Random

The runtime exposes a deterministic random module.

Important Caveat

This is not secret randomness. It is seeded from public execution context, so observers can reproduce it.

Available Functions

random.seed()
random.seed("round-2")
random.getrandbits(k)
random.shuffle(items)
random.randrange(k)
random.randint(a, b)
random.choice(items)
random.choices(items, k=k)

Rule

Call random.seed() before using the module in a transaction.

The base seed is derived from:

• chain_id
• block_num
• block_hash
• __input_hash

If you pass a value to random.seed(...), it is treated as a literal extra salt and resets the sequence for that execution.

Good Uses

• lightweight games
• shuffled ordering with accepted predictability

Bad Uses

• hidden lotteries
• cryptographic secrets
• anything that depends on unpredictability