June 1, 2026
RNA vs Haskell: fight night
Stealing from Biologists to Compile Haskell Faster
A nerdy speed fix turned into a comment-section cage match over math, nature, and compiler pain
TLDR: A developer found a way to speed up a hidden Haskell compiler feature by borrowing ideas from biology, turning an obscure coding problem into a surprisingly big breakthrough. In the comments, readers split between awe at the elegance, “isn’t this just a known graph trick?”, and the inevitable “actually, there’s an even faster way.”
A seemingly tiny compiler tweak has turned into catnip for the extremely online programming crowd. The original story is already wild enough: a developer went digging into why a speed-up option in GHC, the Haskell compiler, is turned off by default, only to discover the fix wasn’t an easy afternoon patch at all. Instead, it led to a brain-bending problem about how to rearrange independent tasks so programs can do more work at once—and, somehow, to the same kind of math biologists use to predict how RNA folds. Yes, the plot twist here is basically: to make code faster, steal a trick from biology.
But the real fireworks were in the reactions. One commenter was practically swooning over the elegance of it all, calling the surviving hard case something that “deeply mirrors nature’s own computational machinery,” which is a very dramatic way of saying, “wow, this got weirdly beautiful.” Another camp immediately went full armchair detective: isn’t this just that graph trick everyone learns for dependency problems? Cue the classic internet ritual of smart people politely implying other smart people may be overcomplicating everything. Then came the ultimate power move: someone jumped in to say the proposed method still wasn’t fast enough and that an even better approach exists. Naturally.
So the mood was a delicious mix of awe, skepticism, and flexing. Some readers were enchanted by the biology-meets-code crossover; others treated the whole thing like an open invitation to one-up the algorithm. In other words, a perfect tech-comment drama: half science miracle, half competitive backseat driving.
Key Points
- •The article investigates why GHC’s `-foptimal-applicative-do` optimization is disabled by default despite being correct.
- •ApplicativeDo lets the compiler convert independent statements in Haskell `do` blocks into Applicative form using `<*>`, while preserving `>>=` where dependencies exist.
- •In systems like Haxl, grouping independent computations under `<*>` can batch remote operations into fewer rounds, reducing latency.
- •GHC’s default ApplicativeDo scheduling algorithm is greedy and can produce suboptimal execution plans.
- •The article states that GHC’s optimal scheduling algorithm finds better plans but has `O(n^3)` time complexity, making it expensive.