Rakan
Al-Hneiti

Core contributor to Citrea, a ZK-rollup bringing EVM execution to Bitcoin. As a Senior engineer, took part in the development of critical rollup infrastructure within a 5-person core team, working on both application layer (sequencer, full node, batch prover, light client) and framework layer (forked Sovereign SDK to implement custom rollup features while maintaining core framework updates).

Key contributions:

• Refactored core components (sequencer, full node, batch prover) with improved async patterns and task cancellation, solving critical RocksDB performance bottlenecks
• Designed and implemented fork manager, commitment service (configurable by diff size/block count), and rollback/pruning mechanisms for chain state management
• Built production infrastructure: metrics collection with Grafana dashboards, database migrations, retry mechanisms with exponential backoff for DA layer integration, RPC methods, and structured logging
• Contributed to proof generation/verification pipeline and transaction chunking implementation for the ZK circuit layer

Led a team of 5 engineers building Enjin's blockchain infrastructure: Efinity parachain (Polkadot), then Enjin Relaychain and Matrixchain (parachains) for gaming NFT ecosystem with ERC-1155-compatible multi-token support.

Key contributions:

• Designed and implemented in-house Substrate pallets: multi-tokens (ERC-1155), collator-staking, pools, fuel tanks, claims, vesting registrar, and XCM integration for cross-chain asset transfers
• Led technical coordination between engineering team and management for feature prioritization, maintained block production and relaychain-parachain sync, executed runtime upgrades with complex chain state migrations
• Built infrastructure for production reliability: implemented Buildbot CI pipeline with E2E testing, coordinated deployment processes with engineering management to ensure smooth releases
• Navigated rapidly evolving Substrate/Cumulus/Polkadot ecosystem, maintaining compatibility across frequent upstream changes and integrating XCM despite limited documentation at the time

Repository: N/A (Closed source) • enjin.io

Core contributor to Substrate blockchain framework as part of the client team, focusing on async/await refactoring and remote signing infrastructure.

Key contributions:

• Refactored keystore infrastructure and authority-discovery subsystem to async/await patterns, improving performance and code maintainability
• Implemented offchain signing capability and remote keystore support, enabling secure key management for validators and node operators
• Integrated remote signing across consensus components (BABE VRF signing, GRANDPA message signing, Aura key validation)
• Refactored runtime public key types (AppKey, RuntimeAppPublic, CryptoTypePublicPair) for better type safety and API ergonomics

Repository: substrate, polkadot

Led development of Raiden Network, an Ethereum Layer 2 scaling solution using state channel and payment channel technology for fast, low-cost off-chain transactions.

Key contributions:

• Led protocol development and implementation of core Raiden Network features in Python
• Designed and developed smart contracts in Solidity for on-chain settlement and dispute resolution
• Architected payment channel state machine and message protocol for off-chain transaction routing
• Built production-grade infrastructure for network reliability, monitoring, and testing

Repository: raiden-network/raiden

Part of the infrastructure team, build system and tooling division, responsible for improving and maintaining Python & Go libraries that microservice developers used in their microservices. Libraries ranged from event/RPC abstraction on top of RabbitMQ to metrics, HTTP, data encoding among others.

Developed a cloud-based backend that builds Big Data infrastructures and Data Pipelines. The system provides RESTful API endpoints to be able to tailor the required Big Data infrastructure configurations and uses cloud provisioning tools such as SaltStack, Puppet to launch and configure AWS or OpenStack cloud that can be used for Big Data processing.

As part of Souq's Platform Team, my role was to design and develop tools to be used by developers within the organization and to tackle issues with the core platform which prevented horizontal and vertical scalability.

Design & Implementation of all backend architecture of Web Portals and Services. At one of N2V's startups named StartAppz, led a team of developers to design and develop systems that expose RESTful APIs used by mobile applications for high profile clients in the Middle East. The backend was based on LAMP stack in addition to MongoDB, Solr, ElasticSearch.

Developing and maintaining high-scale platforms such as Maktoob News, Maktoob Blogs and Maktoob.com (Homepage), which were handling around 1-2 million unique visitors a day. After Yahoo! acquired Maktoob group, my role at Yahoo! consisted of maintaining legacy Maktoob platforms in addition to working with Yahoo's global teams to transition Maktoob's platforms to the Yahoo stacks and platforms. In addition to working with those teams on resolving BIDI issues and various RTL and Arabic-language related issues.