glitchfix

Shivanjan Chakravorty.

Writing

2026
Scan once, scatter once
cutting route reads 48x in the scheduler of Cursor's MoE megakernel, and the third sighting of the same bug
07 aug 2026 1 figure mixture-of-kittens #10, open
Machines that imagine ahead
the thesis this notebook keeps circling: acting well requires rehearsing the future, and rehearsal only matters if it costs less than reality
06 aug 2026
Where the eight seconds were hiding
packing narrow QK into FP8 and hunting memory traffic: 1.297 to 1.167 minutes, 5.15% under the record's same-node baseline
05 aug 2026 modded-nanogpt #344, open
The operating plan
an operating plan written down in public so it can be graded later
27 jul 2026
96 is enough: shrinking attention's routing vectors
Q and K decide where to look; V carries what's found. They don't need the same width.
24 jul 2026 1 figure modded-nanogpt PR #344
Move the index, not the data
a 3.53x MoE routing speedup, and the general principle hiding under it
10 jun 2026 1 figure cosmos-framework #20, merged
Three small patches, three training-system lessons
a hook, a metadata dialect, and test coverage: what Megatron-LM taught me about extension seams
16 may 2026 Megatron-LM #4596 #4664 #4686
Anisotropic voxels, or why medical volumes hate cubes
CT stacks are 6:1 anisotropic. Resampling to cubes costs 6x memory and invents data. Now in Warp 1.13.0.
06 may 2026 1 figure warp c64a6c3, in 1.13.0
Making a video model fit: distill, cache, offload
getting a 14B image-to-video pipeline through a 48 GB card, and what each trick trades away
14 apr 2026
Contact lists that remember
bonded-particle DEM needs pair state that survives the substep. I proposed it upstream; it wasn't taken. The idea still matters.
12 mar 2026 warp PR #1271, closed
Guardrails that compile
one policy source emitting both prompt-injection filters and AppArmor profiles, so the model's rules and the pod's rules cannot drift apart
18 feb 2026