Vega SDK Release Notes

Rate your experience with the Vega SDK

Vega SDK version 0.21

Vega SDK v0.21 introduces significant changes and improvements. Key highlights include:

1. Vega Virtual Device (VVD): Rebranded from "Simulator," featuring an improved user interface (UI), keyboard controls for Fire TV Stick remote functions, and better error handling.
2. Telemetry framework: Comprehensive documentation across all Vega tools, with default-enabled telemetry and simplified opt-out procedures. Enhanced privacy notices and Visual Studio Code (VS Code) integration.
3. Developer tools: Ubuntu 24 support added, Vega Studio available in VS Code marketplace, and improved error messaging system implemented.
4. Performance analysis: New ESLint Plugin with pre-built performance checks, Perfetto UI integration for system trace analysis, and custom file type editors for data visualization.
5. New performance KPIs: Implemented video/UI frame drop tracking and app event response time measurements, including Input Key Latency for scrolling and consecutive frame drop counts.
6. Developer experience: Improved manifest validation with real-time feedback, better error messaging, and streamlined development workflows.

We have also improved authentication with Login with Amazon flows, addressed multiple video playback and caption-related issues, resolving stream freezes, mid-roll ad transitions, and caption positioning challenges. We significantly improved system stability by fixing critical service registration handling, timer management, and resource conflicts. These improvements provide a more robust and stable development and user experience.

This release requires OS 1.1 (1001010443450) on your Vega Fire TV Stick, which is compatible with the Vega SDK v0.21. You can check your device software version by navigating to My Fire TV > About.

Announcements

Vega private NPM packages moving to public registry

We migrated the Vega NPM packages from our private registry to the public NPM registry, transitioning from the @amzn to @amazon-devices namespace. This change eliminates token requirements and simplifies development.

Key Benefits for the move

• Simplified development: Developers no longer need to configure .npmrc tokens for Vega development.
• Improved library accessibility: Our SDK is more easily accessible through the public registry.
• Streamlined namespaces: While there will be a temporary period of dual namespace use, we plan to sunset @amzn for external use.

Sample reference apps available on Github

Our sample apps have begun moving to Amazon’s Github space for direct download to be accessible without the need for access tokens.

Vega Virtual Device (VVD) enhancements

Vega SDK v0.21 introduces improvements to the Vega Virtual Device (VVD) and Vega CLI (VCLI) with streamlined commands, an improved user experience, an updated Vega Studio extension, new keyboard controls, and improved error handling.

Name and command updates

The Vega Virtual Device identifier is now VirtualDevice, replacing the Simulator identifier across all tools and interfaces. Support for the Simulator identifier ends November 2025. You should start using VirtualDevice before this change takes effect.

KVD user interface updates

We redesigned the KVD interface to provide:

• Clear messaging that registration is optional unless you're using Amazon services.
• Consistent styling (colors, spacing, and typography).
• Helpful tooltips and informational elements for improved usability.

Vega Studio extension updates

• "Simulator" is renamed to Vega Virtual Device in the command palette.
• "Simulator:TV" is renamed to VirtualDevice:Tv in the Devices section.

New keyboard controls

We added keyboard mapping functionality to the Vega Virtual Device, allowing you to control Fire TV Stick remote functions with keyboard shortcuts. See the Vega Virtual Device documentation for details.

Improved error handling

We replaced the generic result codes with detailed error messages when device-related operations fail, helping you diagnose and troubleshoot problems.

Telemetry documentation updates

We made comprehensive updates to our telemetry collection and supporting documentation, providing greater transparency and control over data collection in Vega tools.

Key Updates:

• Detailed breakdown of telemetry collection across all Vega tools, including Vega Studio, Vega CLI, Vega Virtual Device, Vega Performance CLI, and the Vega Appium Driver.
• Simplified opt-out procedures for developers.

Important Changes:

• Telemetry is now enabled by default in the Vega SDK.
• New configuration options available in {$KEPLER_SDK_PATH}/state/kepler-telemetry/config.json.
• Improved privacy notices and data usage explanations.
• Integration with VS Code telemetry settings for Vega Studio users.

For details, see Manage Telemetry in Vega Tools.

This update reflects our commitment to transparency and developer choice in telemetry collection, while improving the Vega development experience.

Vega Web App update

For WebView developers, your must modify your package.json file. For details, see Vega Web App dependency update.

Developer tools

Vega v0.21 introduces the following Vega developer tools improvements:

• Added Ubuntu 24 support to Vega Virtual Device.
• Added Vega Studio to the VS Code marketplace.
• Added ESLint Plugin. ESLint Plugin uses pre-built performance checks in Vega Studio tooling (CLI and UI) to automatically detect common code-level issues, such as FlatList usage, missing splash screens, or console.logs. Checks are categorized as must-have (errors) and good-to-have (warnings). Developers can submit test proofs and confirm to Appstore teams that they’ve passed must-have tests during app submission.
• Added new Performance Monitoring KPIs. This includes implementing video/UI frame drop tracking, and app event response time measurements to better evaluate playback smoothness and interaction responsiveness.
  • 3+ and 5+ Video Consecutive Dropped Fames: Counts instances where the app drops 5 or more consecutive frames during video playback, indicating significant playback disruptions.
  • 5+ Consecutive UI Dropped Frames: Counts instances where the app drops 5 or more consecutive frames during scrolling interactions, causing significant UI stuttering. For example, when vertical or horizontal scrolling.
  • App Event Response Time - Focus: Measures the scheduling latency between the native UI thread and JavaScript thread for focus events (onFocus/onBlur). Scheduling delays over 200ms indicate JavaScript thread congestion, which affects the app's responsiveness.
• Added Input Key Latency (Scrolling) tracking KPI measurement to improve app fluidity assessment.
• Added custom editors for specific file types, enabling developers to visualize data through double-clicking files in the IDE.
• Improved error messaging system to provide actionable, detailed feedback for environment setup issues, enabling developers to independently troubleshoot using CLI and Vega Studio performance tools.
• Improved Vega manifest validation. This real-time validation for Vega manifest.toml files, provides immediate feedback on errors and formatting issues directly in VS Code.
• Integrating Perfetto UI directly within Vega Studio as part of the Performance Extension, enabling one-click access to system trace analyses without additional setup requirements, similar to the existing Chrome Dev Tools integration.

