diff --git a/packages/core/.oxlintrc.jsonc b/packages/core/.oxlintrc.jsonc
index 10c46209..ef5e146b 100644
--- a/packages/core/.oxlintrc.jsonc
+++ b/packages/core/.oxlintrc.jsonc
@@ -8,6 +8,7 @@
   "rules": {
     // React 19's JSX Transform handles React imports automatically
     "react/react-in-jsx-scope": "off",
+    "no-nested-ternary": "error",
   },
   "ignorePatterns": ["dist", "node_modules"],
 }
diff --git a/packages/core/src/components/csv-importer/CsvImporter.tsx b/packages/core/src/components/csv-importer/CsvImporter.tsx
index a8f52d49..13ccf0d2 100644
--- a/packages/core/src/components/csv-importer/CsvImporter.tsx
+++ b/packages/core/src/components/csv-importer/CsvImporter.tsx
@@ -239,11 +239,11 @@ function MappingStep({
                 >
                   {/* Status icon */}
                   <td className="astw:px-3 astw:py-2 astw:align-middle astw:text-center">
-                    {isMapped ? (
-                      <CheckCircle2Icon className="astw:size-5 astw:text-primary" />
-                    ) : col.required ? (
+                    {isMapped && <CheckCircle2Icon className="astw:size-5 astw:text-primary" />}
+                    {!isMapped && col.required && (
                       <CircleAlertIcon className="astw:size-5 astw:text-destructive" />
-                    ) : (
+                    )}
+                    {!isMapped && !col.required && (
                       <CircleDashedIcon className="astw:size-5 astw:text-muted-foreground/40" />
                     )}
                   </td>
@@ -741,9 +741,7 @@ export function CsvImporter<T extends CsvSchema>({
                               "astw:flex astw:size-7 astw:items-center astw:justify-center astw:rounded-full astw:text-xs astw:font-medium",
                               step === s
                                 ? "astw:bg-primary astw:text-primary-foreground"
-                                : stepIndex(step) > idx
-                                  ? "astw:bg-primary/20 astw:text-primary"
-                                  : "astw:bg-muted astw:text-muted-foreground",
+                                : stepClassForIndex(step, idx),
                             )}
                           >
                             {idx + 1}
@@ -900,3 +898,9 @@ function stepIndex(step: CsvImporterStep): number {
   const steps: CsvImporterStep[] = ["upload", "mapping", "review", "complete"];
   return steps.indexOf(step);
 }
+
+function stepClassForIndex(step: CsvImporterStep, idx: number): string {
+  return stepIndex(step) > idx
+    ? "astw:bg-primary/20 astw:text-primary"
+    : "astw:bg-muted astw:text-muted-foreground";
+}
diff --git a/packages/core/src/components/csv-importer/process-rows.ts b/packages/core/src/components/csv-importer/process-rows.ts
index 02a33b10..4a1a7560 100644
--- a/packages/core/src/components/csv-importer/process-rows.ts
+++ b/packages/core/src/components/csv-importer/process-rows.ts
@@ -1,5 +1,15 @@
 import type { CsvCellIssue, CsvColumnMapping, CsvCorrection, CsvSchema, ParsedRow } from "./types";
 
+function resolveRawValue(
+  correction: CsvCorrection | undefined,
+  colIdx: number | undefined,
+  row: string[],
+): string {
+  if (correction !== undefined) return String(correction.newValue);
+  if (colIdx !== undefined) return row[colIdx];
+  return "";
+}
+
 /** Single-pass: validate all cells and build parsed rows for onValidate. */
 export function processRows(
   rawRows: string[][],
@@ -24,12 +34,7 @@ export function processRows(
       const correction = corrections.find(
         (c) => c.row === rowIdx && c.columnKey === mapping.columnKey,
       );
-      const rawValue: string =
-        correction !== undefined
-          ? String(correction.newValue)
-          : colIdx !== undefined
-            ? row[colIdx]
-            : "";
+      const rawValue = resolveRawValue(correction, colIdx, row);
 
       const column = schema.columns.find((c) => c.key === mapping.columnKey);
       if (column?.schema) {
diff --git a/packages/core/src/components/data-table/cell-renderers.tsx b/packages/core/src/components/data-table/cell-renderers.tsx
index b6598462..9f2335e6 100644
--- a/packages/core/src/components/data-table/cell-renderers.tsx
+++ b/packages/core/src/components/data-table/cell-renderers.tsx
@@ -11,6 +11,20 @@ import type {
   NumberCellOptions,
 } from "./types";
 
