diff --git a/README.md b/README.md
index db03861a9..51daae95a 100644
--- a/README.md
+++ b/README.md
@@ -113,7 +113,7 @@ necsim-rust consists of the following crates:
         - core/: `necsim-partitioning-core` declares the core partitioning traits
         - monolithic/: `necsim-partitioning-monolithic` implements monolithic, i.e. non-parallel partitioning
         - mpi/: `necsim-partitioning-mpi` implements the MPI-based partitioning backend
-        - threads/: `necsim-partitioning-threads` implements the multithreading partitioning backend
+        - threads/: `necsim-partitioning-threads` implements the multithreading-based partitioning backend
 - rustcoalescence/: `rustcoalescence` provides the command-line interface.
     - scenarios/: `rustcoalescence-scenarios` contains the glue code to put together the cogs for the built-in scenarios. It is specifically built only for reducing code duplication in rustcoalescence, not for giving a minimal example of how to construct a simulation.
     - algorithms/:
diff --git a/docs/simulate.ron b/docs/simulate.ron
index e3f19cfe5..a8cbf5e79 100644
--- a/docs/simulate.ron
+++ b/docs/simulate.ron
@@ -676,7 +676,8 @@
              * optional, default = "100ms" */
             progress: (DurationString),
         )
-        /* the simulation is divided up across multiple threads
+        /* the simulation is divided up across multiple threads, which
+            communicate using message passing and may share immutable data
          * multi-threaded, single-process
          * requires the `threads-partitioning` feature */
       | Threads(
diff --git a/necsim/core/src/landscape/location.rs b/necsim/core/src/landscape/location.rs
index 6bcc520a6..7d8b2cf26 100644
--- a/necsim/core/src/landscape/location.rs
+++ b/necsim/core/src/landscape/location.rs
@@ -1,7 +1,5 @@
 use serde::{Deserialize, Serialize};
 
-use crate::cogs::Backup;
-
 #[allow(clippy::module_name_repetitions)]
 #[derive(
     Eq, PartialEq, PartialOrd, Ord, Clone, Hash, Debug, Serialize, Deserialize, TypeLayout,
@@ -15,13 +13,6 @@ pub struct Location {
     y: u32,
 }
 
-#[contract_trait]
-impl Backup for Location {
-    unsafe fn backup_unchecked(&self) -> Self {
-        self.clone()
-    }
-}
-
 impl Location {
     #[must_use]
     pub const fn new(x: u32, y: u32) -> Self {
diff --git a/necsim/core/src/lineage.rs b/necsim/core/src/lineage.rs
index 398973fd0..57e85b9c3 100644
--- a/necsim/core/src/lineage.rs
+++ b/necsim/core/src/lineage.rs
@@ -54,13 +54,6 @@ impl<'de> Deserialize<'de> for GlobalLineageReference {
     }
 }
 
-#[contract_trait]
-impl Backup for GlobalLineageReference {
-    unsafe fn backup_unchecked(&self) -> Self {
-        GlobalLineageReference(self.0)
-    }
-}
-
 impl<M: MathsCore, H: Habitat<M>> LineageReference<M, H> for GlobalLineageReference {}
 
 #[allow(clippy::module_name_repetitions)]
diff --git a/necsim/impls/no-std/src/alias/packed.rs b/necsim/impls/no-std/src/alias/packed.rs
index 9f0e20259..7548d7529 100644
--- a/necsim/impls/no-std/src/alias/packed.rs
+++ b/necsim/impls/no-std/src/alias/packed.rs
@@ -119,22 +119,29 @@ impl<E: Copy + PartialEq> AliasMethodSamplerAtom<E> {
         }
     }
 
+    pub fn sample_event<M: MathsCore, G: RngCore<M>>(
+        alias_samplers: &[AliasMethodSamplerAtom<E>],
+        rng: &mut G,
+    ) -> E {
+        Self::sample_event_with_cdf_limit(alias_samplers, rng, ClosedUnitF64::one())
+    }
+
     #[allow(clippy::no_effect_underscore_binding)]
     #[debug_requires(!alias_samplers.is_empty(), "alias_samplers is non-empty")]
     #[debug_ensures(
         old(alias_samplers).iter().map(|s| s.e).any(|e| e == ret),
         "returns one of the weighted events"
     )]
-    pub fn sample_event<M: MathsCore, G: RngCore<M>>(
+    pub fn sample_event_with_cdf_limit<M: MathsCore, G: RngCore<M>>(
         alias_samplers: &[AliasMethodSamplerAtom<E>],
         rng: &mut G,
-        factor: ClosedUnitF64,
+        limit: ClosedUnitF64,
     ) -> E {
         use necsim_core::cogs::RngSampler;
 
         #[allow(clippy::cast_precision_loss)]
         let f =
-            rng.sample_uniform_closed_open().get() * factor.get() * (alias_samplers.len() as f64);
+            rng.sample_uniform_closed_open().get() * limit.get() * (alias_samplers.len() as f64);
 
         #[allow(
             clippy::cast_precision_loss,
diff --git a/necsim/impls/no-std/src/array2d.rs b/necsim/impls/no-std/src/array2d.rs
index 48a820fb0..f55364d98 100644
--- a/necsim/impls/no-std/src/array2d.rs
+++ b/necsim/impls/no-std/src/array2d.rs
@@ -464,7 +464,7 @@ impl<T, B: ArrayBackend<T>> Array2D<T, B> {
     /// # fn main() -> Result<(), Error> {
     /// let rows = vec![vec![1, 2, 3], vec![4, 5, 6]];
     /// let array = VecArray2D::from_rows(&rows)?;
-    /// assert_eq!(array.into_row_major_inner(), vec![1, 2, 3, 4, 5, 6]);
+    /// assert_eq!(array.into_row_major_backend(), vec![1, 2, 3, 4, 5, 6]);
     /// # Ok(())
     /// # }
     /// ```
@@ -472,7 +472,7 @@ impl<T, B: ArrayBackend<T>> Array2D<T, B> {
     /// [`Array2D`]: struct.Array2D.html
     /// [row major order]: https://en.wikipedia.org/wiki/Row-_and_column-major_order
     #[must_use]
-    pub fn into_row_major_inner(self) -> B {
+    pub fn into_row_major_backend(self) -> B {
         self.array
     }
 
