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+# Tint Architecture
+
+```
+                   +--------+                   +------+
+                   | SPIR-V |                   | WGSL |
+                   +----|---+                   +---|--+
+                        |                           |
+                        |                           |
+              +---------|---------------------------|--------+
+              |         |          Reader           |        |
+              |         |                           |        |
+              | +-------|------+             +------|------+ |
+              | | SPIRV-Reader |             | WGSL-Reader | |
+              | +--------------+             +-------------+ |
+              +-----------------------|----------------------+
+                                      |
+                                      |
+                                   +--|--+      +---------+
+                                   | AST |------| IsValid |
+                                   +--|--+      +---------+
+                                      |
+                                      |
+                             +--------|--------+
+                             | Type Determiner |
+                             +--------|--------+
+                                      |
+                                      |
+                                +-----|-----+
+                                | Validator |
+                                +-----|-----+
+                                      |
+                                      |
+                               +------|-----+
+                               | Transforms |
+                               +------|-----+
+                                      |
+                                      |
++-------------------------------------|------------------------------------+
+|                                  Writer                                  |
+|                                                                          |
+| +--------------+    +-------------+    +-------------+    +------------+ |
+| | SPIRV-Writer |    | WGSL-Writer |    | HLSL-Writer |    | MSL-Writer | |
+| +-------|------+    +------|------+    +------|------+    +------|-----+ |
++---------|------------------|------------------|------------------|-------+
+          |                  |                  |                  |
+          |                  |                  |                  |
+          |                  |                  |                  |
+     +----|---+          +---|--+           +---|--+            +--|--+
+     | SPIR-V |          | WGSL |           | HLSL |            | MSL |
+     +--------+          +------+           +------+            +-----+
+```
+
+## WGSL Reader
+
+The WGSL reader is a recursive descent parser. It closely follows the WGSL
+grammar in the naming of the parse methods.
+
+
+## AST
+
+After generation the AST will run an `IsValid` method which verifies that the
+produced AST is structurally correct. This means that things like `if`
+statements have a condition and body attached.
+
+
+## Type Determiner
+
+The type determination stage assigns a result type to each node in the AST. It
+will do the minimal amount of validation required in order to always be
+accessing valid nodes, but that doesn't mean the overall AST is valid. (e.g. a
+4 component vector type constructor with 5 components will pass type
+determination but is invalid.)
+
+
+## Validation
+
+After the validation step the AST should be a known valid WGSL program.
+
+
+## Transforms
+
+There maybe various transforms we want to run over the AST. This is for things
+like Vertex Pulling or Robust Buffer Access. These transforms will modify the
+AST and must produce valid AST after their execution.
+
+Currently the transforms are run individually but we should consider adding
+a transform manager to maintain and execute the list of transforms.
+
+
+## Writers
+
+The writers should be thread safe, we maybe generating the HLSL and MLS output
+at the same time on different threads. (The writer portion is the only one
+that needs to be thread safe.)