The Lightning Network remains the most secure option.

From a purely technical perspective, many so‑called Layer 2 designs aim to perform more actions off‑chain from a single on‑chain UTXO operation, thereby reducing the burden on the base layer. This is likely one reason they are grouped under the “Layer 2” label. However, my view comes from another angle.

When it comes to Bitcoin usage, most alternatives to Lightning require introducing a pre‑defined third‑party trust model. These third parties are ultimately legal entities, which means that the assets flowing within such systems are only nominally Bitcoin. Service providers in these designs often have the ability to censor or freeze transactions under certain circumstances. Even if users retain some form of unilateral exit, Bitcoin itself is inherently supra‑sovereign, whereas the security of these systems falls below that threshold. In contrast, Lightning transactions represent actual Bitcoin, and the risk of attack is highly localized. By comparison, centralized service providers present larger attack surfaces.

From this perspective, I see non‑Lightning solutions more as on‑chain extensions that trade some security for additional functionality, whereas Lightning is the only true Layer 2. For most users, the majority of their Bitcoin will likely remain either on‑chain or in Lightning channels, rather than locked in these alternative systems, which act more like specialized functionality bridges.

In terms of design, compatibility with Lightning atomic swaps exists mainly for interoperability; in practical payment use cases, these solutions tend to operate around Lightning rather than replace it.