Due to potential display issues with some charts in format across various devices and platforms, please refer to the detailed information in this Google Document:
https://docs.google.com/document/d/1iAToZZz9U2j56bC6VZ_JtFuBV2FIbegvVUi4tz35C_c/edit?usp=sharing
https://polkadot.polkassembly.io/post/3391
Based on this discussion version, this proposal corrects some typos.
Subscan requests funding from the Polkadot Treasury to support 2025 Q3–Q4 operational maintenance for the following five networks:
As one of the most widely used explorers and indexing services in the Substrate ecosystem, Subscan provides essential, high-availability data infrastructure for developers, validators, governance platforms, wallets, and applications built on Westend. This proposal covers only mandatory maintenance and compatibility work, and does not include any optional enhancements or new feature development.
Cost Reduction / Discount Policy:
Owing to the ongoing infrastructure optimization work that has already demonstrated measurable improvements on our testnet deployments, Subscan is offering a 40% discount for this billing cycle. The total requested amount for Q3-Q4 is USD 21,690, reduced from the original USD 36,150. On average, this corresponds to approximately USD 723 per network per month, with each parachain costing only USD 552.6 per month. This discount is a temporary transitional measure while optimizations continue and will remain in place until the new pricing framework is launched in Q1 2026, benefiting all supported networks.
On Westend’s Transition Toward Paseo:
Subscan is aware that Westend is gradually being replaced by Paseo, and that many ecosystem teams are already transitioning. However:
To ensure a smooth and transparent transition, Subscan invites the community to share their preferred direction under this proposal, including:
Subscan will use the community feedback and discussion outcomes to finalize the future support plan, while ensuring developers and ecosystem participants receive sufficient notice and operational continuity during the transition period.
Over the past several months, Subscan has continued to deliver crucial updates and maintenance work for the Westend ecosystem. Beyond providing stable explorer and indexing services, our team has:
As the default block explorer and indexing layer for Westend, Subscan provides the foundational data required by nearly all ecosystem participants.
Without Subscan, many essential tools would face significant data degradation, and the accessibility of historical and governance data would be severely impacted.
This proposal includes the following mandatory maintenance activities:
Important Notice (Updated Pricing & Testnet Optimization Rollout)：
Due to recent infrastructure optimizations that have already demonstrated measurable improvements on our testnet deployments, Subscan is applying the cost adjustments to testnet billing first, at Subscan’s own expense. We sincerely apologize for any temporary instability during the optimization testing phase.
In recognition of both the disruptions and the proven cost savings, Subscan applied a 40% discount to the original testnet service fees in the previous billing cycle as a transitional measure.
As of January 2026, Subscan has officially published the updated pricing plans, reflecting the optimization progress and delivering more stable, predictable, and cost-efficient service fees for supported networks. Moving forward, Subscan will continue refining these optimizations to further improve long-term sustainability and reduce operational overhead for the ecosystem.
Our maintenance packages are designed to support a wide range of data and operational needs while ensuring stable and efficient system performance. Because our cost structure consists of multiple infrastructure and operational components—such as cloud services, network acceleration, monitoring systems, node providers, and Subscan’s ongoing operations—we continue to use storage consumption as the primary metric for determining service fees.
2025 Pricing Tiers:
a. Basic Plan
b. Advanced Plan
c. Professional Plan
Correlation to Real Costs:
Storage growth scales directly with block production and transaction activity, making it a more stable and predictable metric than raw API traffic. As chain activity evolves, storage becomes the clearest and most consistent indicator of the underlying infrastructure load required to maintain long-term historical data.
Subscan Pricing Baseline (Median-of-Period Methodology)：
Following Subscan’s established treasury billing convention, service fee tiers are determined based on the median storage usage of the requested funding period.
For the 2025 Q3–Q4 cycle, we use the Sep 30, 2025 snapshot as the representative baseline point to reflect the median-of-period storage level and to ensure consistent, predictable billing.
Predictable Billing:
Basing fees on storage reduces the volatility caused by sudden traffic spikes and ensures a more transparent, usage-based cost model for both the community and the treasury.
Our pricing also incorporates the broader operational overhead required to run a production-grade, high-availability data service—such as cloud infrastructure, network acceleration, monitoring systems, node providers, and Subscan’s ongoing engineering and support efforts.
Because these components fluctuate dynamically based on cloud regions, traffic patterns, redundancy requirements, and security considerations, they cannot be broken down into a stable or meaningful line-item list. In addition, some of these details involve sensitive architectural and security-related information that should not be fully disclosed publicly in order to preserve system robustness and reduce attack surface.
