# What happens next

Everything in this directory is **unbuilt**. When a piece of it is finished it
leaves — deleted from here, rewritten as a description in
[../architecture/](../architecture/). See [the rule](../README.md#the-rule-that-keeps-this-from-rotting).

> ## Read [1.0.md](1.0.md) first.
>
> It draws a finish line and puts most of the work below on the far side of it.
> **Anything not named there is not being worked on**, and the documents in this
> directory describe more than 1.0 contains.
>
> It also holds **[the register of unfinished work](1.0.md#the-freeze-and-the-register-of-unfinished-work)**,
> which is the one place anything half-built is listed. No new capability starts
> until that register is empty, and a row leaves it only by being finished or by
> being deleted from the tree.

---

## The three current decisions

Taken together, because they turn out to need the same foundation.

| | |
|---|---|
| **[wayland.md](wayland.md)** | The GUI stack becomes Wayland. SchWM and SchDE are **deleted** — actually gone from the tree, not marked; Schcom survives and changes its wire format. |
| **[hybrid.md](hybrid.md)** | The kernel becomes hybrid — drivers move out into userspace processes, starting with the GPU. **Partly built**: all four mechanisms exist and the GPU driver already runs outside the kernel. |
| ~~init.md~~ | **Built.** PID 1 is now a role the kernel refills; the description moved to [../architecture/init.md](../architecture/init.md). |

And the one they all wait on:

| | |
|---|---|
| **[foundations.md](foundations.md)** | Descriptor passing, shared memory, sockets in the filesystem. The critical path. **Item 1 is built** — `sendmsg`/`recvmsg` with `SCM_RIGHTS`. |

And the one that says which parts of the above are actually being worked on:

| | |
|---|---|
| **[1.0.md](1.0.md)** | The finish line. Four gates, and everything else explicitly deferred. |

And one that is a tool rather than a capability:

| | |
|---|---|
| **[debugger.md](debugger.md)** | A debugger for this kernel — one that observes rather than halts, and answers in this kernel's own vocabulary. **Built**, except the network transport: symbols, a log that outlives the kernel, `/dev/dbg`, the `whose` ownership query and hardware watchpoints are all described in [../architecture/debugging.md](../architecture/debugging.md). |

Two longer-horizon documents sit behind these: [schapi.md](schapi.md), the API
layering and the compatibility promise, and [roadmap.md](roadmap.md), which holds
everything still open that is not one of the three above.

---

## The order

Set by [1.0.md](1.0.md), which is the authority. In short:

### 0. Fix what is already wrong — **first**

Not a document of its own; it is Gate 0 of [1.0.md](1.0.md), assembled from the
*What it does not do* sections in [../architecture/](../architecture/).

**Before any new capability**, and the reason is the one that put
`netdev_selftest()` before the TCP/IP stack: a compositor built on a kernel with
an unexplained hang and a socket layer that reports success for things it did not
do will fail in ways indistinguishable from its own bugs.

### 1. `foundations.md` — the critical path

Both the Wayland work and the hybrid work stop here. Descriptor passing and
shared memory are the substrate for handing a buffer to a compositor *and* for
handing a device to a driver process. **Doing it once for both is the entire
reason these are one plan rather than three.**

### 2. `init.md` — before the desktop, not after — **done**

A compositor being brought up for the first time crashes constantly, and
something that restarts it and says why is worth far more during that work than
at the end of it. Built; see [../architecture/init.md](../architecture/init.md).

### 3. `hybrid.md` — **moved up, and the reason is worth recording**

This document used to put the hybrid work *after 1.0*, deliberately last, on this
argument:

> designing a userspace driver interface with no driver consuming it produces an
> interface that is wrong in ways nobody can see

The argument was sound and the conclusion drawn from it was wrong. What forced
the change was the driver situation: SchOS cannot write a driver for every device
that exists, no project can, and the only route to the hardware support an
established OS has is a compatibility layer with the foreign drivers kept
*outside* the kernel. That layer is this plan's mechanisms. It is not optional and
it is not late work.

The original argument still holds, and it is answered rather than ignored:
**SchOS's own drivers are the consumers.** `vgpud` is a real driver, with real
requirements, and building the interface against it is what keeps it a general
mechanism rather than a hole shaped like something foreign. The compositor is
still a demanding consumer — it is no longer the *only* one available.

Four mechanisms, all built. One eviction done, one to go, then the foreign
driver host.

### 4. `wayland.md` — with the GPU driver either side of the seam

W1–W3 and a terminal. W4 and W5 are post-1.0. Item 1 of `foundations.md` —
descriptor passing — was the thing it could not start without, and it now
exists.

---

## In one sentence

> Fix what is broken, build the descriptor-passing and shared-memory substrate,
> make init survivable, move the drivers out through an interface SchOS's own
> drivers have to live with first — and put a terminal on the screen.

---

## What this plan does not address

Stated here so it is not mistaken for covered:

- **No IOMMU**, so the hybrid work isolates against bugs and not against a
  hostile driver.
- **No page cache**, so `foundations.md` delivers a `memfd` and not a general
  answer to shared file mappings. The general answer is still owed.
- **No garbage collector for descriptors in flight**, so an `AF_UNIX` socket
  passed over itself and never received leaks. Bounded at thirty-two sockets, and
  nothing on this plan does it.
- **No dynamic linking**, so no Mesa, no accelerated clients, and no third party
  shipping a `.so` for anything.
- **A new compatibility surface** between PID 1 and PID 2, created by a plan
  whose own [schapi.md](schapi.md) §3 spends a section warning about those.
- **The three open networking items** — `getsockname`, routing, and
  interrupt-driven receive — are untouched by any of this and still open. They
  are in [roadmap.md](roadmap.md).