diff --git a/necsim/impls/no-std/src/cogs/active_lineage_sampler/alias/sampler/indexed/tests.rs b/necsim/impls/no-std/src/cogs/active_lineage_sampler/alias/sampler/indexed/tests.rs
index 04d554d8e..da31ab406 100644
--- a/necsim/impls/no-std/src/cogs/active_lineage_sampler/alias/sampler/indexed/tests.rs
+++ b/necsim/impls/no-std/src/cogs/active_lineage_sampler/alias/sampler/indexed/tests.rs
@@ -1100,11 +1100,4 @@ impl RngCore<IntrinsicsMathsCore> for DummyRng {
         self.0.pop().unwrap()
     }
 }
-
-#[contract_trait]
-impl Backup for DummyRng {
-    unsafe fn backup_unchecked(&self) -> Self {
-        Self(self.0.clone())
-    }
-}
 // GRCOV_EXCL_STOP
diff --git a/necsim/impls/no-std/src/cogs/active_lineage_sampler/alias/sampler/stack/tests.rs b/necsim/impls/no-std/src/cogs/active_lineage_sampler/alias/sampler/stack/tests.rs
index 505bf295c..9bc1b6017 100644
--- a/necsim/impls/no-std/src/cogs/active_lineage_sampler/alias/sampler/stack/tests.rs
+++ b/necsim/impls/no-std/src/cogs/active_lineage_sampler/alias/sampler/stack/tests.rs
@@ -598,11 +598,4 @@ impl RngCore<IntrinsicsMathsCore> for DummyRng {
         self.0.pop().unwrap()
     }
 }
-
-#[contract_trait]
-impl Backup for DummyRng {
-    unsafe fn backup_unchecked(&self) -> Self {
-        Self(self.0.clone())
-    }
-}
 // GRCOV_EXCL_STOP
diff --git a/necsim/impls/no-std/src/cogs/coalescence_sampler/independent.rs b/necsim/impls/no-std/src/cogs/coalescence_sampler/independent.rs
index f15e3f672..3c417d07f 100644
--- a/necsim/impls/no-std/src/cogs/coalescence_sampler/independent.rs
+++ b/necsim/impls/no-std/src/cogs/coalescence_sampler/independent.rs
@@ -1,9 +1,7 @@
 use core::marker::PhantomData;
 
 use necsim_core::{
-    cogs::{
-        coalescence_sampler::CoalescenceRngSample, Backup, CoalescenceSampler, Habitat, MathsCore,
-    },
+    cogs::{coalescence_sampler::CoalescenceRngSample, CoalescenceSampler, Habitat, MathsCore},
     landscape::{IndexedLocation, Location},
     lineage::LineageInteraction,
 };
@@ -25,9 +23,8 @@ impl<M: MathsCore, H: Habitat<M>> Default for IndependentCoalescenceSampler<M, H
     }
 }
 
-#[contract_trait]
-impl<M: MathsCore, H: Habitat<M>> Backup for IndependentCoalescenceSampler<M, H> {
-    unsafe fn backup_unchecked(&self) -> Self {
+impl<M: MathsCore, H: Habitat<M>> Clone for IndependentCoalescenceSampler<M, H> {
+    fn clone(&self) -> Self {
         Self(PhantomData::<(M, H)>)
     }
 }
diff --git a/necsim/impls/no-std/src/cogs/dispersal_sampler/almost_infinite_clark2dt.rs b/necsim/impls/no-std/src/cogs/dispersal_sampler/almost_infinite_clark2dt.rs
index 10b553abd..7858b7a1a 100644
--- a/necsim/impls/no-std/src/cogs/dispersal_sampler/almost_infinite_clark2dt.rs
+++ b/necsim/impls/no-std/src/cogs/dispersal_sampler/almost_infinite_clark2dt.rs
@@ -1,7 +1,7 @@
 use core::marker::PhantomData;
 
 use necsim_core::{
-    cogs::{Backup, DispersalSampler, MathsCore, RngCore, RngSampler, SeparableDispersalSampler},
+    cogs::{DispersalSampler, MathsCore, RngCore, RngSampler, SeparableDispersalSampler},
     landscape::Location,
 };
 use necsim_core_bond::{ClosedUnitF64, NonNegativeF64, PositiveF64};
@@ -9,7 +9,7 @@ use necsim_core_bond::{ClosedUnitF64, NonNegativeF64, PositiveF64};
 use crate::cogs::habitat::almost_infinite::AlmostInfiniteHabitat;
 
 #[allow(clippy::module_name_repetitions)]
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 #[cfg_attr(feature = "cuda", derive(rust_cuda::lend::LendRustToCuda))]
 #[cfg_attr(feature = "cuda", cuda(free = "M", free = "G"))]
 pub struct AlmostInfiniteClark2DtDispersalSampler<M: MathsCore, G: RngCore<M>> {
@@ -68,9 +68,8 @@ impl<M: MathsCore, G: RngCore<M>> AlmostInfiniteClark2DtDispersalSampler<M, G> {
     }
 }
 
-#[contract_trait]
-impl<M: MathsCore, G: RngCore<M>> Backup for AlmostInfiniteClark2DtDispersalSampler<M, G> {
-    unsafe fn backup_unchecked(&self) -> Self {
+impl<M: MathsCore, G: RngCore<M>> Clone for AlmostInfiniteClark2DtDispersalSampler<M, G> {
+    fn clone(&self) -> Self {
         Self {
             shape_u: self.shape_u,
             tail_p: self.tail_p,
diff --git a/necsim/impls/no-std/src/cogs/dispersal_sampler/almost_infinite_normal.rs b/necsim/impls/no-std/src/cogs/dispersal_sampler/almost_infinite_normal.rs
index 41ba5f478..ecd9fb2d0 100644
--- a/necsim/impls/no-std/src/cogs/dispersal_sampler/almost_infinite_normal.rs
+++ b/necsim/impls/no-std/src/cogs/dispersal_sampler/almost_infinite_normal.rs
@@ -1,7 +1,7 @@
 use core::marker::PhantomData;
 
 use necsim_core::{
-    cogs::{Backup, DispersalSampler, MathsCore, RngCore, SeparableDispersalSampler},
+    cogs::{DispersalSampler, MathsCore, RngCore, SeparableDispersalSampler},
     landscape::Location,
 };
 use necsim_core_bond::{ClosedUnitF64, NonNegativeF64};
@@ -9,7 +9,7 @@ use necsim_core_bond::{ClosedUnitF64, NonNegativeF64};
 use crate::cogs::habitat::almost_infinite::AlmostInfiniteHabitat;
 
 #[allow(clippy::module_name_repetitions)]
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 #[cfg_attr(feature = "cuda", derive(rust_cuda::lend::LendRustToCuda))]
 #[cfg_attr(feature = "cuda", cuda(free = "M", free = "G"))]
 pub struct AlmostInfiniteNormalDispersalSampler<M: MathsCore, G: RngCore<M>> {
@@ -39,9 +39,8 @@ impl<M: MathsCore, G: RngCore<M>> AlmostInfiniteNormalDispersalSampler<M, G> {
     }
 }
 
-#[contract_trait]
-impl<M: MathsCore, G: RngCore<M>> Backup for AlmostInfiniteNormalDispersalSampler<M, G> {
-    unsafe fn backup_unchecked(&self) -> Self {
+impl<M: MathsCore, G: RngCore<M>> Clone for AlmostInfiniteNormalDispersalSampler<M, G> {
+    fn clone(&self) -> Self {
         Self {
             sigma: self.sigma,
             self_dispersal: self.self_dispersal,
diff --git a/necsim/impls/no-std/src/cogs/dispersal_sampler/in_memory/packed_alias/dispersal.rs b/necsim/impls/no-std/src/cogs/dispersal_sampler/in_memory/packed_alias/dispersal.rs
index b90e95bba..f8c3e0697 100644
--- a/necsim/impls/no-std/src/cogs/dispersal_sampler/in_memory/packed_alias/dispersal.rs
+++ b/necsim/impls/no-std/src/cogs/dispersal_sampler/in_memory/packed_alias/dispersal.rs
@@ -4,7 +4,6 @@ use necsim_core::{
     cogs::{DispersalSampler, Habitat, MathsCore, RngCore},
     landscape::Location,
 };
-use necsim_core_bond::ClosedUnitF64;
 
 use crate::alias::packed::AliasMethodSamplerAtom;
 