+function resolveDateFormatOptions(format: string): Intl.DateTimeFormatOptions {
+  if (format === "long") return { month: "long", day: "numeric", year: "numeric" };
+  if (format === "datetime") {
+    return {
+      month: "short",
+      day: "numeric",
+      year: "numeric",
+      hour: "numeric",
+      minute: "2-digit",
+    };
+  }
+  return { month: "short", day: "numeric", year: "numeric" };
+}
+
 const PLACEHOLDER = (
   <span className="astw:text-muted-foreground" aria-hidden="true">
     —
@@ -79,7 +93,10 @@ function renderMoney<TRow extends Record<string, unknown>>(
   // `maxDecimals` raises the cap above the currency default while keeping the
   // minimum at the currency default (e.g. 2 for USD). Lets a JPY column stay
   // at 0 decimals while a USD price-detail column shows up to 4.
-  const formatOptions: Intl.NumberFormatOptions = { style: "currency", currency };
+  const formatOptions: Intl.NumberFormatOptions = {
+    style: "currency",
+    currency,
+  };
   if (options?.maxDecimals != null) {
     formatOptions.maximumFractionDigits = options.maxDecimals;
   }
@@ -101,18 +118,7 @@ function renderDate(value: unknown, options: DateCellOptions | undefined): React
   const date = toDate(value);
   if (!date) return PLACEHOLDER;
   const format = options?.dateFormat ?? "short";
-  const formatOptions: Intl.DateTimeFormatOptions =
-    format === "long"
-      ? { month: "long", day: "numeric", year: "numeric" }
-      : format === "datetime"
-        ? {
-            month: "short",
-            day: "numeric",
-            year: "numeric",
-            hour: "numeric",
-            minute: "2-digit",
-          }
-        : { month: "short", day: "numeric", year: "numeric" };
+  const formatOptions = resolveDateFormatOptions(format);
   return new Intl.DateTimeFormat(options?.locale, formatOptions).format(date);
 }
 
diff --git a/packages/core/src/components/data-table/data-table.tsx b/packages/core/src/components/data-table/data-table.tsx
index 7cd8e6ea..eb3f50a9 100644
--- a/packages/core/src/components/data-table/data-table.tsx
+++ b/packages/core/src/components/data-table/data-table.tsx
@@ -29,6 +29,12 @@ function resolveAlign<TRow extends Record<string, unknown>>(col: Column<TRow>):
   return "left";
 }
 
+function nextSortDirection(current: string | undefined): "Asc" | "Desc" | undefined {
+  if (current === "Asc") return "Desc";
+  if (current === "Desc") return undefined;
+  return "Asc";
+}
+
 // =============================================================================
 // DataTableLoaderRows (internal)
 // =============================================================================
@@ -260,13 +266,7 @@ function DataTableHeaders({ className }: { className?: string }) {
 
           const handleClick = () => {
             if (!isSortable || !onSort || !col.sort) return;
-            const nextDirection =
-              currentSort?.direction === "Asc"
-                ? "Desc"
-                : currentSort?.direction === "Desc"
-                  ? undefined
-                  : "Asc";
-            onSort(col.sort.field, nextDirection);
+            onSort(col.sort.field, nextSortDirection(currentSort?.direction));
           };
 
           const align = resolveAlign(col);
diff --git a/packages/core/src/components/layout/Layout.tsx b/packages/core/src/components/layout/Layout.tsx
index 661179fb..29e8a433 100644
--- a/packages/core/src/components/layout/Layout.tsx
+++ b/packages/core/src/components/layout/Layout.tsx
@@ -216,16 +216,12 @@ export function Layout({ columns, className, style, gap, title, actions, childre
     }
   }
 
-  const gapClass =
-    gap === undefined
-      ? "astw:gap-4"
-      : gap === 4
-        ? "astw:gap-4"
-        : gap === 6
-          ? "astw:gap-6"
-          : gap === 8
-            ? "astw:gap-8"
-            : "astw:gap-4";
+  const GAP_CLASSES: Record<number, string> = {
+    4: "astw:gap-4",
+    6: "astw:gap-6",
+    8: "astw:gap-8",
+  };
+  const gapClass = gap === undefined ? "astw:gap-4" : (GAP_CLASSES[gap] ?? "astw:gap-4");
 
   const hasLegacyHeader = !hasHeaderChild && (title || (actions != null && actions.length > 0));
 
diff --git a/packages/core/src/components/sidebar/default-sidebar.tsx b/packages/core/src/components/sidebar/default-sidebar.tsx
index de2c7109..414727e0 100644
--- a/packages/core/src/components/sidebar/default-sidebar.tsx
+++ b/packages/core/src/components/sidebar/default-sidebar.tsx
@@ -24,6 +24,15 @@ import { useT } from "@/i18n-labels";
 import { useNavItems, type NavItem } from "@/routing/navigation";
 import { cn } from "@/lib/utils";
 
