Drop-in replacement · Zig-native validation · Zero-copy responses · Free-threading · dhi models

Status · Quick Start · Benchmarks · Architecture · Migrate · Why Python? · Observability · Security

Alpha software — read before using in production

TurboAPI works and has 275+ passing tests, but:

• No TLS — put nginx or Caddy in front for HTTPS
• No slow-loris protection — requires a reverse proxy with read timeouts
• No configurable max body size — hardcoded 16MB cap
• WebSocket support is in progress, not production-ready
• HTTP/2 is not yet implemented
• Free-threaded Python 3.14t is itself relatively new — some C extensions may not be thread-safe

See SECURITY.md for the full threat model and deployment recommendations.

Requirements: Python 3.14+ free-threaded (3.14t), Zig 0.15+

git clone https://github.com/justrach/turboAPI.git
cd turboAPI
docker compose up

This builds Python 3.14t from source, compiles the Zig backend, and runs the example app. Hit http://localhost:8000 to verify.

# Install free-threaded Python
uv python install 3.14t

# Install turboapi
pip install turboapi

# Or build from source (see below)

from turboapi import TurboAPI
from dhi import BaseModel

app = TurboAPI()

class Item(BaseModel):
    name: str
    price: float
    quantity: int = 1

@app.get("/")
def hello():
    return {"message": "Hello World"}

@app.get("/items/{item_id}")
def get_item(item_id: int):
    return {"item_id": item_id, "name": "Widget"}

@app.post("/items")
def create_item(item: Item):
    return {"item": item.model_dump(), "created": True}

if __name__ == "__main__":
    app.run()

python3.14t app.py
# 🚀 TurboNet-Zig server listening on 127.0.0.1:8000

The app also exposes an ASGI __call__ fallback — you can use uvicorn main:app to test your route definitions before building the native backend, but this is pure-Python and much slower. For production, always use app.run() with the compiled Zig backend.

All numbers verified with correct, identical JSON responses. wrk -t4 -c100 -d10s, Python 3.14t free-threaded, Apple Silicon M3 Pro.

  Throughput (req/s) — no middleware
  ─────────────────────────────────────────────────────────────

  GET /health (static)  ██████████████████████████████████████████████████  149,340  <- pre-rendered, zero Python
  GET /ping             ████████████████████████████████████████████████    150,000  <- cached after 1st call
  (simple_sync_noargs)  ██  6,847                                                   <- FastAPI

  GET /items/{id}       ████████████████████████████████████████████████   ~143,000  <- vectorcall (Zig arg assembly)
                        ███  8,666

  POST /users (dhi)     ████████████████████████████████████████  ~124,000           <- model_sync + pre-GIL validation
                        ███  8,200

  ─────────────────────────────────────────────────────────────
  With CORSMiddleware stacked (all routes, all methods):
  ─────────────────────────────────────────────────────────────

  GET /ping + CORS      ████████████████████████████████████████████████  ~139,000   <- Zig-native CORS, ~0% overhead
  GET /json + CORS      ███████████████████████████████████████████████   ~138,000
  POST /items + CORS    ████████████████████████████████████████  ~124,000

  ─────────────────────────────────────────────────────────────
  Avg latency (no middleware): 0.15ms    FastAPI: 14.6ms (~22x)
  Avg latency (with CORS):     0.16ms    FastAPI: 14.6ms (~21x)

• Static routes: app.static_route("GET", "/health", '{"status":"ok"}') -- response pre-rendered at startup, single writeAll
• Response caching: noargs handlers cached after first Python call -- subsequent requests skip Python entirely
• Zero-arg GET: PyObject_CallNoArgs -- no tuple/kwargs allocation
• Parameterized GET: PyObject_Vectorcall with Zig-assembled positional args -- no parse_qs, no kwargs dict
• POST (dhi model): Zig validates JSON schema before acquiring the GIL -- invalid bodies return 422 without touching Python
• CORS: Zig-native -- headers pre-rendered once at startup, injected via memcpy. 0% overhead (was 24% with Python middleware). OPTIONS preflight handled in Zig.

Every HTTP request flows through the same pipeline. The key idea: Python only runs your business logic. Everything else — parsing, routing, validation, response writing — happens in Zig.

