Ptr, PtrMut, SerdeAny};
 use crate::utils::Rand;
 use crate::AflError;
-use crate::{corpus::Corpus, serde_anymap::SerdeAny};
 
 /// Indicate if an event worked or not
 pub enum BrokerEventResult {
@@ -33,7 +35,7 @@ pub enum BrokerEventResult {
 pub trait ShowStats {}
 
 /// A custom event, for own messages, with own handler.
-pub trait CustomEvent<I>: SerdeAny + Serialize
+pub trait CustomEvent<I, OT>: SerdeAny + Serialize
 where
     I: Input,
 {
@@ -48,9 +50,10 @@ where
 /// Events sent around in the library
 #[derive(Serialize, Deserialize)]
 #[serde(bound = "I: serde::de::DeserializeOwned")]
-pub enum Event<'a, I>
+pub enum Event<'a, I, OT>
 where
     I: Input,
+    OT: ObserversTuple,
 {
     LoadInitial {
         sender_id: u64,
@@ -59,7 +62,7 @@ where
     NewTestcase {
         sender_id: u64,
         input: Ptr<'a, I>,
-        observers: PtrMut<'a, crate::observers::observer_serde::NamedSerdeAnyMap>,
+        observers: PtrMut<'a, OT>,
         corpus_count: usize,
     },
     UpdateStats {
@@ -90,14 +93,14 @@ where
     Custom {
         sender_id: u64,
         // TODO: Allow custom events
-        // custom_event: Box<dyn CustomEvent<I>>,
+        // custom_event: Box<dyn CustomEvent<I, OT>>,
     },
 }
 
-impl<'a, I> Event<'a, I>
+impl<'a, I, OT> Event<'a, I, OT>
 where
     I: Input,
-    //CE: CustomEvent<I>,
+    OT: ObserversTuple, //CE: CustomEvent<I, OT>,
 {
     pub fn name(&self) -> &str {
         match self {
@@ -159,29 +162,31 @@ where
     }
 }
 
-pub trait EventManager<C, E, I, R>
+pub trait EventManager<C, E, OT, FT, I, R>
 where
     C: Corpus<I, R>,
     E: Executor<I>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
     I: Input,
     R: Rand,
 {
     /// Fire an Event
-    fn fire<'a>(&mut self, event: Event<'a, I>) -> Result<(), AflError>;
+    fn fire<'a>(&mut self, event: Event<'a, I, OT>) -> Result<(), AflError>;
 
     /// Lookup for incoming events and process them.
     /// Return the number of processes events or an error
-    fn process(&mut self, state: &mut State<I, R>, corpus: &mut C) -> Result<usize, AflError>;
+    fn process(&mut self, state: &mut State<I, R, FT>, corpus: &mut C) -> Result<usize, AflError>;
 
     #[inline]
-    fn on_recv(&self, _state: &mut State<I, R>, _corpus: &mut C) -> Result<(), AflError> {
+    fn on_recv(&self, _state: &mut State<I, R, FT>, _corpus: &mut C) -> Result<(), AflError> {
         // TODO: Better way to move out of testcase, or get ref
         //Ok(corpus.add(self.testcase.take().unwrap()))
         Ok(())
     }
 
     // TODO the broker has a state? do we need to pass state and corpus?
-    fn handle_in_broker(&mut self, event: &Event<I>) -> Result<BrokerEventResult, AflError> {
+    fn handle_in_broker(&mut self, event: &Event<I, OT>) -> Result<BrokerEventResult, AflError> {
         match event {
             Event::LoadInitial {
                 sender_id: _,
@@ -238,8 +243,8 @@ where
 
     fn handle_in_client(
         &mut self,
-        event: Event<I>,
-        _state: &mut State<I, R>,
+        event: Event<I, OT>,
+        _state: &mut State<I, R, FT>,
         _corpus: &mut C,
     ) -> Result<(), AflError> {
         match event {
@@ -263,7 +268,7 @@ where
 }
 
 /*TODO
-    fn on_recv(&self, state: &mut State<I, R>, _corpus: &mut C) -> Result<(), AflError> {
+    fn on_recv(&self, state: &mut State<I, R, FT>, _corpus: &mut C) -> Result<(), AflError> {
         println!(
             "#{}\t exec/s: {}",
             state.executions(),
@@ -275,10 +280,16 @@ where
 */
 
 #[cfg(feature = "std")]
-pub struct LoggerEventManager<C, E, I, R, W>
+pub struct LoggerEventManager<C, E, OT, FT, I, R, W>
 where
+    C: Corpus<I, R>,
+    E: Executor<I>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
+    I: Input,
+    R: Rand,
     W: Write,
-    //CE: CustomEvent<I>,
+    //CE: CustomEvent<I, OT>,
 {
     writer: W,
     count: usize,
@@ -288,21 +299,24 @@ where
     execs_over_sec: u64,
     corpus_count: usize,
 
-    phantom: PhantomData<(C, E, I, R)>,
+    phantom: PhantomData<(C, E, OT, FT, I, R)>,
 }
 
 #[cfg(feature = "std")]
-impl<C, E, I, R, W> EventManager<C, E, I, R> for LoggerEventManager<C, E, I, R, W>
+impl<C, E, OT, FT, I, R, W> EventManager<C, E, OT, FT, I, R>
+    for LoggerEventManager<C, E, OT, FT, I, R, W>
 where
     C: Corpus<I, R>,
     E: Executor<I>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
     I: Input,
     R: Rand,
     W: Write,
-    //CE: CustomEvent<I>,
+    //CE: CustomEvent<I, OT>,
 {
     #[inline]
-    fn fire<'a>(&mut self, event: Event<'a, I>) -> Result<(), AflError> {
+    fn fire<'a>(&mut self, event: Event<'a, I, OT>) -> Result<(), AflError> {
         match self.handle_in_broker(&event)? {
             BrokerEventResult::Forward => (), //self.handle_in_client(event, state, corpus)?,
             // Ignore broker-only events
@@ -311,13 +325,17 @@ where
         Ok(())
     }
 
-    fn process(&mut self, _state: &mut State<I, R>, _corpus: &mut C) -> Result<usize, AflError> {
+    fn process(
+        &mut self,
+        _state: &mut State<I, R, FT>,
+        _corpus: &mut C,
+    ) -> Result<usize, AflError> {
         let c = self.count;
         self.count = 0;
         Ok(c)
     }
 
