diff --git a/src/Magnum/GL/Context.cpp b/src/Magnum/GL/Context.cpp
index 4c825c516..7a438e941 100644
--- a/src/Magnum/GL/Context.cpp
+++ b/src/Magnum/GL/Context.cpp
@@ -72,455 +72,464 @@ using namespace Containers::Literals;
    to be sorted alphabetically. */
 namespace {
 
-#define _extension(vendor, extension)                           \
-    {Extensions::vendor::extension::Index, Extensions::vendor::extension::requiredVersion(), Extensions::vendor::extension::coreVersion(), Extensions::vendor::extension::string()}
 #ifndef MAGNUM_TARGET_GLES
 constexpr Extension ExtensionList[]{
-    _extension(AMD,sample_positions),
-    _extension(AMD,shader_explicit_vertex_parameter),
-    _extension(AMD,shader_trinary_minmax),
-    _extension(AMD,transform_feedback3_lines_triangles),
-    _extension(AMD,vertex_shader_layer),
-    _extension(ARB,ES3_2_compatibility),
-    _extension(ARB,bindless_texture),
-    _extension(ARB,compute_variable_group_size),
-    _extension(ARB,robustness),
-    _extension(ARB,robustness_application_isolation),
-    _extension(ARB,robustness_isolation),
-    _extension(ARB,robustness_share_group_isolation),
-    _extension(ARB,sample_locations),
-    _extension(ARB,seamless_cubemap_per_texture),
-    _extension(ARB,sparse_buffer),
-    _extension(ARB,sparse_texture),
-    _extension(ATI,texture_mirror_once),
-    _extension(EXT,debug_label),
-    _extension(EXT,debug_marker),
-    _extension(EXT,shader_integer_mix),
-    _extension(EXT,texture_compression_dxt1),
-    _extension(EXT,texture_compression_s3tc),
-    _extension(EXT,texture_filter_anisotropic),
-    _extension(EXT,texture_mirror_clamp),
-    _extension(EXT,texture_sRGB_R8),
-    _extension(EXT,texture_sRGB_decode),
-    _extension(GREMEDY,string_marker),
-    _extension(KHR,blend_equation_advanced),
-    _extension(KHR,blend_equation_advanced_coherent),
-    _extension(KHR,texture_compression_astc_hdr),
-    _extension(KHR,texture_compression_astc_ldr),
-    _extension(KHR,texture_compression_astc_sliced_3d),
-    _extension(NV,fragment_shader_barycentric),
-    _extension(NV,sample_locations),
-    _extension(OVR,multiview),
-    _extension(OVR,multiview2)};
+    Extensions::AMD::sample_positions{},
+    Extensions::AMD::shader_explicit_vertex_parameter{},
+    Extensions::AMD::shader_trinary_minmax{},
+    Extensions::AMD::transform_feedback3_lines_triangles{},
+    Extensions::AMD::vertex_shader_layer{},
+    Extensions::ARB::ES3_2_compatibility{},
+    Extensions::ARB::bindless_texture{},
+    Extensions::ARB::compute_variable_group_size{},
+    Extensions::ARB::robustness{},
+    Extensions::ARB::robustness_application_isolation{},
+    Extensions::ARB::robustness_isolation{},
+    Extensions::ARB::robustness_share_group_isolation{},
+    Extensions::ARB::sample_locations{},
+    Extensions::ARB::seamless_cubemap_per_texture{},
+    Extensions::ARB::sparse_buffer{},
+    Extensions::ARB::sparse_texture{},
+    Extensions::ATI::texture_mirror_once{},
+    Extensions::EXT::debug_label{},
+    Extensions::EXT::debug_marker{},
+    Extensions::EXT::shader_integer_mix{},
+    Extensions::EXT::texture_compression_dxt1{},
+    Extensions::EXT::texture_compression_s3tc{},
+    Extensions::EXT::texture_filter_anisotropic{},
+    Extensions::EXT::texture_mirror_clamp{},
+    Extensions::EXT::texture_sRGB_R8{},
+    Extensions::EXT::texture_sRGB_decode{},
+    Extensions::GREMEDY::string_marker{},
+    Extensions::KHR::blend_equation_advanced{},
+    Extensions::KHR::blend_equation_advanced_coherent{},
+    Extensions::KHR::texture_compression_astc_hdr{},
+    Extensions::KHR::texture_compression_astc_ldr{},
+    Extensions::KHR::texture_compression_astc_sliced_3d{},
+    Extensions::NV::fragment_shader_barycentric{},
+    Extensions::NV::sample_locations{},
+    Extensions::OVR::multiview{},
+    Extensions::OVR::multiview2{}
+};
 constexpr Extension ExtensionList300[]{
-    _extension(ARB,color_buffer_float),
-    _extension(ARB,depth_buffer_float),
-    _extension(ARB,framebuffer_object),
-    _extension(ARB,framebuffer_sRGB),
-    _extension(ARB,half_float_pixel),
-    _extension(ARB,half_float_vertex),
-    _extension(ARB,map_buffer_range),
