Bend 2's Formal Verification Demo Misses Decades of Research

Bend 2 and the Vibe-Coding Trap

Bend 2 promises AI-written proofs, but its demo requires 58 lines of laws and 442 lines of proof for a simple game. The author recreates the same demo in SPARK, an established formal verification language, using only a fraction of the code. The real issue: vibe-coding lets developers build entire languages without discovering that the field of formal verification already solved these problems.

The developer has built an entire language around a field seemingly without realising that said field exists.

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2026-09-18