@@ -38,11 +37,8 @@ impl<M: MathsCore, H: Habitat<M>, G: RngCore<M>> DispersalSampler<M, H, G>
         let alias_dispersals_at_location =
             unsafe { &self.alias_dispersal_buffer.get_unchecked(alias_range) };
 
-        let dispersal_target_index: usize = AliasMethodSamplerAtom::sample_event(
-            alias_dispersals_at_location,
-            rng,
-            ClosedUnitF64::one(),
-        );
+        let dispersal_target_index: usize =
+            AliasMethodSamplerAtom::sample_event(alias_dispersals_at_location, rng);
 
         #[allow(clippy::cast_possible_truncation)]
         Location::new(
diff --git a/necsim/impls/no-std/src/cogs/dispersal_sampler/in_memory/packed_separable_alias/dispersal.rs b/necsim/impls/no-std/src/cogs/dispersal_sampler/in_memory/packed_separable_alias/dispersal.rs
index ae848585d..09b9de4e8 100644
--- a/necsim/impls/no-std/src/cogs/dispersal_sampler/in_memory/packed_separable_alias/dispersal.rs
+++ b/necsim/impls/no-std/src/cogs/dispersal_sampler/in_memory/packed_separable_alias/dispersal.rs
@@ -29,18 +29,15 @@ impl<M: MathsCore, H: Habitat<M>, G: RngCore<M>> DispersalSampler<M, H, G>
                 .unwrap_unchecked()
         };
 
-        // Safe by the construction of `InMemoryPackedAliasDispersalSampler`
+        // Safe by the construction of `InMemoryPackedSeparableAliasDispersalSampler`
         let alias_dispersals_at_location = unsafe {
             &self
                 .alias_dispersal_buffer
                 .get_unchecked(alias_range.start..alias_range.end)
         };
 
-        let dispersal_target_index: usize = AliasMethodSamplerAtom::sample_event(
-            alias_dispersals_at_location,
-            rng,
-            ClosedUnitF64::one(),
-        );
+        let dispersal_target_index: usize =
+            AliasMethodSamplerAtom::sample_event(alias_dispersals_at_location, rng);
 
         #[allow(clippy::cast_possible_truncation)]
         Location::new(
@@ -82,7 +79,7 @@ impl<M: MathsCore, H: Habitat<M>, G: RngCore<M>> SeparableDispersalSampler<M, H,
                 .unwrap_unchecked()
         };
 
-        // Safe by the construction of `InMemoryPackedAliasDispersalSampler`
+        // Safe by the construction of `InMemoryPackedSeparableAliasDispersalSampler`
         let alias_dispersals_at_location = unsafe {
             &self
                 .alias_dispersal_buffer
@@ -90,8 +87,8 @@ impl<M: MathsCore, H: Habitat<M>, G: RngCore<M>> SeparableDispersalSampler<M, H,
         };
 
         // Since the atoms are pre-sorted s.t. all self-dispersal is on the right,
-        //  exclude it by providing 1-sd as the index sampling factor
-        let mut dispersal_target_index: usize = AliasMethodSamplerAtom::sample_event(
+        //  we can exclude sel-dispersal by providing 1-sd as the CDF limit
+        let mut dispersal_target_index: usize = AliasMethodSamplerAtom::sample_event_with_cdf_limit(
             alias_dispersals_at_location,
             rng,
             self_dispersal.self_dispersal.one_minus(),
@@ -121,10 +118,15 @@ impl<M: MathsCore, H: Habitat<M>, G: RngCore<M>> SeparableDispersalSampler<M, H,
         location: &Location,
         habitat: &H,
     ) -> ClosedUnitF64 {
-        self.self_dispersal[(
-            location.y().wrapping_sub(habitat.get_extent().origin().y()) as usize,
-            location.x().wrapping_sub(habitat.get_extent().origin().x()) as usize,
-        )]
-            .self_dispersal
+        // Only safe as trait precondition that `location` is inside `habitat`
+        unsafe {
+            self.self_dispersal
+                .get(
+                    location.y().wrapping_sub(habitat.get_extent().origin().y()) as usize,
+                    location.x().wrapping_sub(habitat.get_extent().origin().x()) as usize,
+                )
+                .unwrap_unchecked()
+        }
+        .self_dispersal
     }
 }
diff --git a/necsim/impls/no-std/src/cogs/dispersal_sampler/in_memory/packed_separable_alias/mod.rs b/necsim/impls/no-std/src/cogs/dispersal_sampler/in_memory/packed_separable_alias/mod.rs
index a9dcb071f..47f9b5d9c 100644
--- a/necsim/impls/no-std/src/cogs/dispersal_sampler/in_memory/packed_separable_alias/mod.rs
+++ b/necsim/impls/no-std/src/cogs/dispersal_sampler/in_memory/packed_separable_alias/mod.rs
@@ -120,11 +120,11 @@ impl<M: MathsCore, H: Habitat<M>, G: RngCore<M>> InMemoryDispersalSampler<M, H,
                         end: range_from,
                     }
                 } else {
+                    // total weight already contains self-dispersal
                     let total_weight = event_weights
                         .iter()
                         .map(|(_e, w)| *w)
-                        .sum::<NonNegativeF64>()
-                        + self_dispersal_at_location;
+                        .sum::<NonNegativeF64>();
                     // Safety: Normalisation limits the result to [0.0; 1.0]
                     let self_dispersal_probability = unsafe {
                         ClosedUnitF64::new_unchecked(
diff --git a/necsim/impls/no-std/src/cogs/dispersal_sampler/in_memory/separable_alias/mod.rs b/necsim/impls/no-std/src/cogs/dispersal_sampler/in_memory/separable_alias/mod.rs
index e0493dd5b..a2228149a 100644
--- a/necsim/impls/no-std/src/cogs/dispersal_sampler/in_memory/separable_alias/mod.rs
+++ b/necsim/impls/no-std/src/cogs/dispersal_sampler/in_memory/separable_alias/mod.rs
@@ -78,6 +78,8 @@ impl<M: MathsCore, H: Habitat<M>, G: RngCore<M>> InMemoryDispersalSampler<M, H,
                     }
                 }
 
+                // total weight needs to extra include the self-dispersal,
+                //  since it was excluded from event_weights earlier
                 let total_weight = event_weights
                     .iter()
                     .map(|(_e, w)| *w)
diff --git a/necsim/impls/no-std/src/cogs/dispersal_sampler/non_spatial.rs b/necsim/impls/no-std/src/cogs/dispersal_sampler/non_spatial.rs
index 5cb7011ca..c88a80189 100644
--- a/necsim/impls/no-std/src/cogs/dispersal_sampler/non_spatial.rs
+++ b/necsim/impls/no-std/src/cogs/dispersal_sampler/non_spatial.rs
@@ -1,7 +1,7 @@
 use core::{marker::PhantomData, num::NonZeroU64};
 
 use necsim_core::{
-    cogs::{Backup, DispersalSampler, Habitat, MathsCore, RngCore, SeparableDispersalSampler},
+    cogs::{DispersalSampler, Habitat, MathsCore, RngCore, SeparableDispersalSampler},
     landscape::Location,
 };
 use necsim_core_bond::ClosedUnitF64;
@@ -9,7 +9,7 @@ use necsim_core_bond::ClosedUnitF64;
 use crate::cogs::habitat::non_spatial::NonSpatialHabitat;
 