-    _extension(ARB,texture_float),
-    _extension(ARB,texture_rg),
-    _extension(ARB,vertex_array_object),
-    _extension(EXT,draw_buffers2),
-    _extension(EXT,gpu_shader4),
-    _extension(EXT,packed_float),
-    _extension(EXT,texture_array),
-    _extension(EXT,texture_compression_rgtc),
-    _extension(EXT,texture_integer),
-    _extension(EXT,texture_shared_exponent),
-    _extension(EXT,transform_feedback),
-    _extension(MAGNUM,shader_vertex_id),
-    _extension(NV,conditional_render),
-    _extension(NV,depth_buffer_float)};
+    Extensions::ARB::color_buffer_float{},
+    Extensions::ARB::depth_buffer_float{},
+    Extensions::ARB::framebuffer_object{},
+    Extensions::ARB::framebuffer_sRGB{},
+    Extensions::ARB::half_float_pixel{},
+    Extensions::ARB::half_float_vertex{},
+    Extensions::ARB::map_buffer_range{},
+    Extensions::ARB::texture_float{},
+    Extensions::ARB::texture_rg{},
+    Extensions::ARB::vertex_array_object{},
+    Extensions::EXT::draw_buffers2{},
+    Extensions::EXT::gpu_shader4{},
+    Extensions::EXT::packed_float{},
+    Extensions::EXT::texture_array{},
+    Extensions::EXT::texture_compression_rgtc{},
+    Extensions::EXT::texture_integer{},
+    Extensions::EXT::texture_shared_exponent{},
+    Extensions::EXT::transform_feedback{},
+    Extensions::MAGNUM::shader_vertex_id{},
+    Extensions::NV::conditional_render{},
+    Extensions::NV::depth_buffer_float{}
+};
 constexpr Extension ExtensionList310[]{
-    _extension(ARB,copy_buffer),
-    _extension(ARB,draw_instanced),
-    _extension(ARB,texture_buffer_object),
-    _extension(ARB,texture_rectangle),
-    _extension(ARB,uniform_buffer_object),
-    _extension(EXT,texture_snorm),
-    _extension(NV,primitive_restart)};
+    Extensions::ARB::copy_buffer{},
+    Extensions::ARB::draw_instanced{},
+    Extensions::ARB::texture_buffer_object{},
+    Extensions::ARB::texture_rectangle{},
+    Extensions::ARB::uniform_buffer_object{},
+    Extensions::EXT::texture_snorm{},
+    Extensions::NV::primitive_restart{}
+};
 constexpr Extension ExtensionList320[]{
-    _extension(ARB,depth_clamp),
-    _extension(ARB,draw_elements_base_vertex),
-    _extension(ARB,fragment_coord_conventions),
-    _extension(ARB,geometry_shader4),
-    _extension(ARB,provoking_vertex),
-    _extension(ARB,seamless_cube_map),
-    _extension(ARB,sync),
-    _extension(ARB,texture_multisample),
-    _extension(ARB,vertex_array_bgra)};
+    Extensions::ARB::depth_clamp{},
+    Extensions::ARB::draw_elements_base_vertex{},
+    Extensions::ARB::fragment_coord_conventions{},
+    Extensions::ARB::geometry_shader4{},
+    Extensions::ARB::provoking_vertex{},
+    Extensions::ARB::seamless_cube_map{},
+    Extensions::ARB::sync{},
+    Extensions::ARB::texture_multisample{},
+    Extensions::ARB::vertex_array_bgra{}
+};
 constexpr Extension ExtensionList330[]{
-    _extension(ARB,blend_func_extended),
-    _extension(ARB,explicit_attrib_location),
-    _extension(ARB,instanced_arrays),
-    _extension(ARB,occlusion_query2),
-    _extension(ARB,sampler_objects),
-    _extension(ARB,shader_bit_encoding),
-    _extension(ARB,texture_rgb10_a2ui),
-    _extension(ARB,texture_swizzle),
-    _extension(ARB,timer_query),
-    _extension(ARB,vertex_type_2_10_10_10_rev)};
+    Extensions::ARB::blend_func_extended{},
+    Extensions::ARB::explicit_attrib_location{},
+    Extensions::ARB::instanced_arrays{},
+    Extensions::ARB::occlusion_query2{},
+    Extensions::ARB::sampler_objects{},
+    Extensions::ARB::shader_bit_encoding{},
+    Extensions::ARB::texture_rgb10_a2ui{},
+    Extensions::ARB::texture_swizzle{},
+    Extensions::ARB::timer_query{},
+    Extensions::ARB::vertex_type_2_10_10_10_rev{}
+};
 constexpr Extension ExtensionList400[]{
-    _extension(ARB,draw_buffers_blend),
-    _extension(ARB,draw_indirect),
-    _extension(ARB,gpu_shader5),
-    _extension(ARB,gpu_shader_fp64),
-    _extension(ARB,sample_shading),
-    _extension(ARB,shader_subroutine),
-    _extension(ARB,tessellation_shader),
-    _extension(ARB,texture_buffer_object_rgb32),
-    _extension(ARB,texture_cube_map_array),
-    _extension(ARB,texture_gather),
