Protocol changes
Bittensor’s behavior is set by the Subtensor chain runtime. When that runtime changes — through a merged pull request, a runtime upgrade, an economic-parameter adjustment, or a governance proposal — your stake, your subnet, and your validator can behave differently overnight.
This section explains those changes in plain language, so you don’t have to read the source diff to know what’s different and why it matters to you.
What you’ll find on each page
Section titled “What you’ll find on each page”Every protocol-change page is structured the same way:
- Status strip at the top — when the change went live, on which network (testnet / mainnet), and a link to the source pull request.
- What changed — the mechanic, formula, or parameter, with before-and-after.
- Why it matters — concrete impact on subnet owners, validators, and stakers.
- Source provenance — the exact Subtensor PR(s) and the code locations that implement the change, so you can verify.
- Cross-references — other docs pages whose framing the change affects.
If a page describes something that is not yet on mainnet, the status strip will say so. Don’t make production decisions from a page marked pending.
When to come here
Section titled “When to come here”- A subnet’s emission, registration cost, or staking yield changed and you want to know why.
- A community thread mentions a Subtensor PR number and you want a sane summary.
- You’re modeling a subnet’s economics and need to know which formula the chain is using right now.
- You’re a validator setting weights and a recent change altered what your weights do.
Pages in this section
Section titled “Pages in this section”Browse the sidebar for current entries. Each page is dated; if Last reviewed is older than the change you care about, open a docs issue and we’ll refresh it.