Changelog

0.5

August 25 2026

Playbit.app

Improved system load when receiving many input events in rapid succession
Added the ability to click on links output to the logging view
Added the ability for signed-in users to publish an app to the Playbit website for easy sharing
Added "sign in" and "sign out" items to macOS menubar
Changed the default remote-control screenshot location to ./_pb/screenshots (relative to the working directory)

Web Runtime

Added keyboard and scroll input support
Improved aperture to now get its "window size" from page layout
Added playbit.run convenience function to JS embedding API
Reduced file size by shipping fewer fonts

C API

Added several new audio playback control functions to playbit/audio.h
- See new PBAudioSoundResume
- See new PBAudioSoundPause
- See new PBAudioSoundTell
- See new PBAudioSoundSeek
- See new PBAudioBufferPlayAfter
- See new PBAudioBufferUpload
- See new PBAudioSoundGetPosition
- See new PBAudioSoundIsPlaying
Improved multiplayer robustness when edit history entries fail to decrypt
Improved multiplayer robustness when receiving certain kinds of invalid edit history entries
Fixed a multiplayer assertion when removing a struct from a list while a peer edits the struct
Added generated multiplayer functions for getting a map's item count
Added generated multiplayer functions for removing an item from a map
Added new PBMPNetChannelOpenAssociatedEx to playbit/multiplayer.h
Added multiline text layout and editing functionality to UI3
Improved UI3 multiplayer-backed input field to better handle selection when replacing multiplayer object
Improved UI3 text selection with multiple input fields to prefer the input field at the same y-level as the mouse
Added U3TextHitTest to playbit/ui3.h
Added U3AttributedStringMake2 to playbit/ui3.h
Added U3BodyUserSelectingText to playbit/ui3.h
Fixed a bug in PBPool where the last item in a chunk could not be looked-up
Added new PBEventType_WGPU_CALLBACK to playbit/event.h

Runtime

Continued to further improve text rendering quality
Added renderer support for rendering text decorations (underlines)
Fixed an bug where the renderer would not be able to render new glyphs after filling a texture atlas
Changed render command AABB and corner radius values to be f32
- This is a breaking ABI change and necessitates recompiling apps to work with this change
Improved canvases to allow being created offscreen
Added new additional audio syscalls to playbit/sys/syscalls/audio.h
- See new PBSysAudioSound type, representing a currently playing sound
- See changed PBSysAudioSetVolume
- See new PBSysAudioSoundPlayback
- See new PBSysAudioSoundTell
- See new PBSysAudioSoundSeek
- See new PBSysAudioBufferPlayAfter
- See new PBSysAudioBufferUpload
- See new PBSysAudioSoundGetPosition
- See new PBSysAudioSoundIsPlaying
Added new PBSysWindowWorkspaceOpenURL to playbit/sys/syscalls/window.h
Added new PBSysGuiPrefsGet and PBSysGuiSignal_PREFS to playbit/sys/syscalls/gui.h
- Used to query about OS like light vs dark theme, accent color, ect
Improved general macOS IO integration reliability
- This improves multiplayer latency dramatically
Added many more cursor styles
Improved quality of WebGPU support
Improved runtime exit to reflect the guest program's exit status as its own

Developer tools

Added pb run --script=<script> for driving apps via the remote-control automation protocol
Changed pb run to run Playbit.app as a child process propagate the app's exit status as its own
Added new pb bundle to process an existing wasm file produced by a different tool
Added new app_res toml key to embed a folder's contents as individual resources automatically

Examples

Added new audio-stream example
Added new boxes math visualization example

Version 0.4

July 20 2026

Playbit.app

Improved the performance of scrolling large program logs
Added the ability to horizontally scroll program logs
Added system URI schema handler for playbit:// to launch an app (with confirmation) by opening a link
Added menubar entry and shortcut for launching an app via a URL

Web Runtime

Improved correctness of event polling internals
Switched to our hardware accelerated WebGPU 2d renderer for UI
- This means that we now also require WebGPU to be supported to run
Fixed PBSysClockRead returning a value with the wrong precision level
Implemented PBSysWindowSetCursor for all styles other than custom image
Fixed an issue where the virtual window could flicker when spanning the full viewport on some systems

