vcce renders a planet with path tracing
C++26, Zig as the whole toolchain. One set of Slang shaders runs on Vulkan hardware ray tracing, a compute fallback, OpenGL and Metal. Jolt physics collides with the bricks directly, so nothing is ever meshed.
Open to workSanta Clarita, California, or remote
John Szaniszlo, full stack engineer
Lead engineer on an AI marketing platform until September 2026. Compilers, voxel engines and cockpit displays after hours.
tylua, a statically typed Lua
Lua syntax with an ML type system underneath: inference, variants, exhaustive matching, modules and functors. No implicit nil and no any. It compiles to plain Lua for every version since 5.1, or to a bytecode image that runs on its own interpreter, a Cranelift JIT, or ahead of time as one executable.
- 154,000 lines of Rust since September 2026, all mine.
- 2,106 conformance programs, each run on LuaJIT, Lua 5.1, 5.4 and the native runtime.
- Group borrowing: a checker that turns “don’t mutate while iterating” into a compile error. Specified, not yet built.
TYLshapes.tyl0 errors
type Shape =
| Circle(float) | Rect(float, float)
function area(s: Shape): float do
return match s
of Circle(r) then std.math.pi * r * r
of Rect(w, h) then w * h
end
end
print(area(Circle(2.0)))Exhaustive: leave out Rect and this does not compile.
tylua/mastermain
~/tylua$tylua run --target native shapes.tyl
3 of 3 stages
check
compile, Cranelift
run
Output12.566370614359172
Donenative, no Lua VM
~/tylua$
Two voxel engines, vcce and zoxels. The second one fixes what the first one taught me.
zoxels came first, in Zig
Bricks of 8³ voxels behind 512-bit masks, a stackless DDA in one compute shader, live editing with incremental uploads. Version 1.0 shipped in January 2026 and showed me exactly what the next engine needed.
Web by day, compilers by night.
By day I ship TypeScript, Postgres and Terraform for people who need it to work on Monday. By night it is Rust, C++ and Zig, for nobody in particular. Five of the smaller night projects:
Memai digs up the old photos
A Discord bot that reposts “on this day” pictures with the replies around them. Lambda and DynamoDB inside the free tier, or the same code on a Raspberry Pi.
jace, the coursework that became tylua
A Haskell-flavoured language that compiles to Lua, written for a compilers course. I kept going; it grew into tylua.
JCshapes.jc→ Lua
type Shape ::
Circle Float | Rect Float Float
def area :: Shape => Float
case
| Circle r => 3.1416 * r * r
| Rect w h => w * h
def main :: ()
(print (area (Circle 2)))case matches on the constructor; it becomes plain Lua.
jacemain
~/jace$jace run shapes.jc
3 of 3 stages
parse
typecheck
emit Lua
Output12.5664
Doneran on LuaJIT
~/jace$
A blog app, built for a databases course
Coursework at CSUN, three of us. The point was the schema: users, blogs, tags, follows and comments in MySQL, with FastAPI and React on top.
#sqlCtrl K
Matches
- Blogs tagged #sqlBlogs
- Users following #sqlUsers
- Comments with #sqlComments
↑↓ to moveEnter to open
mc-discord, a Minecraft mod that talks to Discord both ways
A Minecraft mod and a Velocity plugin for a server I run with friends: chat relayed between the game and Discord, accounts linked.
#minecraft
Relay onDiscord
server’s back up, come on
In the game
Discord › jjszaniszlo: server’s back up, come onVelocity, survivalLinked account
Back in Discord
survival › jjszaniszlo: on my way
Message #minecraft
whurl fetches my wallpapers, reproducibly
Linux first: Omarchy on the desktop, NixOS on three Pis, nix-darwin on the laptop. whurl pins wallpapers by hash; a desktop you cannot rebuild is a liability.
pfd and mfd, two open-source cockpit displays
Two instruments in modern C++, built for latency rather than features. MIT licensed, sole-authored.
pfd draws attitude, airspeed, altitude and heading from a 6-DOF flight model over UDP at 200 Hz. The render loop never touches the heap, and every run publishes its own jitter: 54 µs at 120 Hz.
Read the pfd sourcemfd’s moving map pulls Web Mercator tiles from CARTO or OpenStreetMap, caches them on disk, and falls back to procedural terrain when the network goes away. The map never goes black.
Read the mfd sourceThe systems page simulates hydraulics, generators, engines and fuel, with fault injection and a chaos mode for when you want a bad day on purpose. Crew alerts and checklists follow from it.
Read the mfd sourceAll page logic lives in a toolkit-free core with 84 GoogleTest cases. Qt and Gtk4 are thin renderers over one scene model, so both front ends draw the same frame from the same data.
Read the mfd source
Sunburnt Survivors, a beach survivor-like
Made in two weeks for the SPIN Summer Game Jam in Godot 4.4. I did the design, the pixel art and the music; three friends and I wrote the code. The crabs are not sorry.
Experience. One job, two products, and a lot of Terraform.
Full Stack Web Engineer, CAS BioSciences
Los Angeles · October 2025 to September 2026 · a three-engineer team
Empyris, an AI marketing platform
Lead engineer, about 81% of the commits. Agents draft the marketing; people approve it.
- Designed the architecture: TanStack Start and React 19, a contract-first oRPC API shared by the UI and the agents, Drizzle on Neon Postgres, Trigger.dev workflows.
- Built the agent kernel: nine agents with Zod-validated outputs, tool budgets and idempotent retries. Every proposal waits for a human verdict.
- 80 row-level security policies keep tenants apart, checked by a two-role test in CI.
- Every pull request gets its own preview environment, with Playwright end-to-end tests and automatic teardown.
CASGen, an AI website generator
Owned the AWS platform end to end, plus about 45% of the original Python backend.
- All infrastructure as Terraform, nine modules, planned on every pull request through Digger and GitHub OIDC. No static cloud keys anywhere.
- Moved Kubernetes from EKS to self-managed k3s on a NixOS image I bake, cutting the AWS bill 57%.
- FluxCD GitOps: 159 automated deploys, with database migrations gating each rollout.
- Built the document ingestion flow for a RAG knowledge base: about 2,000 documents and 2 million pages.
Skills and education
- Languages
TypeScript, Rust, C++23 and C++26, Python, Zig, C#, SQL, Lua, Bash
- Web and data
React 19, TanStack, Node, oRPC, Zod, Drizzle, FastAPI, Playwright. PostgreSQL with row-level security and pgvector, MySQL, DynamoDB
- Platform and AI
AWS, Terraform, Kubernetes (k3s), FluxCD, Docker, NixOS, GitHub Actions with OIDC. Agents with tool calling, RAG, approval loops
- Graphics and systems
Vulkan, OpenGL, Slang, compilers, Cranelift, real-time loops, Qt, Gtk4, GoogleTest, sanitizers
- B.S. Computer ScienceDecember 2025
California State University, Northridge.
- A.S. Computer Science2023
College of the Canyons, Santa Clarita.
- Math and computer science tutor2022 to 2025
College of the Canyons. Three years of explaining recursion to people who did not ask for it. Their exam scores went up anyway.
