nv28 (Fire Horse, 丙午) Network Upgrade Planning

[Tanisha-fil]

Note: All information relating to NV27 has been updated in the Network Updates Repo

This discussion will cover the following for nv28:

1. Scope
2. Timeline
3. Naming of the Upgrade

[Tanisha-fil]

Scope

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FIP/FRC	Link	Status & Progress	Timeline	Summary	Notes
🟢 Export Sector Status	FIP-0112	Accepted	Is feasible to proposed timeline	This FIP is to add a liveness check method to the builtin miner actor to allow for user space fevm contracts to check on the status of filecoin sectors based on sector number.	no major concerns, just finish through FIP lifecycle
🟢 secp256r1 (P-256) P256VERIFY precompile	FIP-0113	Accepted	can be done, just needs FIP Process follow though	This FIP proposes adding a P256VERIFY precompile at Ethereum address; (i.e., 0x0100) to the FEVM	no concerns raised to this FIP
🟢 Add Support for EIP-7939 (CLZ Opcode) in the FEVM	FIP-0114	Accepted	can be done, just needs FIP Process follow though	Add Support for EIP-7939 (CLZ Opcode) in the FEVM	no concerns raised to this FIP
🟢 Premium Percentile Ratio	FIP-0115	Accepted	no concerns raised to this FIP	This adds a FIP for the Premium Percentile Ratio proposal which was described here.	at risk of FIP Process timeline for inclusion
🟤 FIP-0107: Implicit messages in block receipts	FIP-0107	Deferred to next upgrade to NV’29?; Move to implementor call for decision	Misses August deadline	Would allow implicit messages in receipts; deferred due to lack of bandwidth in Lotus & Forest	To be determined on Implementors Call
🟤 Fork Signaling Repurposing	FIP-discussion-1221	Is possible, needs bandwidth to implement	not a driver, possible implementation without an upgrade	Uses the unused 64-bit BlockHeader.ForkSignaling field to signal: miner software ID, network upgrade readiness, actors bundle version, and upgrade epoch offset. Improves network visibility.	To be determined on Implementers Call
🟤 Sealer ID	PR #993	Deferred; to NV29, not in progress	High-risk; deferred	Assigns unique ID to sealers; significant miner-actor change	Needs to be reevaluated if needed
🟤 F3 Calibration Smart Contract Activation	F3-issues-1054	Not in progress, priority is to be determined	Not seen as a priority currently	Enables setting F3 activation date via smart contract on Calibration net for easier testing and resets. Needed for nv28 upgrade testing.	Not included in NV'28, potential for NV' 29

Legend:

• 🟢 Ready for NV28 (no timeline concerns)
• 🟡 Needs review / at risk but possible for NV28
• 🔴 Deferred to nv28 upgrade from nv27
• 🟤 Deferred to nv29 (next upgrade)

[BigLep]

Potentially a fallout action from filecoin-project/FIPs#1224, but the specifics are still being figured out.

[ThatGuyLLC]

Adding here for potential discussion around adding these:
FIP 0113: filecoin-project/FIPs#1228
FIP 0114: filecoin-project/FIPs#1230

[ThatGuyLLC]

To do for me:

1. highlight all the intermediate dates that an EOApril upgrade entails
2. when all included FIPs should be accepted, when code freeze across impls would be, and when the calibration upgrade would be

[ThatGuyLLC]

Final Scope for Nv28 Firehorse:

🟢 Export Sector Status filecoin-project/FIPs#1220
🟢 secp256r1 (P-256) P256VERIFY precompile filecoin-project/FIPs#1228
🟢 Add Support for EIP-7939 (CLZ Opcode) in the FEVM filecoin-project/FIPs#1230 A
🟢 Premium Percentile Ratio filecoin-project/FIPs#1233

[ThatGuyLLC]

Happy to announce that the Filecoin nv28 Fire Horse "丙午" upgrade is complete! 🔥🐎

What does this mean for people using Filecoin?
In simple terms, Filecoin applications can now become easier to use and more reliable. Apps can support familiar authentication methods like Face ID, fingerprints, and hardware security keys instead of forcing users to rely only on seed phrases and browser extensions. Smart contracts can also verify storage conditions directly onchain, opening the door for automatic renewals, storage guarantees, and more transparent service commitments. Combined with improvements to transaction cost predictability, Fire Horse gives builders better tools to create Filecoin applications that feel more practical, trustworthy, and user-friendly.

You can view the upgrade details in the Filecoin community thread and follow the latest chain activity through explorers like Filscan and Beryx.

[Tanisha-fil]

Tentative Nv28 Timeline

Item	Date	Note
Actor code freeze	2026-04-17	This can happen as early as all FIPs becoming accepted. (This means that actor code freeze could happen as early as 2 weeks after the last FIPs in scope enter Last Call, since they’ll stay in Last Call for 2 weeks.) Actor code freeze may need to be after all FIPs are Accepted if more implementation time is needed for the FIPs.
Lotus RC for Calibnet	[week of] 2026-04-20	This happens at least one day after the actor code freeze because the new actor bundle needs to be “packed” into Lotus (docs). It may need to be longer if additional outside-of-actors implementation work is needed.
Calibnet upgrade date	[week of] 2026-04-27	Usually this is a minimum +1 week after Lotus RC.
Final Lotus release	[week of] 2026-05-04	Can happen after a verified successful Calibnet upgrade.
nv28 mainnet upgrade date	[week of] 2026-05-25*	Usually there is a minimum of +2 weeks after Final Lotus release.

[Tanisha-fil]

Name of the Upgrade

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Firehorse "丙午" — High-energy transformation phase, signaling rapid change and forward momentum across the protocol

[Fatman13]

TACO

[TippyFlitsUK]

Big Apple

[decentramike]

Skyline (天际线)

[Qingwarthen]

Fire horse

[ThatGuyLLC]

Poll is closed, Upgrade name is now Fire Horse

[ZenGround0]

We should aim to get this UnNumbered FIP in for the next network upgrade: filecoin-project/FIPs#1220 -- Export Sector Status to EVM callers

[Qingwarthen]

Fire Horse