Mina Protocol is a minimal "succinct blockchain" designed to reduce computational demands for more efficient execution of decentralized applications (DApps). Known as the world's lightest blockchain, Mina's size is engineered to stay constant even as usage expands, maintaining a balance between security and decentralization. The project transitioned from Coda Protocol to Mina in October 2020. For further insights into this project, refer to our comprehensive analysis of Mina Protocol. The Mina network is merely 22 KB in size, in stark contrast to Bitcoin's 300 GB blockchain.

Mina is focused on developing an efficient distributed payment system that allows users to natively verify the platform from the genesis block. The technical whitepaper refers to this as a "succinct blockchain." The protocol employs Zero-Knowledge Succinct Non-Interactive Arguments of Knowledge (zk-SNARKs), a cryptographic proof that allows someone to verify information without disclosing the information itself. Nonetheless, tracing the platform back to its genesis block can be impractical in a large network. To address this, Mina incrementally computes SNARKs that concentrate only on the most recent blocks, enabling end-users to verify the zk-SNARK-compressed proof instead of a block's entire transaction history. At the center of the Mina protocol is MINA, its native currency, which serves as both a utility coin and a medium of exchange.

Mina shares similarities with Bitcoin in terms of its fundamental framework but diverges in its approach to handling transactions. It also adopts the account model used by Ethereum. The primary distinction between Bitcoin and Ethereum lies in their blockchain states: Bitcoin's blockchain maintains a list of unspent coins, whereas Ethereum's state comprises account balances. Mina, in contrast, utilizes a prover—also known as a snarker—functionally analogous to a miner, to ensure that each block accurately reflects the state. Mina adopts the Ouroboros Samasika, a type of Proof of Stake (PoS) mechanism specifically engineered for succinct decentralized networks, as it allows for bootstrapping from a genesis block. Succinct blockchains feature two main functions: verify and update. The verification function addresses aspects such as consensus, blockchain summaries, and blocks, while the update function interacts with consensus mechanisms and chain summaries. In addition to these implementations, the project employs a parallel scan state to enhance transaction processing speed. This optimization is achieved by grouping unproven blocks and delegating the processing tasks to parallel provers.

Mina is focused on revolutionizing the current blockchain landscape where most platforms rely on verifiers, such as miners or stakers, and light clients who act as third parties in transaction verification. Mina adopts a distinct approach by incorporating multiple participants, each responsible for a specific function within the decentralized network. The three primary roles encompass verifiers, block producers, and snarkers. * Verifiers * Verifiers engage with zk-SNARKS, which are responsible for certifying consensus information. Every Mina protocol user qualifies as a verifier, provided their devices can manage a 22 KB chain and endure a few milliseconds of processing time.

Block producers, who function as stakers or miners, earn rewards and transaction fees. Notably, the protocol does not reduce incentives for these block producers. This group of participants enables Mina users to delegate their coins to them. In addition to bundling transactions into blocks, block producers are required to generate SNARKs for a corresponding number of previously committed trades. Failure to do so during block production could result in incomplete blocks and cause other nodes to reject their validity. If a block producer intends to include 10 transactions on the chain, they must also SNARK trades from the start of the queue. They have the option to either produce the SNARK themselves or use those generated by a specialized group known as snarkers. ## Snarkers Snarkers, also referred to as provers, generate zk-SNARKs used for transaction verification. Block producers compensate snarkers from the overall transaction fees they earn by adding new blocks. However, to be eligible for these fees, snarkers must submit bids. It is important to note that a snarker's zk-SNARK must be used in a block, and the block producer who utilizes it is responsible for incentivizing the snarker. This creates an economic environment where multiple snarkers can submit bids linked to the same transaction. Block producers aim for profitability and will select the bid with the lowest fees, thus challenging snarkers to produce cost-effective SNARKs.

The process commences with a user initiating a transaction, after which the trade enters the mempool—a collection of valid but unconfirmed transactions. Subsequently, snarkers take on the task of generating proofs or SNARKs. The process continues with the selection of a block producer (BP) to bundle transactions into a block. It is important to note that a BP selects transactions from the mempool based on potential profitability. The BP then selects a SNARK in accordance with the rules defined by the consensus mechanism. It is noteworthy that a block producer evaluates the bids to select the lowest-priced SNARK. Moreover, the order book for SNARKs is updated with the inclusion of recently added transactions. Next, the SNARKs are incorporated into a block, which is then added to the chain, thereby updating the network. Snarked transactions are subsequently removed from the chain to maintain the protocol's size. Following this, the block producer updates the protocol’s zk-SNARKs. Finally, the new block is permanently integrated into the chain.