-    _extension(ARB,texture_query_lod),
-    _extension(ARB,transform_feedback2),
-    _extension(ARB,transform_feedback3)};
+    Extensions::ARB::draw_buffers_blend{},
+    Extensions::ARB::draw_indirect{},
+    Extensions::ARB::gpu_shader5{},
+    Extensions::ARB::gpu_shader_fp64{},
+    Extensions::ARB::sample_shading{},
+    Extensions::ARB::shader_subroutine{},
+    Extensions::ARB::tessellation_shader{},
+    Extensions::ARB::texture_buffer_object_rgb32{},
+    Extensions::ARB::texture_cube_map_array{},
+    Extensions::ARB::texture_gather{},
+    Extensions::ARB::texture_query_lod{},
+    Extensions::ARB::transform_feedback2{},
+    Extensions::ARB::transform_feedback3{}
+};
 constexpr Extension ExtensionList410[]{
-    _extension(ARB,ES2_compatibility),
-    _extension(ARB,get_program_binary),
-    _extension(ARB,separate_shader_objects),
-    _extension(ARB,shader_precision),
-    _extension(ARB,vertex_attrib_64bit),
-    _extension(ARB,viewport_array)};
+    Extensions::ARB::ES2_compatibility{},
+    Extensions::ARB::get_program_binary{},
+    Extensions::ARB::separate_shader_objects{},
+    Extensions::ARB::shader_precision{},
+    Extensions::ARB::vertex_attrib_64bit{},
+    Extensions::ARB::viewport_array{}
+};
 constexpr Extension ExtensionList420[]{
-    _extension(ARB,base_instance),
-    _extension(ARB,compressed_texture_pixel_storage),
-    _extension(ARB,conservative_depth),
-    _extension(ARB,internalformat_query),
-    _extension(ARB,map_buffer_alignment),
-    _extension(ARB,shader_atomic_counters),
-    _extension(ARB,shader_image_load_store),
-    _extension(ARB,shading_language_420pack),
+    Extensions::ARB::base_instance{},
+    Extensions::ARB::compressed_texture_pixel_storage{},
+    Extensions::ARB::conservative_depth{},
+    Extensions::ARB::internalformat_query{},
+    Extensions::ARB::map_buffer_alignment{},
+    Extensions::ARB::shader_atomic_counters{},
+    Extensions::ARB::shader_image_load_store{},
+    Extensions::ARB::shading_language_420pack{},
     /* Mentioned in GLSL 4.20 specs as newly added */
-    _extension(ARB,shading_language_packing),
-    _extension(ARB,texture_compression_bptc),
-    _extension(ARB,texture_storage),
-    _extension(ARB,transform_feedback_instanced)};
+    Extensions::ARB::shading_language_packing{},
+    Extensions::ARB::texture_compression_bptc{},
+    Extensions::ARB::texture_storage{},
+    Extensions::ARB::transform_feedback_instanced{}
+};
 constexpr Extension ExtensionList430[]{
-    _extension(ARB,ES3_compatibility),
-    _extension(ARB,arrays_of_arrays),
-    _extension(ARB,clear_buffer_object),
-    _extension(ARB,compute_shader),
-    _extension(ARB,copy_image),
-    _extension(ARB,explicit_uniform_location),
-    _extension(ARB,fragment_layer_viewport),
-    _extension(ARB,framebuffer_no_attachments),
-    _extension(ARB,internalformat_query2),
-    _extension(ARB,invalidate_subdata),
-    _extension(ARB,multi_draw_indirect),
-    _extension(ARB,program_interface_query),
-    _extension(ARB,robust_buffer_access_behavior),
-    _extension(ARB,shader_image_size),
-    _extension(ARB,shader_storage_buffer_object),
-    _extension(ARB,stencil_texturing),
-    _extension(ARB,texture_buffer_range),
-    _extension(ARB,texture_query_levels),
-    _extension(ARB,texture_storage_multisample),
-    _extension(ARB,texture_view),
-    _extension(ARB,vertex_attrib_binding),
-    _extension(KHR,debug)};
+    Extensions::ARB::ES3_compatibility{},
+    Extensions::ARB::arrays_of_arrays{},
+    Extensions::ARB::clear_buffer_object{},
+    Extensions::ARB::compute_shader{},
+    Extensions::ARB::copy_image{},
+    Extensions::ARB::explicit_uniform_location{},
+    Extensions::ARB::fragment_layer_viewport{},
+    Extensions::ARB::framebuffer_no_attachments{},
+    Extensions::ARB::internalformat_query2{},
+    Extensions::ARB::invalidate_subdata{},
+    Extensions::ARB::multi_draw_indirect{},
+    Extensions::ARB::program_interface_query{},
+    Extensions::ARB::robust_buffer_access_behavior{},
+    Extensions::ARB::shader_image_size{},
+    Extensions::ARB::shader_storage_buffer_object{},
+    Extensions::ARB::stencil_texturing{},
+    Extensions::ARB::texture_buffer_range{},