-    fn handle_in_broker(&mut self, event: &Event<I>) -> Result<BrokerEventResult, AflError> {
+    fn handle_in_broker(&mut self, event: &Event<I, OT>) -> Result<BrokerEventResult, AflError> {
         match event {
             Event::NewTestcase {
                 sender_id: _,
@@ -377,11 +395,13 @@ where
 }
 
 #[cfg(feature = "std")]
-impl<C, E, I, R, W> LoggerEventManager<C, E, I, R, W>
+impl<C, E, OT, FT, I, R, W> LoggerEventManager<C, E, OT, FT, I, R, W>
 where
     C: Corpus<I, R>,
     I: Input,
     E: Executor<I>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
     R: Rand,
     W: Write,
     //TODO CE: CustomEvent,
@@ -400,16 +420,18 @@ where
 
 /// Eventmanager for multi-processed application
 #[cfg(feature = "std")]
-pub struct LlmpBrokerEventManager<C, E, I, R>
+pub struct LlmpBrokerEventManager<C, E, OT, FT, I, R>
 where
     C: Corpus<I, R>,
     I: Input,
     E: Executor<I>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
     R: Rand,
-    //CE: CustomEvent<I>,
+    //CE: CustomEvent<I, OT>,
 {
     llmp_broker: llmp::LlmpBroker,
-    phantom: PhantomData<(C, E, I, R)>,
+    phantom: PhantomData<(C, E, OT, FT, I, R)>,
 }
 
 #[cfg(feature = "std")]
@@ -424,35 +446,44 @@ const _LLMP_TAG_EVENT_TO_BOTH: llmp::Tag = 0x2B0741;
 
 /// Eventmanager for multi-processed application
 #[cfg(feature = "std")]
-pub struct LlmpClientEventManager<C, E, I, R>
+pub struct LlmpClientEventManager<C, E, OT, FT, I, R>
 where
     C: Corpus<I, R>,
     I: Input,
     E: Executor<I>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
     R: Rand,
-    //CE: CustomEvent<I>,
+    //CE: CustomEvent<I, OT>,
 {
     _llmp_client: llmp::LlmpClient,
-    phantom: PhantomData<(C, E, I, R)>,
+    phantom: PhantomData<(C, E, OT, FT, I, R)>,
 }
 
 #[cfg(feature = "std")]
-impl<C, E, I, R> EventManager<C, E, I, R> for LlmpBrokerEventManager<C, E, I, R>
+impl<C, E, OT, FT, I, R> EventManager<C, E, OT, FT, I, R>
+    for LlmpBrokerEventManager<C, E, OT, FT, I, R>
 where
     C: Corpus<I, R>,
     E: Executor<I>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
     I: Input,
     R: Rand,
 {
     /// Fire an Event
-    fn fire<'a>(&mut self, event: Event<'a, I>) -> Result<(), AflError> {
+    fn fire<'a>(&mut self, event: Event<'a, I, OT>) -> Result<(), AflError> {
         let serialized = postcard::to_allocvec(&event)?;
         self.llmp_broker
             .send_buf(LLMP_TAG_EVENT_TO_CLIENT, &serialized)?;
         Ok(())
     }
 
-    fn process(&mut self, _state: &mut State<I, R>, _corpus: &mut C) -> Result<usize, AflError> {
+    fn process(
+        &mut self,
+        _state: &mut State<I, R, FT>,
+        _corpus: &mut C,
+    ) -> Result<usize, AflError> {
         // TODO: iterators
         /*
         let mut handled = vec![];
@@ -481,13 +512,13 @@ where
         Ok(0)
     }
 
-    fn on_recv(&self, _state: &mut State<I, R>, _corpus: &mut C) -> Result<(), AflError> {
+    fn on_recv(&self, _state: &mut State<I, R, FT>, _corpus: &mut C) -> Result<(), AflError> {
         // TODO: Better way to move out of testcase, or get ref
         //Ok(corpus.add(self.testcase.take().unwrap()))
         Ok(())
     }
 
-    fn handle_in_broker(&mut self, event: &Event<I>) -> Result<BrokerEventResult, AflError> {
+    fn handle_in_broker(&mut self, event: &Event<I, OT>) -> Result<BrokerEventResult, AflError> {
         match event {
             Event::LoadInitial {
                 sender_id: _,
@@ -542,8 +573,8 @@ where
 
     fn handle_in_client(
         &mut self,
-        event: Event<I>,
-        /*client: &dyn EventManager<C, E, I, R>,*/ _state: &mut State<I, R>,
+        event: Event<I, OT>,
+        _state: &mut State<I, R, FT>,
         _corpus: &mut C,
     ) -> Result<(), AflError> {
         match event {
@@ -572,17 +603,16 @@ mod tests {
 
     use crate::events::Event;
     use crate::inputs::bytes::BytesInput;
-    use crate::observers::observer_serde::NamedSerdeAnyMap;
-    use crate::observers::{Observer, StdMapObserver};
+    use crate::observers::{Observer, ObserversTuple, StdMapObserver};
     use crate::serde_anymap::{Ptr, PtrMut};
+    use crate::tuples::{tuple_list, tuple_list_type, MatchNameAndType, Named};
 
     static mut MAP: [u32; 4] = [0; 4];
 
     #[test]
     fn test_event_serde() {
-        let mut map = NamedSerdeAnyMap::new();
         let obv = StdMapObserver::new("test", unsafe { &mut MAP });
-        map.insert(Box::new(obv), &"key".to_string());
+        let mut map = tuple_list!(obv);
 
         let i = BytesInput::new(vec![0]);
         let e = Event::NewTestcase {
@@ -594,19 +624,20 @@ mod tests {
 
         let j = serde_json::to_string(&e).unwrap();
 
-        let d: Event<BytesInput> = serde_json::from_str(&j).unwrap();
+        let d: Event<BytesInput, tuple_list_type!(StdMapObserver<u32>)> =
+            serde_json::from_str(&j).unwrap();
         match d {
             Event::NewTestcase {
                 sender_id: _,
                 input: _,
-                observers: obs,
+                observers,
                 corpus_count: _,
             } => {
-                let o = obs
+                let o = observers
                     .as_ref()
-                    .get::<StdMapObserver<u32>>(&"key".to_string())
+                    .match_name_type::<StdMapObserver<u32>>("test")
                     .unwrap();
-                assert_eq!("test".to_string(), *o.name());
+                assert_eq!("test", o.name());
             }
             _ => panic!("mistmatch".to_string()),
         };
diff --git a/afl/src/executors/inmemory.rs b/afl/src/executors/inmemory.rs
index 8ce1e4b0c6..eb9989b5dd 100644
--- a/afl/src/executors/inmemory.rs
+++ b/afl/src/executors/inmemory.rs
@@ -1,9 +1,9 @@
 use core::ffi::c_void;
 use core::ptr;
 