 #[allow(clippy::module_name_repetitions)]
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 #[cfg_attr(feature = "cuda", derive(rust_cuda::lend::LendRustToCuda))]
 #[cfg_attr(feature = "cuda", cuda(free = "M", free = "G"))]
 pub struct NonSpatialDispersalSampler<M: MathsCore, G: RngCore<M>> {
@@ -25,9 +25,8 @@ impl<M: MathsCore, G: RngCore<M>> Default for NonSpatialDispersalSampler<M, G> {
     }
 }
 
-#[contract_trait]
-impl<M: MathsCore, G: RngCore<M>> Backup for NonSpatialDispersalSampler<M, G> {
-    unsafe fn backup_unchecked(&self) -> Self {
+impl<M: MathsCore, G: RngCore<M>> Clone for NonSpatialDispersalSampler<M, G> {
+    fn clone(&self) -> Self {
         Self {
             marker: PhantomData::<(M, G)>,
         }
diff --git a/necsim/impls/no-std/src/cogs/dispersal_sampler/spatially_implicit.rs b/necsim/impls/no-std/src/cogs/dispersal_sampler/spatially_implicit.rs
index 6aec8c14b..b2024f427 100644
--- a/necsim/impls/no-std/src/cogs/dispersal_sampler/spatially_implicit.rs
+++ b/necsim/impls/no-std/src/cogs/dispersal_sampler/spatially_implicit.rs
@@ -1,5 +1,5 @@
 use necsim_core::{
-    cogs::{Backup, DispersalSampler, Habitat, MathsCore, RngCore, SeparableDispersalSampler},
+    cogs::{DispersalSampler, Habitat, MathsCore, RngCore, SeparableDispersalSampler},
     landscape::Location,
 };
 use necsim_core_bond::{ClosedUnitF64, OpenClosedUnitF64 as PositiveUnitF64};
@@ -10,7 +10,7 @@ use crate::cogs::{
 };
 
 #[allow(clippy::module_name_repetitions)]
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 #[cfg_attr(feature = "cuda", derive(rust_cuda::lend::LendRustToCuda))]
 #[cfg_attr(feature = "cuda", cuda(free = "M"))]
 pub struct SpatiallyImplicitDispersalSampler<M: MathsCore, G: RngCore<M>> {
@@ -32,12 +32,11 @@ impl<M: MathsCore, G: RngCore<M>> SpatiallyImplicitDispersalSampler<M, G> {
     }
 }
 
-#[contract_trait]
-impl<M: MathsCore, G: RngCore<M>> Backup for SpatiallyImplicitDispersalSampler<M, G> {
-    unsafe fn backup_unchecked(&self) -> Self {
+impl<M: MathsCore, G: RngCore<M>> Clone for SpatiallyImplicitDispersalSampler<M, G> {
+    fn clone(&self) -> Self {
         Self {
-            local: self.local.backup_unchecked(),
-            meta: self.meta.backup_unchecked(),
+            local: self.local.clone(),
+            meta: self.meta.clone(),
             local_migration_probability_per_generation: self
                 .local_migration_probability_per_generation,
         }
diff --git a/necsim/impls/no-std/src/cogs/dispersal_sampler/wrapping_noise.rs b/necsim/impls/no-std/src/cogs/dispersal_sampler/wrapping_noise.rs
index 85aef9d41..54f83c872 100644
--- a/necsim/impls/no-std/src/cogs/dispersal_sampler/wrapping_noise.rs
+++ b/necsim/impls/no-std/src/cogs/dispersal_sampler/wrapping_noise.rs
@@ -1,8 +1,5 @@
 use necsim_core::{
-    cogs::{
-        Backup, DispersalSampler, Habitat, MathsCore, RngCore, RngSampler,
-        SeparableDispersalSampler,
-    },
+    cogs::{DispersalSampler, Habitat, MathsCore, RngCore, RngSampler, SeparableDispersalSampler},
     landscape::Location,
 };
 use necsim_core_bond::{ClosedUnitF64, NonNegativeF64};
@@ -13,7 +10,7 @@ use crate::cogs::{
 };
 
 #[allow(clippy::module_name_repetitions)]
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 #[cfg_attr(feature = "cuda", derive(rust_cuda::lend::LendRustToCuda))]
 #[cfg_attr(feature = "cuda", cuda(free = "M"))]
 pub struct WrappingNoiseApproximateNormalDispersalSampler<M: MathsCore, G: RngCore<M>> {
@@ -30,11 +27,10 @@ impl<M: MathsCore, G: RngCore<M>> WrappingNoiseApproximateNormalDispersalSampler
     }
 }
 
-#[contract_trait]
-impl<M: MathsCore, G: RngCore<M>> Backup for WrappingNoiseApproximateNormalDispersalSampler<M, G> {
-    unsafe fn backup_unchecked(&self) -> Self {
+impl<M: MathsCore, G: RngCore<M>> Clone for WrappingNoiseApproximateNormalDispersalSampler<M, G> {
+    fn clone(&self) -> Self {
         Self {
-            inner: self.inner.backup_unchecked(),
+            inner: self.inner.clone(),
         }
     }
 }
diff --git a/necsim/impls/no-std/src/cogs/habitat/almost_infinite.rs b/necsim/impls/no-std/src/cogs/habitat/almost_infinite.rs
index abd31221e..f3d97311b 100644
--- a/necsim/impls/no-std/src/cogs/habitat/almost_infinite.rs
+++ b/necsim/impls/no-std/src/cogs/habitat/almost_infinite.rs
@@ -1,7 +1,7 @@
 use core::{fmt, marker::PhantomData};
 
 use necsim_core::{
-    cogs::{Backup, Habitat, MathsCore, RngCore, UniformlySampleableHabitat},
+    cogs::{Habitat, MathsCore, RngCore, UniformlySampleableHabitat},
     landscape::{IndexedLocation, LandscapeExtent, Location},
 };
 use necsim_core_bond::{OffByOneU32, OffByOneU64};
@@ -12,7 +12,6 @@ const ALMOST_INFINITE_EXTENT: LandscapeExtent =
     LandscapeExtent::new(Location::new(0, 0), OffByOneU32::max(), OffByOneU32::max());
 
 #[allow(clippy::module_name_repetitions)]
-#[derive(Clone)]
 #[cfg_attr(feature = "cuda", derive(rust_cuda::lend::LendRustToCuda))]
 #[cfg_attr(feature = "cuda", cuda(free = "M"))]
 pub struct AlmostInfiniteHabitat<M: MathsCore> {
@@ -33,9 +32,8 @@ impl<M: MathsCore> Default for AlmostInfiniteHabitat<M> {
     }
 }
 
-#[contract_trait]
-impl<M: MathsCore> Backup for AlmostInfiniteHabitat<M> {
-    unsafe fn backup_unchecked(&self) -> Self {
+impl<M: MathsCore> Clone for AlmostInfiniteHabitat<M> {
+    fn clone(&self) -> Self {
         Self {
             marker: PhantomData::<M>,
         }
diff --git a/necsim/impls/no-std/src/cogs/habitat/in_memory.rs b/necsim/impls/no-std/src/cogs/habitat/in_memory.rs
index 031a4ff08..a5464654a 100644
--- a/necsim/impls/no-std/src/cogs/habitat/in_memory.rs
+++ b/necsim/impls/no-std/src/cogs/habitat/in_memory.rs
@@ -3,7 +3,7 @@ use core::marker::PhantomData;
 use alloc::{sync::Arc, vec::Vec};
 
 use necsim_core::{
-    cogs::{Backup, Habitat, MathsCore, RngCore, UniformlySampleableHabitat},
+    cogs::{Habitat, MathsCore, RngCore, UniformlySampleableHabitat},
     landscape::{IndexedLocation, LandscapeExtent, Location},
 };
 use necsim_core_bond::{OffByOneU32, OffByOneU64};
@@ -11,7 +11,7 @@ use necsim_core_bond::{OffByOneU32, OffByOneU64};
 use crate::array2d::Array2D;
 
