Proposal: ink! Alliance Bounty - Preparing for Polkadot Hub

Bounty: https://polkadot.polkassembly.io/bounty/70
Proponent: ink! Alliance. 147N9zPaDutDVthgnLKay7MjZ223FZMD9iq7zuMqDU19SgqU
Date: September 2025
Requested DOT: 261,137 DOT $1,112,000 (based on EMA7 rate by Subscan on 09-23-25)
Curator Fee: 0$. No curation fees. Curation and management of this bounty will be submitted to the bounty itself on a per-task or per-project basis.
Curators: Michael Müller, Parity Technologies, Polytope Labs, R0GUE, Virto.
Short Description: The purpose of this bounty is to ensure ink! remains the flagship native Rust smart contract language of Polkadot by finalizing, auditing, and launching ink! v6 on PolkaVM, while continuously maintaining, and optimizing the ecosystem. The bounty will cover currently identified tasks such as audit remediation, ink! v6 release, tooling improvements, tutorials, and hackathons, while also providing flexibility to fund future needs like ongoing SDK compatibility, performance optimization, and readiness for the Hub launch. ink! will be the first competitive smart contract language on PolkVM.
Full Proposal Document: https://docs.google.com/document/d/1Brl7EJEjQ02sV8yy9PhWAuI-2_YkGrSaAs8t-obgEGE/edit?tab=t.0

1. ink! Alliance Executive Summary & Update

Since the initial proposal, the ink! Alliance extended the funds to twelve months, twice the planned six, delivering on its objectives, and much more. This was achieved by deliberately keeping the developer count lower, a decision made in light of PolkaVM and Polkadot Hub delays outside the Alliance’s control. Rather than scale prematurely, resources were focused on high-impact work, ensuring steady progress and extending the lifetime of available funds. This approach has been validated by OG Tracker, with a full outline of deliverables provided below. A full budget breakdown can be found here.

1.1. From Proposal to Bounty in Preparation for Polkadot Hub

With Polkadot Hub nearing launch, the Alliance proposes restructuring under a bounty model. This ensures both accountability and the flexibility needed to align ink!’s development, education, and community support with the Hub’s evolving needs.

As the only language presently capable of bringing PolkaVM to market in December, ink! requires a funding model that secures launch readiness while remaining adaptable in preparation for the Hub's launch and ongoing support.

This bounty goes beyond hitting the launch milestone. Rust’s safety and performance, combined with ink!’s deep Polkadot SDK integration, uniquely position it to highlight Polkadot’s strengths. By showcasing cross-chain dApps, boosting performance, and refining tooling, ink! will be both launch-ready and the clear choice for next-generation smart contracts on Polkadot.

What makes ink! different and why it matters now

• XCM-first: Native SDK integration makes cross-chain calls easier and safer, lowering time-to-mainnet for multi-chain dApps and directly showcasing Polkadot’s unique interoperability.
• Performance: Smaller binaries, lower gas, and better ergonomics unlock advanced use-cases that are impractical in other languages.
• Rust talent pool: With ~5.1M+ Rust developers worldwide, growing enterprise adoption, and proven success of Rust-based smart contract ecosystems elsewhere, ink! massively expands the Hub’s ability to attract builders.
• Rich Rust ecosystem: ink! inherits Rust’s vast library of crates, tooling, and frameworks, giving developers immediate access to ready-to-use components.
• Compiler-level security: Rust prevents entire classes of bugs at compile time, reducing vulnerabilities and increasing safety for on-chain code.
• Developer confidence: The strict type and ownership model makes common pitfalls impossible, raising confidence in shipping production-ready contracts faster.

1.2. Achievements

In the last funding cycle (Oct 2024 - Sept 2025 inclusive), the ink! Alliance delivered significant advancement to the ecosystem’s technical capabilities, including:

ink! v5

• Released ink! v5.1 with new features such as XCM support.
• Completed a full and highly successful security audit of v5 by SRLabs and Parity Security.
• Maintaining ink! v5, running on pallet-contracts/WebAssembly.
• Publishing new minor releases for v5 and fixing community reported bugs.

ink! v6

• Full migration from pallet-contracts/Wasm to pallet-revive/PolkaVM.
• Solidity ABI support, enabling ink!/Solidity interoperability. Developers can now also use existing Solidity tooling directly with ink! contracts, while still benefiting from PolkaVM’s performance and security. This enables the usage of MetaMask and Solidity frontend libraries (like ethers.js) with ink! contracts.
• Extensive testing pipeline for PolkaVM & pallet-revive, uncovering upstream bugs.
• ink! tooling support (cargo-contract, Contracts UI, etc.) upgraded for PolkaVM readiness.

Notably, Solidity ABI compatibility was not part of the original scope and represents additional value delivered to the ecosystem.