C API

Added PBHandleGetInfo and PBHandleGetRights to playbit/handle.h
Added *FeaturesGet, *FeaturesCheck, and *HasFeature functions to several object headers
- See playbit/net.h
- See playbit/thread.h
Added a bunch of math functions to playbit/math.h
Improved correctness of PBMutexRUnlock
Fixed key state query PBKeyPressed, PBKeyRepeated, PBKeyReleased, and PBKeyDown silently not working
Improved PBTimeDurationMilliseconds and PBTimeDurationMicroseconds to round instead of floor
Fixed a situation where PBArena could leak memory
Improved general-purpose-allocator's behavior in out-of-memory situations
Improved PBDraw performance around drawing text
Fixed a situation where PBDraw could leak drawn text strings
Improved PBDraw to throw an assertion when a rectangle bounds are negative or otherwise inverted
Fixed U3Util box not taking stroke thickness into account when calculating its size
Improved layout correctness of U3Flex
Improved UI3 key reuse assert to have a more helpful failure message
Added new U3AttributedStringConcatenateArray to playbit/ui3.h
Added new U3AttributedStringConcatenate to playbit/ui3.h
Improved U3AttributedStringMake to take a PBColor instead of u32
Improved U3AttributedString to better handle the case where it contains no text at all
Improved UI3 to send a final mouse move event to boxes after the cursor leaves its bounds
Fixed U3PrimaryAxisAlignment_SPACE_BETWEEN and U3PrimaryAxisAlignment_SPACE_AROUND having each others behavior
Fixed a couple of cases where UI3 could attempt to draw rectangles with nonsensical bounds
Added special comment to autogenerated multiplayer header to disable clang-format
Improved multiplayer stability and correctness
Added PBMPGetObjectUUID to playbit/multiplayer.h
Added *_deserialize functions to generated and builtin multiplayer types
Added multiplayer schema compiler error disallowing nesting maps directly inside lists
Added PBMPDocCreate2 and PBMPDocOpen2 from playbit/multiplayer.h
- These new functions take a schemaVersion argument
- The previous functions PBMPDocCreate and PBMPDocOpen now use the schema version from your autogenerated header
Changed PBMPImport to return a bool indicating success
Fixed incorrect min constants I8_MIN, I16_MIN, I32_MIN, and I64_MIN

Runtime

Improved text rendering in many situations
Introduced new 2d rendering syscalls with many new capabilities
- See new playbit/sys/syscalls/canvas.h
- Added HDR and wide color gamut support
- Added transparent window support when window canvas background color has an alpha < 1
- Color byte-wise layout is now 0xAAAABBBBGGGGRRRR
- Try out the subset of WebGPU now accessable via the canvas syscalls
Removed old 2d rendering syscall PBSysWindowRendererPackageWrite
Marked PBSysWindowTextplanCreate as deprecated
Added new PBSysWindowTextplanCreate2 to playbit/sys/syscalls/window.h
Added PBSysTextureFormat_RGBAF16 to playbit/sys/syscalls/texture.h
Improved performance when frequently setting mouse cursor style on macOS
Improved reliability of runtime panic log reporting
Fixed PBSysGesturePhase_BEGAN and PBSysGesturePhase_END never firing on macOS
Added new PBSysObjectFeatures to playbit/sys/syscalls/object.h
Added new feature enums to several object headers
- See playbit/sys/syscalls/net.h
- See playbit/sys/syscalls/thread.h
Added new PBSysHandleListFilter flags for PBSysHandleList to playbit/sys/syscalls/handle.h
Fixed PBSysHandleList to only include live handles
Improved PBSysWindowTextplanCreate and PBSysWindowTextplanCreate2 to return PBSysErr_NO_MEM when failing to allocate

Examples

Ported all examples with a graphical user interface to our UI3 library
Added a set of more focused API examples with the prefix api-
Added new example sync3
Added multiplayer support to jump-game example

Version 0.3

June 23 2026

Playbit.app

Made installing new toolchain and examples more robust
Fixed text selection being incorrect after clearing the log

Web Runtime

Introduced playbit.js technology preview
- Intended to allow running unmodified apps with the Playbit runtime running on the web
- Visit https://playbit.app/ for a demo