-use crate::executors::{Executor, ExitKind};
+use crate::executors::{Executor, ExitKind, HasObservers};
 use crate::inputs::{HasTargetBytes, Input};
-use crate::observers::observer_serde::NamedSerdeAnyMap;
+use crate::observers::ObserversTuple;
 use crate::AflError;
 
 /// The (unsafe) pointer to the current inmem executor, for the current run.
@@ -14,23 +14,25 @@ static mut CURRENT_INMEMORY_EXECUTOR_PTR: *const c_void = ptr::null();
 type HarnessFunction<I> = fn(&dyn Executor<I>, &[u8]) -> ExitKind;
 
 /// The inmem executor simply calls a target function, then returns afterwards.
-pub struct InMemoryExecutor<I>
+pub struct InMemoryExecutor<I, OT>
 where
     I: Input + HasTargetBytes,
+    OT: ObserversTuple,
 {
     harness: HarnessFunction<I>,
-    observers: NamedSerdeAnyMap,
+    observers: OT,
 }
 
-impl<I> Executor<I> for InMemoryExecutor<I>
+impl<I, OT> Executor<I> for InMemoryExecutor<I, OT>
 where
     I: Input + HasTargetBytes,
+    OT: ObserversTuple,
 {
     #[inline]
     fn run_target(&mut self, input: &I) -> Result<ExitKind, AflError> {
         let bytes = input.target_bytes();
         unsafe {
-            CURRENT_INMEMORY_EXECUTOR_PTR = self as *const InMemoryExecutor<I> as *const c_void;
+            CURRENT_INMEMORY_EXECUTOR_PTR = self as *const InMemoryExecutor<I, OT> as *const c_void;
         }
         let ret = (self.harness)(self, bytes.as_slice());
         unsafe {
@@ -38,30 +40,37 @@ where
         }
         Ok(ret)
     }
+}
 
+impl<I, OT> HasObservers<OT> for InMemoryExecutor<I, OT>
+where
+    I: Input + HasTargetBytes,
+    OT: ObserversTuple,
+{
     #[inline]
-    fn observers(&self) -> &NamedSerdeAnyMap {
+    fn observers(&self) -> &OT {
         &self.observers
     }
 
     #[inline]
-    fn observers_mut(&mut self) -> &mut NamedSerdeAnyMap {
+    fn observers_mut(&mut self) -> &mut OT {
         &mut self.observers
     }
 }
 
-impl<I> InMemoryExecutor<I>
+impl<I, OT> InMemoryExecutor<I, OT>
 where
     I: Input + HasTargetBytes,
+    OT: ObserversTuple,
 {
-    pub fn new(harness_fn: HarnessFunction<I>) -> Self {
+    pub fn new(harness_fn: HarnessFunction<I>, observers: OT) -> Self {
         #[cfg(feature = "std")]
         unsafe {
             os_signals::setup_crash_handlers::<I>();
         }
         Self {
             harness: harness_fn,
-            observers: NamedSerdeAnyMap::new(),
+            observers: observers,
         }
     }
 }
@@ -169,6 +178,7 @@ mod tests {
     use crate::executors::inmemory::InMemoryExecutor;
     use crate::executors::{Executor, ExitKind};
     use crate::inputs::{HasTargetBytes, Input, TargetBytes};
+    use crate::tuples::{tuple_list, tuple_list_type};
 
     use serde::{Deserialize, Serialize};
 
@@ -194,7 +204,7 @@ mod tests {
 
     #[test]
     fn test_inmem_exec() {
-        let mut in_mem_executor = InMemoryExecutor::new(test_harness_fn_nop);
+        let mut in_mem_executor = InMemoryExecutor::new(test_harness_fn_nop, tuple_list!());
         let mut input = NopInput {};
         assert!(in_mem_executor.run_target(&mut input).is_ok());
     }
diff --git a/afl/src/executors/mod.rs b/afl/src/executors/mod.rs
index 73f8c6e8fd..ea209b8dd0 100644
--- a/afl/src/executors/mod.rs
+++ b/afl/src/executors/mod.rs
@@ -1,10 +1,7 @@
 pub mod inmemory;
 
-use alloc::boxed::Box;
-
 use crate::inputs::Input;
-use crate::observers::observer_serde::NamedSerdeAnyMap;
-use crate::observers::Observer;
+use crate::observers::ObserversTuple;
 use crate::AflError;
 
 /// How an execution finished.
@@ -15,6 +12,29 @@ pub enum ExitKind {
     Timeout,
 }
 
+pub trait HasObservers<OT>
+where
+    OT: ObserversTuple,
+{
+    /// Get the linked observers
+    fn observers(&self) -> &OT;
+
+    /// Get the linked observers
+    fn observers_mut(&mut self) -> &mut OT;
+
+    /// Reset the state of all the observes linked to this executor
+    #[inline]
+    fn reset_observers(&mut self) -> Result<(), AflError> {
+        self.observers_mut().reset_all()
+    }
+
+    /// Run the post exec hook for all the observes linked to this executor
+    #[inline]
+    fn post_exec_observers(&mut self) -> Result<(), AflError> {
+        self.observers_mut().post_exec_all()
+    }
+}
+
 /// An executor takes the given inputs, and runs the harness/target.
 pub trait Executor<I>
 where
@@ -22,31 +42,4 @@ where
 {
     /// Instruct the target about the input and run
     fn run_target(&mut self, input: &I) -> Result<ExitKind, AflError>;
-
-    /// Get the linked observers
-    fn observers(&self) -> &NamedSerdeAnyMap;
-
-    /// Get the linked observers
-    fn observers_mut(&mut self) -> &mut NamedSerdeAnyMap;
-
-    /// Add a linked observer
-    fn add_observer(&mut self, observer: Box<dyn Observer>) {
-        let name = observer.name().clone();
-        self.observers_mut().insert(observer, &name);
-    }
-
-    /// Reset the state of all the observes linked to this executor
-    #[inline]
-    fn reset_observers(&mut self) -> Result<(), AflError> {
-        self.observers_mut().for_each_mut(|_, x| Ok(x.reset()?))?;
-        Ok(())
-    }
-
-    /// Run the post exec hook for all the observes linked to this executor
-    #[inline]
-    fn post_exec_observers(&mut self) -> Result<(), AflError> {
-        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 988e54f5be..4356e53b03 100644
--- a/afl/src/feedbacks/mod.rs
+++ b/afl/src/feedbacks/mod.rs
@@ -4,11 +4,11 @@ use alloc::vec::Vec;
 use core::marker::PhantomData;
 use num::Integer;
 
