Context of the Proposal
This proposal focuses on the first phase of QMDB integration, specifically implementing core storage functionality without iterators and prefixes with limited support or non-optimal support. This foundational work will enable future enhancements while maintaining compatibility with existing Substrate systems.
Background Research & Team Credentials
Analysis of QMDB core functionality requirements and possibly functionality will be extended for supporting prefixes and iterators. Research on Substrate storage API compatibility. Team expertise in Rust and Substrate development. Experience in low-level database implementations.
https://github.com/QuantumFusion-network
https://github.com/andor0
https://github.com/dedok
Problem Statement
Current Substrate storage implementation faces several fundamental challenges that this initial integration phase aims to address:
* Current crate ‘sp-trie’ implementation requires optimisation
* Inefficient key-based operations affecting basic transaction processing
* Suboptimal transaction verification process
Key Limitations of QMDB
* Does not support iterators and prefix searches
* Non-limitation, mostly its design of QMDN, requires additional memory (RAM, Disk) for indexing (indexer)
Proposal Objectives & Solutions Objectives
* Integrate QMDB as the proof storage engine within Substrate.
* Enable Merkle Proof-based transaction verification.
* Benchmark QMDB inside our DevNet (https://dev.qfnetwork.xyz).
Milestones, timelines, and Budgets
1. Implement QMDB storage traits
Deliverables — Working prototype integrated with Substrate
Timeframe — 3 weeks
Cost (DOT) — 2000
2. Develop a storage indexing mechanism
Deliverables — In-memory B-Tree or sorted sparse list
Timeframe — 2 weeks
Cost (DOT) — 1500
3. Conduct full system testing
Deliverables — All Substrate tests pass
Timeframe — 1 week
Cost (DOT) — 750
4. Deploy, benchmark and optimise
Deliverables — Live on DevNet with monitoring
Timeframe — 1 week
Cost (DOT) — 750
Risks and Mitigation Risk
Mitigation Strategy QMDB may not be production-ready Extensive DevNet testing before MainNet deployment Substrate’s evolving architecture may cause compatibility issues Freeze the Substrate version until integration is stable Increased resource consumption due to indexers Optimise RAM/disk usage and implement caching mechanisms
Resources Required
1 Senior Rust Developer: Expertise in Substrate and low-level systems
1 Senior Rust Developer: Specializing in database architecture
DevNet Environment: Dedicated nodes for rigorous testing
Success Criteria
Substrate nodes use QMDB for transaction storage
All Substrate and pallet-specific tests pass successfully
Performance benchmarks demonstrate improved transaction processing times
DevNet deployment runs stably with real-time monitoring and alerting
Why Polkadot Network?
Polkadot’s focus on modular and scalable blockchain infrastructure makes it an ideal candidate for advanced storage optimisations like QMDB integration. By enhancing storage efficiency, this proposal aligns with Polkadot’s long-term vision of high-performance, decentralized systems.
Additional References
QMDB Technical Paper
QMDB GitHub Repository