The page starts where the paper starts: not with code, but with a formal spec stack. Step through the generation loop to see how SYSSPEC narrows ambiguity before code appears.
Maintenance Gravity
The paper’s provocation is economic: file system engineering is dominated by upkeep. This radial composition compresses the Ext4 commit history into one maintenance-biased field.
Attention Split
Why not prompt an LLM directly? Because functionality, modularity, and concurrency compete for model attention. Structured specs separate those constraints instead of asking one prompt to juggle all of them.
SYSSPEC uses Hoare logic for behavior, rely-guarantee contracts for module boundaries, and explicit lock-order protocols for concurrency. Hover cells to inspect where each layer carries the most load.
Constraint Triangle
The system works because the three spec families are complementary, not redundant. Each one removes a different kind of ambiguity from generation.
Validator Pressure Map
Mock module-by-module retry intensity: the more cross-cutting the semantics, the more validation pressure accumulates before convergence.
These are realistic mock comparisons shaped by the episode’s claims: manual development pushes effort into long bug tails, while SYSSPEC moves cost toward specification and regeneration.
Module Convergence
Most modules reportedly converge in a handful of retries. This mock line chart visualizes that “few-shot plus critique” behavior rather than one-shot synthesis.
Feature Tail Compression
Fast commits in Ext4 triggered a long bug tail. The generative thesis is that stronger specs flatten the aftershock curve.
Patches land on the specification graph, not the emitted C. Toggle between a localized feature addition and a more structural change to see how regeneration spreads across modules.
Regeneration Impact Grid
Each row is a feature patch; each column is a file system subsystem. Hotter cells mean more regeneration pressure.
Spec Patch Timeline
Evolution becomes a sequence of spec deltas with invariant checks between them, rather than a dense trail of code edits.
References
Compact links for the papers and episode context behind the visuals.