+use crate::corpus::Testcase;
 use crate::inputs::Input;
-use crate::observers::observer_serde::NamedSerdeAnyMap;
-use crate::observers::MapObserver;
+use crate::observers::{MapObserver, Observer, ObserversTuple};
+use crate::tuples::{MatchNameAndType, MatchType, Named, TupleList};
 use crate::AflError;
-use crate::{corpus::Testcase, observers::Observer};
 
 pub type MaxMapFeedback<T, O> = MapFeedback<T, MaxReducer<T>, O>;
 pub type MinMapFeedback<T, O> = MapFeedback<T, MinReducer<T>, O>;
@@ -19,12 +19,16 @@ pub type MinMapFeedback<T, O> = MapFeedback<T, MinReducer<T>, O>;
 /// Feedbacks evaluate the observers.
 /// Basically, they reduce the information provided by an observer to a value,
 /// indicating the "interestingness" of the last run.
-pub trait Feedback<I>
+pub trait Feedback<I>: Named + 'static
 where
     I: Input,
 {
     /// is_interesting should return the "Interestingness" from 0 to 255 (percent times 2.55)
-    fn is_interesting(&mut self, input: &I, observers: &NamedSerdeAnyMap) -> Result<u32, AflError>;
+    fn is_interesting<OT: ObserversTuple>(
+        &mut self,
+        input: &I,
+        observers: &OT,
+    ) -> Result<u32, AflError>;
 
     /// Append to the testcase the generated metadata in case of a new corpus item
     #[inline]
@@ -37,13 +41,82 @@ where
     fn discard_metadata(&mut self, _input: &I) -> Result<(), AflError> {
         Ok(())
     }
+}
 
-    /// The name of this feedback
-    fn name(&self) -> &String;
+pub trait FeedbacksTuple<I>: MatchType + MatchNameAndType
+where
+    I: Input,
+{
+    fn is_interesting_all<OT: ObserversTuple>(
+        &mut self,
+        input: &I,
+        observers: &OT,
+    ) -> Result<u32, AflError>;
+    fn append_metadata_all(&mut self, testcase: &mut Testcase<I>) -> Result<(), AflError>;
+    fn discard_metadata_all(&mut self, input: &I) -> Result<(), AflError>;
+    //fn for_each(&self, f: fn(&dyn Feedback<I>));
+    //fn for_each_mut(&mut self, f: fn(&mut dyn Feedback<I>));
+}
+
+impl<I> FeedbacksTuple<I> for ()
+where
+    I: Input,
+{
+    fn is_interesting_all<OT: ObserversTuple>(
+        &mut self,
+        input: &I,
+        observers: &OT,
+    ) -> Result<u32, AflError> {
+        Ok(0)
+    }
+    fn append_metadata_all(&mut self, testcase: &mut Testcase<I>) -> Result<(), AflError> {
+        Ok(())
+    }
+    fn discard_metadata_all(&mut self, input: &I) -> Result<(), AflError> {
+        Ok(())
+    }
+    //fn for_each(&self, f: fn(&dyn Feedback<I>)) {}
+    //fn for_each_mut(&mut self, f: fn(&mut dyn Feedback<I>)) {}
+}
+
+impl<Head, Tail, I> FeedbacksTuple<I> for (Head, Tail)
+where
+    Head: Feedback<I>,
+    Tail: FeedbacksTuple<I> + TupleList,
+    I: Input,
+{
+    fn is_interesting_all<OT: ObserversTuple>(
+        &mut self,
+        input: &I,
+        observers: &OT,
+    ) -> Result<u32, AflError> {
+        Ok(self.0.is_interesting(input, observers)?
+            + self.1.is_interesting_all(input, observers)?)
+    }
+
+    fn append_metadata_all(&mut self, testcase: &mut Testcase<I>) -> Result<(), AflError> {
+        self.0.append_metadata(testcase)?;
+        self.1.append_metadata_all(testcase)
+    }
+
+    fn discard_metadata_all(&mut self, input: &I) -> Result<(), AflError> {
+        self.0.discard_metadata(input)?;
+        self.1.discard_metadata_all(input)
+    }
+
+    /*fn for_each(&self, f: fn(&dyn Feedback<I>)) {
+        f(&self.0);
+        self.1.for_each(f)
+    }
+
+    fn for_each_mut(&mut self, f: fn(&mut dyn Feedback<I>)) {
+        f(self.0);
+        self.1.for_each_mut(f)
+    }*/
 }
 
 /// A Reducer function is used to aggregate values for the novelty search
-pub trait Reducer<T>
+pub trait Reducer<T>: 'static
 where
     T: Integer + Copy + 'static,
 {
@@ -102,7 +175,7 @@ where
     /// Contains information about untouched entries
     history_map: Vec<T>,
     /// Name identifier of this instance
-    name: String,
+    name: &'static str,
     /// Phantom Data of Reducer
     phantom: PhantomData<(R, O)>,
 }
@@ -114,14 +187,14 @@ where
     O: MapObserver<T> + 'static,
     I: Input,
 {
-    fn is_interesting(
+    fn is_interesting<OT: ObserversTuple>(
         &mut self,
         _input: &I,
-        observers: &NamedSerdeAnyMap,
+        observers: &OT,
     ) -> Result<u32, AflError> {
         let mut interesting = 0;
         // TODO optimize
-        let observer = observers.get::<O>(&self.name).unwrap();
+        let observer = observers.match_name_type::<O>(&self.name).unwrap();
         let size = observer.map().len();
         for i in 0..size {
             let history = self.history_map[i];
@@ -135,10 +208,17 @@ where
 
         Ok(interesting)
     }
+}
 
+impl<T, R, O> Named for MapFeedback<T, R, O>
+where
+    T: Integer + Default + Copy + 'static,
+    R: Reducer<T>,
+    O: MapObserver<T> + 'static,
+{
     #[inline]
-    fn name(&self) -> &String {
-        &self.name
+    fn name(&self) -> &str {
+        self.name
     }
 }
 
