Review Code

Review changed code against all Cratis project standards and produce a structured report.

C# Architecture

• Each slice is its own folder <Module>/<Feature>/<Slice>/<Slice>.cs with all backend artifacts — no top-level Features/ wrapper
• Commands: record type with Handle() directly on them — no separate handler classes
• Business rejection returns a ValidationResult / Result<TEvent, ValidationResult> (or validator) — never thrown from Provide()/Handle() (a throw is HTTP 500, not a validation error)
• Fetched/computed handler data is in Provide(), not inline in Handle()
• Events: record type, no mutable/nullable properties, past tense, never carry the event-source id
• Identity concepts derive from EventSourceId<T> (not ConceptAs<Guid>)
• Projections: AutoMap is on by default — .AutoMap() only after .NoAutoMap(); projections consume events, never read models
• Model-bound query custom paths use [Path("...")], not [Route]
• No service locator (IServiceProvider not injected); discover implementations with IInstancesOf<T>, not IEnumerable<T>
• Namespace matches folder under the app source root (<RootNamespace>.<Module>.<Feature>.<Slice>)

C# Code Style

• File-scoped namespaces; using directives alphabetically sorted
• No unused using directives
• is null / is not null — never == null / != null
• var preferred over explicit types
• No postfixes: Async, Impl, Service on class names
• No regions
• All public types, methods, and properties have multiline XML doc comments
• <summary> tags always multiline — never /// <summary>Text</summary> on one line
• Methods with parameters include <param name="..."> for each
• Non-void methods include <returns>
• Custom exception types only — never InvalidOperationException, ArgumentException, etc.
• Exception XML docs start with "The exception that is thrown when …"
• Copyright header on every file
• Strongly-typed Concepts for all domain IDs/values (no raw Guid/string in domain models)

TypeScript Code Style

• const over let over var
• Full descriptive names — never e, idx, prev, dir, pos
• No any type — unknown with type guards
• No (x as any) — use value as unknown as TargetType
• No unused imports
• Copyright header on every file

Component Rules

• CommandDialog from @cratis/components/CommandDialog for command dialogs
• Dialog from @cratis/components/Dialogs for data-only dialogs
• Never imports Dialog from primereact/dialog directly
• No hard-coded hex/rgb colors — PrimeReact CSS variables only
• README.md present for complex component folders with multiple sub-components

Performance

Performance is part of code review, not a separate pass. Flag the common degradations:

• Projections don't join on a read model; reactors don't re-query the event log inside a handler — use event data directly
• New projections can replay all historical events without crashing; events carry no large blobs
• MongoDB queries filter on indexed fields; lists that can grow return IQueryable<T> for server-side paging (never load all rows or hydrate the full collection for a count)
• No N+1 query pattern; response payloads include only fields the client uses
• React: large/growing lists page rather than render all rows; no inline object/array literals as props that change identity every render; useEffect deps are correct
• .NET: filter before materializing (no .ToList() before .Where()); don't enumerate an IEnumerable<T> multiple times

Classify findings: 🔴 measurable degradation at moderate load (fix before merge) · 🟡 degrades under load/scale · 🟢 minor.

Output format

Start with: Review result: ✅ Approved / ⚠️ Approved with comments / ❌ Changes requested

Then list issues:

### <file path>

**[BLOCKING]** Line N: `problematic code`
Because: explanation
Fix:
```corrected code```

End with a concise summary of what passed and what must change.

For the full expanded checklists across all categories, see references/CHECKLISTS.md.