+    Extensions::ARB::texture_query_levels{},
+    Extensions::ARB::texture_storage_multisample{},
+    Extensions::ARB::texture_view{},
+    Extensions::ARB::vertex_attrib_binding{},
+    Extensions::KHR::debug{}
+};
 constexpr Extension ExtensionList440[]{
-    _extension(ARB,buffer_storage),
-    _extension(ARB,clear_texture),
-    _extension(ARB,enhanced_layouts),
-    _extension(ARB,multi_bind),
-    _extension(ARB,query_buffer_object),
-    _extension(ARB,texture_mirror_clamp_to_edge),
-    _extension(ARB,texture_stencil8),
-    _extension(ARB,vertex_type_10f_11f_11f_rev)};
+    Extensions::ARB::buffer_storage{},
+    Extensions::ARB::clear_texture{},
+    Extensions::ARB::enhanced_layouts{},
+    Extensions::ARB::multi_bind{},
+    Extensions::ARB::query_buffer_object{},
+    Extensions::ARB::texture_mirror_clamp_to_edge{},
+    Extensions::ARB::texture_stencil8{},
+    Extensions::ARB::vertex_type_10f_11f_11f_rev{}
+};
 constexpr Extension ExtensionList450[]{
-    _extension(ARB,ES3_1_compatibility),
-    _extension(ARB,clip_control),
-    _extension(ARB,conditional_render_inverted),
-    _extension(ARB,cull_distance),
-    _extension(ARB,derivative_control),
-    _extension(ARB,direct_state_access),
-    _extension(ARB,get_texture_sub_image),
-    _extension(ARB,shader_texture_image_samples),
-    _extension(ARB,texture_barrier),
-    _extension(KHR,context_flush_control),
-    _extension(KHR,robustness)};
+    Extensions::ARB::ES3_1_compatibility{},
+    Extensions::ARB::clip_control{},
+    Extensions::ARB::conditional_render_inverted{},
+    Extensions::ARB::cull_distance{},
+    Extensions::ARB::derivative_control{},
+    Extensions::ARB::direct_state_access{},
+    Extensions::ARB::get_texture_sub_image{},
+    Extensions::ARB::shader_texture_image_samples{},
+    Extensions::ARB::texture_barrier{},
+    Extensions::KHR::context_flush_control{},
+    Extensions::KHR::robustness{}
+};
 constexpr Extension ExtensionList460[]{
-    _extension(ARB,gl_spirv),
-    _extension(ARB,indirect_parameters),
-    _extension(ARB,pipeline_statistics_query),
-    _extension(ARB,polygon_offset_clamp),
-    _extension(ARB,shader_atomic_counter_ops),
-    _extension(ARB,shader_draw_parameters),
-    _extension(ARB,shader_group_vote),
-    _extension(ARB,spirv_extensions),
-    _extension(ARB,texture_filter_anisotropic),
-    _extension(ARB,transform_feedback_overflow_query),
-    _extension(KHR,no_error)};
+    Extensions::ARB::gl_spirv{},
+    Extensions::ARB::indirect_parameters{},
+    Extensions::ARB::pipeline_statistics_query{},
+    Extensions::ARB::polygon_offset_clamp{},
+    Extensions::ARB::shader_atomic_counter_ops{},
+    Extensions::ARB::shader_draw_parameters{},
+    Extensions::ARB::shader_group_vote{},
+    Extensions::ARB::spirv_extensions{},
+    Extensions::ARB::texture_filter_anisotropic{},
+    Extensions::ARB::transform_feedback_overflow_query{},
+    Extensions::KHR::no_error{}
+};
 #elif defined(MAGNUM_TARGET_WEBGL)
 constexpr Extension ExtensionList[]{
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,clip_cull_distance),
+    Extensions::EXT::clip_cull_distance{},
     #endif
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,color_buffer_float),
+    Extensions::EXT::color_buffer_float{},
     #endif
     #ifdef MAGNUM_TARGET_GLES2
-    _extension(EXT,disjoint_timer_query),
+    Extensions::EXT::disjoint_timer_query{},
     #endif
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,disjoint_timer_query_webgl2),
+    Extensions::EXT::disjoint_timer_query_webgl2{},
     #endif
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,draw_buffers_indexed),
+    Extensions::EXT::draw_buffers_indexed{},
     #endif
-    _extension(EXT,float_blend),
-    _extension(EXT,texture_compression_bptc),
-    _extension(EXT,texture_compression_rgtc),
-    _extension(EXT,texture_filter_anisotropic),
-    _extension(EXT,texture_norm16),
-    _extension(OES,texture_float_linear),
+    Extensions::EXT::float_blend{},
+    Extensions::EXT::texture_compression_bptc{},
+    Extensions::EXT::texture_compression_rgtc{},
+    Extensions::EXT::texture_filter_anisotropic{},
+    Extensions::EXT::texture_norm16{},