+function resolveCollapsibleMode(
+  collapsible: boolean | undefined,
+  isIconMode: boolean,
+): "none" | "icon" | "offcanvas" {
+  if (!collapsible) return "none";
+  if (isIconMode) return "icon";
+  return "offcanvas";
+}
+
 // Always rendered regardless of searchSources — the palette searches routes
 // and contextual actions too, so there is always something to search.
 const SearchEntry = () => {
@@ -102,11 +111,10 @@ export const DefaultSidebar = (props: DefaultSidebarProps) => {
   );
   const DefaultFooter = null;
 
+  const collapsibleMode = resolveCollapsibleMode(collapsible, isIconMode);
+
   return (
-    <Sidebar
-      variant="inset"
-      collapsible={!collapsible ? "none" : isIconMode ? "icon" : "offcanvas"}
-    >
+    <Sidebar variant="inset" collapsible={collapsibleMode}>
       {!isIconMode && (
         <div className="astw:flex astw:justify-between astw:items-center">
           {props.header ?? DefaultHeader}
diff --git a/packages/core/src/components/tabs.tsx b/packages/core/src/components/tabs.tsx
index 4afe385f..baa6e06d 100644
--- a/packages/core/src/components/tabs.tsx
+++ b/packages/core/src/components/tabs.tsx
@@ -5,6 +5,20 @@ import { cn } from "@/lib/utils";
 
 type TabsVariant = "default" | "line" | "capsule";
 
+const LIST_VARIANT_CLASSES: Record<TabsVariant, string> = {
+  line: "astw:h-9 astw:gap-2",
+  capsule: "astw:h-10 astw:gap-0.5 astw:rounded-md astw:bg-muted astw:p-1",
+  default: "astw:text-muted-foreground astw:h-9 astw:gap-1",
+};
+
+const TAB_VARIANT_CLASSES: Record<TabsVariant, string> = {
+  line: "astw:px-3 astw:py-1.5 astw:-mb-px astw:border-b-2 astw:border-transparent astw:data-active:border-primary astw:data-active:text-foreground",
+  capsule:
+    "astw:rounded-md astw:px-3 astw:py-1.5 astw:data-active:bg-background astw:data-active:text-foreground astw:data-active:shadow-sm",
+  default:
+    "astw:rounded-md astw:px-3 astw:py-1 astw:data-active:bg-muted astw:data-active:text-foreground",
+};
+
 const TabsVariantContext = React.createContext<TabsVariant>("default");
 
 // Only the props relevant to the Tabs abstraction are picked from BaseTabs.Root.
@@ -55,11 +69,7 @@ function List({ className, children, ...props }: React.ComponentProps<typeof Bas
       data-slot="tabs-list"
       className={cn(
         "astw:relative astw:inline-flex astw:items-center astw:justify-center",
-        variant === "line"
-          ? "astw:h-9 astw:gap-2"
-          : variant === "capsule"
-            ? "astw:h-10 astw:gap-0.5 astw:rounded-md astw:bg-muted astw:p-1"
-            : "astw:text-muted-foreground astw:h-9 astw:gap-1",
+        LIST_VARIANT_CLASSES[variant],
         className,
       )}
       {...props}
@@ -81,11 +91,7 @@ function Tab({ className, children, ...props }: React.ComponentProps<typeof Base
         "astw:text-muted-foreground",
         "astw:focus-visible:outline-ring/70 astw:focus-visible:ring-ring/50 astw:focus-visible:outline-1 astw:focus-visible:ring-[3px]",
         "astw:data-disabled:pointer-events-none astw:data-disabled:opacity-50",
-        variant === "line"
-          ? "astw:px-3 astw:py-1.5 astw:-mb-px astw:border-b-2 astw:border-transparent astw:data-active:border-primary astw:data-active:text-foreground"
-          : variant === "capsule"
-            ? "astw:rounded-md astw:px-3 astw:py-1.5 astw:data-active:bg-background astw:data-active:text-foreground astw:data-active:shadow-sm"
-            : "astw:rounded-md astw:px-3 astw:py-1 astw:data-active:bg-muted astw:data-active:text-foreground",
+        TAB_VARIANT_CLASSES[variant],
         className,
       )}
       {...props}