diff --git a/client/__tests__/util/stateManager/worldUtil.test.js b/client/__tests__/util/stateManager/worldUtil.test.js
deleted file mode 100644
index 59ddc974..00000000
--- a/client/__tests__/util/stateManager/worldUtil.test.js
+++ /dev/null
@@ -1,62 +0,0 @@
-import {
-  countCategoryValues2D,
-  clearCaches
-} from "../../../src/util/stateManager/worldUtil";
-import * as Dataframe from "../../../src/util/dataframe";
-
-describe("WorldUtil cache management", () => {
-  test("empty", () => {
-    const count = countCategoryValues2D(
-      "a",
-      "b",
-      new Dataframe.Dataframe([0, 0], [])
-    );
-    expect(count).toMatchObject(new Map());
-    expect(count.size).toBe(0);
-  });
-
-  test("simple couts", () => {
-    const df = new Dataframe.Dataframe(
-      [3, 2],
-      [[0, 0, 1], [false, true, false]],
-      null,
-      new Dataframe.KeyIndex(["a", "b"])
-    );
-    const count = countCategoryValues2D("a", "b", df);
-    expect(count).toMatchObject(
-      new Map([
-        [0, new Map([[true, 1], [false, 1]])],
-        [1, new Map([[false, 1]])]
-      ])
-    );
-  });
-
-  test("memo cache clear", () => {
-    clearCaches();
-    const df1 = new Dataframe.Dataframe([0, 0], []);
-    const df2 = new Dataframe.Dataframe(
-      [3, 2],
-      [[0, 0, 1], [false, true, false]],
-      null,
-      new Dataframe.KeyIndex(["a", "b"])
-    );
-
-    const count1 = countCategoryValues2D("a", "b", df1);
-    const count2 = countCategoryValues2D("a", "b", df1);
-    const count3 = countCategoryValues2D("a", "b", df1.clone());
-    const count4 = countCategoryValues2D("a", "b", df2);
-
-    clearCaches();
-    const count10 = countCategoryValues2D("a", "b", df1);
-    const count11 = countCategoryValues2D("a", "b", df2);
-
-    expect(count1).toEqual(count2);
-    expect(count1).toEqual(count3);
-    expect(count1).toEqual(count10);
-    expect(count1).not.toBe(count3);
-    expect(count1).not.toBe(count10);
-
-    expect(count4).toEqual(count11);
-    expect(count4).not.toBe(count11);
-  });
-});
diff --git a/client/src/components/brushableHistogram/index.js b/client/src/components/brushableHistogram/index.js
index 5ef7adb1..58379b20 100644
--- a/client/src/components/brushableHistogram/index.js
+++ b/client/src/components/brushableHistogram/index.js
@@ -13,15 +13,21 @@ import * as globals from "../../globals";
 import actions from "../../actions";
 import { makeContinuousDimensionName } from "../../util/nameCreators";
 
-@connect(state => ({
-  world: state.world,
-  scatterplotXXaccessor: state.controls.scatterplotXXaccessor,
-  scatterplotYYaccessor: state.controls.scatterplotYYaccessor,
-  continuousSelection: state.continuousSelection,
-  differential: state.differential,
-  colorAccessor: state.colors.colorAccessor
-}))
-class HistogramBrush extends React.Component {
+@connect((state, ownProps) => {
+  const { isObs, isUserDefined, isDiffExp, field } = ownProps;
+  const myName = makeContinuousDimensionName(
+    { isObs, isUserDefined, isDiffExp },
+    field
+  );
+  return {
+    world: state.world,
+    scatterplotXXaccessor: state.controls.scatterplotXXaccessor,
+    scatterplotYYaccessor: state.controls.scatterplotYYaccessor,
+    continuousSelectionRange: state.continuousSelection[myName],
+    colorAccessor: state.colors.colorAccessor
+  };
+})
+class HistogramBrush extends React.PureComponent {
   static getColumn(world, field, clipped = true) {
     /*
     Return the underlying Dataframe column for our field.   By default,
@@ -84,7 +90,7 @@ class HistogramBrush extends React.Component {
   }
 
   componentDidUpdate(prevProps) {
-    const { field, world, continuousSelection } = this.props;
+    const { field, world } = this.props;
     const { x, y, bins, svgRef } = this._histogram;
     let { brushXselection, brushX } = this.state;
     let forceBrushUpdate = false;
@@ -112,16 +118,8 @@ class HistogramBrush extends React.Component {
     if the selection has changed, ensure that the brush correctly reflects
     the underlying selection.
