FIP-101: Fractal Standard Indexing Service (Draft)
Status: Draft
FIP Number: 101
Title: Fractal Standard Data Indexing Service
Author: UniSat Team
Created: 2025-12-09
Type: Standard Proposal (Consensus Layer)
License: BSD-2-Clause
Abstract
This proposal introduces the Fractal Standardized Data Indexing Service, aiming to introduce a set of standardized data indexing services for Fractal Bitcoin that are maintained by core contributors, open-source, and permissionless to join and operate, while integrating them into the Fractal block reward system. By reallocating the block reward proportions and introducing a non-custodial staking mechanism based on Taproot scripting, this ensures the long-term stability and sustainability of the indexing service.
Abstract
This proposal introduces the Fractal Standardized Data Indexing Service, aiming to introduce a set of standardized data indexing services for Fractal Bitcoin that are maintained by core contributors, open-source, and permissionless to join and operate, while integrating them into the Fractal block reward system. By reallocating the block reward proportions and introducing a non-custodial staking mechanism based on Taproot scripting, this ensures the long-term stability and sustainability of the indexing service.
Motivation
The current Fractal ecosystem faces prominent issues in data indexing:
Lack of Standardization for High-Performance Indexing
Currently, the community has various indexing solutions, including both commercial and open-source ones, but:
Protocol parsing methods and output structures are inconsistent
Maintenance costs for each are high
The community struggles to form consensus on standard interfaces and data formats
This results in significant uncertainty and high adaptation costs in practical application development on the Fractal network.
The Optimal Timing to Introduce Standardized Indexing
Over the past two quarters, the core contributor UniSat Team has conducted a series of ongoing refactorings on their maintained commercial indexer, enabling the system to gradually achieve the following features:
Memory usage reduced by approximately 80%, achieving a lightweight architecture
Initial synchronization can be completed within 24 hours (much faster than some existing open-source solutions in the community)
Significantly lower hardware requirements, greatly reducing the operational threshold
The system's maturity is now sufficient to support a fully open, community-oriented standardized indexing service.
Urgency for Standardization
The protocol layer may fragment due to inconsistencies in software implementations and parsing methods
Developers would need to manually maintain parsing logic across multiple protocols, increasing error probability and hindering the formation of unified development experiences and ecosystem foundations
Therefore, launching a standardized indexing service has become a necessary step for the continued expansion and order maintenance of the Fractal ecosystem.
Specification
Indexing Service Overview
The Fractal Standardized Data Indexing Service has the following features:
Fully Open-Source: Hosted in the official Fractal GitHub repository, maintained in the same manner as Fractal node codebase
Fully Permissionless: Anyone can run the indexer without needing approval
Modular and Extensible: Core indexing engine + protocol parsers + data storage layer
Unified Parsing and Output Structure: Ensuring consistent data presentation for different protocols in the ecosystem
This indexing service will continuously support various protocols within the Fractal ecosystem, including but not limited to:
Inscription-type protocols
Token-type protocols
Custom on-chain metadata protocols
Extensions for parsing future new protocols
The indexer will output parsed results in a standardized data structure, providing developers with a consistent and stable data foundation. In the future, this indexer can also serve as the basis for providing high-performance indexing services on the Bitcoin mainnet.
Tokenomics Adjustment (Block Reward Allocation)
Current Block Reward Distribution:
Merged Mining: 1
Permissionless Mining: 2
Proposed New Distribution:
Component
New Block Allocation
Merged Mining
1
Permissionless Mining
1
Data Indexing
1
The total supply and producing rate remain unchanged; only the allocation structure is adjusted.
The 1:1:1 allocation structure is adopted because, from the perspective of Fractal's network structure, merged mining (security), permissionless mining (autonomous participation), and indexing service (data availability) constitute the three core pillars for the network's long-term sustainable operation. As infrastructure for ecosystem operation, the indexing service's availability and stability are of the same level of importance as network security, and thus should receive relatively equal economic incentives as miners.
Staking
To ensure long-term robustness of the indexing service, this proposal introduces a non-custodial staking mechanism based on Taproot scripting:
General users can stake FB to a specific indexing service instance
Block Rewards are distributed proportionally based on staking shares
Operators can charge a certain service fee
All staked assets remain under user private key control via Taproot paths
Users can withdraw at any time, independent of operator actions
This mechanism is fully compatible with the verified model in FB Farming and can be directly reused.
Rationale
General Justification
A unified indexing standard can resolve protocol parsing fragmentation issues
Integrating indexing into block reward allocation can form long-term stable ecosystem infrastructure
Lightweight mechanisms reduce community operation costs, making the indexing system more decentralized
Non-custodial staking ensures fund security without introducing centralization risks
Technically, it maintains minimal intrusion to the existing chain structure
Non-Goals
This FIP does not modify:
Block size or main block structure logic
UTXO model
Scripting language
Difficulty, PoW, or core anti-attack mechanisms
Total block reward supply, issuance rate, halving mechanism/timing
This FIP does not involve:
Standardization of frontend APIs or SDKs
Specific protocols to support or their rule definitions
Application-layer data format specifications
This proposal focuses solely on chain-level incentive mechanisms + standardization of the indexing service's foundational architecture.
Activation
The activation process will include two phases:
Phase 1: Node-Level Support
New versions of Fractal Node will include built-in logic for indexing allocation handling
Once nodes are widely upgraded, an observation period will begin
Phase 2: Determining Activation Height
Observe based on network-wide node upgrade status and announce the activation height
Execute the new block reward allocation starting from this height
The activation height will be announced in advance with at least 30 days reserved for unupgraded nodes to upgrade
This process is similar to BIP-9 / BIP-8 versioned activation models but better suited to Fractal's governance structure.
Security & Backward Compatibility
This proposal does not modify FB total supply, difficulty algorithm, or block structure
After the new activation height, non-block-producing nodes do not need to upgrade. Only block-producing nodes require additional constraint rules
Delayed Reward Release: Indexing-related rewards are released with at least 7-day delay (approximately 20,000 blocks at least)
Offline Suspension of Allocation: If an indexing node is offline for more than N blocks or fails to produce valid indexing results, its reward allocation is automatically suspended;
Users can withdraw stakes at any time and migrate to other nodes
This proposal does not introduce slashing; staked assets are always controlled by users
The Taproot non-custodial design of staking scripts ensures that indexing service providers cannot access user assets
Reference Implementation
The open-source implementation will include:
Core Indexing Processing Engine
Pluggable Protocol Parsers
Data Storage Layer
RPC Query Interface
Standard Coinbase Output Templates
Taproot Staking Script Templates
All components will be publicly maintained and versioned on GitHub.
UniSat Team
2025-12-09
Last updated