+    Extensions::OES::texture_float_linear{},
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(OVR,multiview2),
+    Extensions::OVR::multiview2{},
     #endif
-    _extension(WEBGL,blend_equation_advanced_coherent),
-    _extension(WEBGL,compressed_texture_astc),
-    _extension(WEBGL,compressed_texture_pvrtc),
-    _extension(WEBGL,compressed_texture_s3tc),
-    _extension(WEBGL,compressed_texture_s3tc_srgb),
-    _extension(WEBGL,debug_renderer_info),
-    _extension(WEBGL,debug_shaders),
+    Extensions::WEBGL::blend_equation_advanced_coherent{},
+    Extensions::WEBGL::compressed_texture_astc{},
+    Extensions::WEBGL::compressed_texture_pvrtc{},
+    Extensions::WEBGL::compressed_texture_s3tc{},
+    Extensions::WEBGL::compressed_texture_s3tc_srgb{},
+    Extensions::WEBGL::debug_renderer_info{},
+    Extensions::WEBGL::debug_shaders{},
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(WEBGL,draw_instanced_base_vertex_base_instance),
+    Extensions::WEBGL::draw_instanced_base_vertex_base_instance{},
     #endif
-    _extension(WEBGL,lose_context),
-    _extension(WEBGL,multi_draw),
+    Extensions::WEBGL::lose_context{},
+    Extensions::WEBGL::multi_draw{},
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(WEBGL,multi_draw_instanced_base_vertex_base_instance)
+    Extensions::WEBGL::multi_draw_instanced_base_vertex_base_instance{},
     #endif
 };
 constexpr Extension ExtensionListES300[]{
     #ifdef MAGNUM_TARGET_GLES2
-    _extension(ANGLE,instanced_arrays),
-    _extension(EXT,blend_minmax),
-    _extension(EXT,color_buffer_half_float),
-    _extension(EXT,frag_depth),
-    _extension(EXT,sRGB),
-    _extension(EXT,shader_texture_lod),
+    Extensions::ANGLE::instanced_arrays{},
+    Extensions::EXT::blend_minmax{},
+    Extensions::EXT::color_buffer_half_float{},
+    Extensions::EXT::frag_depth{},
+    Extensions::EXT::sRGB{},
+    Extensions::EXT::shader_texture_lod{},
     #endif
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(MAGNUM,shader_vertex_id),
+    Extensions::MAGNUM::shader_vertex_id{},
     #endif
     #ifdef MAGNUM_TARGET_GLES2
-    _extension(OES,element_index_uint),
-    _extension(OES,fbo_render_mipmap),
-    _extension(OES,standard_derivatives),
-    _extension(OES,texture_float),
-    _extension(OES,texture_half_float),
-    _extension(OES,texture_half_float_linear),
-    _extension(OES,vertex_array_object),
-    _extension(WEBGL,color_buffer_float),
-    _extension(WEBGL,depth_texture),
-    _extension(WEBGL,draw_buffers)
+    Extensions::OES::element_index_uint{},
+    Extensions::OES::fbo_render_mipmap{},
+    Extensions::OES::standard_derivatives{},
+    Extensions::OES::texture_float{},
+    Extensions::OES::texture_half_float{},
+    Extensions::OES::texture_half_float_linear{},
+    Extensions::OES::vertex_array_object{},
+    Extensions::WEBGL::color_buffer_float{},
+    Extensions::WEBGL::depth_texture{},
+    Extensions::WEBGL::draw_buffers{},
     #endif
 };
 #else
 constexpr Extension ExtensionList[]{
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(ANDROID,extension_pack_es31a),
+    Extensions::ANDROID::extension_pack_es31a{},
     #endif
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(ANGLE,base_vertex_base_instance),
+    Extensions::ANGLE::base_vertex_base_instance{},
     #endif
-    _extension(ANGLE,multi_draw),
-    _extension(ANGLE,texture_compression_dxt1),
-    _extension(ANGLE,texture_compression_dxt3),
-    _extension(ANGLE,texture_compression_dxt5),
-    _extension(APPLE,clip_distance),
-    _extension(APPLE,texture_format_BGRA8888),
-    _extension(ARM,shader_framebuffer_fetch),
-    _extension(ARM,shader_framebuffer_fetch_depth_stencil),
+    Extensions::ANGLE::multi_draw{},
+    Extensions::ANGLE::texture_compression_dxt1{},
+    Extensions::ANGLE::texture_compression_dxt3{},
+    Extensions::ANGLE::texture_compression_dxt5{},
+    Extensions::APPLE::clip_distance{},
+    Extensions::APPLE::texture_format_BGRA8888{},
+    Extensions::ARM::shader_framebuffer_fetch{},
+    Extensions::ARM::shader_framebuffer_fetch_depth_stencil{},
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,clip_cull_distance),
+    Extensions::EXT::clip_cull_distance{},
