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2. The 64-Bit Float Trap: IEEE 754 and Integer Truncation

In the official JSON specification, numbers are arbitrarily sized decimals. However, JavaScript parses all JSON numbers as IEEE 754 double-precision floating-point values:

Number.MAX_SAFE_INTEGER = 9007199254740991; // 2^53 - 1
JSON.parse('{"id": 9007199254740999}'); // yields {"id": 9007199254741000} (CORRUPTED!)

When dealing with 64-bit database identifiers (Twitter Snowflake IDs, database primary keys), always serialize identifiers as strings to prevent silent numeric corruption.

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