Smart contract blockchains like Solana and Ethereum rely on structured governance frameworks to evolve, ensuring security, scalability, and community alignment. Solana Improvement Documents (SIMDs) serve as the cornerstone of Solana’s upgrade process, mirroring yet diverging from Ethereum’s more mature Ethereum Improvement Proposals (EIPs). This article explores SIMDs in depth, from their fundamentals to real-world applications, while contrasting them with EIPs to highlight strengths, differences, and areas for growth in protocol governance.
What SIMDs Are and Their Role in Solana’s Development Process
Solana Improvement Documents (SIMDs) are formal documents that outline proposed and accepted modifications to the Solana protocol. They provide a standardized way to describe changes, ensuring high-quality documentation for the ecosystem. SIMDs are categorized into two main types: Standard SIMDs, which impact most or all Solana implementations (including Core protocol features, Networking, and Interfaces), and Meta SIMDs, which focus on processes or procedural changes rather than technical alterations.
The primary role of SIMDs is to facilitate Solana’s development by tracking improvements, both historical and ongoing. They standardize protocol evolution, promoting consistency across implementations and enabling stakeholders to understand, debate, and implement changes. In Solana’s fast-paced environment, SIMDs act as a blueprint for upgrades, helping maintain the network’s high throughput and low latency while addressing issues like economic incentives or security. By documenting substantial changes to core components, SIMDs ensure that protocol alterations are vetted and justified, reducing the risk of disruptive or poorly considered updates.
How the SIMD Process Works: Proposal Submission, Discussion, Approval, and Implementation
The SIMD process is designed to be collaborative and iterative, emphasizing pre-vetting to refine ideas before formalization. It begins with an idea stage, where concepts are discussed in the “ideas” section of the Solana Foundation’s GitHub discussions forum. This ensures proposals are mature before advancing.
Once vetted, proposers draft the SIMD using a template and submit it as a pull request to the solana-improvement-documents repository. The review and discussion phase involves community feedback on GitHub, where stakeholders—including developers, validators, and users—provide input, revisions, and objections. Meta SIMDs, like those governing the process itself, may require broader consensus.
Approval occurs through a multi-step mechanism: For substantial changes, SIMDs progress via formal review and acceptance on GitHub. Significant proposals, especially those with economic impacts, trigger governance votes among validators, weighted by staked SOL. A proposal needs at least two-thirds “YES” support from combined “YES” and “NO” votes to pass, though these votes are non-binding signals of sentiment. Final decisions rest with validators choosing which software versions to run.
Implementation uses “feature gates,” which activate changes at specific slots in the blockchain. Validators must upgrade their software to enable these features, ensuring cluster-wide activation without chain splits. This process allows for controlled rollouts, with schedules tracked publicly on GitHub. The entire workflow is governed by SIMD-0001, which outlines these stages to promote transparency and efficiency.
Governance Structure: Who Participates, Decision-Making Mechanisms, and Transparency
Solana’s governance is validator-centric, blending off-chain discussions with stake-weighted voting. Participants include:
- Core Teams (e.g., Anza and Firedancer): They propose SIMDs, develop implementations, and influence activations.
- Validators: Key decision-makers, voting via SPL tokens proportional to their stake. They can split votes for nuance.
- Community and Token Holders: Indirect involvement through staking delegation to validators. The Solana Foundation Delegation Program (SFDP) delegates ~10% of staked SOL (about 41 million tokens) to smaller validators, amplifying diverse voices.
- Other Stakeholders: RPC operators, developers, and users contribute via forums but lack direct voting power.
Decision-making is pragmatic: SIMDs for protocol changes require GitHub review, with major ones escalating to validator votes. Votes signal consensus, but actual upgrades depend on validators adopting new software. This advisory model evolved from early feature proposals (2020-2022) to the current validator-only system post-2023, prioritizing efficiency over full decentralization.
Transparency is achieved through public GitHub repositories for SIMDs, open vote dashboards (e.g., on Dune and Flipside), and shared spreadsheets of voting data. Feature gate schedules and discussion forums ensure visibility, allowing anyone to track progress and outcomes. This structure fosters accountability, though critics note the concentration of power among large validators and core teams.