@@ -152,18 +232,18 @@ where
     pub fn new(name: &'static str, map_size: usize) -> Self {
         Self {
             history_map: vec![T::default(); map_size],
-            name: name.to_string(),
+            name: name,
             phantom: PhantomData,
         }
     }
 
-    pub fn new_with_observer(map_observer: &O) -> Self {
+    /*pub fn new_with_observer(map_observer: &O) -> Self {
         Self {
             history_map: vec![T::default(); map_observer.map().len()],
-            name: map_observer.name().to_string(),
+            name: map_observer.name(),
             phantom: PhantomData,
         }
-    }
+    }*/
 }
 
 impl<T, R, O> MapFeedback<T, R, O>
diff --git a/afl/src/lib.rs b/afl/src/lib.rs
index 4af4633494..0571ff0bde 100644
--- a/afl/src/lib.rs
+++ b/afl/src/lib.rs
@@ -19,6 +19,7 @@ pub mod mutators;
 pub mod observers;
 pub mod serde_anymap;
 pub mod stages;
+pub mod tuples;
 pub mod utils;
 
 use alloc::string::String;
diff --git a/afl/src/observers/mod.rs b/afl/src/observers/mod.rs
index 0901350791..a6be37e922 100644
--- a/afl/src/observers/mod.rs
+++ b/afl/src/observers/mod.rs
@@ -1,18 +1,14 @@
 extern crate num;
 
-use alloc::boxed::Box;
-use alloc::string::String;
-use core::any::Any;
 use serde::{Deserialize, Serialize};
 
-use crate::serde_anymap::{ArrayMut, SerdeAny};
+use crate::serde_anymap::ArrayMut;
+use crate::tuples::{MatchNameAndType, MatchType, Named, TupleList};
 use crate::AflError;
 
-// TODO register each observer in the Registry in new()
-
 /// Observers observe different information about the target.
 /// They can then be used by various sorts of feedback.
-pub trait Observer: SerdeAny + 'static {
+pub trait Observer: Named + serde::Serialize + serde::de::DeserializeOwned + 'static {
     /// The testcase finished execution, calculate any changes.
     #[inline]
     fn flush(&mut self) -> Result<(), AflError> {
@@ -25,11 +21,53 @@ pub trait Observer: SerdeAny + 'static {
     fn post_exec(&mut self) -> Result<(), AflError> {
         Ok(())
     }
-
-    fn name(&self) -> &String;
 }
 
-crate::create_serde_registry_for_trait!(observer_serde, crate::observers::Observer);
+pub trait ObserversTuple:
+    MatchNameAndType + MatchType + serde::Serialize + serde::de::DeserializeOwned
+{
+    fn reset_all(&mut self) -> Result<(), AflError>;
+    fn post_exec_all(&mut self) -> Result<(), AflError>;
+    //fn for_each(&self, f: fn(&dyn Observer));
+    //fn for_each_mut(&mut self, f: fn(&mut dyn Observer));
+}
+
+impl ObserversTuple for () {
+    fn reset_all(&mut self) -> Result<(), AflError> {
+        Ok(())
+    }
+    fn post_exec_all(&mut self) -> Result<(), AflError> {
+        Ok(())
+    }
+    //fn for_each(&self, f: fn(&dyn Observer)) { }
+    //fn for_each_mut(&mut self, f: fn(&mut dyn Observer)) { }
+}
+
+impl<Head, Tail> ObserversTuple for (Head, Tail)
+where
+    Head: Observer,
+    Tail: ObserversTuple + TupleList,
+{
+    fn reset_all(&mut self) -> Result<(), AflError> {
+        self.0.reset()?;
+        self.1.reset_all()
+    }
+
+    fn post_exec_all(&mut self) -> Result<(), AflError> {
+        self.0.post_exec()?;
+        self.1.post_exec_all()
+    }
+
+    /*fn for_each(&self, f: fn(&dyn Observer)) {
+        f(&self.0);
+        self.1.for_each(f)
+    }
+
+    fn for_each_mut(&mut self, f: fn(&mut dyn Observer)) {
+        f(&mut self.0);
+        self.1.for_each_mut(f)
+    }*/
+}
 
 /// A MapObserver observes the static map, as oftentimes used for afl-like coverage information
 pub trait MapObserver<T>
@@ -85,25 +123,15 @@ where
     fn reset(&mut self) -> Result<(), AflError> {
         self.reset_map()
     }
-
-    #[inline]
-    fn name(&self) -> &String {
-        &self.name
-    }
 }
 
-impl<T> SerdeAny for StdMapObserver<T>
+impl<T> Named for StdMapObserver<T>
 where
     T: Default + Copy + 'static + serde::Serialize + serde::de::DeserializeOwned,
 {
     #[inline]
-    fn as_any(&self) -> &dyn Any {
-        self
-    }
-
-    #[inline]
-    fn as_any_mut(&mut self) -> &mut dyn Any {
-        self
+    fn name(&self) -> &str {
+        self.name.as_str()
     }
 }
 
@@ -143,7 +171,6 @@ where
 {
     /// Creates a new MapObserver
     pub fn new(name: &'static str, map: &'static mut [T]) -> Self {
-        observer_serde::RegistryBuilder::register::<Self>();
         let initial = if map.len() > 0 { map[0] } else { T::default() };
         Self {
             map: ArrayMut::Cptr((map.as_mut_ptr(), map.len())),
@@ -154,7 +181,6 @@ where
 
     /// Creates a new MapObserver from a raw pointer
     pub fn new_from_ptr(name: &'static str, map_ptr: *mut T, len: usize) -> Self {
-        observer_serde::RegistryBuilder::register::<Self>();
         unsafe {
             let initial = if len > 0 { *map_ptr } else { T::default() };
             StdMapObserver {
@@ -166,6 +192,7 @@ where
     }
 }
 
+/*
 #[cfg(feature = "std")]
 #[cfg(test)]
 mod tests {
@@ -183,3 +210,4 @@ mod tests {
         assert_eq!(d.name(), o.name());
     }
 }
+*/
diff --git a/afl/src/stages/mod.rs b/afl/src/stages/mod.rs
index 202d539056..f63dc2b855 100644
--- a/afl/src/stages/mod.rs
+++ b/afl/src/stages/mod.rs
@@ -4,17 +4,22 @@ pub use mutational::StdMutationalStage;
 use crate::corpus::Corpus;
 use crate::engines::{Engine, State};
 use crate::events::EventManager;
-use crate::executors::Executor;
+use crate::executors::{Executor, HasObservers};
+use crate::feedbacks::FeedbacksTuple;
 use crate::inputs::Input;
+use crate::observers::ObserversTuple;
+use crate::tuples::{MatchType, TupleList};
 use crate::utils::Rand;
 use crate::AflError;
 