 #[allow(clippy::module_name_repetitions)]
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 #[cfg_attr(feature = "cuda", derive(rust_cuda::lend::LendRustToCuda))]
 #[cfg_attr(feature = "cuda", cuda(free = "M"))]
 pub struct InMemoryHabitat<M: MathsCore> {
@@ -24,9 +24,8 @@ pub struct InMemoryHabitat<M: MathsCore> {
     marker: PhantomData<M>,
 }
 
-#[contract_trait]
-impl<M: MathsCore> Backup for InMemoryHabitat<M> {
-    unsafe fn backup_unchecked(&self) -> Self {
+impl<M: MathsCore> Clone for InMemoryHabitat<M> {
+    fn clone(&self) -> Self {
         Self {
             habitat: self.habitat.clone(),
             u64_injection: self.u64_injection.clone(),
diff --git a/necsim/impls/no-std/src/cogs/habitat/non_spatial.rs b/necsim/impls/no-std/src/cogs/habitat/non_spatial.rs
index 720e064a8..f210cba81 100644
--- a/necsim/impls/no-std/src/cogs/habitat/non_spatial.rs
+++ b/necsim/impls/no-std/src/cogs/habitat/non_spatial.rs
@@ -4,13 +4,13 @@ use core::{
 };
 
 use necsim_core::{
-    cogs::{Backup, Habitat, MathsCore, RngCore, UniformlySampleableHabitat},
+    cogs::{Habitat, MathsCore, RngCore, UniformlySampleableHabitat},
     landscape::{IndexedLocation, LandscapeExtent, Location},
 };
 use necsim_core_bond::{OffByOneU32, OffByOneU64};
 
 #[allow(clippy::module_name_repetitions)]
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 #[cfg_attr(feature = "cuda", derive(rust_cuda::lend::LendRustToCuda))]
 #[cfg_attr(feature = "cuda", cuda(free = "M"))]
 pub struct NonSpatialHabitat<M: MathsCore> {
@@ -54,9 +54,8 @@ impl<M: MathsCore> NonSpatialHabitat<M> {
     }
 }
 
-#[contract_trait]
-impl<M: MathsCore> Backup for NonSpatialHabitat<M> {
-    unsafe fn backup_unchecked(&self) -> Self {
+impl<M: MathsCore> Clone for NonSpatialHabitat<M> {
+    fn clone(&self) -> Self {
         Self {
             extent: self.extent.clone(),
             deme: self.deme,
diff --git a/necsim/impls/no-std/src/cogs/habitat/spatially_implicit.rs b/necsim/impls/no-std/src/cogs/habitat/spatially_implicit.rs
index eed0596b1..390176c2d 100644
--- a/necsim/impls/no-std/src/cogs/habitat/spatially_implicit.rs
+++ b/necsim/impls/no-std/src/cogs/habitat/spatially_implicit.rs
@@ -1,7 +1,7 @@
 use core::num::NonZeroU32;
 
 use necsim_core::{
-    cogs::{Backup, Habitat, MathsCore, RngCore, UniformlySampleableHabitat},
+    cogs::{Habitat, MathsCore, RngCore, UniformlySampleableHabitat},
     landscape::{IndexedLocation, LandscapeExtent, Location},
 };
 use necsim_core_bond::{OffByOneU32, OffByOneU64};
@@ -12,7 +12,7 @@ const SPATIALLY_IMPLICIT_EXTENT: LandscapeExtent =
     LandscapeExtent::new(Location::new(0, 0), OffByOneU32::max(), OffByOneU32::max());
 
 #[allow(clippy::module_name_repetitions)]
-#[derive(Clone, Debug)]
+#[derive(Debug)]
 #[cfg_attr(feature = "cuda", derive(rust_cuda::lend::LendRustToCuda))]
 #[cfg_attr(feature = "cuda", cuda(free = "M"))]
 pub struct SpatiallyImplicitHabitat<M: MathsCore> {
@@ -62,12 +62,11 @@ impl<M: MathsCore> SpatiallyImplicitHabitat<M> {
     }
 }
 
-#[contract_trait]
-impl<M: MathsCore> Backup for SpatiallyImplicitHabitat<M> {
-    unsafe fn backup_unchecked(&self) -> Self {
+impl<M: MathsCore> Clone for SpatiallyImplicitHabitat<M> {
+    fn clone(&self) -> Self {
         Self {
-            local: self.local.backup_unchecked(),
-            meta: self.meta.backup_unchecked(),
+            local: self.local.clone(),
+            meta: self.meta.clone(),
         }
     }
 }
diff --git a/necsim/impls/no-std/src/cogs/habitat/wrapping_noise/mod.rs b/necsim/impls/no-std/src/cogs/habitat/wrapping_noise/mod.rs
index 47a74c080..5e4f1bd3f 100644
--- a/necsim/impls/no-std/src/cogs/habitat/wrapping_noise/mod.rs
+++ b/necsim/impls/no-std/src/cogs/habitat/wrapping_noise/mod.rs
@@ -7,7 +7,7 @@ mod opensimplex_noise;
 use opensimplex_noise::OpenSimplexNoise;
 
 use necsim_core::{
-    cogs::{Backup, Habitat, MathsCore, RngCore, UniformlySampleableHabitat},
+    cogs::{Habitat, MathsCore, RngCore, UniformlySampleableHabitat},
     landscape::{IndexedLocation, LandscapeExtent, Location},
 };
 
@@ -17,7 +17,6 @@ use crate::cogs::{
 };
 
 #[allow(clippy::module_name_repetitions)]
-#[derive(Clone)]
 #[cfg_attr(feature = "cuda", derive(rust_cuda::lend::LendRustToCuda))]
 #[cfg_attr(feature = "cuda", cuda(free = "M"))]
 pub struct WrappingNoiseHabitat<M: MathsCore> {
@@ -118,11 +117,10 @@ impl<M: MathsCore> Default for WrappingNoiseHabitat<M> {
     }
 }
 
-#[contract_trait]
-impl<M: MathsCore> Backup for WrappingNoiseHabitat<M> {
-    unsafe fn backup_unchecked(&self) -> Self {
+impl<M: MathsCore> Clone for WrappingNoiseHabitat<M> {
+    fn clone(&self) -> Self {
         Self {
-            inner: self.inner.backup_unchecked(),
+            inner: self.inner.clone(),
             coverage: self.coverage,
             threshold: self.threshold,
             scale: self.scale,
diff --git a/necsim/impls/no-std/src/cogs/rng/seahash.rs b/necsim/impls/no-std/src/cogs/rng/seahash.rs
index bbfc0df7b..d13be722f 100644
--- a/necsim/impls/no-std/src/cogs/rng/seahash.rs
+++ b/necsim/impls/no-std/src/cogs/rng/seahash.rs
@@ -1,11 +1,11 @@
 use core::marker::PhantomData;
 
