Sentinel Cover

Sentinel: SDK for Defold

This is an open-source project. It is not affiliated with is an error tracking system. It can track errors and performance issues in any language, framework, and library.

This Defold extension, Sentinel, implements error tracking for your Lua code. Also, it can inject JavaScript SDK to track HTML5 errors if you need that. is a paid system, but it has a free plan for developers to track up to 5,000 errors per month. To the point, it was enough to track down all Lua errors in Puffy Cat during a test period and release a pretty polished game.

Supported Platforms

Platform Status
Lua (all platforms) Supported ✅
Browser (HTML5) Loads JavaScript SDK to track non-Lua errors ☑️
iOS, Android, Windows, macOS, Linux, Switch Not Implemented ❌

Installation & Usage

You can use Sentinel in your own project by adding this project as a Defold library dependency.

Open your game.project file and in the dependencies field under project add the ZIP file of a specific release.


local sentry = require("sentinel.sentry")

function init(self)
        dsn = "YOUR_DSN_URL",
        tags = {
            ["example_tag"] = "Example Tag Data",
        extra = {
            ["example_extra"] = "Example Extra Data",
        release = sys.get_config("sentinel.sentry_release")

Breadcrumbs, Capturing Messages

--- Add breadcrumbs, add tags, extras, and capture messages:
        category = "log",
        message = "Test breadcrumb message"

sentry.config.tags["my_info"] = "Amount of gold"
sentry.config.tags["frametime"] = 100

        message = "Test message",
        level = "info",
        extra = {
            example_extra_2 = "Hello!"

The game.project Settings:

sentry_dsn_html5 = YOUR_DSN_URL_FROM_SENTRY_IO
sentry_release = [email protected]

Setting the sentinel.sentry_dsn_html5 option initializes Sentry JavaScript SDK in the HTML5 template (take a look at how it’s done).

GameAnalytics Compatibility

Only one sys.set_error_handler callback can be set. To track Lua errors both in GameAnalytics and Sentinel, use the option:

    -- ... your config ...
    gameanalytics = true


Artsiom Trubchyk (@aglitchman) is the current Sentinel owner within Indiesoft and is responsible for the open source repository.

This project uses the source code of rxi’s JSON.

Queen’s Guard image is by Chanut is Industries.


MIT license.


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