# 💎 Nika Diamond

The ground-up rewrite of Nika into a clean, AI-refactorable workspace
of 42 small crates. This document is the strategy overview. For
the authoritative architectural decision, see
[ADR-001 — Diamond orphan branch](docs/adr/adr-001-diamond-orphan-branch.md).

- **Branch** — `main` (default · production). Orphan branch, no shared
  history with `brouillon` (renamed 2026-05-06 from the previous
  side-name `nika-diamond` · renamed per ADR-001 amendment).
- **Brouillon** — reference only, read-only, where legacy Nika v0.79.3
  lives. Accessed via `git show brouillon:path/to/file.rs` when guidance
  is needed. Never copy-pasted — every crate is rewritten clean.

For the project's landing page, see [`README.md`](README.md). For
the current status (0.124 is the current release line: work stays focused on
maintenance, security and the media capabilities workflows need, native video
is planned for 0.125, and no 1.0 launch is planned) and the historical
real-semver plan it followed until 0.123 (amended D-2026-06-20-N1 ·
was "forever-v0.x"), see [`ROADMAP.md`](ROADMAP.md); the CHANGELOG top names the
latest tagged release. For the earlier
**10-year architectural horizon
(2026 → 2036)** with the ADR-037 count horizon (50-90 · cap 100 ·
projected, never a gate · ruled D-2026-07-21-N1), 4-verb stress test
through 2036, 7-ADR queue (050-056) and per-crate detail, see
[`docs/architecture/BLUEPRINT_2036.md`](docs/architecture/BLUEPRINT_2036.md)
(proposal-grade · annual decennial review 2027-04+ · version lives in
its frontmatter, not here).

**Memory subsystem note** · Diamond and the memory cluster are
**orthogonal** (per `naming-memory-subsystem.md` v2.4 external rule).
Diamond = construction METHOD (modular crates · 12-gate admission ·
L0→L5). The memory and retrieval satellites = 10 L1 crates · publishable
standalone on crates.io · implementing `nika-kernel` traits, each capability
under its own owner and release acceptance; the former Connectome umbrella and
its L2 orchestrator are retired (D-2026-10-08-N1).
Moat framing: « unified Rust runtime contract ».

## Why rewrite into a Diamond

The legacy `nika-engine` reached 138,724 LOC in a single crate. Claude
Opus 1M holds ~75k LOC in context. A hypothetical AI assistant working
on the engine sees roughly 54% of it and has to guess the rest —
which produces hallucinated refactors. Over two weeks of real work,
this yielded only 156 lines of genuine change.

The Diamond solution: split the codebase into small crates, each
**≤ 25,000 production LOC** (15,000 until ADR-154), each small enough to
read with its tests and kernel traits in view. At the original 15,000-line
size, context headroom flipped from ~25% to ~93%. Hallucinated refactors stop.

The full argument is in
[`docs/architecture/ai-velocity.md`](docs/architecture/ai-velocity.md).

## What Nika is

Nika is a workflow engine for AI — a single Rust binary that reads a
YAML file and executes a DAG of verbs:

```yaml
# workflow.nika
nika: summarize-article
permits:
  net: { http: ["example.com"] }
  tools: ["nika:fetch"]
tasks:
  fetch:
    invoke:
      tool: "nika:fetch"        # fetch is a builtin tool, not a verb
      args: { url: "https://example.com/article", mode: article }
  summarize:
    with: { text: "${{ tasks.fetch.output }}" }
    infer: { prompt: "Summarize in 3 bullets: ${{ with.text }}" }
```

Four verbs: `infer`, `exec`, `invoke`, `agent`. (Fetching a URL is
*calling a tool*, not a distinct execution model — it is the
`nika:fetch` builtin, reached via `invoke`.) A typed
schema, a taint-tracking template engine, and a layered kernel of
side effects. LLM providers speak wire-direct through the kernel http
seam (`nika-providers` · rig NOT carried per D-2026-05-22-N17); MCP
servers via `rmcp`.

## Crate architecture

Crate count: ADR-037 horizon **50-90** (reached additively across the 1.x
minors), hard cap 100 ever — the count is projected
(`scripts/crate-metrics.sh`), never a gate (ruled D-2026-07-21-N1).
Strict downward-only layering (L0 → L5):

```
L5   nika                         binary, <500 LOC composition root (the `nika` bin target already lives in nika-cli · ADR-135)
L4   cli · daemon · serve · mcp-server · lsp · sdk · init · catalog-verify
L3   runtime · shield · wasm-host · sandbox-{linux,macos,windows}
L2   verb-{exec,invoke,infer,agent} · policy · builtin ·
     builtin-{github,cloud,workspace} · mcp · display ·
     media-{cas,image,pdf,document,provenance} · pck
L1.5 providers (16/16 per canon.yaml) · infer-local (candle · ADR-091)
L1   clock · fs · http · blob · exec-runner · screen · ocr · a11y ·
     input · browser · bm25 + the memory and retrieval satellites (hnsw · rrf ·
     rerank · fsrs · rdfs-reasoner · temporal · graph-algos ·
     autodesc-{minimal,full}) · git · keys-* · pck-{registry,store}
L0.5 kernel (facade) · kernel-{core,ai,runtime,plugin} · kernel-mock
L0   types · error · catalog · catalog-codegen · schema · event · pack ·
     binding · pck-manifest
```

(The enforced canon is
[`docs/architecture/crate-layer-registry.md`](docs/architecture/crate-layer-registry.md)
— this tree mirrors it; live admission counts come from
`scripts/refresh-status.sh`.)