-use necsim_core::cogs::{Backup, MathsCore, PrimeableRng, RngCore};
+use necsim_core::cogs::{MathsCore, PrimeableRng, RngCore};
 
 use serde::{Deserialize, Serialize};
 
 #[allow(clippy::module_name_repetitions)]
-#[derive(Clone, Debug, Serialize, Deserialize, TypeLayout)]
+#[derive(Debug, Serialize, Deserialize, TypeLayout)]
 #[serde(deny_unknown_fields)]
 #[layout(free = "M")]
 pub struct SeaHash<M: MathsCore> {
@@ -17,10 +17,15 @@ pub struct SeaHash<M: MathsCore> {
     marker: PhantomData<M>,
 }
 
-#[contract_trait]
-impl<M: MathsCore> Backup for SeaHash<M> {
-    unsafe fn backup_unchecked(&self) -> Self {
-        self.clone()
+impl<M: MathsCore> Clone for SeaHash<M> {
+    fn clone(&self) -> Self {
+        Self {
+            seed: self.seed,
+            location: self.location,
+            time: self.time,
+            offset: self.offset,
+            marker: PhantomData::<M>,
+        }
     }
 }
 
diff --git a/necsim/impls/no-std/src/cogs/rng/wyhash.rs b/necsim/impls/no-std/src/cogs/rng/wyhash.rs
index dfa2d4d3e..2697546d5 100644
--- a/necsim/impls/no-std/src/cogs/rng/wyhash.rs
+++ b/necsim/impls/no-std/src/cogs/rng/wyhash.rs
@@ -1,6 +1,6 @@
 use core::marker::PhantomData;
 
-use necsim_core::cogs::{Backup, MathsCore, PrimeableRng, RngCore};
+use necsim_core::cogs::{MathsCore, PrimeableRng, RngCore};
 
 use serde::{Deserialize, Serialize};
 
@@ -12,7 +12,7 @@ const P2: u64 = 0x8ebc_6af0_9c88_c6e3;
 const P5: u64 = 0xeb44_acca_b455_d165;
 
 #[allow(clippy::module_name_repetitions)]
-#[derive(Clone, Debug, Serialize, Deserialize, TypeLayout)]
+#[derive(Debug, Serialize, Deserialize, TypeLayout)]
 #[layout(free = "M")]
 #[serde(deny_unknown_fields)]
 #[repr(C)]
@@ -23,10 +23,13 @@ pub struct WyHash<M: MathsCore> {
     marker: PhantomData<M>,
 }
 
-#[contract_trait]
-impl<M: MathsCore> Backup for WyHash<M> {
-    unsafe fn backup_unchecked(&self) -> Self {
-        self.clone()
+impl<M: MathsCore> Clone for WyHash<M> {
+    fn clone(&self) -> Self {
+        Self {
+            seed: self.seed,
+            state: self.state,
+            marker: PhantomData::<M>,
+        }
     }
 }
 
diff --git a/necsim/impls/no-std/src/cogs/speciation_probability/spatially_implicit.rs b/necsim/impls/no-std/src/cogs/speciation_probability/spatially_implicit.rs
index 90c064bb7..2321250b9 100644
--- a/necsim/impls/no-std/src/cogs/speciation_probability/spatially_implicit.rs
+++ b/necsim/impls/no-std/src/cogs/speciation_probability/spatially_implicit.rs
@@ -1,5 +1,5 @@
 use necsim_core::{
-    cogs::{Backup, Habitat, MathsCore, SpeciationProbability},
+    cogs::{Habitat, MathsCore, SpeciationProbability},
     landscape::Location,
 };
 use necsim_core_bond::{ClosedUnitF64, OpenClosedUnitF64 as PositiveUnitF64};
@@ -22,15 +22,6 @@ impl SpatiallyImplicitSpeciationProbability {
     }
 }
 
-#[contract_trait]
-impl Backup for SpatiallyImplicitSpeciationProbability {
-    unsafe fn backup_unchecked(&self) -> Self {
-        Self {
-            meta_speciation_probability: self.meta_speciation_probability,
-        }
-    }
-}
-
 #[contract_trait]
 impl<M: MathsCore> SpeciationProbability<M, SpatiallyImplicitHabitat<M>>
     for SpatiallyImplicitSpeciationProbability
diff --git a/necsim/impls/no-std/src/cogs/speciation_probability/uniform.rs b/necsim/impls/no-std/src/cogs/speciation_probability/uniform.rs
index 6e071ce3f..9c119db94 100644
--- a/necsim/impls/no-std/src/cogs/speciation_probability/uniform.rs
+++ b/necsim/impls/no-std/src/cogs/speciation_probability/uniform.rs
@@ -1,5 +1,5 @@
 use necsim_core::{
-    cogs::{Backup, Habitat, MathsCore, SpeciationProbability},
+    cogs::{Habitat, MathsCore, SpeciationProbability},
     landscape::Location,
 };
 use necsim_core_bond::ClosedUnitF64;
@@ -20,15 +20,6 @@ impl UniformSpeciationProbability {
     }
 }
 
-#[contract_trait]
-impl Backup for UniformSpeciationProbability {
-    unsafe fn backup_unchecked(&self) -> Self {
-        Self {
-            speciation_probability: self.speciation_probability,
-        }
-    }
-}
-
 #[contract_trait]
 impl<M: MathsCore, H: Habitat<M>> SpeciationProbability<M, H> for UniformSpeciationProbability {
     #[must_use]
diff --git a/necsim/impls/no-std/src/cogs/turnover_rate/uniform.rs b/necsim/impls/no-std/src/cogs/turnover_rate/uniform.rs
index 671111023..c2465befc 100644
--- a/necsim/impls/no-std/src/cogs/turnover_rate/uniform.rs
+++ b/necsim/impls/no-std/src/cogs/turnover_rate/uniform.rs
@@ -1,5 +1,5 @@
 use necsim_core::{
-    cogs::{Backup, Habitat, MathsCore, TurnoverRate},
+    cogs::{Habitat, MathsCore, TurnoverRate},
     landscape::Location,
 };
 use necsim_core_bond::{NonNegativeF64, PositiveF64};
@@ -19,15 +19,6 @@ impl Default for UniformTurnoverRate {
     }
 }
 
-#[contract_trait]
-impl Backup for UniformTurnoverRate {
-    unsafe fn backup_unchecked(&self) -> Self {
-        Self {
-            turnover_rate: self.turnover_rate,
-        }
-    }
-}
-
 #[contract_trait]
 impl<M: MathsCore, H: Habitat<M>> TurnoverRate<M, H> for UniformTurnoverRate {
     #[must_use]
diff --git a/necsim/partitioning/core/src/lib.rs b/necsim/partitioning/core/src/lib.rs
index ccf8d5746..f4a719a14 100644
--- a/necsim/partitioning/core/src/lib.rs
+++ b/necsim/partitioning/core/src/lib.rs
@@ -66,8 +66,6 @@ pub trait LocalPartition<'p, R: Reporter>: Sized {
 
     fn get_reporter(&mut self) -> &mut Self::Reporter;
 
