Async-first MongoDB ODM with a Django-style API - for Django, FastAPI, gRPC and plain Python

Aggify 1.0 is a complete rewrite: no MongoEngine, native async/await on pymongo's AsyncMongoClient, an API you already know from the Django ORM, and aggregation pipelines that fit on one line.

import aggify
from aggify import Document, StringField, DecimalField, ReferenceField, Sum, Count

aggify.connect("mongodb://localhost:27017/shop")

class Customer(Document):
    name = StringField(required=True)
    country = StringField(max_length=2)

class Order(Document):
    customer = ReferenceField(Customer)
    status = StringField(choices=["new", "paid"], default="new")
    total = DecimalField()

best = await (
    Order.objects.filter(status="paid", customer__country="DE")      # $lookup + $unwind + $match
    .values("customer__name")
    .annotate(revenue=Sum("total"), orders=Count())                  # $group
    .filter(orders__gte=3)                                           # HAVING
    .order_by("-revenue")[:10]                                       # $sort + $limit
    .alist()
)

Highlights

• Sync and async - every I/O method has an a-twin (aget, alist, asave, acount, aupdate, ...); one async client per event loop, so it is safe in FastAPI, grpc.aio, Django's async_to_sync and pytest-asyncio.
• Django-style - Model.objects, Q, F, annotate, aggregate, values, select_related, get_or_create, signals, managers, DoesNotExist, pagination-ready querysets.
• Complex queries, short - automatic joins (owner__country="DE"), values().annotate() grouping, conditional aggregates (Sum("x", filter=Q(...))), window functions, $facet, $bucket, $graphLookup, sub-pipeline $lookup, array operators, atomic expression updates. See the cookbook.
• Framework-agnostic integrations - pip install "aggify[fastapi|grpc|django|pydantic]". Pydantic schemas from documents, FastAPI lifespan/errors/pagination, gRPC status mapping, Django app/forms/shortcuts/middleware, and an ObjectIdField to link Django ORM models to Mongo documents.
• Secure by default - typed fields stop operator injection ({"$ne": ""}), regex lookups are escaped, server-side JavaScript is blocked, field names validated, strict constructors, resource limits, masked credentials.
• Efficient - save() sends only changed fields, optional optimistic locking, only()/defer()/values(), streaming iterators, bulk operations.
• Well tested - 470+ tests: unit, integration against a real replica set, differential property tests (random Q trees vs. a Python reference), FastAPI/gRPC/Django end-to-end tests, Python 3.9-3.13.

Install

pip install aggify                       # core (pymongo >= 4.13)
pip install "aggify[fastapi]"            # + pydantic / fastapi helpers
pip install "aggify[django]" "aggify[grpc]" "aggify[all]"

A tour

# models: typed fields, embedded documents, references, indexes
class Account(Document):
    username = StringField(required=True, unique=True)
    tags = ListField(StringField())
    address = EmbeddedField(Address)
    created_at = DateTimeField(auto_now_add=True)
    class Meta:
        ordering = ["username"]
        indexes = [Index("tags")]

# CRUD - only changed fields are written
acc = await Account.objects.acreate(username="ali", tags=["vip"])
acc.address = Address(city="Tehran")
await acc.asave()                               # {"$set": {"address": {...}}}

# querying
Account.objects.filter(Q(tags="vip") | Q(address__city__istartswith="te"), ~Q(banned=True))
Account.objects.filter(age__gt=F("score") * 10).only("username")[:20]

# atomic updates, including server-side expressions
Account.objects.filter(pk=acc.pk).update(inc__logins=1, push__tags="beta")
Product.objects.update(price=Round(F("price") * Value(1.1), 2))

# transactions (replica set)
async with aggify.atransaction():
    await Order.objects.acreate(...)
    await Product.objects.filter(pk=pid).aupdate(inc__stock=-1)

# the compiled query is always inspectable
Account.objects.filter(address__city="Tehran").query

Need a stage a queryset does not have? The immutable pipeline builder is one call away:

from aggify import Aggify
Aggify(Order).filter(status="paid").facet(
    by_country=Aggify(Order).group("customer__country", n=Count()),
    page=[{"$limit": 20}],
).execute()

Documentation

Full documentation lives in docs/ (build with make docs): quickstart - models - querying - pipelines - cookbook - security - testing - Django - FastAPI - gRPC - MongoEngine migration - upgrading from 0.x - فارسی.

Development

make install && make mongo && make test      # needs Docker for the throw-away MongoDB replica set

See CONTRIBUTING.md. Security reports: SECURITY.md.