Skip to content
View saiKasi0's full-sized avatar
πŸ’­
πŸ›Έ
πŸ’­
πŸ›Έ

Highlights

  • Pro

Block or report saiKasi0

Block user

Prevent this user from interacting with your repositories and sending you notifications. Learn more about blocking users.

You must be logged in to block users.

Content in all repositories owned by your account will be closed.
Maximum 250 characters. Please don’t include any personal information such as legal names or email addresses. Markdown is supported. This note will only be visible to you.
Report abuse

Contact GitHub support about this user’s behavior. Learn more about reporting abuse.

Report abuse
saiKasi0/README.md

πŸ‘‹ Hi, I'm Prabhav Kasibhatla

πŸŽ“ BS Computer Science & Computational Physics @ UT Austin

I build systems at the intersection of low-level performance, machine learning, and computational physics.

πŸš€ Featured Projects

  • βš›οΈ qmc-pricer Quantum Amplitude Estimation for derivative pricing, built from scratch β€” including the simulator β€” and benchmarked against classical Monte Carlo and quasi-Monte Carlo.

    • The quadratic speedup is real, and it is not enough. IQAE converges at N^-1.01 against Monte Carlo's N^-0.54 with non-overlapping confidence intervals β€” exactly what the literature promises. Scrambled-Sobol quasi-Monte Carlo reaches the same rate classically and beats every quantum method by two orders of magnitude in absolute error at every budget tested.
    • The simulator is mine. A from-scratch statevector engine in Rust β€” memory-bandwidth-aware kernels, gate fusion, rayon β€” hitting 94% of this machine's measured 270 GB/s sustained bandwidth at 26 qubits, slightly faster than Qiskit Aer. The denominator is benchmarked, not a spec sheet.
    • Two independent backends. A Rust engine (hand-written index arithmetic over a flat buffer) and a JAX engine (tensor contractions) sharing no code, agreeing with each other and Qiskit to 4e-16. A bug would have to be reproduced independently, in two languages, by two different algorithms, to survive.
    • What it would actually cost: ~9.2e12 T gates and 61 logical qubits to price one option to 1e-4 β€” and the polynomial state preparation that would close that gap is precisely what Herbert's critique targets.
  • πŸ”¬ Preimage Amortized prompt inversion, evaluated functionally. Train a model that reads arbitrary text and emits a prompt making a frozen target model reproduce that text's distribution β€” judged by whether the regeneration matches, not by string-matching a "true" prompt (which, for arbitrary text, doesn't exist). At its core: the inverse problem for a stochastic simulator, i.e. amortized Bayesian inference.

    • Amortization beats search: the reward-optimized inverter reaches 93% of best-of-8 search quality in a single call (0.681 vs 0.732 embedding similarity) β€” above a 0.637 zero-shot bar and a 0.359 retrieval floor.
    • Reward hacking, measured and priced out: ~24% of sampled candidate prompts attempt verbatim-copy strategies, with functional score correlating +0.56 with target overlap absent the guard. The n-gram guard acts as a Bayesian prior term.
    • Built so the numbers can't be artifacts: template-family-disjoint holdouts, pre-split MinHash dedup, provenance-split memorization controls separating reachability from recall, and metric sanity gates validated before any training.
    • Status: complete config-driven pipeline, 52 tests, validated end-to-end at dev tier (135M stand-in). Full-scale 8B runs are config changes pending GPU allocation.
  • 🧠 Lohalloc An intelligent, machine-learning-driven memory allocator that bridges ML and low-level systems architecture. A UCB1 multi-armed bandit learns per-call-site allocation topology during training, then freezes into a CHD minimal perfect hash table for O(1) routing at inference.

    • A specialist, honestly priced: wins mixed-size/lifetime workloads by up to 6Γ— on speed and 4–16Γ— on peak RSS β€” and loses uniform small-object churn by 1.5–1.8Γ—. Certified on bare-metal AWS Graviton across C/C++/Rust with Mann–Whitney U significance testing over raw per-run samples.
    • The bug worth reading about: the bandit kept under-selecting the bump arena. The cause wasn't the allocator β€” a 48-byte training header was landing on the arena's cold target cache line, paying exactly the cache-miss cost the arena existed to avoid. The reward signal was measuring the instrument, not the system.
    • Live Telemetry Dashboard: a custom real-time GUI (LOHA // ALLOC) monitoring heap maps, fragmentation, ops/sec, and latency β€” zero-overhead in production builds (feature-gated; verified via nm).
  • πŸŽ›οΈ CRATEDIG A real-time terminal sampler and sequencer in C++20, built because sample-based workflows are the one thing GarageBand handles poorly and the free alternatives are paywalled.