                      ┌──────────────────────────────────────────────────────┐
                      │                    Zig HTTP Core                     │
  HTTP Request ──────►│                                                      │
                      │  TCP accept ──► header parse ──► route match          │
                       │       (24-thread pool)  (8KB buf)   (radix trie)     │
                      │                                                      │
                      │  Content-Length body read (dynamic alloc, 16MB cap)   │
                      └────────────────────┬─────────────────────────────────┘
                                           │
                    ┌──────────────────────┼──────────────────────┐
                    ▼                      ▼                      ▼
           ┌───────────────┐    ┌─────────────────────┐   ┌──────────────┐
           │  Native FFI   │    │    model_sync        │   │  simple_sync │
           │  (no Python)  │    │                      │   │  body_sync   │
           │               │    │  JSON parse in Zig   │   │              │
           │  C handler ───┤    │  dhi schema validate │   │  Acquire GIL │
           │  direct call  │    │  ▼ fail → 422        │   │  call handler│
           │  (no GIL)     │    │  ▼ pass → Zig builds │   │  zero-copy   │
           │               │    │    Python dict from   │   │  write       │
           └──────┬────────┘    │    parsed JSON        │   └──────┬───────┘
                  │             │  model(**data)        │          │
                  │             │  handler(model)       │          │
                  │             │  zero-copy write      │          │
                  │             └──────────┬────────────┘          │
                  │                        │                      │
                  └────────────────────────┴──────────────────────┘
                                           │
                                      ┌────▼─────┐
                                      │ Response  │
                                      │ (keep-    │
                                      │  alive)   │
                                      └──────────┘

On the response path, Zig calls PyUnicode_AsUTF8() to get a pointer to the Python string's internal buffer, then calls write() directly on the socket. No memcpy, no temporary buffers, no heap allocation. The Python string stays alive because we hold a reference to it.

At startup, each route is analyzed once and assigned the lightest dispatch path:

For model_sync routes, the JSON request body is parsed twice in Zig, zero times in Python:

1. dhi validation — dhi_validator.zig parses the JSON and validates field types, constraints (min_length, gt, etc.), nested objects, and unions. Invalid requests get a 422 without acquiring the GIL.
2. Python dict construction — jsonValueToPyObject() in server.zig recursively converts the parsed std.json.Value tree into Python objects (PyDict, PyList, PyUnicode, PyLong, PyFloat, PyBool, Py_None). The resulting dict is passed to the handler as body_dict.

The Python handler receives a pre-built dict and just does model_class(**data) — no json.loads, no parsing overhead.

# Before
from fastapi import FastAPI, Depends, HTTPException
from pydantic import BaseModel

# After
from turboapi import TurboAPI as FastAPI, Depends, HTTPException
from dhi import BaseModel

Everything else stays the same. Routes, decorators, dependency injection, middleware — all compatible.

from dhi import BaseModel, Field

class CreateUser(BaseModel):
    name: str = Field(min_length=1, max_length=100)
    email: str
    age: int = Field(gt=0, le=150)

@app.post("/users")
def create_user(user: CreateUser):
    return {"created": True, "user": user.model_dump()}

Model schemas are extracted at startup and compiled into Zig. Invalid requests get rejected with a 422 before touching Python — no GIL acquired, no handler called. Valid requests are passed to your handler with a real model instance.

@app.get("/async")
async def async_handler():
    data = await fetch_from_database()
    return {"data": data}

Async handlers are automatically detected and awaited via asyncio.run().

from turboapi import Depends, HTTPException
from turboapi.security import OAuth2PasswordBearer, HTTPBearer, APIKeyHeader

oauth2 = OAuth2PasswordBearer(tokenUrl="token")

@app.get("/protected")
def protected(token: str = Depends(oauth2)):
    if token != "secret":
        raise HTTPException(status_code=401, detail="Invalid token")
    return {"user": "authenticated"}

OAuth2, HTTP Bearer/Basic, API Key (header/query/cookie) — all supported with correct status codes (401/403).

Skip Python entirely for maximum throughput:

# Register a handler from a compiled shared library
app.add_native_route("GET", "/fast", "./libhandler.so", "handle_request")

The Zig server calls the C function directly — no GIL, no interpreter, no overhead.

# Before
from fastapi import FastAPI, Depends, HTTPException, Query, Path
from pydantic import BaseModel

# After
from turboapi import TurboAPI as FastAPI, Depends, HTTPException, Query, Path
from dhi import BaseModel

# FastAPI way (still works)
if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=8000)

# TurboAPI way (20x faster)
if __name__ == "__main__":
    app.run(host="0.0.0.0", port=8000)

# Install free-threaded Python
uv python install 3.14t

python3.14t app.py

turboAPI/
├── python/turboapi/
│   ├── main_app.py           # TurboAPI class (FastAPI-compatible, ASGI __call__)
│   ├── zig_integration.py    # route registration, handler classification
│   ├── request_handler.py    # enhanced/fast/fast_model handlers
│   ├── security.py           # OAuth2, HTTPBearer, APIKey, Depends
│   ├── version_check.py      # free-threading detection
│   └── turbonet.*.so         # compiled Zig extension
├── zig/
│   ├── src/
│   │   ├── main.zig          # Python C extension entry
│   │   ├── server.zig        # HTTP server, thread pool, dispatch, JSON→PyObject
│   │   ├── router.zig        # radix trie with path params + wildcards
│   │   ├── dhi_validator.zig # runtime JSON schema validation
│   │   └── py.zig            # Python C-API wrappers
│   ├── build.zig             # Zig build system
│   ├── build.zig.zon         # dependencies (dhi fetched automatically)
│   └── build_turbonet.py     # auto-detect Python, invoke zig build
├── tests/                    # 275+ tests
├── benchmarks/
├── Dockerfile                # Python 3.14t + Zig 0.15 + turbonet
├── docker-compose.yml
└── Makefile                  # make build, make test, make release

