How do I catch this when it only happens for some players?

Capture it automatically from the player's device with the full stack trace, the device and OS, the build, and a breadcrumb trail of what they did. That turns a vague complaint into a specific, reproducible issue you can fix without owning the hardware it happens on.

How to Fix Construct 3 Array AsJSON Losing Precision on Large Integers

Q: What causes Construct 3 array AsJSON losing precision on large integers?

JavaScript numbers are IEEE-754 doubles, so integers beyond 2^53 lose precision when an array is serialized to JSON and read back, corrupting big IDs or currency values.

Quick answer: Store integers that can exceed 2^53 (large IDs, currency, timestamps in nanoseconds) as strings in the array so they survive the JSON round-trip exactly.

Construct 3 numbers are doubles. Save a value above 2^53 and AsJSON rounds it on the way back, corrupting the save. Store big numbers as strings to keep them exact.

How to fix it

1. Know the 2^53 limit

Integers larger than 9007199254740992 cannot be represented exactly as doubles. Through AsJSON and JSON parsing they get rounded, silently changing the value.

2. Store big numbers as strings

Keep large IDs, soft-currency totals, or high-resolution timestamps as string values in the array. Strings round-trip through JSON without any precision loss.

3. Convert at the edges only

Parse the string back to a number only when you must do math, and keep the canonical saved form as a string to avoid reintroducing rounding.

Catching the ones you can't reproduce

The hardest version of this to fix is the one you can't reproduce — it only happens on a player's hardware, OS, driver, or save state, under conditions that simply aren't present on your machine. A report that says “it crashed” or “it froze” gives you nothing to act on, so the bug survives release after release while quietly costing you players.

Automatic error capture closes that gap. Each failure arrives with its full stack trace, the device and OS, the build number, and a breadcrumb trail of what the player did right before it broke, so even a failure you have never seen becomes a specific, reproducible issue. Fold identical failures into one signature ranked by how many players each hits, and your worklist sorts itself worst-first instead of arriving as a stream of vague complaints.

This is where a tool like Bugnet earns its place. Its SDK captures every Construct 3 error automatically with the full stack trace plus device, OS, memory, build, and game-state context, folds duplicates into one grouped issue with an occurrence count, and ties each to the build it first appeared on — so you fix the problem that hurts the most players first and confirm it is gone when its signature disappears from the next release.

The errors you never hear about are the ones quietly costing you players. Visibility turns them into a worklist.