Education & Onboarding

• Website & Docs Overhaul: The Alliance worked closely with Flez and Niftesty to rebuild the entire use.ink site, refreshed documentation, and redesigned learning materials, dramatically improving the onboarding experience for new developers.
• Active Social Presence: ink!’s voice across @ink_lang and community channels continues to grow, driving awareness, showcasing success stories, and making ink! the recognized Polkadot-native contract language.
• Sub0 Reset (Oct ’24): The team showcased novel cross-chain contract functionality with ink! and messaging, showing developers how to compose services across parachains.
• Hackathon at Sub0 Reset (Oct ’24): The Alliance also ran the ink! v5 dApp track at the WebZero Blockspace, creating hands-on challenges to onboard builders and collect feedback for v6. During the competition the team reviewed and provided feedback on 43 challenge submissions.
• Hackathon at Web3 Summit (Jul ‘25): In collaboration with the ink!ubator, ink! v6 on PolkaVM was in developers’ hands for the first time. Developers successfully built, tested, and deployed contracts on PAsset Hub. This milestone proved ink! is approaching production readiness and highlighted the need for smooth testnet cycles and integrated tooling. Read the full story here.
• Community Workshops & Tutorials: Delivered two tutorials for the Encode Club x Polkadot ink! Bootcamp, covering Cross-Contract Calls on ink! and Creating Multi-Chain Contracts with ink!, in addition to a DAO Workshop & AMA in collaboration with Edgeware.
• Polkadot Blockchain Academy Bali (Sept ‘25): The Alliance sent a tutor to train the latest wave of Polkadot developers in ink!, ensuring they graduated ready to build secure, performant, and composable contracts for Polkadot Hub and beyond.
• ink! article published in CoinsBench (Sept ‘25): ink! speaks Solidity on PolkaVM

Since the last funding round, the ink! Alliance has consolidated ecosystem contributions into GitHub tracking issues, providing greater transparency and coordination across projects.

Beyond its original mandate, the Alliance has made significant contributions to PolkaVM¹, pallet-revive², and alloy-rs³ strengthening the broader Polkadot SDK tooling landscape. Today, ink! operates what is likely the most extensive testing pipeline for both components, surfacing upstream issues.

¹ [TRACKING] Contributions to polkavm
² [TRACKING] Contributions to pallet_revive
³ [TRACKING] Contributions to alloy-rs

Over the next six months, the Alliance will finalize ink! v6 with optimizations, finalise audit remediations, and accelerate adoption through education and developer engagement, ensuring Polkadot Hub launches with a mature, production-ready Rust smart contract language. Beyond the Hub launch window, the proposed bounty provides for continued maintenance, improvements, and ecosystem growth over the subsequent six months, ensuring ink! remains reliable, well-supported, and a cornerstone of Polkadot’s smart contract strategy.

2. ink! High Level Technical Status Summary

2.1. Current Status

• ink! v5: Audited, maintained with bug fixes and minor releases.
• ink! v6: Pre-release state, feature-complete for pallet-revive/PolkaVM.
• Toolchain: cargo-contract and Contracts UI updated for RISC-V execution.
  • DRink!: Core functionality is now native in ink!’s e2e testing framework and will be deprecated going forward.
• Docs & Tutorials: Updated for new architecture, with community-driven improvements.
• Ecosystem: ink! is supported by numerous parachains including Phala, Peaq, Astar, Kreivo, and Polkadot Hub in the imminent future.

ink! v6 has not yet published v6 (only pre-releases) for the following reasons:

1. Work on pallet-revive is still ongoing, requiring additional development in ink! v6 following those changes.
2. ink! v6 has not yet been audited.

​​3. Context of the Proposal

Polkadot is at a decisive moment. The Hub is preparing for its most important launch to date: a dual smart contract platform that will support both EVM and PVM contracts. This strategy balances short-term traction with long-term innovation. On one side, Revm integration allows Solidity developers to deploy unchanged contracts with familiar tooling, unlocking immediate opportunities to onboard top-tier Ethereum dApps and infrastructure providers. On the other, PolkaVM is Polkadot’s forward-looking, RISC-V powered engine for high-performance smart contracts and the foundation for next-generation applications.

This dual path is pragmatic, but also revealing. While EVM compatibility creates a fast lane for existing Web3 developer adoption, it is limited by the constraints of Solidity and the Ethereum model. PolkaVM is the future: faster execution, and the foundation for JAM. Launching the Hub with PolkaVM, ink! will be the first competitive language that can battle test and benefit from PolkaVM's improvements, and ensure that Polkadot doesn’t just replicate Ethereum, but instead pioneers the next generation of smart contracts.

ink! is positioned to take PolkaVM to market in 2025.
At present there is only one language that can bring PolkaVM to market in 2025 on Polkadot Hub, that language is ink!. This will enable the Hub access to a developer pool that exceeds 5.1 million+ Rust devs as of 2025, across every industry - including being backed by Google. This constitutes a talent pool that is ~191 times larger than all Web3 developers combined⁴. Additionally, in the 2024 State of Rust Survey, 45% of respondents reported that their organizations now make non-trivial use of Rust (up 7% from 2023) making it an excellent choice for enterprise adoption.

⁴ Electric Capital: 2024 Developer Report.

With this, ink! delivers secure enterprise-grade contracts for the Hub.
From day one, ink! guarantees that developers can deploy secure, scalable contracts on Polkadot’s native stack, without compromise. The proposition put forth in this proposal enables a reliable time-to-market for PolkaVM smart contract readiness on the Hub in 2025, reduces technical risk, and positions the Hub as a first mover with RISC-V smart contracts.

Full Document

The full proposal can be found here: https://docs.google.com/document/d/1Brl7EJEjQ02sV8yy9PhWAuI-2_YkGrSaAs8t-obgEGE/edit?tab=t.0.