 /// A stage is one step in the fuzzing process.
 /// Multiple stages will be scheduled one by one for each input.
-pub trait Stage<EM, E, C, I, R>
+pub trait Stage<EM, E, OT, FT, C, I, R>
 where
-    EM: EventManager<C, E, I, R>,
-    E: Executor<I>,
+    EM: EventManager<C, E, OT, FT, I, R>,
+    E: Executor<I> + HasObservers<OT>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
     C: Corpus<I, R>,
     I: Input,
     R: Rand,
@@ -23,10 +28,96 @@ where
     fn perform(
         &mut self,
         rand: &mut R,
-        state: &mut State<I, R>,
+        state: &mut State<I, R, FT>,
         corpus: &mut C,
-        engine: &mut Engine<E, I>,
+        engine: &mut Engine<E, OT, I>,
         manager: &mut EM,
         corpus_idx: usize,
     ) -> Result<(), AflError>;
 }
+
+pub trait StagesTuple<EM, E, OT, FT, C, I, R>
+where
+    EM: EventManager<C, E, OT, FT, I, R>,
+    E: Executor<I> + HasObservers<OT>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
+    C: Corpus<I, R>,
+    I: Input,
+    R: Rand,
+{
+    fn perform_all(
+        &mut self,
+        rand: &mut R,
+        state: &mut State<I, R, FT>,
+        corpus: &mut C,
+        engine: &mut Engine<E, OT, I>,
+        manager: &mut EM,
+        corpus_idx: usize,
+    ) -> Result<(), AflError>;
+    fn for_each(&self, f: fn(&dyn Stage<EM, E, OT, FT, C, I, R>));
+    fn for_each_mut(&mut self, f: fn(&mut dyn Stage<EM, E, OT, FT, C, I, R>));
+}
+
+impl<EM, E, OT, FT, C, I, R> StagesTuple<EM, E, OT, FT, C, I, R> for ()
+where
+    EM: EventManager<C, E, OT, FT, I, R>,
+    E: Executor<I> + HasObservers<OT>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
+    C: Corpus<I, R>,
+    I: Input,
+    R: Rand,
+{
+    fn perform_all(
+        &mut self,
+        rand: &mut R,
+        state: &mut State<I, R, FT>,
+        corpus: &mut C,
+        engine: &mut Engine<E, OT, I>,
+        manager: &mut EM,
+        corpus_idx: usize,
+    ) -> Result<(), AflError> {
+        Ok(())
+    }
+    fn for_each(&self, f: fn(&dyn Stage<EM, E, OT, FT, C, I, R>)) {}
+    fn for_each_mut(&mut self, f: fn(&mut dyn Stage<EM, E, OT, FT, C, I, R>)) {}
+}
+
+impl<Head, Tail, EM, E, OT, FT, C, I, R> StagesTuple<EM, E, OT, FT, C, I, R> for (Head, Tail)
+where
+    Head: Stage<EM, E, OT, FT, C, I, R>,
+    Tail: StagesTuple<EM, E, OT, FT, C, I, R> + TupleList,
+    EM: EventManager<C, E, OT, FT, I, R>,
+    E: Executor<I> + HasObservers<OT>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
+    C: Corpus<I, R>,
+    I: Input,
+    R: Rand,
+{
+    fn perform_all(
+        &mut self,
+        rand: &mut R,
+        state: &mut State<I, R, FT>,
+        corpus: &mut C,
+        engine: &mut Engine<E, OT, I>,
+        manager: &mut EM,
+        corpus_idx: usize,
+    ) -> Result<(), AflError> {
+        self.0
+            .perform(rand, state, corpus, engine, manager, corpus_idx)?;
+        self.1
+            .perform_all(rand, state, corpus, engine, manager, corpus_idx)
+    }
+
+    fn for_each(&self, f: fn(&dyn Stage<EM, E, OT, FT, C, I, R>)) {
+        f(&self.0);
+        self.1.for_each(f)
+    }
+
+    fn for_each_mut(&mut self, f: fn(&mut dyn Stage<EM, E, OT, FT, C, I, R>)) {
+        f(&mut self.0);
+        self.1.for_each_mut(f)
+    }
+}
diff --git a/afl/src/stages/mutational.rs b/afl/src/stages/mutational.rs
index a7d79a9051..804326e020 100644
--- a/afl/src/stages/mutational.rs
+++ b/afl/src/stages/mutational.rs
@@ -1,9 +1,11 @@
 use core::marker::PhantomData;
 
 use crate::events::EventManager;
-use crate::executors::Executor;
+use crate::executors::{Executor, HasObservers};
+use crate::feedbacks::FeedbacksTuple;
 use crate::inputs::Input;
 use crate::mutators::Mutator;
+use crate::observers::ObserversTuple;
 use crate::stages::Corpus;
 use crate::stages::{Engine, Stage};
 use crate::utils::Rand;
@@ -17,11 +19,13 @@ use crate::serde_anymap::{Ptr, PtrMut};
 /// A Mutational stage is the stage in a fuzzing run that mutates inputs.
 /// Mutational stages will usually have a range of mutations that are
 /// being applied to the input one by one, between executions.
-pub trait MutationalStage<M, EM, E, C, I, R>: Stage<EM, E, C, I, R>
+pub trait MutationalStage<M, EM, E, OT, FT, C, I, R>: Stage<EM, E, OT, FT, C, I, R>
 where
     M: Mutator<C, I, R>,
-    EM: EventManager<C, E, I, R>,
-    E: Executor<I>,
+    EM: EventManager<C, E, OT, FT, I, R>,
+    E: Executor<I> + HasObservers<OT>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
     C: Corpus<I, R>,
     I: Input,
     R: Rand,
@@ -43,9 +47,9 @@ where
     fn perform_mutational(
         &mut self,
         rand: &mut R,
-        state: &mut State<I, R>,
+        state: &mut State<I, R, FT>,
         corpus: &mut C,
-        engine: &mut Engine<E, I>,
+        engine: &mut Engine<E, OT, I>,
         manager: &mut EM,
         corpus_idx: usize,
     ) -> Result<(), AflError> {
@@ -82,24 +86,29 @@ where
 }
 