     #endif
-    _extension(EXT,debug_label),
-    _extension(EXT,debug_marker),
-    _extension(EXT,disjoint_timer_query),
-    _extension(EXT,draw_elements_base_vertex),
-    _extension(EXT,multi_draw_arrays),
-    _extension(EXT,multisampled_render_to_texture),
-    _extension(EXT,polygon_offset_clamp),
-    _extension(EXT,pvrtc_sRGB),
-    _extension(EXT,read_format_bgra),
-    _extension(EXT,robustness),
-    _extension(EXT,sRGB_write_control),
-    _extension(EXT,separate_shader_objects),
-    _extension(EXT,shader_framebuffer_fetch),
+    Extensions::EXT::debug_label{},
+    Extensions::EXT::debug_marker{},
+    Extensions::EXT::disjoint_timer_query{},
+    Extensions::EXT::draw_elements_base_vertex{},
+    Extensions::EXT::multi_draw_arrays{},
+    Extensions::EXT::multisampled_render_to_texture{},
+    Extensions::EXT::polygon_offset_clamp{},
+    Extensions::EXT::pvrtc_sRGB{},
+    Extensions::EXT::read_format_bgra{},
+    Extensions::EXT::robustness{},
+    Extensions::EXT::sRGB_write_control{},
+    Extensions::EXT::separate_shader_objects{},
+    Extensions::EXT::shader_framebuffer_fetch{},
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,shader_integer_mix),
+    Extensions::EXT::shader_integer_mix{},
     #endif
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,texture_compression_bptc),
+    Extensions::EXT::texture_compression_bptc{},
     #endif
-    _extension(EXT,texture_compression_dxt1),
+    Extensions::EXT::texture_compression_dxt1{},
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,texture_compression_rgtc),
+    Extensions::EXT::texture_compression_rgtc{},
     #endif
-    _extension(EXT,texture_compression_s3tc),
-    _extension(EXT,texture_compression_s3tc_srgb),
-    _extension(EXT,texture_filter_anisotropic),
-    _extension(EXT,texture_format_BGRA8888),
+    Extensions::EXT::texture_compression_s3tc{},
+    Extensions::EXT::texture_compression_s3tc_srgb{},
+    Extensions::EXT::texture_filter_anisotropic{},
+    Extensions::EXT::texture_format_BGRA8888{},
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,texture_norm16),
-    _extension(EXT,texture_sRGB_R8),
+    Extensions::EXT::texture_norm16{},
+    Extensions::EXT::texture_sRGB_R8{},
     #endif
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,texture_sRGB_RG8),
+    Extensions::EXT::texture_sRGB_RG8{},
     #endif
-    _extension(EXT,texture_sRGB_decode),
-    _extension(IMG,texture_compression_pvrtc),
-    _extension(KHR,blend_equation_advanced_coherent),
-    _extension(KHR,context_flush_control),
-    _extension(KHR,no_error),
-    _extension(KHR,texture_compression_astc_hdr),
-    _extension(KHR,texture_compression_astc_sliced_3d),
+    Extensions::EXT::texture_sRGB_decode{},
+    Extensions::IMG::texture_compression_pvrtc{},
+    Extensions::KHR::blend_equation_advanced_coherent{},
+    Extensions::KHR::context_flush_control{},
+    Extensions::KHR::no_error{},
+    Extensions::KHR::texture_compression_astc_hdr{},
+    Extensions::KHR::texture_compression_astc_sliced_3d{},
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(NV,fragment_shader_barycentric),
+    Extensions::NV::fragment_shader_barycentric{},
     #endif
-    _extension(NV,polygon_mode),
-    _extension(NV,read_buffer_front),
-    _extension(NV,read_depth),
-    _extension(NV,read_depth_stencil),
-    _extension(NV,read_stencil),
-    _extension(NV,sample_locations),
+    Extensions::NV::polygon_mode{},
+    Extensions::NV::read_buffer_front{},
+    Extensions::NV::read_depth{},
+    Extensions::NV::read_depth_stencil{},
+    Extensions::NV::read_stencil{},
+    Extensions::NV::sample_locations{},
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(NV,shader_noperspective_interpolation),
+    Extensions::NV::shader_noperspective_interpolation{},
     #endif
-    _extension(NV,texture_border_clamp),
-    _extension(OES,depth32),
-    _extension(OES,draw_elements_base_vertex),
-    _extension(OES,mapbuffer),
-    _extension(OES,stencil1),
-    _extension(OES,stencil4),
+    Extensions::NV::texture_border_clamp{},
+    Extensions::OES::depth32{},
+    Extensions::OES::draw_elements_base_vertex{},
+    Extensions::OES::mapbuffer{},