Requirements: Python 3.14t (free-threaded) and Zig 0.15+

# 1. Clone
git clone https://github.com/justrach/turboAPI.git
cd turboAPI

# 2. Install free-threaded Python (if you don't have it)
uv python install 3.14t

# 3. Build the Zig native backend (dhi dependency fetched automatically)
python3.14t zig/build_turbonet.py --install

# 4. Install the Python package
pip install -e ".[dev]"

# 5. Run tests
python -m pytest tests/ -p no:anchorpy \
  --deselect tests/test_fastapi_parity.py::TestWebSocket -v

Or use the Makefile:

make build       # debug build + install
make release     # ReleaseFast build + install
make test        # run Python tests
make zig-test    # run Zig unit tests

Or just Docker:

docker compose up --build

The "just use Go/Rust" criticism is fair for pure throughput. TurboAPI's value proposition is different: Python ecosystem + near-native HTTP throughput.

• ML / AI libraries — PyTorch, transformers, LangChain, LlamaIndex, etc. None of these exist in Go or Rust at the same maturity level. If your API calls an LLM or does inference, Python is the only practical choice.
• ORM ecosystem — SQLAlchemy, Tortoise, Django ORM, Alembic. Rewriting this in Go is months of work.
• Team familiarity — most backend Python teams can be productive on day one. A Rust rewrite takes 6-12 months and a different hiring profile.
• Library coverage — Stripe SDK, Twilio, boto3, Celery, Redis, every database driver. Go/Rust alternatives exist but are thinner.
• FastAPI compatibility — if you're already on FastAPI, TurboAPI is a one-line import change, not a rewrite.

                     req/s     p50 latency    Python needed?
Go net/http          250k+     0.05ms         No
TurboAPI (noargs)    144k      0.16ms         Yes (thin layer)
TurboAPI (CORS)      110k      0.22ms         Yes
FastAPI + uvicorn    6-8k      14ms           Yes
Django REST          2-4k      25ms+          Yes

TurboAPI won't out-run a native Go server on raw req/s. It closes most of the gap while keeping your Python codebase intact.

TurboAPI handlers are regular Python functions — standard observability tools work without special adapters.

from opentelemetry import trace
from opentelemetry.sdk.trace import TracerProvider
from opentelemetry.sdk.trace.export import BatchSpanProcessor
from opentelemetry.exporter.otlp.proto.grpc.trace_exporter import OTLPSpanExporter

provider = TracerProvider()
provider.add_span_processor(BatchSpanProcessor(OTLPSpanExporter()))
trace.set_tracer_provider(provider)

tracer = trace.get_tracer(__name__)

app = TurboAPI()

@app.get("/users/{user_id}")
def get_user(user_id: int):
    with tracer.start_as_current_span("get_user") as span:
        span.set_attribute("user.id", user_id)
        user = db.get(user_id)
        return user.dict()

from prometheus_client import Counter, Histogram, generate_latest, CONTENT_TYPE_LATEST
import time

REQUEST_COUNT = Counter("http_requests_total", "Total requests", ["method", "path", "status"])
REQUEST_LATENCY = Histogram("http_request_duration_seconds", "Request latency", ["path"])

class MetricsMiddleware:
    async def __call__(self, request, call_next):
        start = time.perf_counter()
        response = await call_next(request)
        duration = time.perf_counter() - start
        REQUEST_COUNT.labels(request.method, request.url.path, response.status_code).inc()
        REQUEST_LATENCY.labels(request.url.path).observe(duration)
        return response

app = TurboAPI()
app.add_middleware(MetricsMiddleware)

@app.get("/metrics")
def metrics():
    from turboapi import Response
    return Response(generate_latest(), media_type=CONTENT_TYPE_LATEST)

import structlog

log = structlog.get_logger()

@app.get("/orders/{order_id}")
def get_order(order_id: int):
    log.info("order.fetch", order_id=order_id)
    order = db.fetch(order_id)
    if not order:
        log.warning("order.not_found", order_id=order_id)
        raise HTTPException(status_code=404)
    return order.dict()

Middleware-based tracing works today on enhanced-path routes (those using Depends(), or any route when middleware is added). The Zig fast-path routes bypass the Python middleware stack for throughput — if you need per-request tracing on every route, add a middleware and accept the ~24% throughput overhead.

Open an issue before submitting a large PR so we can align on the approach.

git clone https://github.com/justrach/turboAPI.git
cd turboAPI
uv python install 3.14t
python3.14t zig/build_turbonet.py --install   # build Zig backend
pip install -e ".[dev]"                        # install in dev mode
make hooks                                     # install pre-commit hook
make test                                      # verify everything works

• dhi — Pydantic-compatible validation, Zig + Python
• Zig 0.15 — HTTP server, JSON validation, zero-copy I/O
• Python 3.14t — free-threaded runtime, true parallelism

MIT