-    fn is_root(&self) -> bool;
-
     fn get_partition(&self) -> Partition;
 
     fn migrate_individuals<'a, E: Iterator<Item = (u32, MigratingLineage)>>(
diff --git a/necsim/partitioning/monolithic/src/lib.rs b/necsim/partitioning/monolithic/src/lib.rs
index 6975454b6..b1e255670 100644
--- a/necsim/partitioning/monolithic/src/lib.rs
+++ b/necsim/partitioning/monolithic/src/lib.rs
@@ -107,13 +107,6 @@ impl<'p, R: Reporter> LocalPartition<'p, R> for MonolithicLocalPartition<R> {
         self
     }
 
-    fn is_root(&self) -> bool {
-        match self {
-            Self::Live(partition) => partition.is_root(),
-            Self::Recorded(partition) => partition.is_root(),
-        }
-    }
-
     fn get_partition(&self) -> Partition {
         match self {
             Self::Live(partition) => partition.get_partition(),
diff --git a/necsim/partitioning/monolithic/src/live.rs b/necsim/partitioning/monolithic/src/live.rs
index 023087357..8b839e690 100644
--- a/necsim/partitioning/monolithic/src/live.rs
+++ b/necsim/partitioning/monolithic/src/live.rs
@@ -44,10 +44,6 @@ impl<'p, R: Reporter> LocalPartition<'p, R> for LiveMonolithicLocalPartition<R>
         &mut self.reporter
     }
 
-    fn is_root(&self) -> bool {
-        true
-    }
-
     fn get_partition(&self) -> Partition {
         Partition::monolithic()
     }
diff --git a/necsim/partitioning/monolithic/src/recorded.rs b/necsim/partitioning/monolithic/src/recorded.rs
index dfd0c2ded..fae4c9d6c 100644
--- a/necsim/partitioning/monolithic/src/recorded.rs
+++ b/necsim/partitioning/monolithic/src/recorded.rs
@@ -54,10 +54,6 @@ impl<'p, R: Reporter> LocalPartition<'p, R> for RecordedMonolithicLocalPartition
         self
     }
 
-    fn is_root(&self) -> bool {
-        true
-    }
-
     fn get_partition(&self) -> Partition {
         Partition::monolithic()
     }
diff --git a/necsim/partitioning/mpi/src/lib.rs b/necsim/partitioning/mpi/src/lib.rs
index dba2c1980..0ba058d3c 100644
--- a/necsim/partitioning/mpi/src/lib.rs
+++ b/necsim/partitioning/mpi/src/lib.rs
@@ -294,21 +294,30 @@ fn reduce_partitioning_data<T: serde::Serialize + serde::de::DeserializeOwned>(
     data: T,
     fold: fn(T, T) -> T,
 ) -> anyhow::Result<T> {
-    let local_ser = postcard::to_stdvec(&data).context("MPI data failed to serialize")?;
+    let local_ser =
+        postcard::to_stdvec(&data).context("MPI local partition result failed to serialize")?;
     std::mem::drop(data);
+    let local_ser_len = Count::try_from(local_ser.len())
+        .context("MPI local partition result is too big to share")?;
 
     #[allow(clippy::cast_sign_loss)]
     let mut counts = vec![0 as Count; world.size() as usize];
-    world.all_gather_into(&(Count::try_from(local_ser.len()).unwrap()), &mut counts);
+    world.all_gather_into(&local_ser_len, &mut counts);
 
     let offsets = counts
         .iter()
         .scan(0 as Count, |acc, &x| {
             let tmp = *acc;
-            *acc = (*acc).checked_add(x).unwrap();
-            Some(tmp)
+            if let Some(a) = (*acc).checked_add(x) {
+                *acc = a;
+            } else {
+                return Some(Err(anyhow::anyhow!(
+                    "MPI all local partition results combined are too big to share"
+                )));
+            }
+            Some(Ok(tmp))
         })
-        .collect::<Vec<_>>();
+        .collect::<Result<Vec<_>, _>>()?;
 
     #[allow(clippy::cast_sign_loss)]
     let mut all_sers = vec![0_u8; counts.iter().copied().sum::<Count>() as usize];
diff --git a/necsim/partitioning/mpi/src/partition/common.rs b/necsim/partitioning/mpi/src/partition/common.rs
index 6c274d73e..de67dc7b2 100644
--- a/necsim/partitioning/mpi/src/partition/common.rs
+++ b/necsim/partitioning/mpi/src/partition/common.rs
@@ -208,7 +208,7 @@ impl<'p> MpiCommonPartition<'p> {
             }
         }
 
-        ImmigrantPopIterator::new(&mut self.migration_buffers[self.get_partition().rank() as usize])
+        ImmigrantPopIterator::new(&mut self.migration_buffers[self_rank_index])
     }
 
     #[must_use]
diff --git a/necsim/partitioning/mpi/src/partition/mod.rs b/necsim/partitioning/mpi/src/partition/mod.rs
index 6d584f236..d77255107 100644
--- a/necsim/partitioning/mpi/src/partition/mod.rs
+++ b/necsim/partitioning/mpi/src/partition/mod.rs
@@ -38,13 +38,6 @@ impl<'p, R: Reporter> LocalPartition<'p, R> for MpiLocalPartition<'p, R> {
         self
     }
 
-    fn is_root(&self) -> bool {
-        match self {
-            Self::Root(partition) => partition.is_root(),
-            Self::Parallel(partition) => partition.is_root(),
-        }
-    }
-
     fn get_partition(&self) -> Partition {
         match self {
             Self::Root(partition) => partition.get_partition(),
diff --git a/necsim/partitioning/mpi/src/partition/parallel.rs b/necsim/partitioning/mpi/src/partition/parallel.rs
index dfb5775d2..85b41d576 100644
--- a/necsim/partitioning/mpi/src/partition/parallel.rs
+++ b/necsim/partitioning/mpi/src/partition/parallel.rs
@@ -91,10 +91,6 @@ impl<'p, R: Reporter> LocalPartition<'p, R> for MpiParallelPartition<'p, R> {
         self
     }
 
-    fn is_root(&self) -> bool {
-        false
-    }
-
     fn get_partition(&self) -> Partition {
         self.common.get_partition()
     }
diff --git a/necsim/partitioning/mpi/src/partition/root.rs b/necsim/partitioning/mpi/src/partition/root.rs
index ca6dd68e2..2cdd8c467 100644
--- a/necsim/partitioning/mpi/src/partition/root.rs
+++ b/necsim/partitioning/mpi/src/partition/root.rs
@@ -108,10 +108,6 @@ impl<'p, R: Reporter> LocalPartition<'p, R> for MpiRootPartition<'p, R> {
         self
     }
 
