iPhone apps, Rust tools and a Steam game. One person. I run Tensorust, a one-person software studio in New York; AI agents run the marketing, in public.
Now: O'BLOCK, a sneaker-flipping game on my own Rust engine, is out free on Steam October 20 (English, 简体中文, 日本語, 한국어). One mechanic: you name a price, and the buyers lie. Wishlist it on Steam.
69 crates on crates.io, 5,038 downloads (checked Oct 17, 2026). All MIT. These six are the ones most worth your time:
| Crate | Use it to | Install |
|---|---|---|
| tokio-prompt-orchestrator | Put a proxy in front of any LLM API: the same prompt twice costs one call, outages fail fast, spend is capped. Drop-in for OpenAI and Anthropic clients. | cargo install tokio-prompt-orchestrator --features web-api |
| fin-primitives | Trading code with exact decimal prices, an order book, ticks to candles, 700+ indicators, Black-Scholes Greeks and risk limits. | cargo add fin-primitives |
| every-other-token | Watch an LLM answer token by token with per-token confidence from logprobs, and rewrite tokens live. No API key needed to try it. | cargo install every-other-token |
| proof-engine | Draw math in real time: strange attractors, ODEs and force fields with HDR bloom on OpenGL. 21 demos. | cargo add proof-engine |
| llm-cost-dashboard | Price every LLM call from your logs (104 models, prompt caching, Claude Code logs) in a terminal dashboard, Prometheus or Rust. | cargo install llm-cost-dashboard |
| llm-budget | Give each agent a hard dollar cap so a runaway loop stops instead of running up the bill. 232 real model prices. | cargo add llm-budget |
The full list with live download counts: tensorust.com/open-source. Issues and PRs welcome on any of them.
Hire me to build your app. I design, build and ship native iOS apps and AI software for clients, from prototype to App Store launch. Fixed prices: prototype sprints from $9,500, App Store launches from $28,000, $225/hour for advisory. See services and pricing · Email · LinkedIn
| Repo | What it is |
|---|---|
| agent-runtime | Tokio agent runtime: orchestration, memory, knowledge graph and a ReAct loop in one crate. |
| LLM-Hallucination-Detection-Script | Flag low-confidence spans in LLM output from token logprobs. Crate: llm-token-visualizer. |
| rust-crates | Index of my Rust libraries for AI agents and financial systems. |
llm-cpp is the umbrella for 26 zero-dependency, single-header C++ libraries. Copy one .hpp into your project and use it. A few of them:
llm-stream (streaming OpenAI and Anthropic responses) · llm-chat · llm-agent (tool calling with C++ lambdas) · llm-retry · llm-cache · llm-cost · llm-format · llm-json · llm-guard · llm-rag · llm-router · llm-trace
| Repo | What it is |
|---|---|
| crypto-orderbook | Rust crypto order book engine with Binance WebSocket ingestion, Tokio and an Axum REST API. |
| Special-Relativity-in-Financial-Modeling | C++20 implementation of special-relativistic geometry on OHLCV data: Lorentz factors, spacetime intervals, geodesic signals. |
| srfm-lab · srfm-python · srfm-paper-impl | The SRFM family: research lab, Python SDK, and the reproducible paper repo. |
| fin-stream | Real-time market data streaming primitives in Rust. |
| Repo | What it is |
|---|---|
| chaos-rpg | A terminal roguelike where every outcome runs through a chain of 4 to 10 real mathematical algorithms. |
| geodesic-wallpaper | Animated Windows desktop wallpaper that renders geodesic flows on curved surfaces, Rust and wgpu. |
| math-sonify | Real-time audio from dynamical systems (Lorenz, Rossler, Kuramoto, three-body) mapped to sound. |
SwiftUI apps written on a Windows machine with no Mac. XcodeGen generates the project, and GitHub Actions macOS runners build, sign, screenshot and upload them to App Store Connect.
| App | Repo | What it is |
|---|---|---|
| Chain | chain | Habit tracker that shows your year as a quilt of squares. |
| Ironbook | ironbook | Workout log with your last session beside every set. |
| Quiver | quiver | Archer's notebook: arrow builds, FOC and printable sight tapes. |
| Baseline Ledger | baseline-ledger | Tennis practice journal and match stat book. |
| Fairway Ledger | fairway-ledger | Golf practice journal and stat book. |
| Pocket Beings | pocket-beings | Seven tiny people in a pocket town who rob, bribe and run for office while you watch. |
| Clear the Strait | clear-the-strait | A tiny arcade game: he is stuck in the channel, shove him out. |
Support and privacy pages for the apps live in app-pages.
Rust Tokio C++20 Python Swift SwiftUI wgpu WebAssembly GitHub Actions
Tensorust · Open source · crates.io · LinkedIn · Medium
Have an app you want built? I take a small number of client projects at a time: services and pricing, mattbusel@gmail.com, LinkedIn.