+    Extensions::OES::stencil1{},
+    Extensions::OES::stencil4{},
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(OES,texture_compression_astc),
+    Extensions::OES::texture_compression_astc{},
     #endif
-    _extension(OES,texture_float_linear),
+    Extensions::OES::texture_float_linear{},
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(OVR,multiview),
+    Extensions::OVR::multiview{},
     #endif
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(OVR,multiview2),
+    Extensions::OVR::multiview2{},
     #endif
     };
 constexpr Extension ExtensionListES300[]{
     #ifdef MAGNUM_TARGET_GLES2
-    _extension(ANGLE,depth_texture),
-    _extension(ANGLE,framebuffer_blit),
-    _extension(ANGLE,framebuffer_multisample),
-    _extension(ANGLE,instanced_arrays),
-    _extension(APPLE,framebuffer_multisample),
-    _extension(APPLE,texture_max_level),
-    _extension(ARM,rgba8),
-    _extension(EXT,blend_minmax),
-    _extension(EXT,discard_framebuffer),
-    _extension(EXT,draw_buffers),
-    _extension(EXT,draw_instanced),
-    _extension(EXT,instanced_arrays),
-    _extension(EXT,map_buffer_range),
-    _extension(EXT,occlusion_query_boolean),
-    _extension(EXT,sRGB),
-    _extension(EXT,shader_texture_lod),
-    _extension(EXT,shadow_samplers),
-    _extension(EXT,texture_rg),
-    _extension(EXT,texture_storage),
-    _extension(EXT,texture_type_2_10_10_10_REV),
-    _extension(EXT,unpack_subimage),
+    Extensions::ANGLE::depth_texture{},
+    Extensions::ANGLE::framebuffer_blit{},
+    Extensions::ANGLE::framebuffer_multisample{},
+    Extensions::ANGLE::instanced_arrays{},
+    Extensions::APPLE::framebuffer_multisample{},
+    Extensions::APPLE::texture_max_level{},
+    Extensions::ARM::rgba8{},
+    Extensions::EXT::blend_minmax{},
+    Extensions::EXT::discard_framebuffer{},
+    Extensions::EXT::draw_buffers{},
+    Extensions::EXT::draw_instanced{},
+    Extensions::EXT::instanced_arrays{},
+    Extensions::EXT::map_buffer_range{},
+    Extensions::EXT::occlusion_query_boolean{},
+    Extensions::EXT::sRGB{},
+    Extensions::EXT::shader_texture_lod{},
+    Extensions::EXT::shadow_samplers{},
+    Extensions::EXT::texture_rg{},
+    Extensions::EXT::texture_storage{},
+    Extensions::EXT::texture_type_2_10_10_10_REV{},
+    Extensions::EXT::unpack_subimage{},
     #endif
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(MAGNUM,shader_vertex_id),
+    Extensions::MAGNUM::shader_vertex_id{},
     #endif
     #ifdef MAGNUM_TARGET_GLES2
-    _extension(NV,draw_buffers),
-    _extension(NV,draw_instanced),
-    _extension(NV,fbo_color_attachments),
-    _extension(NV,framebuffer_blit),
-    _extension(NV,framebuffer_multisample),
-    _extension(NV,instanced_arrays),
-    _extension(NV,pack_subimage),
-    _extension(NV,read_buffer),
-    _extension(NV,shadow_samplers_array),
-    _extension(NV,shadow_samplers_cube),
-    _extension(OES,depth24),
-    _extension(OES,depth_texture),
-    _extension(OES,element_index_uint),
-    _extension(OES,fbo_render_mipmap),
-    _extension(OES,packed_depth_stencil),
-    _extension(OES,required_internalformat),
-    _extension(OES,rgb8_rgba8),
-    _extension(OES,standard_derivatives),
-    _extension(OES,surfaceless_context),
-    _extension(OES,texture_3D),
-    _extension(OES,texture_float),
-    _extension(OES,texture_half_float),
-    _extension(OES,texture_half_float_linear),
-    _extension(OES,texture_npot),
-    _extension(OES,vertex_array_object),
-    _extension(OES,vertex_half_float),
+    Extensions::NV::draw_buffers{},
+    Extensions::NV::draw_instanced{},
+    Extensions::NV::fbo_color_attachments{},
+    Extensions::NV::framebuffer_blit{},
+    Extensions::NV::framebuffer_multisample{},
+    Extensions::NV::instanced_arrays{},
+    Extensions::NV::pack_subimage{},
+    Extensions::NV::read_buffer{},
+    Extensions::NV::shadow_samplers_array{},
+    Extensions::NV::shadow_samplers_cube{},
+    Extensions::OES::depth24{},
+    Extensions::OES::depth_texture{},
+    Extensions::OES::element_index_uint{},
+    Extensions::OES::fbo_render_mipmap{},
+    Extensions::OES::packed_depth_stencil{},
+    Extensions::OES::required_internalformat{},
