diff --git a/src/include/gridfire/engine/procedures/construction.h b/src/include/gridfire/engine/procedures/construction.h
index 3f267122..e14c98f5 100644
--- a/src/include/gridfire/engine/procedures/construction.h
+++ b/src/include/gridfire/engine/procedures/construction.h
@@ -105,7 +105,7 @@ namespace gridfire {
      */
     reaction::ReactionSet build_nuclear_network(
         const fourdst::composition::Composition &composition,
-        const std::optional<rates::weak::WeakRateInterpolator> &weakInterpolator,
+        const rates::weak::WeakRateInterpolator &weakInterpolator,
         BuildDepthType maxLayers = NetworkBuildDepth::Full,
         NetworkConstructionFlags ReactionTypes = NetworkConstructionFlags::DEFAULT
     );
diff --git a/src/lib/engine/procedures/construction.cpp b/src/lib/engine/procedures/construction.cpp
index a46cf969..8584e344 100644
--- a/src/lib/engine/procedures/construction.cpp
+++ b/src/lib/engine/procedures/construction.cpp
@@ -40,16 +40,15 @@ namespace {
 
 
     gridfire::reaction::ReactionSet register_weak_reactions(
-        const std::optional<gridfire::rates::weak::WeakRateInterpolator> &weakInterpolator,
+        const gridfire::rates::weak::WeakRateInterpolator &weakInterpolator,
         const gridfire::NetworkConstructionFlags reactionTypes
     ) {
         gridfire::reaction::ReactionSet weak_reaction_pool;
-        assert(weakInterpolator.has_value());
         if (!has_flag(reactionTypes, gridfire::NetworkConstructionFlags::WEAK)) {
             return weak_reaction_pool;
         }
 
-        for (const auto& parent_species: weakInterpolator->available_isotopes()) {
+        for (const auto& parent_species: weakInterpolator.available_isotopes()) {
             std::expected<fourdst::atomic::Species, fourdst::atomic::SpeciesErrorType> upProduct = fourdst::atomic::az_to_species(
                 parent_species.a(),
                 parent_species.z() + 1
@@ -64,7 +63,7 @@ namespace {
                         std::make_unique<gridfire::rates::weak::WeakReaction>(
                             parent_species,
                             gridfire::rates::weak::WeakReactionType::BETA_PLUS_DECAY,
-                            *weakInterpolator
+                            weakInterpolator
                         )
                     );
                 }
@@ -73,7 +72,7 @@ namespace {
                         std::make_unique<gridfire::rates::weak::WeakReaction>(
                             parent_species,
                             gridfire::rates::weak::WeakReactionType::ELECTRON_CAPTURE,
-                            *weakInterpolator
+                            weakInterpolator
                         )
                     );
                 }
@@ -84,7 +83,7 @@ namespace {
                         std::make_unique<gridfire::rates::weak::WeakReaction>(
                             parent_species,
                             gridfire::rates::weak::WeakReactionType::BETA_MINUS_DECAY,
-                            *weakInterpolator
+                            weakInterpolator
                         )
                     );
                 }
@@ -93,7 +92,7 @@ namespace {
                         std::make_unique<gridfire::rates::weak::WeakReaction>(
                             parent_species,
                             gridfire::rates::weak::WeakReactionType::POSITRON_CAPTURE,
-                            *weakInterpolator
+                            weakInterpolator
                         )
                     );
                 }
@@ -127,7 +126,7 @@ namespace gridfire {
 
     ReactionSet build_nuclear_network(
         const Composition& composition,
-        const std::optional<rates::weak::WeakRateInterpolator> &weakInterpolator,
+        const rates::weak::WeakRateInterpolator &weakInterpolator,
         BuildDepthType maxLayers,
         NetworkConstructionFlags ReactionTypes
     ) {
diff --git a/src/lib/engine/views/engine_priming.cpp b/src/lib/engine/views/engine_priming.cpp
index c47b5fd7..ac908487 100644
--- a/src/lib/engine/views/engine_priming.cpp
+++ b/src/lib/engine/views/engine_priming.cpp
@@ -55,9 +55,10 @@ namespace gridfire {
             }
         }
         if (primeReactions.empty()) {
-            LOG_ERROR(m_logger, "No priming reactions found for species '{}'.", primingSpecies.name());
-            m_logger->flush_log();
-            throw std::runtime_error("No priming reactions found for species '" + std::string(primingSpecies.name()) + "'.");
+            LOG_INFO(m_logger, "No priming reactions found for species '{}', returning empty peName set.", primingSpecies.name());
+            return std::vector<std::string>{};
+            // m_logger->flush_log();
+            // throw std::runtime_error("No priming reactions found for species '" + std::string(primingSpecies.name()) + "'.");
         }
         std::vector<std::string> primingReactionSet(primeReactions.begin(), primeReactions.end());
         // LOG_INFO(m_logger, "Constructed priming reaction set with {} reactions for species '{}'.", primingReactionSet.size(), primingSpecies.name());