Invariants enforced by CI:
- Every crate ≤ 25,000 production LOC (a warning above 15,000).
- Every file ≤ 2,500 LOC (a warning above 1,500).
- Every function ≤ 100 lines.
- Zero `.unwrap()` / `.expect(` in `src/` (CI-enforced).
- L0 has no async, no I/O, no heavy deps (tokio, reqwest, rayon rejected).
- Every side effect behind a kernel trait (testable with `nika-kernel-mock`).

Full layer map + allowed I/O axes:
[`docs/architecture/crate-layer-registry.md`](docs/architecture/crate-layer-registry.md).

## 12 gates per crate admission

A crate enters `Cargo.toml` `members = [...]` only when **all 12**
gates are green in the same atomic commit. Full spec:
[ADR-003](docs/adr/adr-003-12-gate-admission.md).

1. **Spec** — `docs/crate-specs/<name>.md` exists (purpose, layer, LOC budget, public API)
2. **TDD** — tests written before implementation (RED → GREEN)
3. **Impl** — compiles, tests pass, no temporary code
4. **Clippy 0** — `cargo clippy --workspace --all-targets -- -D warnings`
5. **Mutation ≥ 90%** — `cargo mutants -p <name>`
6. **Property** — `proptest` on sensitive surfaces (parsers, encoding)
7. **Benchmarks** — `benches/` on hot paths (exempt otherwise, documented)
8. **Docs** — `cargo doc --no-deps` zero warnings
9. **Canary E2E** — `tests/canary-<name>.nika` (exempt L0-L1)
10. **Legacy parity** — golden test vs `git show brouillon:...` output
11. **Review swarm** — three agents in parallel, P0/P1 fixed same session
12. **Atomic commit** — one admission, one commit

## 7 pre-launch shadow zones (the plan before 0.123)

The plan required all seven to be green before a `v1.0.0` tag (the first
public launch it described · amended D-2026-06-20-N1). After 0.123 that launch
is not planned; the list stays as the record of what the plan named:

1. `nika serve` input trust (P0 prompt injection boundary)
2. Cross-provider structured output parity (~35 tests)
3. `binding/template` hardening (legacy 7,243 LOC file + 15 unwraps — auto-resolved by Phase 1 `nika-binding` rewrite)
4. L1 taint analysis at runtime (lint-only today)
5. `for_each` per-element spotlight
6. `NikaError` Display parity — auto-resolved by `nika-error` admission
7. Provider parity matrix (~72 tests)

## Release model (real semver · amended D-2026-06-20-N1)

0.124 is the current release line: work stays focused on maintenance,
security and the media capabilities workflows need, and native video is
planned for 0.125. The 1.0 rows of the ladder below were the plan until 0.123
and are not planned.
That plan was real semver toward a **1.0** public launch (was "forever-v0.x" ·
retired D-2026-06-20-N1). Each release is diamond-grade for its declared scope —
the craft standard, not the scope list. SQLite shipped a 1.0 and kept
adding WAL, FTS, JSON1, window functions while staying diamond-grade at
every release — that is the model. The nine-key **LANGUAGE** envelope is
frozen forever and is orthogonal to the engine's binary version. See
[ADR-002](docs/adr/adr-002-forever-v0x.md).

The version ladder as the plan stood before 0.123 (no per-tag dates · quality > speed):

- **release-candidate grade reached at 0.91.0**: usable vertical slice (4 verbs, 16 providers per canon.yaml, effects, static-check, MCP/LSP, CLI), headless workspace build — the CHANGELOG top names the current release.
- **0.x previews** (`vX.Y.Z-preview.N`) — an optional pre-release of a 0.x wave: never the Latest release, never in the Homebrew formula, on npm under `next` only, never announced. `rc` stays reserved for 1.0.0.
- **1.0.0-rc.N** — design-partner hardening, 7 shadow zones green.
- **1.0.0** — **first public launch**: language + installable binary, validated.
- **1.x minors** — add the remaining crates additively under the ADR-037 count horizon (50-90 · cap 100 · projected, never a gate) (pck, native API adapters, WASM plugins, full observability, full LSP, keys subsystem).
- **next major** — reserved, un-numbered and unnamed, its content the operator's to declare (D-2026-07-10-N4). Memory, retrieval and cognition capabilities meet their own release acceptance under explicit owners, with no Connectome umbrella or era (D-2026-10-08-N1).

Full breakdown: [`ROADMAP.md`](ROADMAP.md).

## Method

This is **not an extraction**. This is **craft**.

Each crate is rewritten from scratch, guided by the legacy code on
`brouillon` via `git show brouillon:path` but never copy-pasted. Every
`.unwrap()` becomes `?` propagation. Every file >2,500 LOC gets
split into modules. Every function >100 lines gets decomposed. Every
public API gets `#[non_exhaustive]`, a `new()` constructor, a spec,
and tests before implementation.

The butterfly on the logo stood for what the rewrite aimed at: the
chrysalis opening at a 1.0 launch (amended D-2026-06-20-N1). After 0.123 that
launch is not planned; 0.124 is the current release line.

## License

AGPL-3.0-or-later — see [`LICENSE`](LICENSE). Commercial relicense
(Grafana model) available for enterprise consumers. Contact:
`contact@supernovae.studio`.

© 2024-2026 [SuperNovae Studio](https://supernovae.studio)

🦋 Nika — the butterfly on the SuperNovae flag.