lasking88

Customized Arbitrum optimistic rollup - Go, Solidity. System architect and lead implementer. Customized the Arbitrum Nitro stack into an exchange-specific L2 and own the design of its settlement path end to end. Built the orderbook DEX trading engine and the liquidity vault accounting layer, with notional and margin-utilization caps enforced at order-trigger time. Designed the protocol primitives the exchange UX depends on: gasless transactions, session keys for delegated order signing, and a time-nonce scheme for ordering under high-frequency submission. Extended the account model so native tokens behave as first-class ERC-20, removing wrap/unwrap from the settlement path. Closed a class of value-integrity defects before mainnet and hardened the sequencer against denial-of-service and liveness stalls. Load-tested the chain with a distributed Locust harness, sustaining 3,000+ orders/s with matching; instrumented the entire block-production path with hierarchical timers and CPU profiling to quantify and fix bottlenecks (GC pressure, single-worker serialization, cache misses), and designed a determinism-preserving per-symbol parallel execution model.

Kaia/Klaytn node client - Go. Ported the flat state snapshot subsystem (difflayers, disk layer, journal, generation, range proofs, iterators) and built the snap sync protocol on top of it. New nodes sync from a flat-snapshot download instead of replaying full state, cutting sync time sharply, and state reads are served from the flat path without trie traversal. Reworked on-chain governance vote handling - fixed the epoch-boundary application order that dropped votes cast across consecutive epochs, corrected vote checks for demoted validators, tightened minimum-staking-based committee and proposer qualification, and built the council/validator query API set. Also designed a P2P protocol extension that reconstructs validator staking state without replaying history. Integrated RocksDB as an alternative storage engine (metrics, property APIs, sharded-DB support), and contributed to the design and review of live pruning (KIP-111), which clears stale state on a running node to curb disk growth.

Klaytn Real-Time Chain Data Extraction (chaindatafetcher) Klaytn core - Go, Kafka, MySQL. KAS’s external fetcher could not process chain data fast enough to keep up. Rather than scale the fetcher, I moved extraction into the node itself - emitting data straight to Kafka during transaction execution instead of re-fetching and re-deriving it afterwards. Built the resulting module in Klaytn core, extracting blocks, transactions, internal traces, token transfers, and contract data, with checkpointing and retry. Solved node pressure from internal traces reaching hundreds of MB per block during range fetches with size-based throttling, and isolated tracer failures from block processing so a data-extraction error could no longer turn a valid block into a bad block. Klaytn API Service (KAS) Chain data pipeline - Go, Kinesis/S3, DynamoDB/RDS. Designed and built from scratch the data collection pipeline behind KAS, the managed API service exposing Klaytn chain data to external developers - three collection paths (realtime stream, chain-tip tailing, historical backfill) with Kinesis/S3 loading and checkpoint-based failure recovery. Matured the pipeline - storage migration from DynamoDB to RDS, node connection pooling and HA, internal and reverted transaction handling, automatic KIP-7/17 token detection with metadata collection, and an NFT updater with a background job system. Klaytn Mainnet Launch & Node Operations Klaytn core - Go. Ran launch engineering for the Baobab testnet and Cypress, Klaytn’s public mainnet - genesis configuration, network identifiers, and release packaging. Owned the layer that turns the node into a deployable product - the kcn/kpn/ken binary split with packaging and daemon scripts, the bootnode (kbn), and Klaytn’s own P2P discovery with node-type-aware networking APIs. Developed homi, the network bootstrap tool generating genesis, governance, and reward parameters to stand up Klaytn networks. Built reward and governance verification testers as sole author, used to validate protocol correctness.