diff --git a/day07.cpp b/day07.cpp
index 65ee93c..59e39a4 100644
--- a/day07.cpp
+++ b/day07.cpp
@@ -24,7 +24,7 @@ auto Feed(R &&amps, ValueType start) -> std::optional<ValueType> {
   for (auto &m : amps) {
     auto e = Step(m);
     if (auto i = std::get_if<Input>(&e)) {
-      i->pos = start;
+      i->input = start;
       start = StepOutput(m);
     } else {
       return {};
diff --git a/day23.cpp b/day23.cpp
index 0dbc6fa..a1f7eb5 100644
--- a/day23.cpp
+++ b/day23.cpp
@@ -19,7 +19,7 @@ using Ethernet = std::deque<Packet>;
 
 auto BuildNetwork(Machine m) -> std::vector<Machine> {
   std::vector<Machine> machines;
-  auto& i = std::get<Input>(Step(m)).pos;
+  auto& i = std::get<Input>(Step(m)).input;
   for (i = 0; i < 50; i++) {
     machines.push_back(m);
   }
@@ -32,7 +32,7 @@ auto Interact(Ethernet & ethernet, Machine & m, std::optional<Payload> p) -> voi
     switch (e.index()) {
       default: throw std::runtime_error{"unexpected halt"};
       case 0: {
-        auto& i = std::get<0>(e).pos;
+        auto& i = std::get<0>(e).input;
         if (p) {
           i = p->x;
           StepInput(m, p->y);
@@ -43,7 +43,7 @@ auto Interact(Ethernet & ethernet, Machine & m, std::optional<Payload> p) -> voi
         return;
       }
       case 1: {
-        auto d = std::get<1>(e).val;
+        auto d = std::get<1>(e).output;
         auto x = StepOutput(m);
         auto y = StepOutput(m);
         ethernet.push_back({d, {x,y}});
diff --git a/lib/include/intcode/Interpreter.hpp b/lib/include/intcode/Interpreter.hpp
index 2fe2fdd..d786e1c 100644
--- a/lib/include/intcode/Interpreter.hpp
+++ b/lib/include/intcode/Interpreter.hpp
@@ -9,11 +9,11 @@
 namespace intcode {
 
 struct Input {
-ValueType &pos;
+ValueType &input;
 };
 
 struct Output {
-ValueType val;
+ValueType output;
 };
 
 struct Halt {};
@@ -32,8 +32,8 @@ template <std::invocable<ValueType&> Fin, std::invocable<ValueType> Fout, std::i
 auto Advance(Machine & machine, Fin input, Fout output, Fhalt halt) {
   return std::visit(overloaded{
     [&](Halt) { return halt(); },
-    [&](Input i) { return input(i.pos); },
-    [&](Output o) { return output(o.val); },
+    [&](Input i) { return input(i.input); },
+    [&](Output o) { return output(o.output); },
     }, Step(machine));
 }
 
diff --git a/lib/src/Interpreter.cpp b/lib/src/Interpreter.cpp
index 41abde5..85ce251 100644
--- a/lib/src/Interpreter.cpp
+++ b/lib/src/Interpreter.cpp
@@ -6,11 +6,11 @@ BadInstruction::BadInstruction(char const* what)
     : std::runtime_error{what} {}
 
 auto StepInput(Machine & m, ValueType input) -> void {
-  std::get<Input>(Step(m)).pos = input;
+  std::get<Input>(Step(m)).input = input;
 }
 
 auto StepOutput(Machine & m) -> ValueType {
-  return std::get<Output>(Step(m)).val;
+  return std::get<Output>(Step(m)).output;
 }
 
 auto Step(Machine & m) -> std::variant<Input, Output, Halt> {