View Detail Proposal:
https://docs.google.com/document/d/1baZdRrWHzMVfgPjItV7TTaPmRYusg8oB1B5r9qvkUbs/edit?tab=t.0#heading=h.yz9e29yoe69j

Executive Summary

Subscan is the leading high-precision Web3 explorer and essential data infrastructure for the Polkadot, Kusama, and Substrate-based ecosystems. It provides a comprehensive, user-friendly interface for ecosystem participants to track extrinsics, events, transfers, and governance activities. Beyond a visual block explorer, Subscan serves as a critical developer tool, offering the free API plan that powers numerous wallets, DApps, and analytics platforms across the network.

We understand that reviewing comprehensive treasury proposals can be time-consuming. To ensure complete transparency and provide a clear guide for OpenGov voters, we have summarized the entire proposal into the table below.

Past proposals

#151 Subscan | Infrastructure Costs of Subscan for Polkadot & Westend & Rococo Networks

#20 Subscan | Infrastructure Costs of Subscan for Polkadot & Westend & Rococo & Statemint & Rockmine Networks (from July to December 2022)

#1056 Subscan | Infrastructure Costs of Subscan for Polkadot & Westend & Rococo & Statemint & Rockmine Networks (from October 2023 to June 2024)

#1366 Subscan Q3/Q4 2024 Funding Proposal: Basic service fee & Development cost for the Polkadot, Westend, and Rococo Ecosystems）

#1727 Subscan Q4 2024 – Q2 2025 Funding Proposal: Basic Service Fee & Development Cost for the Polkadot and Westend Ecosystems

#1866 [Polkadot] Subscan 2025 Q2-Q4 Funding Proposal: Basic service fee for the Polkadot Relaychain and Polkadot public parachain (AssetHub, BridgeHub, Coretime, Collectives, People)

Infrastructure Settlement (Q3 & Q4 2025)

(Covering the Polkadot Relay Chain + 5 System Parachains: AssetHub, BridgeHub, Coretime, Collectives, People)

1. Service Continuity, Zero-Downtime Commitment, & Billing Precedent (Important Notice)

We would like to clarify to the community why this invoice is submitted after the service period has concluded:

No Service Termination Notice: Prior to and during H2 2025, Subscan did not receive any notice or request from the Community, OpenGov, or the Parity team to suspend or terminate our explorer and indexing services. On the contrary, we continuously received follow-ups and technical communications from Parity staff regarding the upcoming architectural upgrades.

Ecosystem Lifeline: Halting our explorer services would have immediately paralyzed crucial ecosystem infrastructure. Major wallets (Nova, SubWallet), dApps, and OpenGov dashboards (Polkassembly, SubSquare) rely heavily on Subscan's APIs. Shutting down would have caused severe disruptions for end-users and developers alike.

Fronting the Costs (The Post-Paid Model): Despite the exhaustion of previous funding cycles, Subscan acted as a responsible, enterprise-grade B2B provider. Based on a two-year historical precedent of a "post-paid" (settlement after service) model, we fronted all Q3 and Q4 cloud infrastructure expenses out-of-pocket to ensure continuous service.

Identical Pricing: The pricing model used for these invoices is 100% identical to the fee structure approved by the community over the past two years, with absolutely zero unexpected markups.

2. Q3 Invoice Breakdown (July 1 - Sept 30, 2025)

This invoice strictly covers the hard costs of enterprise cloud databases, 24/7 DevOps maintenance, and high-throughput bandwidth. To ensure absolute clarity for the review process, the H2 2025 financial breakdown is calculated precisely by dividing the 6-month service cycle evenly in half.

3. Q4 Invoice Breakdown (Oct 1 - Dec 31, 2025)

Q4 was characterized by high-frequency on-chain activities and multiple runtime upgrades across system parachains. This invoice settles the SLA and maintenance costs that guaranteed a robust data layer during this critical period.

Delivered Results: By honoring these invoices, the Treasury is settling the infrastructure costs that kept the ecosystem running smoothly. We are proud to report that despite massive data indexing demands, Subscan's actual Service Level Agreement (SLA) uptime exceeded 99.5% throughout both Q3 and Q4. We flawlessly executed millions of user queries, developer API calls, and cross-chain events.

AssetHub Migration Special Engineering Settlement (2025)

1. Background: Supporting a Major Architectural Shift

The AssetHub Migration in 2025 was a mandatory architectural upgrade to facilitate the "Asynchronous Backing" era and one of the most complex structural shifts in Polkadot’s history. It required moving critical logic (balances, staking, governance traces) across chains. To ensure zero data corruption, unbroken auditability, and a seamless UI transition, we maintained continuous sync with the Parity team perfectly aligning our explorer compatibility and historical data backfilling with the official roadmap.

2. A Massive Concession: Subscan Absorbs 83% of Development Costs

Throughout Q2-Q4 of 2025, Subscan delivered a massive array of features to the ecosystem, including XCM Engines, UI overhauls, and routine updates. The total engineering cost for all 2025 upgrades amounted to $73,167 (990 hours).

However, Subscan deeply understands the current macroeconomic constraints of the OpenGov Treasury. We want to ensure community funds are strictly focused on sustaining core infrastructure. Therefore, Subscan has voluntarily removed ALL general development, UI upgrades, and non-migration tasks from this invoice.

We are voluntarily absorbing ~$60,639 (approx. 83% of the total development cost) entirely out-of-pocket. This proposal strictly bills only for the 169.5 hours of precise, critical engineering required to safely execute the AssetHub Migration support tasks.

3. Billed Task Breakdown (AssetHub Migration Support ONLY)

(Highly discounted standard Web3 rates: PM/Design @ $70/hr, Engineering/DevOps @ $75/hr)

Conclusion & Our Ecosystem Commitment

By approving this settlement, the Treasury will clear the total amount of $163,727.50 USDT for H2 2025 (Q3 + Q4) core infrastructure services and the AssetHub migration special engineering. This funding not only covers the hard operational costs that kept the ecosystem running smoothly but also pays for the core engineering of a historic architectural upgrade—ensuring the security, seamless continuity, and full auditability of Polkadot's data infrastructure during the complex AssetHub migration.

Our voluntary absorption of over $60,000 in development costs is a direct testament to our core philosophy: in times of macroeconomic challenges within the ecosystem, Subscan chooses to stand firmly with the community. We are not just a service provider; we are deeply committed, long-term builders of Polkadot. We look forward to continuing to provide top-tier underlying infrastructure support for the Asynchronous Backing era and beyond. Thank you to the community for your continued trust in our enterprise-grade infrastructure.