LibraryConsensus2015Design paperCorpus record
SpaceMint: A Cryptocurrency Based on Proofs of Space
SpaceMint. Sunoo Park, Albert Kwon, Georg Fuchsbauer, Peter Gaži, Joël Alwen and Krzysztof Pietrzak.
SpaceMint elects a leader from plots of stored data. The quality of the stored answer, not a hash grind at block time, decides who may extend the chain.
A reading of the public paper. Not a copy, not a benchmark, and not a claim about any later network.
A 'green mining' pitch should say whether the scarce object is space, time, or stake, and what the lookup proves.
The five-minute read
The defect
Proof of work burns energy in the moment of the puzzle. A proof of space asks whether the scarce resource can be disk that was filled in advance.
The proposal
SpaceMint elects a leader from plots of stored data. The quality of the stored answer, not a hash grind at block time, decides who may extend the chain.
Initialisation fills the disk. Mining then looks up.
A proof of space still needs a rule against grinding and against replotting attacks the paper discusses.
The bound
The paper is not Chia. Chia is a later construction with a different plot and a time delay.
One action, walked through
- A miner commits to a large table.
- At challenge time they open the entries the challenge names.
- The best opening wins the slot.
- Can the plot be generated on the fly instead of stored?
The argument, unpacked
What the paper is for
A 'green mining' pitch should say whether the scarce object is space, time, or stake, and what the lookup proves.
What happened after
Chia and later proofs of space-time cite this line and then change the plot format. Do not collapse them.
What has to be true
- The paper is not Chia. Chia is a later construction with a different plot and a time delay.
- Stored data can be outsourced. The paper's model of the miner is part of the claim.
- It does not measure a carbon cost.
What happened after the paper
Chia and later proofs of space-time cite this line and then change the plot format. Do not collapse them.
What to check before you use the idea
- What is stored?
- Can the plot be generated on the fly instead of stored?
- How does the leader election use the challenge?
Terms
- Proof of space
- A proof that a large amount of data was stored.
- Plot
- The stored table the challenge queries.
The problem the paper names
Proof of work burns energy in the moment of the puzzle. A proof of space asks whether the scarce resource can be disk that was filled in advance.
What the design proposes
- Initialisation fills the disk. Mining then looks up.
- A proof of space still needs a rule against grinding and against replotting attacks the paper discusses.
- It is not proof of stake.
How the mechanism is specified
- A miner commits to a large table.
- At challenge time they open the entries the challenge names.
- The best opening wins the slot.
What this page does not treat as proven
- The paper is not Chia. Chia is a later construction with a different plot and a time delay.
- Stored data can be outsourced. The paper's model of the miner is part of the claim.
- It does not measure a carbon cost.
Why a venture studio still reads it
A 'green mining' pitch should say whether the scarce object is space, time, or stake, and what the lookup proves.
This is Blockchain Lab's reading of a public design paper. It is not the paper, not a copy of it, and not an offer of tokens, equity, custody or a partnership. Later network behaviour can diverge from the text. Nothing here is investment, legal or technical advice.
Research status: Design paper. Last reviewed: 1 October 2026. This is a reading of a public paper, not investment, legal or security advice.