C API

Added new UI library UI3
- See new playbit/ui3.h
Added new multiplayer sync-ed data library
- See new playbit/multiplayer.h
Added APIs for interacting with Human-Interface Devices (HID) such as gamepads
- See PBGamepadAxis and PBGamepadEvent in playbit/event.h
- See new playbit/hid.h
Added PBNetChannelDirect to playbit/net.h
Added generic TCP/UDP networking PBNetTransport
- See new PBNetTransportOpen in playbit/net.h
- See new PBNetTransportOpenStream in playbit/net.h
- See new PBNetTransportOpenEx in playbit/net.h
- See new PBNetTransportOpenStreamEx in playbit/net.h
- See new PBNetTransportSetKeepAlive in playbit/net.h
Improved the correctness of PBArenaPush
Added PBDrawTextAlign to playbit/draw.h
Added PBDrawSetBackgroundColor to playbit/draw.h
Added various functions for querying a window's mouse and keyboard state
- See new PBWindowGetMousePosition in playbit/window.h
- See new PBKeyPressed in playbit/window.h
- See new PBKeyReleased in playbit/window.h
- See new PBKeyRepeated in playbit/window.h
- See new PBKeyRepeated in playbit/window.h
- See new PBMousePressed in playbit/window.h
- See new PBMouseReleased in playbit/window.h
- See new PBMouseDown in playbit/window.h
- See new PBWindowProcessEvents in playbit/window.h
- See new PBWindowEndFrame in playbit/window.h
Added PBPanicv to playbit/base.h
Fixed compilation error with PBBufSlice
Added various PBStr index finding functions
- See new PBStrIndexOfStr in playbit/string.h
- See new PBStrLastIndexOfStr in playbit/string.h
- See new PBStrIndexOfByte in playbit/string.h
- See new PBStrLastIndexOfByte in playbit/string.h
Added various PBStr numeric parsing functions
- See new PBStrSliceParseInt in playbit/string.h
- See new PBStrSliceParseUInt in playbit/string.h
- See new PBIntOfStr in playbit/string.h
Added various PBStr trimming functions
- See new PBStrSliceTrim in playbit/string.h
- See new PBStrSliceTrimStart in playbit/string.h
- See new PBStrSliceTrimEnd in playbit/string.h
Added various PBMemFind functions
- See new PBMemFindByte in playbit/mem.h
- See new PBMemFindLastByte in playbit/mem.h
- See new PBMemFindSegment in playbit/mem.h
- See new PBMemFindLastSegment in playbit/mem.h
Fixed compilation error with PBCheckStrEq
Fixed potential compilation error with PB_UNREACHABLE
Improved the correctness of PBWindowGetMousePosition
Improved potential link error with some math functions in playbit/math.h
Improved logging behavior to be defined as always logging one full complete message at a time
Renamed PB_GUI_ENABLED define to PB_NO_GUI with approriate behavior change

Runtime

Improved rendering latency and frame pacing
Fixed an issue where popping the root render clip region did not clear clipping
Fixed an issue where SysWindowFrameSyncEnable would not enforce rights control
Fixed an issue where the frame sync signal could continue to fire even after the guest does not want it
Fixed an issue where the runtime event loop could get confused and idle forever
Fixed an issue where unreasonable window sizes could cause a crash
Improved window resize signal to not fire when macOS reported a resize but the window was the same size
Added PBTextPlanLayoutFlags enum to specify already supported text layout flags
Added PBSysWindowSetCursor and various associated types
Added various syscalls for handling window fullscreen state
- See new PBSysWindowFullScreenGet in playbit/sys/syscalls/window.h
- See new PBSysWindowFullScreenSet in playbit/sys/syscalls/window.h
Added various syscalls and associated types for handling GUI presentation
- See new PBSysGuiPresentationGet in playbit/sys/syscalls/gui.h
- See new PBSysGuiPresentationSet in playbit/sys/syscalls/gui.h
Added various syscalls for Human-Interface Devices (HID) such as gamepads
- See new playbit/sys/syscalls/hid.h
- See new PBSysGamepadButton and PBSysGamepadEvent in playbit/sys/syscalls/event.h
Added various syscalls for PBNetTransport
- See new PBSysNetTransportOpenStream in playbit/sys/syscalls/net_transport.h
- See new PBSysNetTransportSetKeepAlive in playbit/sys/syscalls/net_transport.h
Added PBSysTextureFormat_BGRA8
Added syscalls for getting a texture's size
- See new PBSysTextureGetWidth in playbit/sys/syscalls/texture.h
- See new PBSysTextureGetHeight in playbit/sys/syscalls/texture.h
Added syscall for opening file panels (dialogs)
- See new playbit/sys/syscalls/file_panel.h
- See new PBFilePanelEvent in playbit/sys/syscalls/event.h
Added new PBSysFileOpenFlag_TRUNCATE and PBSysFileOpenFlag_EXCLUSIVE
Added new PBSysFileOpenFlag_MODE_USER_RW, PBSysFileOpenFlag_MODE_GROUP_RW, and PBSysFileOpenFlag_MODE_OTHER_RW
Added various syscalls and associated types specifically for creating files:
- See new PBFileCreate in playbit/sys/syscalls/file.h
- See new PBFileCreateOrPanic in playbit/sys/syscalls/file.h
- See new PBFileCreateOrTruncateOrPanic in playbit/sys/syscalls/file.h
Added new helper functions for converting flag open/create types
- See new PBFileModeOfFlags in playbit/sys/syscalls/file.h
- See new PBFileOpenFlagsOfMode in playbit/sys/syscalls/file.h
Fixed an issue where a network connection could fail to reconnect
Fixed an issue where a guest thread could hang upon a network disconnect
Fixed an issue where a connection was not properly disconnected on app exit
Fixed an issue where network messages could be become corrupted and unable to decode
Added PEM-encoded root certificate fields certPem and certPemLen to PBSysNetTransportConfig
Renamed PBSysNetTransportOpenFlags to PBSysNetTransportStreamFlags
Added PBSysNetTransportFlags to PBSysNetTransportConfig
Added PBSysThreadReadRandom to playbit/sys/syscalls/thread.h
Improved no-gui codepaths to shut down faster than before
Enabled use of WASM's expection-handling extension in guest programs
Removed unused PBSysRight_GET_PROPERTY and PBSysRight_SET_PROPERTY
Fixed a case where updating an observer could cause it to miss a signal
Improved SysWindowTextplanCreate to accept a null pointer when len is zero