 /// The default mutational stage
-pub struct StdMutationalStage<M, EM, E, C, I, R>
+pub struct StdMutationalStage<M, EM, E, OT, FT, C, I, R>
 where
     M: Mutator<C, I, R>,
-    EM: EventManager<C, E, I, R>,
-    E: Executor<I>,
+    EM: EventManager<C, E, OT, FT, I, R>,
+    E: Executor<I> + HasObservers<OT>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
     C: Corpus<I, R>,
     I: Input,
     R: Rand,
 {
     mutator: M,
-    phantom: PhantomData<(EM, E, C, I, R)>,
+    phantom: PhantomData<(EM, E, OT, FT, C, I, R)>,
 }
 
-impl<M, EM, E, C, I, R> MutationalStage<M, EM, E, C, I, R> for StdMutationalStage<M, EM, E, C, I, R>
+impl<M, EM, E, OT, FT, C, I, R> MutationalStage<M, EM, E, OT, FT, C, I, R>
+    for StdMutationalStage<M, EM, E, OT, FT, C, I, R>
 where
     M: Mutator<C, I, R>,
-    EM: EventManager<C, E, I, R>,
-    E: Executor<I>,
+    EM: EventManager<C, E, OT, FT, I, R>,
+    E: Executor<I> + HasObservers<OT>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
     C: Corpus<I, R>,
     I: Input,
     R: Rand,
@@ -117,11 +126,14 @@ where
     }
 }
 
-impl<M, EM, E, C, I, R> Stage<EM, E, C, I, R> for StdMutationalStage<M, EM, E, C, I, R>
+impl<M, EM, E, OT, FT, C, I, R> Stage<EM, E, OT, FT, C, I, R>
+    for StdMutationalStage<M, EM, E, OT, FT, C, I, R>
 where
     M: Mutator<C, I, R>,
-    EM: EventManager<C, E, I, R>,
-    E: Executor<I>,
+    EM: EventManager<C, E, OT, FT, I, R>,
+    E: Executor<I> + HasObservers<OT>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
     C: Corpus<I, R>,
     I: Input,
     R: Rand,
@@ -130,9 +142,9 @@ where
     fn perform(
         &mut self,
         rand: &mut R,
-        state: &mut State<I, R>,
+        state: &mut State<I, R, FT>,
         corpus: &mut C,
-        engine: &mut Engine<E, I>,
+        engine: &mut Engine<E, OT, I>,
         manager: &mut EM,
         corpus_idx: usize,
     ) -> Result<(), AflError> {
@@ -140,11 +152,13 @@ where
     }
 }
 
-impl<M, EM, E, C, I, R> StdMutationalStage<M, EM, E, C, I, R>
+impl<M, EM, E, OT, FT, C, I, R> StdMutationalStage<M, EM, E, OT, FT, C, I, R>
 where
     M: Mutator<C, I, R>,
-    EM: EventManager<C, E, I, R>,
-    E: Executor<I>,
+    EM: EventManager<C, E, OT, FT, I, R>,
+    E: Executor<I> + HasObservers<OT>,
+    OT: ObserversTuple,
+    FT: FeedbacksTuple<I>,
     C: Corpus<I, R>,
     I: Input,
     R: Rand,
diff --git a/afl/src/tuples.rs b/afl/src/tuples.rs
index 2972a9723e..d7209b8bab 100644
--- a/afl/src/tuples.rs
+++ b/afl/src/tuples.rs
@@ -1,16 +1,21 @@
-use tuple_list::TupleList;
-use tuple_list::tuple_list;
-use core::any::{TypeId, Any};
+pub use tuple_list::tuple_list;
+pub use tuple_list::tuple_list_type;
+pub use tuple_list::TupleList;
+
+use core::any::TypeId;
 
 pub trait HasLen {
     fn len(&self) -> usize;
 }
 
 impl HasLen for () {
-    fn len(&self) -> usize { 0 }
+    fn len(&self) -> usize {
+        0
+    }
 }
- 
-impl<Head, Tail> HasLen for (Head, Tail) where
+
+impl<Head, Tail> HasLen for (Head, Tail)
+where
     Tail: TupleList + HasLen,
 {
     fn len(&self) -> usize {
@@ -20,13 +25,20 @@ impl<Head, Tail> HasLen for (Head, Tail) where
 
 pub trait MatchFirstType {
     fn match_first_type<T: 'static>(&self) -> Option<&T>;
+    fn match_first_type_mut<T: 'static>(&mut self) -> Option<&mut T>;
 }
 
 impl MatchFirstType for () {
-    fn match_first_type<T: 'static>(&self) -> Option<&T> { None }
+    fn match_first_type<T: 'static>(&self) -> Option<&T> {
+        None
+    }
+    fn match_first_type_mut<T: 'static>(&mut self) -> Option<&mut T> {
+        None
+    }
 }
- 
-impl<Head, Tail> MatchFirstType for (Head, Tail) where
+
+impl<Head, Tail> MatchFirstType for (Head, Tail)
+where
     Head: 'static,
     Tail: TupleList + MatchFirstType,
 {
@@ -37,17 +49,32 @@ impl<Head, Tail> MatchFirstType for (Head, Tail) where
             self.1.match_first_type::<T>()
         }
     }
+
+    fn match_first_type_mut<T: 'static>(&mut self) -> Option<&mut T> {
+        if TypeId::of::<T>() == TypeId::of::<Head>() {
+            unsafe { (&mut self.0 as *mut _ as *mut T).as_mut() }
+        } else {
+            self.1.match_first_type_mut::<T>()
+        }
+    }
 }
 
 pub trait MatchType {
     fn match_type<T: 'static>(&self, f: fn(t: &T));
+    fn match_type_mut<T: 'static>(&mut self, f: fn(t: &mut T));
 }
 
 impl MatchType for () {
-    fn match_type<T: 'static>(&self, f: fn(t: &T)) { () }
+    fn match_type<T: 'static>(&self, f: fn(t: &T)) {
+        ()
+    }
+    fn match_type_mut<T: 'static>(&mut self, f: fn(t: &mut T)) {
+        ()
+    }
 }
- 
-impl<Head, Tail> MatchType for (Head, Tail) where
+
+impl<Head, Tail> MatchType for (Head, Tail)
+where
     Head: 'static,
     Tail: TupleList + MatchType,
 {
@@ -57,21 +84,35 @@ impl<Head, Tail> MatchType for (Head, Tail) where
         }
         self.1.match_type::<T>(f);
     }
+
+    fn match_type_mut<T: 'static>(&mut self, f: fn(t: &mut T)) {
+        if TypeId::of::<T>() == TypeId::of::<Head>() {
+            f(unsafe { (&mut self.0 as *mut _ as *mut T).as_mut() }.unwrap());
+        }
+        self.1.match_type_mut::<T>(f);
+    }
 }
 
