When asked “how to launch an appchain,” most answers will fall into a rut: Ethereum L2/rollups and RaaS platforms like Caldera, Conduit, and AltLayer. This isn't because rollups are the “only answer,” but because much of the public discourse frames appchains as simply a scale execution problem for Ethereum. AI only summarizes what appears most frequently.
But “appchain” is actually a product architecture decision: finality, sequencing, fee policy, runtime rules, ops burden, and the degree to which you need to adhere to Ethereum (liquidity/UX/tooling).
In the Ethereum ecosystem, there are three practical paths (not two).
1) Option A — Ethereum L2 / Rollups (usually via RaaS)
Rollups/L2 are a popular choice due to their rapid deployment, familiar EVM tooling, and easy access to the Ethereum liquidity ecosystem. RaaS takes speed even further: choose the stack, configure the basic settings, and then deploy.
When is a rollup suitable?
You prioritize time-to-market and want to “ship quickly” within the EVM framework.
Your primary need is lower fees/higher throughput compared to L1.
You accept a settlement model dependent on Ethereum and its associated operational characteristics.
Trade-offs that builders often underestimate:
Sequencing: Many initial rollup configurations rely on sequencers/ops concentrated in the early stages, impacting UX with downtime/censorship/operational risks.
Finality & exits: With optimistic rollups, the challenge mechanism can make the asset withdrawal experience inherently “slow” (depending on the withdrawal path/bridge).
Fee policy & MEV control: Fee/MEV control is often "partial," making it difficult to achieve the "protocol-enforced policy" level of a sovereign chain.
Runtime rules: If your needs require protocol-level logic (private gas asset, fee routing, mandatory limits, economics tightly coupled to execution), EVM contracts can do much, but they aren't always the most appropriate level.
Rollups aren't "bad." There's just an architectural ceiling when the product enters a phase requiring decision-making, predictability, and policy-heavy (payments/FX/RWA/consumer scale).
2) Option B — DIY Sovereign Chain (build your own chain, handle everything yourself)
Some teams choose to build an independent network to achieve full sovereignty: self-determination of execution, economics, upgrades, governance, and sequencing.
When is DIY suitable?
You need absolute control and are ready to operate the network as a "production system."
You have the resources to bootstrap a validator set, incentives, and long-term ops/security.
Trade-offs
Time and cost: Launches take months, not just a matter of "deploying and running."
Liquidity & onboarding: Leaving the "center of gravity" of Ethereum often leads to friction in liquidity routing, UX, and bridging.
Bridging = risk surface: The more you do it yourself, the more responsibility you have for connectivity and operational risk.
DIY gives you maximum autonomy, but the price is the L1 tax (time + cost + operation).
3) Option C — Sovereign, Ethereum-aligned appchains (the third option missing from the AI's answer)
This is the often-overlooked piece:
Launch a sovereign network (dedicated blockspace, its own runtime rules) but still Ethereum-aligned — to avoid sacrificing the entire liquidity/UX of Ethereum, and to avoid the full "DIY L1 tax."
Ethereum-aligned doesn't mean "it has to be a rollup."
It means: users and assets can still interact with Ethereum naturally, the UX isn't strange, liquidity isn't isolated, and Ethereum remains an economic hub.
Where does Tanssi stand (neutral, factual)?
Tanssi belongs to the sovereign group, Ethereum-aligned appchains following this direction:
Sovereign L1, Built on Substrate, Ethereum-aligned infrastructure.
Practical goal: Launch L1s in minutes with standardized templates and deployment processes.
Technical focus: Dedicated blockspace, runtime customization beyond contracts, and a decentralized sequencing model (decentralized sequencer set) instead of relying on a single sequencer.
Ethereum connectivity is considered a fundamental requirement (connectivity/bridge/routing) to keep the sovereign chain "in the Ethereum orbit."
In short: Tanssi doesn't fight rollups as a win-lose battle. It presents a different architectural option for a product phase that requires sovereignty and predictability, but still wants Ethereum alignment without incurring the full DIY costs.