Vega Web App dependency update

If you develop your app with WebView, modify your application package.json file to include the following dependency.

"dependencies": {
    "@amzn/webview": "^3.0.0",
    --------------------
},

To install app dependencies, run the following command.

npm install

For more information, see Set Up your Vega Web App.

Third party libraries

• 3P Library Porting Guidelines: Added a 3P Library porting guideline, providing detailed input for the library developer for adding Vega support to their libraries.

Improvements

• Added a Bug Report tool that gathers diagnostic information about your system, devices, and logs. It saves this information as a file on your computer that you can attach when you submit a support ticket. See Set Up and Use Vega Studio for details.
• Added the following Appium commands: push_file, pull_file, install_app, activate_app, terminate_app, and remove_app. See Appium Commands for descriptions and usage.
• Added Application Not Responding (ARN)-timeout management in debug flows to prevent Lifecycle Manager (LCM) from killing apps during line-by-line native debugging sessions.
• Improved caption window positioning and text alignment border padding, vertical stacking logic, and line adjustment calculations, to prevent text overlap and border sticking.
• Improved Login With Amazon (LWA) experience on TV platforms by improving the consent page display and visual scaling. Users now enjoy better readability and a more accessible authentication experience on their TV screens.
• Fixed authentication failures associated with Login with Amazon (LWA) flows when parental controls are enabled on devices.
• Fixed UI thread hang by resolving broken mutex lock in React Native for Vega Thread Monitor, which caused deadlock issues in Platform Data Manager.
• Fixed app navigation crash by resolving stack navigator animation issues, removing the need to disable animations (animationEnabled: false) as a workaround.
• Fixed TimingModule issue where clearInterval occasionally cleared incorrect timers due to handle reuse in ARNTimer, resolving timer management race conditions and orphaned setInterval instances.
• Fixed UI flickering issue during home tile navigation in the app, providing smooth transitions without visual artifacts.
• Fixed app crash that occurred when enabling subtitles during Video On Demand (VOD) content playback.
• Fixed video freeze after mid-roll ads by resolving Application Not Responding (ANR) issue caused by deadlock during media player deinitialization.
• Fixed video stream freezing issues by eliminating redundant configuration overrides, and corrected track buffer seek logic for proper gap handling during playback.
• Fixed app crash during content playback by adding synchronization to prevent race conditions in caption track management.
• Fixed the ServiceRegistrar connection handling issue by preserving pending connections during failed unbind operations, and implementing timeout management for stale connections, providing proper service recovery.
• Fixed music playback issues by resolving resource management conflict where Map service was incorrectly terminated by LCM, improving coordination between Resource Manager and Lifecycle Manager to prevent premature service termination.
• Fixed green screen artifact during video playback that occurred after upgrading to React Native w3cmedia package version 2.1.80.
• Fixed black screen issue that occurred when powering on TV after switching between apps and switching off, providing correct app state restoration and launcher visibility.
• Fixed app crash that occurred when playing extended HLS content by resolving stability issue
• Fixed caption text clipping issue by removing unnecessary window padding while auto window size calculates for text display.
• Fixed non-functioning media control buttons used in an app.
• Fixed app crash that occurred when playing VOD content while Message Router command was running simultaneously with the enforce-security command.
• Fixed subtitle alignment and missing text issues in apps for caption cues with identical start/end times.

Known issues

• The Performance tools in binary form don't work on the latest Ubuntu OS versions (22, 24).

  Workaround: Reach out to your Amazon contact, or leave a question in the forum to receive a zip file and installer script that lets you run Performance Tools with Python source codes on Ubuntu devices.

• Activity Monitor doesn't display hot functions of Debug variant apps when launching through Vega Studio.

  Workaround: Launch the app through the VLCM command to observe the hot functions:

  Copy code Copied to clipboard.

  vlcm launch-app orpheus://<App URL>
  

• An app may crash during extended video playback (1-2 hours) due to map iterator race conditions.
• React Navigation theme background defaults to white on release builds when using react-navigation core, although debug builds work correctly.
• Apps may experience Low Memory Killer (LMK) termination during ad playback transitions in a non-logged-in state.
• Shaka Player may stall when seeking to the end of a video using right D-pad navigation.
• Using BackHandler.exitApp() followed by a quick app relaunch causes crashes in release builds or Cannot initialize hmrClient twice error in debug mode.
• App may launch without displaying splash screen, affecting user experience during app startup. The root cause is still unknown.
• Focus property hierarchy in JSON RPC response doesn't align with actual focused elements, impacting Appium selector functionality.
• Closed captions intermittently blink and change positions during live TV broadcasts using real-time generated captions, affecting readability.

Last updated: Sep 30, 2025