ARC 2026.04.11.00 (Pro, Runtime And Free)
Change Release Notes
This update is packed with polish, performance, and a whole lot of "finally, that’s fixed!" moments. Let’s dig in
EZ-B Emulator Gets Smarter
The EZ-B emulator just leveled up with improved debugging and rock-solid stability. It’s now a better playground for testing without surprises.
Boot Logs Now Where You Actually Need Them
Boot logs are no longer hiding in a file somewhere - they now show up directly in the debug log so you can see what’s happening in real time.
Blockly Crash-Proofing Upgrade
Ever had Blockly explode because of a weird character in a name? Not anymore.
User-facing strings (control names, actions, filenames, variables, etc.) are now safely escaped before being sent to the browser. Special characters like quotes, slashes, and even sneaky Unicode line separators won’t break your UI anymore.
Servo Selection Just Got Friendly
Blockly now shows human-readable servo names in port selection - pulled from:
- Project Options (port summaries)
- 3D Bit Designer
No more guessing what port does what.
Deep Stability & Memory Cleanup
A whole bunch of behind-the-scenes fixes to keep ARC running smoother and longer:
- Fixed multiple null reference crashes
- Eliminated resource leaks (Registry, Graphics, SerialPort, Images, ColorDialog, etc.)
- Fixed UTF-8 encoding issues (no more broken non-ASCII text)
- Improved error handling across key forms and systems
- Corrected plugin GUID handling (no more sending full paths by mistake)
Navigation Messaging System Overhaul
Major improvements for performance and thread safety:
- Fixed race conditions in event handling (no more random crashes)
- Atomic frame counting using
Interlocked - O(1) queue clearing (huge performance win)
- Reduced allocations during scan processing
This makes navigation data handling faster, safer, and more scalable.
Blockly + Scripting Evolution
- Blockly blocks now link directly to their online manual pages
- Groups are now sorted by category (Blockly, JavaScript, Python)
- Added group type dropdown selection
- Early support for multi-language activities (Blockly, Python, JavaScript )
UI Improvements & Polish
- Theme manager now has cleaner contrast for a less busy look
- Number input control now supports 4-direction dragging
- Added helpful text explaining the virtual servo option
- Removed unused legacy number drag direction code
Education Tools Expanding
- Edu Activity Editor now supports lesson types
- Foundation laid for richer, multi-format learning experiences
Small Fixes That Matter
- Prevented crashes from null UI selections
- Fixed serial port cleanup on failure
- Cleaned up unused references and legacy code paths
Summary
This release is all about stability, clarity, and future growth:
- Fewer crashes
- Better debugging
- Faster systems
- Smarter UI
- And groundwork for multi-language learning
ARC Downloads
ARC
FREE- 1 third-party plugin skill per project
- Trial cloud services
- Personal, DIY & education use
- Updated every 6–12 months
Download
ARC
PRO- Use on 2+ PCs simultaneously
- Unlimited robot skills
- Cloud backup & revision history
- Weekly features & bug fixes
- Business use permitted
ARC
RUNTIME- Load & run any ARC project
- Read-only mode
- Unlimited robot skills
- Includes early access fixes & features
- Minimum requirements: Windows 10 or higher, 2 GB RAM, 500 MB free disk space.
- Recommended: Windows 10 or higher, 8 GB RAM, 1 GB free disk space.
- Prices are in USD.
- More about each edition: Download & install guide.
- Latest changes: Release notes.
Compare Editions
| Feature |
ARC
FREE
|
ARC
PRO
|
|---|---|---|
| Get ARC Free | View Plans | |
| Usage | Personal · DIY · Education | Personal · DIY · Education · Business |
| Early access to new features & fixes | — | ✓ |
| Simultaneous microcontroller connections * | 1 | 255 |
| Robot skills * | 20 | Unlimited |
| Skill Store plugins * | 1 | Unlimited |
| Cognitive services usage ** | 10 / day | 6,000 / day |
| Auto-positions gait actions * | 40 | Unlimited |
| Speech recognition phrases * | 10 | Unlimited |
| Camera devices * | 1 | Unlimited |
| Vision resolution | max 320×240 | Unlimited |
| Interface builder * | 2 | Unlimited |
| Cloud project size | — | 128 MB |
| Cloud project revision history | — | ✓ |
| Create Exosphere requests | — | 50 / month |
| Exosphere API access | — | Contact Us |
| Volume license discounts | — | Contact Us |
| Get ARC Free | View Plans |
* Per robot project
** 1,000 per cognitive type: vision recognition, speech recognition, face detection, sentiment, text recognition, emotion detection, azure text to speech
Upgrade to ARC Pro
ARC Pro will give you immediate updates and new features needed to unleash your robot's potential!
....Yes, this!....Great job...and since I cant drop a comment on the skills pages, thank you for the ESP32 and the PCA9685 updates! Especially the ability to daisy chain the 9685!! I'll try to get around to testing later this week.
I know, right?! These updates are pretty wild. There's a new tool we created that generalizes log data to help identify bugs and also evaluate user interaction so the UI keeps progressing. I really still want to move away from Windows, the web UI is the right way but we're still evaluating how to not need a supercomputer to render the pages haha.
The decision not to comment on some content types was changed a while ago because the comment list was growing toooooooo large and was impossible to manage. it now forces certain content types to have their own threads - more threads is easier for ppl to search. the forum gets a ton of views but almost zero posts because ppl don't use forums anymore. it's now a place to search, or point chatgpt at and ask it to search for you haha. commenting on generic contents like this is good - or creating "general" conversation threads is good too.
Excellent work on the updates! Very happy excited to see this kinda progress happening from Synthiam!