Nakamoto Launch: Testnet and Mainnet Rollout Overview
March 1, 2024
This post was updated on April 4th to add information about the selected 'Instantiation' block.
Hey Stackers, let’s look ahead to the nuts and bolts of the testnet and mainnet rollouts for the Nakamoto upgrade. There are several key steps, each of which brings more features live in a safe, step-by-step process that will give builders and partners time to integrate, test, and test some more.
TL;DR: As shared in January, the Nakamoto upgrade will begin rolling out between April 15 - 29 (Instantiation window) which will kick off a period of at least one month for Signer onboarding. After Signers are onboarded, Nakamoto rules will go live in the Activation window between May 15 - 29, finalizing the launch!
Two-Step Release and Signer Onboarding
Core Developers and Working Groups have regularly engaged with builders and key integration partners as pieces of the codebase are wrapped up and going to audit. This ongoing dialog led to the two-step release process described here, which will afford partners, many of whom are new to Stacks, ample time to register on mainnet, troubleshoot their setups if necessary, and be ready to sign blocks upon Activation. New signers need to fully test their setup on mainnet before they can become active validators.

I know folks may have been expecting the full set of Nakamoto features being released all at once in the April 15-29 launch window, but a two-step release that follows the steps taken on testnet has quickly become the preferred path given how much is happening as part of this upgrade.
Step 1, Step 2: Instantiation & Activation
The rollout will follow this two-step process, each of which is implemented via hard fork. Breaking the Nakamoto release into two forks reduces risk by allowing Core Developers an opportunity before full activation to make any final adjustments or bug fixes as they observe pox-4 in the wild and as Signers come online.

This strategy is the same one being used on the testnet and the rollout of the testnet is already in progress (at Step 1, Instantiation).

  1. Step 1 - Instantiation: The pox-4 contract and the majority of the Nakamoto code are shipped, but Nakamoto rules are inactive. This is so other aspects of the contract can be tested before layering on the complexity that comes with the testnet (and later mainnet) being dependent on it. Importantly, this phase also allows time for Signers to register without the network being dependent on them to sign blocks.
  2. Step 2 - Activation: Nakamoto rules turn active, enabling the full set of Nakamoto features including Signer-based functions, fast blocks, and Bitcoin finality. In other words, ‘the switch is flipped’!

It’s important to note the heaviest lift of any hard fork is historically the sync from genesis. With the two Nakamoto forks, one goal is not to require this, making the upgrade more akin to a push-button software update and much simpler for all node operators.
Visualizing the rollout
Before we dive into the details, let’s look at the high-level timeline.

✅ Pre-Launch Testnet (Instantiated)
Live Now

Live and currently available. Nakamoto rules are inactive, pox-4 is available.
✅ Pre-Launch Testnet (Activated)
Live Now

The Pre-Launch testnet reaches its final state, with Nakamoto rules going live including Signer features, fast blocks, and Bitcoin finality.
✅ Nakamoto Testnet (Instantiated)
Live Now

As Core Devs wrap up on the Pre-Launch testnet, Nakamoto Testnet will be brought online as a more managed service for builders and partners and will continue to be maintained. Signers will have access to this testnet, but with "mock signing" of blocks.
✅ Nakamoto Testnet (Activated)
Activation Window: Mid-April

All Nakamoto consensus rules fully activated, complete Signer features, fast blocks, and finality go Live.
✅ Nakamoto Mainnet (Instantiated)
Instantiation Window: Starts at Bitcoin block 840,360. Currently projected for ~April 22.

Nakamoto upgrade begins rollout to mainnet! Nakamoto rules inactive while Signers onboard.
🟧 Nakamoto Mainnet (Activated)
Activation: August 28

Nakamoto upgrade rollout completes! Signer features, fast blocks, and finality all live. Learn more about final steps here.

Note about sBTC:
Previous updates mentioned targeting a launch of sBTC 2-3 months after Nakamoto Mainnet is live and stable. Once Nakamoto reaches Step 1 (Instantiation) in April, many Core Developers will turn their focus to sBTC and produce a more detailed rollout plan to share.
As the work on Nakamoto has progressed, there have been different versions of testnet, often referred to by their noble gas names like Neon, Argon, etc. However, those distinctions have been more geared toward sprints and projects the core devs have broken down work into. You can still call them that if you like, but going forward, it is simpler to look at the two testnets based on what they offer.

The two testnets are:
This brings us to mainnet. As shared in January, mainnet rollout will begin sometime between April 15 and 29 which is currently roughly aligned with Stacking cycle 82.

Once instantiated (Step 1), a period of at least 2 Stacking cycles will be afforded to Signers and other integration partners to register with pox-4. During this time they will ensure their Signers are ready for the progression to Activation (Step 2) where the network will depend on Signers actively validating blocks.

This means that assuming there are no major bugs or issues, full Nakamoto features will activate in mid to late May with some of that depending on how quickly Signers are onboarded. The BD Working Group has noted that they expect 20+ Signers to be ready for mainnet launch, so we have every reason to believe this rollout to mainnet will be smooth on this front and we know the lineup features some of the industry’s infrastructure leaders.
A Deeper Dive On What’s Done and In Flight
Now obviously for this post, I have simplified things to make it easier to understand fairly quickly. However, there are a number of key codebases and components that make everything work. For the more technical folks, I want to highlight the growing pile of completed components here as well as give you a window into the current work Core Devs are grinding on to bring Nakamoto to life in a way we’re all proud of.
  • All boot contracts including the pox-4, signers contracts are ready
  • Signer binary is ready and is being tested
  • All core Nakamoto consensus rules are done
  • Block Validation and Block Proposal logic is done
  • DKG is done
  • Stackerdb is done
  • Tenure-extension logic is done and being tested
  • Mutation Testing is LIVE for all PRs on next and develop
  • Fuzzer is running against the stacks node
Important Dates:

March 11: This is the date the Pre-Launch testnet makes the jump to Nakamoto activation. Go build with the benefit of accelerated cycles and help if you need it.

March 25: This is the date the Nakamoto Testnet will be introduced. Signers are encouraged to join this testnet and prepare for the mainnet release. Connect w/sBTC experts to learn more.
Everyone else:

March 9: Voting for Nakamoto closes! Be sure to vote!
Be ready for the Naka•moment
We recently released a hub for all things Nakamoto to make resources easy to find. On the page, you can find key materials and sections built for everyone from Developers to Exchanges on how you can get started today.
Also linked on that page, you will find the list of 30+ launch events, hackathons, meetups, and other ways you can join the community in celebrating Nakamoto.