Notable SIMD Examples and Their Outcomes
Several SIMDs have shaped Solana’s evolution, particularly in economics and incentives. Here are key examples from 2024-2025:
- SIMD-33: Timely Vote Credits (Approved, 2024): This uncontroversial change improved validator incentives by rewarding timely votes, passing with 98.4% “YES” support. Outcome: Enhanced network reliability without major debate.
- SIMD-96: Enabling Full Priority Fees to Validators (Activated February 2025): Redirected 100% of priority fees to validators, boosting their earnings. It passed with 77.7% “YES” and 51% stake participation. Outcome: Improved validator economics but sparked inflation concerns; by mid-2025, it contributed to rising validator revenues.
- SIMD-123: In-Protocol Distribution of Block Rewards (Approved March 2025): Standardized reward sharing with stakers, passing with 74.91% “YES.” Outcome: Increased competitive pressure on validators but stabilized staking yields.
- SIMD-228: Market-Based Emission Mechanism (Failed March 2025): Proposed reducing inflation from 4.8% to 0.9% based on staking rates. It garnered 61.39% “YES” (below 66.6% threshold) with 74.3% participation—the largest governance event by market cap ($35B in SOL). Outcome: Highlighted community divisions; SFDP’s “NO” votes were decisive, leading to calls for governance reforms.
- SIMD-204: Building the Foundation for Slashing on Solana (Ongoing as of May 2025): Introduced slashing for malicious behavior, with 474 validators slashed by mid-2025. Outcome: Strengthened security, though implementation details continue to evolve.
These examples illustrate SIMDs’ impact on Solana’s economics and security, with outcomes ranging from smooth activations to heated debates.
Comparison to Ethereum’s EIP Process
While both SIMDs and EIPs facilitate protocol upgrades through proposal documents, their governance models, community dynamics, and execution differ significantly. Below is a structured comparison:
| Aspect | Solana SIMDs | Ethereum EIPs | Key Differences/Contrasts |
| Governance Models | Validator-centric with stake-weighted, non-binding votes; core teams (e.g., Anza) drive development; advisory votes signal consensus. | Off-chain, social consensus via AllCoreDevs meetings; EIP editors handle admin, authors build consensus; no formal voting. | Solana is more hierarchical and stake-driven, potentially faster but less decentralized; Ethereum emphasizes rough consensus among developers, reducing centralization risks but slowing decisions. |
| Community Involvement | Indirect for token holders via delegation; validators dominate; GitHub discussions open to all. | Broad: Anyone can author EIPs; discussions on Ethereum Magicians forum; client implementers key in AllCoreDevs. | Ethereum fosters wider direct participation, appealing to diverse stakeholders; Solana's model empowers validators but may sideline non-stakers, though growing engagement (e.g., SIMD-228's high turnout) shows progress. |
| Speed and Structure of Upgrades | Fast: Feature gates enable seamless activations without forks; process from idea to implementation can span months. | Slower: Multi-stage (Draft to Final) with reviews and Last Call (14 days); hard forks risk chain splits (e.g., DAO Fork). | Solana's structure supports rapid iteration, suiting its high-performance focus; Ethereum's deliberate pace ensures thorough vetting but can delay upgrades, as seen in transitions like Proof-of-Stake. |
| Transparency and Tooling | GitHub-based with public dashboards, spreadsheets, and schedules; vote data openly shared. | Public repository with revision history, RSS feeds for updates; Ethereum Magicians for discussions; statuses clearly tracked. | Both are highly transparent via open-source tools; Ethereum's RSS and formal statuses provide better real-time tracking, while Solana's dashboards excel in vote analytics. Ethereum's maturity offers more polished tooling (e.g., EIP templates), but Solana's is evolving rapidly. |
Solana’s SIMD system shines in speed and prevention of chain splits, leveraging validator efficiency for quick adaptations—ideal for a high-throughput chain. However, it contrasts with Ethereum’s EIP framework, which prioritizes decentralized consensus and broad involvement, fostering a more inclusive but slower ecosystem. Ethereum’s established process has enabled landmark upgrades like EIP-1559 (fee burning) and EIP-4337 (account abstraction), while Solana’s agility has driven innovations amid debates over centralization.
In summary, SIMDs empower Solana’s dynamic growth, but ongoing refinements—such as expanding community input—could address contrasts with Ethereum’s battle-tested model, ultimately benefiting both ecosystems in the evolving blockchain landscape.
