diff --git a/main.cc b/main.cc
index 54ca28e..11e35fe 100644
--- a/main.cc
+++ b/main.cc
@@ -175,10 +175,10 @@ void T_Main::makeUI( )
 	ImGui::SetNextWindowPos( ImVec2( ) , ImGuiSetCond_Once );
 	ImGui::Begin( "Tools" );
 
-	ImGui::Checkbox( "Demo controls" , &demoCtrl_ );
-	ImGui::Checkbox( "Profiler" , &Globals::Profiler( ).uiEnabled( ) );
-	ImGui::Checkbox( "Output debugger" ,
-			&Globals::ODbg( ).uiEnabled( ) );
+	ImGui::Checkbox( "Demo controls" ,	&demoCtrl_ );
+	ImGui::Checkbox( "Profiler" ,		&Globals::Profiler( ).uiEnabled( ) );
+	ImGui::Checkbox( "Output debugger" ,	&Globals::ODbg( ).uiEnabled( ) );
+	ImGui::Checkbox( "Shaders" ,		&Globals::Shaders( ).uiEnabled( ) );
 
 	ImGui::End( );
 
@@ -188,6 +188,7 @@ void T_Main::makeUI( )
 
 	Globals::Profiler( ).makeUI( );
 	Globals::ODbg( ).makeUI( );
+	Globals::Shaders( ).makeUI( );
 }
 
 void T_Main::render( )
diff --git a/shaders.cc b/shaders.cc
index a8b13e6..1196811 100644
--- a/shaders.cc
+++ b/shaders.cc
@@ -476,6 +476,7 @@ T_ShaderPipeline T_ShaderManager::pipeline(
 	return T_ShaderPipeline{ int32_t( index ) };
 }
 
+/*----------------------------------------------------------------------------*/
 
 void T_ShaderManager::update( )
 {
@@ -834,3 +835,84 @@ void T_ShaderManager::resetProgram(
 		}
 	}
 }
+
+/*----------------------------------------------------------------------------*/
+
+void T_ShaderManager::makeUI( )
+{
+	if ( !uiEnabled_ ) {
+		return;
+	}
+
+	auto const& dspSize( ImGui::GetIO( ).DisplaySize );
+	ImGui::SetNextWindowSize( ImVec2( dspSize.x , 150 ) ,
+			ImGuiSetCond_Once );
+	ImGui::SetNextWindowPos( ImVec2( 0 , dspSize.y - 150 ) ,
+			ImGuiSetCond_Once );
+	ImGui::Begin( "Shaders" );
+
+	const auto n( std::count_if( programs_.begin( ) , programs_.end( ) ,
+			[]( auto const& p ) { return !p.references.empty( ); } ) );
+
+	std::vector< size_t > indices;
+	const auto rn = programs_.size( );
+	for ( auto i = 0u ; i < rn ; i ++ ) {
+		if ( !programs_[ i ].references.empty( ) ) {
+			indices.push_back( i );
+		}
+	}
+	std::sort( indices.begin( ) , indices.end( ) ,
+		[this]( size_t a , size_t b ) {
+			auto const& pa( programs_[ a ] );
+			auto const& pb( programs_[ b ] );
+			if ( pa.code.errors.size( ) != pb.code.errors.size( ) ) {
+				return pa.code.errors.size( ) > pb.code.errors.size( );
+			}
+			if ( pa.references.size( ) != pb.references.size( ) ) {
+				return pa.references.size( ) > pb.references.size( );
+			}
+			return programs_[ a ].name < programs_[ b ].name;
+		} );
+
+	for ( auto i = 0u ; i < n ; i ++ ) {
+		auto const& program( programs_[ indices[ i ] ] );
+		const auto nErrors( program.code.errors.size( ) );
+
+		const bool open( nErrors
+				? ImGui::TreeNodeEx( &program , ImGuiTreeNodeFlags_OpenOnArrow
+						| ImGuiTreeNodeFlags_OpenOnDoubleClick , "%s" ,
+					program.name.c_str( ) )
+				: false );
+
+		if ( !nErrors ) {
+			ImGui::Text( "%s" , program.name.c_str( ) );
+		}
+
+		ImGui::SameLine( 400 );
+		ImGui::Text( "Usage: %zu" , program.references.size( ) );
+		ImGui::SameLine( 550 );
+		if ( program.code.errors.empty( ) ) {
+			ImGui::PushStyleColor( ImGuiCol_Text , ImVec4( .6 , 1 , .6 , 1 ) );
+			ImGui::Text( "No errors" );
+		} else {
+			ImGui::PushStyleColor( ImGuiCol_Text , ImVec4( 1 , .6 , .6 , 1 ) );
+			ImGui::Text( "%zu error%s" , nErrors , nErrors > 1 ? "s" : "" );
+		}
+		ImGui::PopStyleColor( );
+
+		if ( open ) {
+			for ( auto const& err : program.code.errors ) {
+				ImGui::NewLine( );
+				ImGui::SameLine( 50 );
+				ImGui::Text( "%s" , err.source.c_str( ) );
+				ImGui::SameLine( 250 );
+				ImGui::Text( "line %d" , err.line );
+				ImGui::SameLine( 370 );
+				ImGui::Text( "%s" , err.error.c_str( ) );
+			}
+			ImGui::TreePop( );
+		}
+	}
+
+	ImGui::End( );
+}
diff --git a/shaders.hh b/shaders.hh
index 589a8ce..86aa7e3 100644
--- a/shaders.hh
+++ b/shaders.hh
@@ -117,6 +117,10 @@ struct T_ShaderManager
 
 	void update( );
 
+	void makeUI( );
+	bool& uiEnabled( )
+		{ return uiEnabled_; }
+
     private:
 	struct T_Pipeline_
 	{
@@ -135,6 +139,8 @@ struct T_ShaderManager
 		std::unique_ptr< T_WatchedFiles > watch;
 	};
 
+	bool uiEnabled_ = false;
+
 	std::vector< T_Pipeline_ > pipelines_;
 	std::map< std::string , uint32_t > pipelineIndex_;