blockchain protocol developers

Abstract: Permissionless blockchains use transaction fee mechanisms to allocate the resources that transactions consume, such as execution, data bandwidth, and state creation. Recent blockchain designs explore pricing these resources separately rather than through a single unit. We study this shift on Ethereum, whose roadmap moves in stages from a one-dimensional fee mechanism to a multi-dimensional one. We build a demand model for the three resources, calibrated from Ethereum's 2025 block-capacity increases, and find that state creation is the most price-responsive. We then evaluate both mechanisms at higher block capacity, combining the model with transaction-level metering reconstruction and block-level simulation. Under a one-dimensional mechanism, state creation determines the fee and suppresses execution throughput. Adjusting how state is metered can align resource usage under constant demand, but a single fee cannot track all resources when demand varies, leaving all underutilized. A multi-dimensional mechanism removes this fee coupling, but execution still generates data that must be propagated. Across different allocations between block execution and propagation time, the multi-dimensional mechanism delivers 4--34\% more execution throughput at similarly low congestion, with higher target utilization and state growth near its intended level.

Abstract: The liquidity providers of most typical automated market makers (AMMs) are passive and known to suffer from adverse selection. AMMs traditionally rely on trades executed on them to sync the price with external markets (and a notion of fair value thereof). As a result, when an external fair value moves, arbitrageurs trade on AMMs to pick off their stale quotes. A recent approach termed proprietary automated market makers (propAMMs) emerged as a response in 2024: these on-chain programs instead have their singular operator quote from its own inventory, repricing without a trade via efficiently provided price updates. By 2026, propAMMs accounted for more than half of SOL/USDC volume on Solana. We present the first year-long longitudinal measurement of propAMMs on Solana, Base and Monad, and decode the on-chain logic of the dominant propAMM on Base. We find that two seconds after a fill, propAMMs earn 0.37 bps on Solana and 1.19 bps on Base, while AMMs lose 0.22 and 0.62 bps. We empirically quantify and classify their edge as stemming from four factors: propAMMs continuously reprice rather than waiting for a trade, they charge for the source-dependent risk each counterparty might bring, they avoid cross-venue arbitrage from other on-chain markets (such as other AMMs), and they spoof by filling trades at a worse price than they quote. Finally, we show that on our proxy for retail flow (i.e., fills that arrive when the reference price is not moving) propAMMs collect 0.26 bps on Solana where AMMs collect 2.59 bps, indicating that they offer better prices for short-term uninformed flow.

Abstract: Stateless UTXO-style execution validates transactions using local and referenced data, enabling parallel validation and predictable serialized-size/weight accounting. Multi-step workflows thread state across outputs, and a prepared next-step transaction may become stale if another valid spend confirms first. Explicit state threading therefore shifts consistency maintenance, off-chain tracking, and transaction rebuilding to the protocol boundary, increasing coordination cost and latency. Recursive invariants (RIs), our proposed transaction-level logic and toolchain, address this gap by expressing workflow rules as transaction-level predicates over a transaction's inputs and indexed successor positions referenced by the RI. An accepted transaction realizing such a successor position re-checks the predecessor's RI one step later, carrying the workflow rule forward without shared mutable application state or executable output logic. Thus, multi-step protocol rules preserve validation-time locality and admit explicit cost accounting, while cross-transaction guarantees arise from repeated one-step checking. Not all successor clauses are checkable at validation time, so our small statically typed domain-specific language (DSL) uses three-valued semantics (true, false, unknown) to defer future-dependent obligations until checkable. Co-designed with this DSL, our framework formalizes UTXO validation and ledger extension, identifies the validation-time-evaluable one-step fragment, and proves the deduction system sound w.r.t. the three-valued semantics. We give validation and ledger-extension algorithms for this model. We implement a prototype RI interpreter and benchmarking toolchain for six workloads. Six practice-motivated case studies exhibit roughly linear cumulative validation-cost proxy growth and illustrate staged workflow constraints without preconstructing each successor.

Abstract: The 51% attack remains one of the significant security concern in Proof-of-Work (PoW) blockchains, where increasing hash-power concentration can create a malicious majority-control risk and enable adversarial chain reorganization. This paper proposes a two-layer defense that combines early hash-power monitoring with checkpoint-based mitigation. The first layer monitors mining-power concentration and provides an early warning before the critical majority-control threshold is reached. The second layer uses checkpointing to restrict the depth of accepted chain reorganizations. Monte Carlo simulations are used to evaluate both mechanisms under different attack scenarios. Across 1,000 simulation runs, a 45% warning threshold provided a mean warning-to-critical lead time of 10.531 minutes before the modeled 50% critical threshold was reached. At the selected checkpoint depth of N = 6, approximately 63.68% of simulated reorganization attempts were rejected, while the mean reorganization-depth outcome decreased from 7.948 to 1.634 blocks, representing an approximately 79.4% reduction. The results demonstrate that early detection and checkpoint-based mitigation provide complementary mechanisms for reducing the potential impact of 51% attacks under the evaluated conditions.