Build a key value API that returns the time stamp of insertion when you insert a key.

1. Given the key only, return the value of the latest time stamp.
2. Given a key and time stamp return the value of the nearest time stamp in the past or equal for the key

• Maybe Hash Addressing with Chaining
• Time constantly increments
• Inserts happen in order so data can be stored in order
• This is sort of like commit log or event store/stream

key -> bucket

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|   | -> [ [timestamp, value], , , ]
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|   |
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|   |
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Because data is already sorted we can hash the key, to find the correct bucket. Then perform a binary search to find the value closest to the desired timestamp.