Arcium’s roadmap is evolving. With the upcoming launch of Public Testnet Phase 2, we are introducing two changes to our rollout strategy:

• Mainnet Alpha: The first production-ready version of the Arcium Network, launching on Solana in Q4 2025. Nodes will be managed by Arcium alongside select industry-trusted validators. This accelerates ecosystem growth, removes testnet bottlenecks for ready teams, and generates early revenue ahead of full decentralization.

• C-SPL (Confidential SPL-Token): Launching directly on Solana Devnet during Phase 2, this will enable developers to begin building with the token standard sooner—preparing them to ship C-SPL-powered applications for mainnet launch.

The incredible demand for C-SPL has prompted key technical upgrades to both Arcium and Solana. In close collaboration with core Solana devs and teams, we are building C-SPL to become the ecosystem standard for confidentiality.

The introduction of Mainnet Alpha allows us to keep pace with our original mainnet timeline while simultaneously shipping the ecosystem-defining C-SPL standard and major performance optimizations—such as batch processing in MPC and parallelized computation. This reflects Arcium’s mission: to deliver the most performant, secure, and flexible infrastructure for encrypted compute, privacy-preserving applications, and standardized confidentiality on Solana and beyond.

Looking Back: Public Testnet Phase 1

Phase 1 marked Arcium’s transition from private to public testnet. The goal was to ship the initial Arcium programs and battle-test our infrastructure. The real value came from breaking things, fixing them, gathering feedback, and continuously optimizing.

During this phase, we:

• Introduced the first demo and ecosystem applications.
• Successfully ran internal clusters managed by the Arcium team.
• Launched a fully operational network explorer.

Along the way, we resolved performance bottlenecks—most notably in the Dark Pool app.

Phase 1 Highlights:

• Team and ecosystem shipped the first applications: Dark Pool, Umbra, Hidden Warrior, and Arcane Hands.
• Opened the $65K developer fellowship
• Announced a non-incentivized testnet with our novel RTG approach
• Improved node stability, parallel scheduling and execution, and expanded Arcis’ feature set

We’re grateful to the developers and community members who contributed to Phase 1. This was just the beginning. Phase 2 will bring the first fully featured network, expand applications, and serve as the initial playground for C-SPL.

Up Next: Public Testnet Phase 2

Phase 2 is the culmination of everything built over the past year. It will deliver the first fully featured version of the Arcium Network with:

• Third-party node operation
• Enhanced preprocessing model
• Batch processing for major performance gains
• A broader demo and application ecosystem

Phase 2 also brings two major launches: C-SPL on Solana Devnet and Mainnet Alpha.

C-SPL on Solana Devnet

Arcium’s Confidential SPL Token Standard (C-SPL) combines SPL-Token, Token-22, the Confidential Transfer Extension, and Arcium into a unified standard for token confidentiality on Solana.

With C-SPL, DeFi, payments, stablecoins, and more gain an ecosystem-wide confidentiality standard alongside SPL-Token. It will launch on Solana Devnet during Phase 2, enabling teams to begin testing and integrating immediately.

Our goal is clear: Equip Solana with the missing piece for confidential actions, unlocking new use cases and accelerating mainstream adoption.

Arcium’s Mainnet Alpha

We’re excited to announce Mainnet Alpha in Q4 2025, a strategic shift that brings Arcium live on Solana Mainnet with select third-party node operators and validators ahead of full decentralization.

This delivers production-ready infrastructure for partners, prioritizing real-world usage and traction in parallel to C-SPL development. The controlled approach provides stability while allowing us to optimize performance, improve developer experience, and expand integrations in a live environment.

It also marks the first time Arcium’s encrypted supercomputer powers applications on Solana Mainnet, a huge milestone for Arcium, its community, and toward adoption, growth, and proof of value.

Public Testnet Phase 3

In parallel with Mainnet Alpha, we will release Public Testnet Phase 3, the final proving ground before full mainnet launch.

Phase 3 will focus on pure acceleration of encrypted compute and the Arcium ecosystem. Planned milestones include:

• Testnet token staking and delegation
• Cheater detection and enhanced security
• Partnership application reveals
• Mainnet readiness campaigns to onboard developers, partners, and community at scale

Phase 3 bridges Mainnet Alpha with the last network optimizations, propelling us to full Mainnet launch and TGE. 

Full Mainnet Launch

The fully decentralized mainnet and TGE are scheduled for Q1 2026. By then, Arcium will have:

• Deployed and operated successfully on Solana Mainnet through Mainnet Alpha
• Shipped live applications with ecosystem partners
• Established C-SPL as a core confidentiality standard across Solana

Mainnet launch will deliver an industry-ready network for encrypted computation and privacy preservation across Web3, enterprise, and beyond. We intend to have multiple novel applications live, with Arcium already embedded as a foundational network through Mainnet Alpha. From there, Arcium will expand into new ecosystems, establishing encrypted compute as the default for powering next-generation applications.

A note to the community

We are beyond grateful for the ongoing support and dedication the Arcium community has shown so far. Many members have taken initiative, provided valuable feedback, and shipped some of the first encrypted applications on testnet. Now, we are approaching an exciting point for the community. 

As outlined in our community plan, “Encrypted, Not Extracted,” Arcium’s testnet is not incentivized, and we are not conducting an airdrop. Instead, we’ve designed a new system called Retroactive Token Grants (RTGs). With our updated roadmap, we’re preparing to announce the first wave of RTG-eligible users. Our goal is to ensure that 90% of eligible users know they will receive a grant well ahead of TGE through multiple waves of RTG announcements leading up to the full mainnet launch.

More information on the RTG program, eligibility, and the claim process will be available as we approach Mainnet Alpha. 

Conclusion

With Phase 1 complete and Phase 2 imminent, the foundation for a powerful, decentralized, encrypted compute network is set. Demand for C-SPL has accelerated our rollout, prompting Mainnet Alpha ahead of the full mainnet launch.

The road ahead includes performance improvements, expanded ecosystem support, and partner applications. We’re entering a pivotal stage in Arcium’s journey.

For news and updates, follow us on X and subscribe to our Substack. The future is <encrypted>.