diff --git a/cypress/src/components/treemap/shared.ts b/cypress/src/components/treemap/shared.ts
index 3c5b427c2b..d0b686c0c7 100644
--- a/cypress/src/components/treemap/shared.ts
+++ b/cypress/src/components/treemap/shared.ts
@@ -1,7 +1,7 @@
 export interface Datum {
     id: string
     value?: number
-    children?: Datum[]
+    children?: readonly Datum[]
 }
 
 export const defaultData: Datum = {
diff --git a/packages/treemap/src/TreeMapCanvas.tsx b/packages/treemap/src/TreeMapCanvas.tsx
index 987e9ed1ad..508c727372 100644
--- a/packages/treemap/src/TreeMapCanvas.tsx
+++ b/packages/treemap/src/TreeMapCanvas.tsx
@@ -26,7 +26,7 @@ import { ComputedNode, DefaultTreeMapDatum, TreeMapCanvasProps, TreeMapCommonPro
 import { canvasDefaultProps } from './defaults'
 
 const findNodeUnderCursor = <Datum extends object>(
-    nodes: ComputedNode<Datum>[],
+    nodes: readonly ComputedNode<Datum>[],
     margin: Margin,
     x: number,
     y: number
diff --git a/packages/treemap/src/TreeMapNodes.tsx b/packages/treemap/src/TreeMapNodes.tsx
index 4664595adc..82c984e8b7 100644
--- a/packages/treemap/src/TreeMapNodes.tsx
+++ b/packages/treemap/src/TreeMapNodes.tsx
@@ -52,7 +52,7 @@ const getEndingAnimatedNodeProps = <Datum extends object>(
 }
 
 interface TreeMapNodesProps<Datum extends object> {
-    nodes: ComputedNode<Datum>[]
+    nodes: readonly ComputedNode<Datum>[]
     nodeComponent: NodeComponent<Datum>
     borderWidth: TreeMapCommonProps<Datum>['borderWidth']
     enableLabel: TreeMapCommonProps<Datum>['enableLabel']
diff --git a/packages/treemap/src/hooks.ts b/packages/treemap/src/hooks.ts
index 3831ee8cab..ff82700a1d 100644
--- a/packages/treemap/src/hooks.ts
+++ b/packages/treemap/src/hooks.ts
@@ -180,7 +180,7 @@ export const useTreeMap = <Datum extends object = DefaultTreeMapDatum>({
                 const node = {
                     id: getIdentity(rawNode.data),
                     path,
-                    pathComponents,
+                    pathComponents: pathComponents as readonly string[],
                     data: omit(rawNode.data, 'children'),
                     x: rawNode.x0,
                     y: rawNode.y0,
@@ -269,7 +269,7 @@ export const useTreeMap = <Datum extends object = DefaultTreeMapDatum>({
 }
 
 export const useInteractiveTreeMapNodes = <Datum extends object>(
-    nodes: ComputedNode<Datum>[],
+    nodes: readonly ComputedNode<Datum>[],
     {
         isInteractive,
         onMouseEnter,
diff --git a/packages/treemap/src/types.ts b/packages/treemap/src/types.ts
index b8ffe9b175..1d591c5c78 100644
--- a/packages/treemap/src/types.ts
+++ b/packages/treemap/src/types.ts
@@ -15,13 +15,13 @@ import { TileType } from './tiling'
 export interface DefaultTreeMapDatum {
     id: string
     value?: number
-    children?: DefaultTreeMapDatum[]
+    children?: readonly DefaultTreeMapDatum[]
 }
 
 export interface ComputedNode<Datum extends object> {
     id: string
     path: string
-    pathComponents: string[]
+    pathComponents: readonly string[]
     data: Omit<Datum, 'children'>
     x: number
     y: number
@@ -93,7 +93,7 @@ export type TooltipComponent<Datum extends object> = FunctionComponent<TooltipPr
 export type LayerId = 'nodes'
 
 export interface CustomLayerProps<Datum extends object> {
-    nodes: ComputedNode<Datum>[]
+    nodes: readonly ComputedNode<Datum>[]
 }
 export type CustomSvgLayer<Datum extends object> = FunctionComponent<CustomLayerProps<Datum>>
 export type CustomHtmlLayer<Datum extends object> = FunctionComponent<CustomLayerProps<Datum>>
@@ -176,14 +176,14 @@ export type TreeMapSvgProps<Datum extends object> = Partial<TreeMapCommonProps<D
     Dimensions &
     SvgDefsAndFill<ComputedNode<Datum>> & {
         nodeComponent?: NodeComponent<Datum>
-        layers?: (LayerId | CustomSvgLayer<Datum>)[]
+        layers?: readonly (LayerId | CustomSvgLayer<Datum>)[]
     }
 
 export type TreeMapHtmlProps<Datum extends object> = Partial<TreeMapCommonProps<Datum>> &
     TreeMapDataProps<Datum> &
     Dimensions & {
         nodeComponent?: NodeComponent<Datum>
-        layers?: (LayerId | CustomHtmlLayer<Datum>)[]
+        layers?: readonly (LayerId | CustomHtmlLayer<Datum>)[]
     }
 
 export type TreeMapCanvasProps<Datum extends object> = Partial<
@@ -201,6 +201,6 @@ export type TreeMapCanvasProps<Datum extends object> = Partial<
 > &
     TreeMapDataProps<Datum> &
     Dimensions & {
-        layers?: (LayerId | CustomCanvasLayer<Datum>)[]
+        layers?: readonly (LayerId | CustomCanvasLayer<Datum>)[]
         pixelRatio?: number
     }