For these reasons, Subscan adopts a service-fee-based pricing model, which is consistent with industry practices used by major explorer and indexing providers. Pegging the service fee to storage usage strikes the right balance between:
This model also enables Subscan to invest continuously in optimization and long-term cost reduction—ensuring that infrastructure improvements directly translate into better performance and lower overall fees for the ecosystem over time.
| Network | Actual Usage/GB | Date | Package | Fees/Month | Billing Period | Fees |
| Westend | 623.59 | 30/09/2025 | Advanced+ | 2341 | Q3 & Q4: 01/07/2025-31/12/2025 | 14046 |
| AssetHub-Westend | 292.26 | 30/09/2025 | Basic+ | 1287 | Q3 & Q4: 01/07/2025-31/12/2025 | 7722 |
| Coretime-Westend | 104.06 | 30/09/2025 | Basic | 799 | Q3 & Q4: 01/07/2025-31/12/2025 | 4794 |
| BridgeHub-Westend | 156.92 | 30/09/2025 | Basic | 799 | Q3 & Q4: 01/07/2025-31/12/2025 | 4794 |
| People-Westend | 71.44 | 30/09/2025 | Basic | 799 | Q3 & Q4: 01/07/2025-31/12/2025 | 4794 |
To mitigate long-term storage growth and reduce operational costs—particularly for the Westend relay chain—we are executing several structural optimization initiatives. These include efforts to reduce reliance on GCP and lower total cost of ownership.
Deployment Order & Safety Strategy
To ensure data integrity and service stability during the optimization process, we follow a strict rollout sequence:
Testnet → Kusama & parachains → Polkadot & parachains
We only move to the next stage once the previous stage has been fully validated.
As a result, the cost-reduction timeline follows the same order.
Testing has already begun on the testnet networks, and the resulting cost reductions are reflected in the current billing cycle.
We are segmenting frequently accessed data into high-performance storage tiers while moving older blocks and events into cost-efficient archival layers.
This significantly reduces the cost of maintaining multi-terabyte historical datasets.
Given that XCM events represent a major portion of Westend’s data weight, we are optimizing:
These adjustments reduce long-term index growth without affecting query accuracy.
To optimize long-term infrastructure costs, we are:
These changes directly address one of the largest cost drivers in the current operational model.
As optimization progresses, Subscan expects to introduce more favorable and predictable pricing in Q1 2026, including:
BASIC PLAN
ADVANCED PLAN
2026 Estimated Annual Cost (Updated Pricing + Testnet Annual Discount)
| Network | Plan | Monthly (USD) | Annual Discount (Testnet) | Annual Fee (USD) |
| Westend Relay Chain | Advanced (up to 1 TB) | 1,699 | 40% off | 12,232.80 |
| AssetHub-Westend | Basic (up to 500 GB) | 799 | 40% off | 5,752.80 |
| Coretime-Westend | Basic (up to 500 GB) | 799 | 40% off | 5,752.80 |
| BridgeHub-Westend | Basic (up to 500 GB) | 799 | 40% off | 5,752.80 |
| People-Westend | Basic (up to 500 GB) | 799 | 40% off | 5,752.80 |
| Total | 35,244.00 |
Subscan’s goal is to provide high-quality infrastructure service with stable, predictable, and cost-efficient pricing, along with additional discounts for prepaid customers.
If the community fully transitions away from Westend and no longer requires ongoing support, Subscan plans to sunset Westend services in Q1 2026, with a proper transition process. Any transition-related costs will be subsidized by Subscan.
We also welcome feedback and suggestions from the community regarding the 2026 subscription plan. If there is strong community support for a specific approach or preferred funding structure, Subscan will follow the community’s direction and submit a separate proposal to cover the 2026 maintenance costs accordingly.
Please note that this proposal is strictly for 2025 Q3–Q4 maintenance funding only.
The total requested amount for all 5 networks, including all maintenance, operational overhead, and mandatory compatibility work, is USD 21,690, corresponding to a 40% cost reduction from the original rate. This request will be submitted in USDT.
Conclusion
Subscan respectfully requests USD 21,690 (USDT) from the Polkadot Treasury to cover 2025 Q3–Q4 maintenance for the Westend Relay Chain and the four public parachains (AssetHub, Coretime, BridgeHub, People), ensuring continued high-availability indexing, runtime upgrade compatibility, data consistency, and stable API services required across the ecosystem.
This proposal reflects a temporary 40% discounted rate (reduced from USD 36,150) during our infrastructure optimization rollout, and it includes only essential operational work with no optional enhancements or new feature development.
To support transparent treasury decision-making and long-term planning, we have also included a 2026 cost outlook and subscription pricing framework in this proposal, enabling the community to evaluate expected future costs, discount structures, and potential transition options (including a governance-aligned sunset plan if Westend support is no longer required). Subscan welcomes community feedback on the preferred direction for Westend support and will ensure sufficient notice and service continuity throughout any transiti