Learn / What is Subtensor?

What is Subtensor?

Subtensor is the blockchain layer of the Bittensor network. It's the on-chain component that records state, processes transactions, and coordinates the incentive mechanism.

Bittensor's Blockchain Layer

Subtensor is built on Substrate, the same framework that powers Polkadot. This gives it:

  • Forkless upgrades. The runtime can be upgraded without hard forks
  • Queryable metadata. The chain describes its own interface
  • Modular pallets. Functionality organized into discrete modules

What Subtensor Handles

TAO delegation from coldkeys to hotkeys

Registration

Neurons joining subnets

Consensus Results

Weights from validators scoring miners

TAO rewards distributed each epoch

What Subtensor Stores

Some data is stored on-chain (queryable anytime). Other values are computed at runtime during epoch processing and not stored directly.

Stored On-Chain

  • Balances and stakes
  • Weight matrices from validators
  • Neuron UIDs and permits
  • Subnet configurations

Computed at Runtime

  • Ranks, trust, consensus
  • Incentive and dividend splits
  • Emission amounts per neuron
  • Yuma consensus calculations
Key Distinction

You can query storage directly at any time. Computed values like ranks, incentive, and dividends are calculated during epoch processing and written to storage, where they persist until the next epoch overwrites them. To access values from previous epochs, you need a historical/archive node or an indexer API.

Learn More About Bittensor

This documentation focuses on Subtensor specifically. For broader Bittensor topics: