NU7-rc0 Testnet

The first NU7 testnet is live

This is the first NU7 testnet going live. We've built out how we see the consensus changes for NU7 — the most user-facing one is the block time reduction, which you can feel before the quickly approaching NU7 vote.

The feature set below matches what we believe NU7 should be, and how we are voting.

Ephemeral by design. This testnet will last about two weeks. We'll ship a more polished one after that — tell us what you'd like to see.

25s

Block time, down from 75s

2×

Orchard max throughput

−40%

Max sandblast attack vector

<5%

Uncle rate on decentralized testnets

What's in NU7

Speed

3× faster blocks

Block times drop from 75 seconds to 25, so payments confirm sooner. We've shown uncle rate stays sub-5% on decentralized testnets, and it will be even lower on mainnet.

Throughput

Double the TPS

Orchard max throughput doubles, so the shielded pool can carry far more transactions per second.

Action limits

Less sandblasting damage

We implement the Action Limits proposal, lowering the maximum sandblast attack vector by 40%.

ZIP-218

Lower PoW variance

Behind-the-scenes difficulty math is retuned for a more secure result, matching the wall-clock guarantees Zcash had at launch. Currently a component of ZIP-218.

Sustainability

Network Sustainability Mechanism

A long-term savings pool for the network. Block rewards halve every four years, so miners eventually depend on variable tx fees. Our NSM variant collects 60% of tx fees and distributes them to miners after the fourth halving.

Sprout

Delayed Sprout deprecation

Sprout pool deprecation is planned, but we're awaiting the token-holder vote on the date. We make the Sprout pool inactive at a date one year out.

What we left out

We do not include memo bundles, and we are not in favor of their inclusion in NU7.

There is one slated change we excluded: the v6 extensible transaction format. This is due to timeline concerns — the code is not written and the ZIP is not agreed upon. The extensible transaction format also carries short-term ecosystem breakage concerns: it breaks parsers, and we worry about Ledger and Keystone devices putting funds at risk of being unspendable. We're fans of the idea, especially long-term — and users will have to update anyway for the subsequent Tachyon upgrade, which follows soon after.

Join the network

Run a node on the NU7 testnet with the published join script. It downloads a bundle containing the node binaries, network parameters, and bootstrap configuration. You only need curl and bash.

Download the join script

Grab it once from the release.

curl -fsSLO https://github.com/valargroup/kresko/releases/download/v0.1.0/join-nu7-testnet.sh

Observer mode

Sync and follow the chain without mining.

bash join-nu7-testnet.sh \
  --bundle-url https://github.com/valargroup/kresko/releases/download/v0.1.0/nu7-join-bundle.tar.gz

Mining mode

Same as above, plus --mine to mine blocks.

bash join-nu7-testnet.sh \
  --bundle-url https://github.com/valargroup/kresko/releases/download/v0.1.0/nu7-join-bundle.tar.gz --mine

Resources

Explore the chain or point your wallet at a public endpoint.