diff --git a/include/sirit/sirit.h b/include/sirit/sirit.h
index ee3a024..c729595 100644
--- a/include/sirit/sirit.h
+++ b/include/sirit/sirit.h
@@ -27,7 +27,7 @@ using Id = const Op*;
 
 class Module {
   public:
-    explicit Module();
+    explicit Module(std::uint32_t version = spv::Version);
     ~Module();
 
     /**
@@ -238,6 +238,11 @@ class Module {
     /// Make an intermediate object whose value is undefined.
     Id OpUndef(Id result_type);
 
+    // Logical
+
+    /// Result is true if Operand is false. Result is false if Operand is true.
+    Id OpLogicalNot(Id result_type, Id operand);
+
   private:
     Id AddCode(std::unique_ptr<Op> op);
 
@@ -247,6 +252,8 @@ class Module {
 
     Id AddAnnotation(std::unique_ptr<Op> op);
 
+    const std::uint32_t version;
+
     std::uint32_t bound{1};
 
     std::set<spv::Capability> capabilities;
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 3f3ff24..b48292f 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -20,6 +20,7 @@ add_library(sirit
     insts/memory.cpp
     insts/annotation.cpp
     insts/misc.cpp
+    insts/logical.cpp
 )
 target_include_directories(sirit
                            PUBLIC ../include
diff --git a/src/sirit.cpp b/src/sirit.cpp
index fd90205..56b25b8 100644
--- a/src/sirit.cpp
+++ b/src/sirit.cpp
@@ -26,7 +26,7 @@ template <typename T> static void WriteSet(Stream& stream, const T& set) {
     }
 }
 
-Module::Module() {}
+Module::Module(u32 version) : version(version) {}
 
 Module::~Module() = default;
 
@@ -35,7 +35,7 @@ std::vector<u8> Module::Assemble() const {
     Stream stream{bytes};
 
     stream.Write(spv::MagicNumber);
-    stream.Write(spv::Version);
+    stream.Write(version);
     stream.Write(GENERATOR_MAGIC_NUMBER);
     stream.Write(bound);
     stream.Write(static_cast<u32>(0));