README

AGENTS.md

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    a summary; iterate on the plan before writing any code.
 3. Only start implementing after the plan is approved.
 
+### README
+
+Keep `README.md` in sync with the project as it evolves. Update it when:
+- The directory layout changes meaningfully
+- Language, toolchain, or build system decisions are settled
+- Dependencies are added or removed
+- The project reaches a notable milestone
+
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README.md

@@ -0,0 +1,35 @@
+# Prism
+
+A node-based image compositing tool. Images flow through a directed acyclic
+graph (DAG) of processing nodes (read, blend, colour-grade, etc.) and are
+rendered via GPU shaders.
+
+## Status
+
+Early development. Scaffolding and exploratory scratchpad work.
+
+## Language & Tooling
+
+- **Language**: C11 / C++11 (dual-mode), following conventions in `src/wapp/`
+- **GPU API**: Vulkan, abstracted behind a Rendering Hardware Interface (RHI)
+- **Shading language**: Slang (`src/shaders/`)
+- **Build**: TBD
+
+## Dependencies
+
+- `src/wapp/` — local utility library (vendored, provides allocators, arrays,
+  strings, platform abstractions, etc.)
+
+## Project layout
+
+```
+src/prism/prism.h        umbrella include
+src/prism/core/          graph, node types, DAG
+src/prism/rhi/           rendering hardware interface
+src/prism/node/          node implementations
+src/prism/app/           entry point, window, main loop
+src/shaders/             Slang shader sources
+src/wapp/                vendored utility library
+documents/               research notes and plans
+references/              third-party reference implementations
+```