    • Hard real-time, enforced rather than intended: zero allocations, locks, syscalls, or exceptions in the audio callback β€” three lanes over lock-free SPSC rings with a janitor thread that owns all destruction, checked by global operator new replacement against a thread-local depth counter and a ThreadSanitizer-clean suite.
    • Bit-exact determinism: identical output across block sizes, run-to-run, and live-vs-offline, verified by committed golden hashes with a documented FMA-portability policy. Playback position is 32.32 fixed point, not float, so block-size invariance holds by construction rather than by luck.
    • Negative-control testing: every assertion is validated by deliberately breaking the behavior it claims to catch. It found a full suite that passed with bus routing deleted entirely.
    • Status: M5.7 of a documented 9-milestone roadmap. Chops, sequences, mixes. Not yet: recording, export, plugin hosting.
  • πŸ¦€ Iron Clad A high-performance Unix shell in Rust, built to find out how much of a shell's latency is the shell's own fault. Unified my interests in core systems engineering (architecting the shell itself) and cloud infrastructure (AWS for rigorous benchmarking and validation).

    • Performance, on parity-verified workloads: geometric mean 1.21Γ— over 15 cases vs bash β€” 1.84Γ— REPL dispatch (45.6% lower latency), 1.27Γ— spawn-and-reap at 250 concurrent jobs (21.2%), 1.24Γ— pipeline at 16 stages (19.4%), 1.14Γ— cold start (12.1%). Via posix_spawn-only execution (zero fork() calls, no CoW page-table cost), zero-copy fd passing (libc::dup2), and a borrowing parser over a recycled input buffer β€” 3 heap allocations for a simple command, pinned by a counting-allocator test.
    • Where it doesn't win, stated: parse complexity 3 sits at 0.99Γ—, still a hair behind bash. Two parse cases were worse β€” 0.80Γ—/0.83Γ—, from spawning /bin/echo on every echo β€” until an echo builtin moved them to 1.15Γ— and 0.99Γ—.
    • Measured properly: every benchmark pair is gated on a semantic parity check (stdout, exit status, and failure diagnostics must agree before timing), since Iron Clad implements a POSIX subset and an unsupported-syntax case would otherwise time bash doing work it skips. hyperfine -N at p50/p90/p99 on AWS Graviton bare metal via a zero-touch Terraform + Packer pipeline with automated isolcpus core isolation. Cold start n=100; other cases n=10, so p50 is the reportable statistic.

πŸ“‚ Also

  • πŸ“¦ WarrenDB β€” a distributed, erasure-coded, self-healing object store in Go, built as a controlled experiment in how storage systems should spend their repair I/O. ~1,200 seeded runs show corruption-aware scrub scheduling cuts unrecoverable data loss 54% at equal I/O budget, and a deterministic harness collapses 30 days of cluster failure into a 14-second bit-for-bit reproducible run over the real production code path.
  • πŸ“ˆ Proper Time β€” reproducing stochastic subordination (Clark 1973; Ané–Geman 2000) on 32M BTCUSDT tick trades: excess kurtosis collapses ~32 β†’ ~2 moving from calendar to event time, with two negative results reported alongside it and an original dΟ„/dt "clock-rate" chart showing information intensity spiking ~100Γ— around scheduled shocks.

🌱 What I'm Exploring

  • Core Interests: Systems, Machine Learning, Mathematics, Quant Research, and Quantum Computing.
  • Currently Learning: Compilers, GPU Software, Distributed Systems, Networking, and Market Microstructure.

⚑ Quick Facts

  • Pronouns: he/him
  • Fun Fact: I like coffee, basketball, and weightlifting

Pinned Loading

  1. qmc-pricer qmc-pricer Public

    Python

  2. Lohalloc Lohalloc Public

    Rust

  3. cratedig cratedig Public

    C++

  4. WarrenDB WarrenDB Public

    Go

  5. Preimage Preimage Public

    Python

  6. iron_clad iron_clad Public

    Rust