diff --git a/include/faabric/loadbalance/LoadBalancePolicy.h b/include/faabric/loadbalance/LoadBalancePolicy.h
index 75da1aebb..ac618787a 100644
--- a/include/faabric/loadbalance/LoadBalancePolicy.h
+++ b/include/faabric/loadbalance/LoadBalancePolicy.h
@@ -8,23 +8,23 @@
 class LoadBalancePolicy
 {
     public:
-        virtual std::vector<std::string> dispatch(const std::set<std::string>& warm_faaslets, int number_of_messages, faabric::scheduler::Scheduler& scheduler) = 0;
+        virtual std::vector<std::string> dispatch(const std::set<std::string>& warm_faaslets, int number_of_messages, const faabric::scheduler::Scheduler& scheduler) = 0;
 };
 
 class FaasmDefaultPolicy : public LoadBalancePolicy
 {
     public:
-        std::vector<std::string> dispatch(const std::set<std::string>& warm_faaslets, int number_of_messages, faabric::scheduler::Scheduler& scheduler) override;
+        std::vector<std::string> dispatch(const std::set<std::string>& warm_faaslets, int number_of_messages, const faabric::scheduler::Scheduler& scheduler) override;
 };
 
 class LeastLoadAveragePolicy : public LoadBalancePolicy
 {
     public:
-        std::vector<std::string> dispatch(const std::set<std::string>& warm_faaslets, int number_of_messages, faabric::scheduler::Scheduler& scheduler) override;
+        std::vector<std::string> dispatch(const std::set<std::string>& warm_faaslets, int number_of_messages, const faabric::scheduler::Scheduler& scheduler) override;
 };
 
 class MostSlotsPolicy : public LoadBalancePolicy
 {
     public:
-        std::vector<std::string> dispatch(const std::set<std::string>& warm_faaslets, int number_of_messages, faabric::scheduler::Scheduler& scheduler) override;
+        std::vector<std::string> dispatch(const std::set<std::string>& warm_faaslets, int number_of_messages, const faabric::scheduler::Scheduler& scheduler) override;
 };
\ No newline at end of file
diff --git a/src/loadbalance/FaasmDefaultPolicy.cpp b/src/loadbalance/FaasmDefaultPolicy.cpp
index 562aca51e..7663eb5dd 100644
--- a/src/loadbalance/FaasmDefaultPolicy.cpp
+++ b/src/loadbalance/FaasmDefaultPolicy.cpp
@@ -1,7 +1,7 @@
 #include <faabric/loadbalance/LoadBalancePolicy.h>
 #include <stdexcept>
 
-std::vector<std::string> FaasmDefaultPolicy::dispatch(const std::set<std::string>& warm_faaslets, int number_of_messages, faabric::scheduler::Scheduler& scheduler)
+std::vector<std::string> FaasmDefaultPolicy::dispatch(const std::set<std::string>& warm_faaslets, int number_of_messages, const faabric::scheduler::Scheduler& scheduler)
 {
     std::vector<std::string> hosts_delta;
     hosts_delta.reserve(number_of_messages);
diff --git a/src/loadbalance/LeastLoadAveragePolicy.cpp b/src/loadbalance/LeastLoadAveragePolicy.cpp
index c1aa8ed39..ac43784e2 100644
--- a/src/loadbalance/LeastLoadAveragePolicy.cpp
+++ b/src/loadbalance/LeastLoadAveragePolicy.cpp
@@ -1,7 +1,7 @@
 #include <faabric/loadbalance/LoadBalancePolicy.h>
 #include <stdexcept>
 
-std::vector<std::string> LeastLoadAveragePolicy::dispatch(const std::set<std::string>& warm_faaslets, int number_of_messages, faabric::scheduler::Scheduler& scheduler)
+std::vector<std::string> LeastLoadAveragePolicy::dispatch(const std::set<std::string>& warm_faaslets, int number_of_messages, const faabric::scheduler::Scheduler& scheduler)
 {
     throw std::runtime_error("LeastLoadAveragePolicy::dispatch not implemented");
 }
\ No newline at end of file
diff --git a/src/loadbalance/MostSlotsPolicy.cpp b/src/loadbalance/MostSlotsPolicy.cpp
index f1814ef39..0ebc5f2a8 100644
--- a/src/loadbalance/MostSlotsPolicy.cpp
+++ b/src/loadbalance/MostSlotsPolicy.cpp
@@ -1,7 +1,7 @@
 #include <faabric/loadbalance/LoadBalancePolicy.h>
 #include <stdexcept>
 
-std::vector<std::string> MostSlotsPolicy::dispatch(const std::set<std::string>& warm_faaslets, int number_of_messages, faabric::scheduler::Scheduler& scheduler)
+std::vector<std::string> MostSlotsPolicy::dispatch(const std::set<std::string>& warm_faaslets, int number_of_messages, const faabric::scheduler::Scheduler& scheduler)
 {
     throw std::runtime_error("MostSlotsPolicy::dispatch not implemented");
 }
\ No newline at end of file
diff --git a/src/scheduler/Scheduler.cpp b/src/scheduler/Scheduler.cpp
index 07f98780e..a250c3ef0 100644
--- a/src/scheduler/Scheduler.cpp
+++ b/src/scheduler/Scheduler.cpp
@@ -554,7 +554,7 @@ faabric::util::SchedulingDecision Scheduler::doSchedulingDecision(
             
             FaasmDefaultPolicy policy;
             const std::set<std::string>& thisRegisteredHosts = getFunctionRegisteredHosts(firstMsg.user(), firstMsg.function(), false);
-            std::vector<std::string> balanced_order = policy.dispatch(thisRegisteredHosts, remainder, this); // Messy DI to get access to methods
+            std::vector<std::string> balanced_order = policy.dispatch(thisRegisteredHosts, remainder, *this); // Messy DI to get access to methods
 
             remainder -= balanced_order.size();
             for (const auto& h : balanced_order) {