+    Extensions::OES::rgb8_rgba8{},
+    Extensions::OES::standard_derivatives{},
+    Extensions::OES::surfaceless_context{},
+    Extensions::OES::texture_3D{},
+    Extensions::OES::texture_float{},
+    Extensions::OES::texture_half_float{},
+    Extensions::OES::texture_half_float_linear{},
+    Extensions::OES::texture_npot{},
+    Extensions::OES::vertex_array_object{},
+    Extensions::OES::vertex_half_float{},
     #endif
     };
 constexpr Extension ExtensionListES320[]{
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,color_buffer_float),
+    Extensions::EXT::color_buffer_float{},
     #endif
-    _extension(EXT,color_buffer_half_float),
+    Extensions::EXT::color_buffer_half_float{},
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,copy_image),
+    Extensions::EXT::copy_image{},
     #endif
-    _extension(EXT,draw_buffers_indexed),
+    Extensions::EXT::draw_buffers_indexed{},
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,geometry_shader),
+    Extensions::EXT::geometry_shader{},
     #endif
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,gpu_shader5),
+    Extensions::EXT::gpu_shader5{},
     #endif
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,primitive_bounding_box),
+    Extensions::EXT::primitive_bounding_box{},
     #endif
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,shader_io_blocks),
+    Extensions::EXT::shader_io_blocks{},
     #endif
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,tessellation_shader),
+    Extensions::EXT::tessellation_shader{},
     #endif
-    _extension(EXT,texture_border_clamp),
+    Extensions::EXT::texture_border_clamp{},
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,texture_buffer),
+    Extensions::EXT::texture_buffer{},
     #endif
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(EXT,texture_cube_map_array),
+    Extensions::EXT::texture_cube_map_array{},
     #endif
-    _extension(KHR,blend_equation_advanced),
-    _extension(KHR,debug),
-    _extension(KHR,robust_buffer_access_behavior),
-    _extension(KHR,robustness),
-    _extension(KHR,texture_compression_astc_ldr),
+    Extensions::KHR::blend_equation_advanced{},
+    Extensions::KHR::debug{},
+    Extensions::KHR::robust_buffer_access_behavior{},
+    Extensions::KHR::robustness{},
+    Extensions::KHR::texture_compression_astc_ldr{},
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(OES,sample_shading),
+    Extensions::OES::sample_shading{},
     #endif
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(OES,sample_variables),
+    Extensions::OES::sample_variables{},
     #endif
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(OES,shader_image_atomic),
+    Extensions::OES::shader_image_atomic{},
     #endif
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(OES,shader_multisample_interpolation),
+    Extensions::OES::shader_multisample_interpolation{},
     #endif
-    _extension(OES,texture_stencil8),
+    Extensions::OES::texture_stencil8{},
     #ifndef MAGNUM_TARGET_GLES2
-    _extension(OES,texture_storage_multisample_2d_array)
+    Extensions::OES::texture_storage_multisample_2d_array{}
     #endif
     };
 #endif
-#undef _extension
 
 constexpr struct {
     Version version;
diff --git a/src/Magnum/GL/Context.h b/src/Magnum/GL/Context.h
index 45bb43794..c776bee92 100644
--- a/src/Magnum/GL/Context.h
+++ b/src/Magnum/GL/Context.h
@@ -94,9 +94,8 @@ class MAGNUM_GL_EXPORT Extension {
         /** @brief Extension string */
         constexpr const char* string() const { return _string; }
 
-    #ifndef DOXYGEN_GENERATING_OUTPUT
-    constexpr Extension(std::size_t index, Version requiredVersion, Version coreVersion, const char* string): _index{index}, _requiredVersion{requiredVersion}, _coreVersion{coreVersion}, _string{string} {}
-    #endif
+        /** @brief Construct from a compile-time extension */
+        template<class E, class = typename std::enable_if<Implementation::IsExtension<E>::value>::type> constexpr /*implicit*/ Extension(const E&): _index{E::Index}, _requiredVersion{E::requiredVersion()}, _coreVersion{E::coreVersion()}, _string{E::string()} {}
 
     private:
         std::size_t _index;