-    fn is_root(&self) -> bool {
-        true
-    }
-
     fn get_partition(&self) -> Partition {
         self.common.get_partition()
     }
diff --git a/necsim/partitioning/threads/src/lib.rs b/necsim/partitioning/threads/src/lib.rs
index 54ac2b7c5..540b1f9bb 100644
--- a/necsim/partitioning/threads/src/lib.rs
+++ b/necsim/partitioning/threads/src/lib.rs
@@ -50,7 +50,7 @@ pub enum ThreadsLocalPartitionError {
 }
 
 pub struct ThreadsPartitioning {
-    size: PartitionSize,
+    num_threads: PartitionSize,
     migration_interval: Duration,
     progress_interval: Duration,
 }
@@ -66,7 +66,7 @@ impl fmt::Debug for ThreadsPartitioning {
         }
 
         fmt.debug_struct(stringify!(ThreadsPartitioning))
-            .field("size", &self.get_size().get())
+            .field("num_threads", &self.num_threads.get())
             .field(
                 "migration_interval",
                 &FormattedDuration(self.migration_interval),
@@ -82,7 +82,7 @@ impl fmt::Debug for ThreadsPartitioning {
 impl Serialize for ThreadsPartitioning {
     fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
         let mut args = serializer.serialize_struct(stringify!(ThreadsPartitioning), 3)?;
-        args.serialize_field("size", &self.get_size())?;
+        args.serialize_field("threads", &self.num_threads)?;
         args.serialize_field(
             "migration",
             &format_duration(self.migration_interval).to_string(),
@@ -100,7 +100,7 @@ impl<'de> Deserialize<'de> for ThreadsPartitioning {
         let raw = ThreadsPartitioningRaw::deserialize(deserializer)?;
 
         Ok(Self {
-            size: raw.num_threads,
+            num_threads: raw.num_threads,
             migration_interval: raw.migration_interval,
             progress_interval: raw.progress_interval,
         })
@@ -126,9 +126,10 @@ impl Partitioning for ThreadsPartitioning {
     type LocalPartition<'p, R: Reporter> = ThreadsLocalPartition<'p, R>;
 
     fn get_size(&self) -> PartitionSize {
-        self.size
+        self.num_threads
     }
 
+    #[allow(clippy::too_many_lines)]
     /// # Errors
     ///
     /// Returns `MissingEventLog` if the local partition is non-monolithic and
@@ -154,27 +155,28 @@ impl Partitioning for ThreadsPartitioning {
 
         let mut progress_reporter: FilteredReporter<R, False, False, True> =
             reporter_context.try_build()?;
-        let (progress_sender, progress_receiver) = sync_channel(self.size.get() as usize);
+        let (progress_sender, progress_receiver) = sync_channel(self.num_threads.get() as usize);
         let progress_channels = self
-            .size
+            .num_threads
             .partitions()
             .map(|_| progress_sender.clone())
             .collect::<Vec<_>>();
         std::mem::drop(progress_sender);
 
-        let vote_any = Vote::new(self.size.get() as usize);
-        let vote_min_time = Vote::new_with_dummy(self.size.get() as usize, (PositiveF64::one(), 0));
+        let vote_any = Vote::new(self.num_threads.get() as usize);
+        let vote_min_time =
+            Vote::new_with_dummy(self.num_threads.get() as usize, (PositiveF64::one(), 0));
         let vote_termination =
-            AsyncVote::new_with_dummy(self.size.get() as usize, ControlFlow::Continue(()));
+            AsyncVote::new_with_dummy(self.num_threads.get() as usize, ControlFlow::Continue(()));
 
         let (emigration_channels, immigration_channels): (Vec<_>, Vec<_>) = self
-            .size
+            .num_threads
             .partitions()
-            .map(|_| sync_channel(self.size.get() as usize))
+            .map(|_| sync_channel(self.num_threads.get() as usize))
             .unzip();
 
         let event_logs = self
-            .size
+            .num_threads
             .partitions()
             .map(|partition| {
                 let mut directory = event_log.directory().to_owned();
@@ -187,9 +189,9 @@ impl Partitioning for ThreadsPartitioning {
             })
             .collect::<Result<Vec<_>, _>>()?;
 
-        let sync_barrier = Arc::new(Barrier::new(self.size.get() as usize));
+        let sync_barrier = Arc::new(Barrier::new(self.num_threads.get() as usize));
         let args = self
-            .size
+            .num_threads
             .partitions()
             .map(|_| args.clone())
             .collect::<Vec<_>>();
@@ -202,7 +204,7 @@ impl Partitioning for ThreadsPartitioning {
             let sync_barrier = &sync_barrier;
 
             let thread_handles = self
-                .size
+                .num_threads
                 .partitions()
                 .zip(immigration_channels)
                 .zip(event_logs)
@@ -231,7 +233,8 @@ impl Partitioning for ThreadsPartitioning {
                 )
                 .collect::<Vec<_>>();
 
-            let mut progress_remaining = vec![0; self.size.get() as usize].into_boxed_slice();
+            let mut progress_remaining =
+                vec![0; self.num_threads.get() as usize].into_boxed_slice();
             for (remaining, rank) in progress_receiver {
                 progress_remaining[rank as usize] = remaining;
                 progress_reporter.report_progress(
diff --git a/necsim/partitioning/threads/src/partition.rs b/necsim/partitioning/threads/src/partition.rs
index 7b0221b94..bf511a1ba 100644
--- a/necsim/partitioning/threads/src/partition.rs
+++ b/necsim/partitioning/threads/src/partition.rs
@@ -115,10 +115,6 @@ impl<'p, R: Reporter> LocalPartition<'p, R> for ThreadsLocalPartition<'p, R> {
         self
     }
 
-    fn is_root(&self) -> bool {
-        true
-    }
-
     fn get_partition(&self) -> Partition {
         self.partition
     }
@@ -255,7 +251,13 @@ impl<'p, R: Reporter> LocalPartition<'p, R> for ThreadsLocalPartition<'p, R> {
         );
 
         match async_vote {
-            Poll::Pending => ControlFlow::Continue(()),
+            Poll::Pending => {
+                // This partition doesn't have any work right now but we have
+                //  to do another round of voting, so let's yield to not busy
+                //  wait - we'll be woken up if more work comes in
+                std::thread::yield_now();
+                ControlFlow::Continue(())
+            },
             Poll::Ready(result) => result,
         }
     }
diff --git a/rustcoalescence/src/cli/simulate/dispatch/valid/info.rs b/rustcoalescence/src/cli/simulate/dispatch/valid/info.rs
index a815fe02d..759a3bf09 100644
--- a/rustcoalescence/src/cli/simulate/dispatch/valid/info.rs
+++ b/rustcoalescence/src/cli/simulate/dispatch/valid/info.rs
@@ -120,12 +120,12 @@ where
     }
 
     let result = launch::simulate::<M, G, A, O, R, P>(
-        algorithm_args,
+        &mut local_partition,
+        sample,
         rng,
         scenario,
-        sample,
+        algorithm_args,
         pause_before,
-        &mut local_partition,
     )?;
 
     if log::log_enabled!(log::Level::Info) {
diff --git a/rustcoalescence/src/cli/simulate/dispatch/valid/launch.rs b/rustcoalescence/src/cli/simulate/dispatch/valid/launch.rs
index a3982a0db..8b1978ee3 100644
--- a/rustcoalescence/src/cli/simulate/dispatch/valid/launch.rs
+++ b/rustcoalescence/src/cli/simulate/dispatch/valid/launch.rs
@@ -23,12 +23,13 @@ pub(super) fn simulate<
     R: Reporter,
     P: LocalPartition<'p, R>,
 >(
-    algorithm_args: A::Arguments,
+    local_partition: &mut P,
+
+    sample: Sample,
     rng: G,
     scenario: ScenarioCogs<M, G, O>,
-    sample: Sample,
+    algorithm_args: A::Arguments,
     pause_before: Option<NonNegativeF64>,
-    local_partition: &mut P,
 ) -> anyhow::Result<SimulationOutcome<M, G>> {
     let lineages = match sample.origin {
         SampleOrigin::Habitat => {