The IR called them react-message and django-message, so a FastAPI channel had to declare a DjangoMessage. They are client-message and server-message now, and the direction words hold wherever a channel is declared: Params / ClientMessage / ServerMessage, with mizan-core deriving <Pascal>Params and friends so no backend names a type itself. Django's ReactChannel and FastAPI's ReactChannel are both Channel. mizan-fastapi never registered a channels extension, so build_ir() emitted no channel at all and every payload type was invisible to codegen. It registers one now. RegistryExtension is an ABC requiring all(), which is what the IR reads — an extension that cannot enumerate its registrations no longer exists. The gate that should have caught the rename could not: tests/afi registered no channel because mizan-rust had no channel registry to register one in, so a five-package rename of the wire contract passed byte-parity without a channel byte crossing it. mizan-rust grows ChannelSlotKind, a CHANNELS slice, a #[mizan::channel] macro, and KDL emission whose wire_to_pascal matches Python's split; the AFI fixture now carries a channel with every slot and one with a single slot, so all three backends prove the contract byte for byte. MizanChannel held three Option<String> beside three has_*() predicates and unwrapped them with defaults; it holds an ordered slot vector, so an absent slot is absent rather than defaulted. The channels target emitted a React hooks file that a stage1-only consumer could not compile — react emits that now. The codegen's parity tests byte-compared emitted source against baselines without ever compiling it: they compile the generated crate and run its tests, import the generated Python package and call every method, and typecheck each TypeScript target against a consumer. Also fixed at source: app_visitor printed its import diagnostic to stdout, the stream export_mizan_ir writes KDL to, so a failed import silently corrupted the IR; the apps root was hardcoded to "apps"; _default_literal crashed build_ir on any non-JSON-serializable field default; Django and mizan-core derived Pascal names two different ways, disagreeing on every dotted channel name. ir.py builds a document and renders templates/ir/document.kdl.j2 rather than appending KDL strings with hand-tracked indentation, and named types resolve to a fixed point — a model reachable only through a union branch was referenced by a ref that no type block ever defined. The rest is the write-gate's own classifiers run over the standing tree: relative imports, silent swallows, Protocol contracts that should be ABCs, emitters hand-rendering target source, catch-all arms over closed enums, and comments narrating the project rather than the code. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Mizan
Mizan is an Application Framework Interface (AFI). A single @client decorator on a
server function generates a typed frontend client; cache invalidation and caching are
handled by the protocol.
from mizan import client, ReactContext
UserContext = ReactContext('user')
# Context function — bundled into GET /api/mizan/ctx/user/
@client(context=UserContext)
def user_profile(request, user_id: int) -> UserShape:
return UserShape.query(lambda qs: qs.filter(pk=user_id))[0]
# Mutation — invalidation scoped automatically by matching param name
@client(affects=UserContext)
def update_profile(request, user_id: int, name: str) -> dict:
...
Adapters
Backends: Django (backends/mizan-django, the reference implementation), FastAPI
(backends/mizan-fastapi), Rust/Axum (backends/mizan-rust-axum), Tauri
(backends/mizan-tauri), and TypeScript (backends/mizan-ts). Frontends are generated
from the KDL IR over the @mizan/base kernel; frontends/ holds the kernel, the
per-framework adapters, and the transports.
Per-adapter transport shape:
- Tauri's transport is Tauri IPC (a single
#[tauri::command]envelope), not HTTP. Invalidation rides in the JSON response body; there is no header channel. - Rust/Axum and Tauri are the IR authority via the
#[mizan::client]macro + linkme registry; the codegen links the crate directly (build_ir()/ theexport-irbin) rather than fetching over HTTP. - "API shapes" is Django's django-readers queryset projection — ORM-coupled. Every adapter carries typed input/output through the KDL IR; the projection primitive itself is Django-only.
- FastAPI and Rust/Axum expose
GET /session/returning a null CSRF token for wire parity; CSRF is Django-only. - TypeScript is an edge/protocol-reference adapter (HMAC cache, manifest, PSR), not a codegen source — it demonstrates the cache + invalidation protocol is language-agnostic.
Caveat: Rust/Axum and Tauri accept
auth=on a function but their dispatch paths do not enforce it — do not rely onauth=for access control on those adapters.
Auth-provider integration (django-allauth) lives in its own repository,
mizan-allauth — a dedicated Django system built on mizan-django's forms and
context primitives.
Conformance
Per-adapter capability support is measured by the AFI conformance suite in
tests/afi/, not maintained as prose — the suite asserts IR-shape
parity: the same fixture through Django, FastAPI, and the Rust adapter emits
byte-identical KDL (test_codegen_parity.py).
Documentation
docs/— architecture references: AFI, SSR, cache keying, MWT, PSR vs. EdgeINVARIANTS.md— the AFI invariants every adapter satisfiesROADMAP.md·ISSUES.md
License
Mizan is licensed under the Elastic License 2.0 (SPDX: Elastic-2.0). You
may use, copy, modify, and distribute it freely, including in commercial products you
build on top of it. You may not provide Mizan to third parties as a hosted or
managed service that exposes a substantial set of its features.