 pub trait Named {
-    fn name(&self) -> &'static str;
+    fn name(&self) -> &str;
 }
 
 pub trait MatchNameAndType {
     fn match_name_type<T: 'static>(&self, name: &'static str) -> Option<&T>;
+    fn match_name_type_mut<T: 'static>(&mut self, name: &'static str) -> Option<&mut T>;
 }
 
 impl MatchNameAndType for () {
-    fn match_name_type<T: 'static>(&self, name: &'static str) -> Option<&T> { None }
+    fn match_name_type<T: 'static>(&self, name: &'static str) -> Option<&T> {
+        None
+    }
+    fn match_name_type_mut<T: 'static>(&mut self, name: &'static str) -> Option<&mut T> {
+        None
+    }
 }
- 
-impl<Head, Tail> MatchNameAndType for (Head, Tail) where
+
+impl<Head, Tail> MatchNameAndType for (Head, Tail)
+where
     Head: 'static + Named,
     Tail: TupleList + MatchNameAndType,
 {
@@ -82,6 +123,14 @@ impl<Head, Tail> MatchNameAndType for (Head, Tail) where
             self.1.match_name_type::<T>(name)
         }
     }
+
+    fn match_name_type_mut<T: 'static>(&mut self, name: &'static str) -> Option<&mut T> {
+        if TypeId::of::<T>() == TypeId::of::<Head>() && name == self.0.name() {
+            unsafe { (&mut self.0 as *mut _ as *mut T).as_mut() }
+        } else {
+            self.1.match_name_type_mut::<T>(name)
+        }
+    }
 }
 
 pub trait Prepend<T>: TupleList {
@@ -91,35 +140,41 @@ pub trait Prepend<T>: TupleList {
 }
 
 /// Implement prepend for tuple list.
-impl<Tail, T> Prepend<T> for Tail where Tail: TupleList {
+impl<Tail, T> Prepend<T> for Tail
+where
+    Tail: TupleList,
+{
     type PreprendResult = Self;
 
     fn prepend(self, value: T) -> (T, Self::PreprendResult) {
         (value, self)
     }
 }
- 
+
 pub trait Append<T>: TupleList {
     type AppendResult: TupleList;
- 
+
     fn append(self, value: T) -> Self::AppendResult;
 }
- 
+
 /// Implement append for an empty tuple list.
 impl<T> Append<T> for () {
     type AppendResult = (T, ());
- 
-    fn append(self, value: T) -> Self::AppendResult { (value, ()) }
+
+    fn append(self, value: T) -> Self::AppendResult {
+        (value, ())
+    }
 }
- 
+
 /// Implement append for non-empty tuple list.
-impl<Head, Tail, T> Append<T> for (Head, Tail) where
+impl<Head, Tail, T> Append<T> for (Head, Tail)
+where
     Self: TupleList,
     Tail: Append<T>,
     (Head, Tail::AppendResult): TupleList,
 {
     type AppendResult = (Head, Tail::AppendResult);
- 
+
     fn append(self, value: T) -> Self::AppendResult {
         let (head, tail) = self;
         return (head, tail.append(value));
@@ -134,13 +189,13 @@ trait PlusOne {
 }
 impl PlusOne for i32    { fn plus_one(&mut self) { *self += 1; } }
 impl PlusOne for String { fn plus_one(&mut self) { self.push('1'); } }
- 
+
 // Now we have to implement trait for an empty tuple,
 // thus defining initial condition.
 impl PlusOne for () {
     fn plus_one(&mut self) {}
 }
- 
+
 // Now we can implement trait for a non-empty tuple list,
 // thus defining recursion and supporting tuple lists of arbitrary length.
 impl<Head, Tail> PlusOne for (Head, Tail) where
diff --git a/fuzzers/libfuzzer/src/lib.rs b/fuzzers/libfuzzer/src/lib.rs
index c4e17e4923..70c020a273 100644
--- a/fuzzers/libfuzzer/src/lib.rs
+++ b/fuzzers/libfuzzer/src/lib.rs
@@ -22,8 +22,9 @@ use afl::mutators::HasMaxSize;
 use afl::observers::StdMapObserver;
 use afl::stages::mutational::StdMutationalStage;
 use afl::utils::StdRand;
+use afl::tuples::tuple_list;
 
-// const MAP_SIZE: usize = 65536;
+const MAP_SIZE: usize = 65536;
 
 #[no_mangle]
 extern "C" {
@@ -59,18 +60,12 @@ pub extern "C" fn afl_libfuzzer_main() {
         StdMapObserver::new_from_ptr(&NAME_COV_MAP, unsafe { __lafl_edges_map }, unsafe {
             __lafl_max_edges_size as usize
         });
-    let edges_feedback = MaxMapFeedback::new_with_observer(&edges_observer);
-
-    let mut executor = InMemoryExecutor::new(harness);
-    let mut state = State::new();
-    executor.add_observer(Box::new(edges_observer));
-    state.add_feedback(Box::new(edges_feedback));
+    let edges_feedback = MaxMapFeedback::<u8, StdMapObserver<u8>>::new(&NAME_COV_MAP, MAP_SIZE);
 
+    let executor = InMemoryExecutor::new(harness, tuple_list!(edges_observer));
+    let mut state = State::new(tuple_list!(edges_feedback));
+ 
     let mut engine = Engine::new(executor);
-    let mut mutator = HavocBytesMutator::new_default();
-    mutator.set_max_size(4096);
-
-    let stage = StdMutationalStage::new(mutator);
 
     state
         .generate_initial_inputs(
@@ -83,9 +78,11 @@ pub extern "C" fn afl_libfuzzer_main() {
         )
         .expect("Failed to load initial inputs");
 
-    let mut fuzzer = StdFuzzer::new();
+    let mut mutator = HavocBytesMutator::new_default();
+    mutator.set_max_size(4096);
 
-    fuzzer.add_stage(Box::new(stage));
+    let stage = StdMutationalStage::new(mutator);
+    let mut fuzzer = StdFuzzer::new(tuple_list!(stage));
 
     fuzzer
         .fuzz_loop(&mut rand, &mut state, &mut corpus, &mut engine, &mut events)