Developer tools

Improved logging around failure to launch Playbit.app
Fixed an issue where launched Playbit.app would never exit after no-gui program exits
Improved detail in pb run --help message
Fixed an issue where building an app with --no-gui would not be noted in the built app's manifest
Added --colors flag for controlling ANSI color output

Examples

Added notes example
Added sync1 and sync2 examples
Added jump-game example
Fixed an incorrect comment in renderer-package
Improved styling and simplified hello
Slightly simplified game-of-life

Version 0.2

May 7 2026

Errata

A previous version of the 0.2 changelog erroniously said that a new library UI3 had been released. This was incorrect, and this library was instead later released in 0.3.

C API

Added APIs for retrieving resources embedded into your wasm-compiled app
- See PBAppResourceWithName and PBAppResourceAtIndex in playbit/app.h
Added PBAppName to playbit/app.h
Added PBAppId to playbit/app.h
Renamed println to print
- Use PBPrintf for formatted printing without automatic newline
Added APIs for interacting with various window properties
- See playbit/window.h
Changed UIBoxIsClick to be called UIBoxOnClick
Improved initial window presentation behavior
Added PBStrLit for making PBStrSlice from c-string literals
Deprecated previous catch-all PB_STR helper macro
- For usage not covered by PBStrLit try PBStrSliceOf
Added PBStr_FMT and PBStr_FMT_ARG macros for easier println formatting of strings
Added new PBDrawRectWithStroke function to the drawing API
Added new PBDrawTextWithPlan function to the drawing API
Added new PBDrawTexturedRectExt and PBDrawTexturedRectExt2 functions to the drawing API
Added new PBDrawTextLine and PBDrawTextMultiline functions to the drawing API
Improved PBDrawBeginFrame to auto-allocate a draw API context if one is not set
Improved implicit cached text drawing cache implementation in the drawing API
Fixed an issue where usage of the PBArrayAllocAt macro would not compile
Improved PBAnyArrayFree to now make PBArray go into a "null" state
- v becomes NULL, len and cap become 0
Fixed PBArenaFromAllocator ignoring size paramter
Introduced new PBSemaphore
- See new playbit/semaphore.h
Added PBRGB and PBRGBA helper macros for creating PBColor values
Added new PBColorToRGBA8 function
Fixed an issue where PBDateFormat could format a date's month incorrectly
Added new PBDateComponents function
Added new PBTimeZoneUTCOffset2 function
Added new PBRectangleOfRect and PBRectangleOfSize functions

Runtime

Fixed various underlying thread correctness issues on macOS
Fixed a rare deadlock when rendering during a window resize
Improved the situation around some renderer setup race conditions
Added various syscalls for audio playback
- playbit/sys/syscalls/audio.h
Added various syscalls for filesystem access
- See new playbit/sys/syscalls/file.h
- See new playbit/sys/syscalls/file_list.h
Added clipboard access syscalls to the window object
- Syscall: PBSysWindowClipboardWriteText
- Syscall: PBSysWindowClipboardReadText
- See playbit/sys/syscalls/window.h
Added texture creation and modification syscalls
- See new playbit/sys/syscalls/texture.h
- See playbit/sys/syscalls/window.h
Added various syscalls for Playbit network access
- See new playbit/sys/syscalls/net.h
- See new playbit/sys/syscalls/net_session.h
Removed "scene graph" rendering syscalls
Fixed floating point value handling of PBSysWindowSetRect
Fixed monotonic clock not advancing when system is asleep on macOS

Playbit.app

Improved display of recent apps to be sorted
Added release notes to log shown on startup
Fixed a bug which could cause some log messages to crash the app

Developer tools

Increased default wasm stack size to 512 KiB
Added command line flag --stack-size