     */
-    if (
-      forceBrushUpdate ||
-      continuousSelection !== prevProps.continuousSelection
-    ) {
-      const { isObs, isUserDefined, isDiffExp } = this.props;
-      const myName = makeContinuousDimensionName(
-        { isObs, isUserDefined, isDiffExp },
-        field
-      );
-      const range = continuousSelection[myName];
+    const { continuousSelectionRange: range } = this.props;
+    if (forceBrushUpdate || range !== prevProps.continuousSelectionRange) {
       if (brushXselection) {
         const selection = d3.brushSelection(brushXselection.node());
         if (!range && selection) {
@@ -417,8 +415,8 @@ class HistogramBrush extends React.Component {
           isDiffExp
             ? "histogram-diffexp"
             : isUserDefined
-              ? "histogram-user-gene"
-              : "histogram-continuous-metadata"
+            ? "histogram-user-gene"
+            : "histogram-continuous-metadata"
         }
         style={{
           padding: globals.leftSidebarSectionPadding,
diff --git a/client/src/components/categorical/categorical.js b/client/src/components/categorical/categorical.js
index da658eac..98bb8785 100644
--- a/client/src/components/categorical/categorical.js
+++ b/client/src/components/categorical/categorical.js
@@ -76,30 +76,26 @@ class Categories extends React.Component {
       >
         {/* READ ONLY CATEGORICAL FIELDS */}
         {/* this is duplicative but flat, could be abstracted */}
-        {_.map(
-          allCategoryNames,
-          catName =>
-            !schema.annotations.obsByName[catName].writable ? (
-              <Category
-                key={catName}
-                metadataField={catName}
-                createAnnoModeActive={createAnnoModeActive}
-                isUserAnno={false}
-              />
-            ) : null
+        {_.map(allCategoryNames, catName =>
+          !schema.annotations.obsByName[catName].writable ? (
+            <Category
+              key={catName}
+              metadataField={catName}
+              createAnnoModeActive={createAnnoModeActive}
+              isUserAnno={false}
+            />
+          ) : null
         )}
         {/* WRITEABLE FIELDS */}
-        {_.map(
-          allCategoryNames,
-          catName =>
-            schema.annotations.obsByName[catName].writable ? (
-              <Category
-                key={catName}
-                metadataField={catName}
-                createAnnoModeActive={createAnnoModeActive}
-                isUserAnno
-              />
-            ) : null
+        {_.map(allCategoryNames, catName =>
+          schema.annotations.obsByName[catName].writable ? (
+            <Category
+              key={catName}
+              metadataField={catName}
+              createAnnoModeActive={createAnnoModeActive}
+              isUserAnno
+            />
+          ) : null
         )}
         {writableCategoriesEnabled ? (
           <div>
diff --git a/client/src/components/graph/graph.js b/client/src/components/graph/graph.js
index c3cdbfa5..66f30416 100644
--- a/client/src/components/graph/graph.js
+++ b/client/src/components/graph/graph.js
@@ -83,7 +83,7 @@ function renderThrottle(callback) {
   graphInteractionMode: state.controls.graphInteractionMode,
   colorAccessor: state.colors.colorAccessor
 }))
-class Graph extends React.Component {
+class Graph extends React.PureComponent {
   computePointPositions = memoize((X, Y, modelTF) => {
     /*
     compute the model coordinate for each point
diff --git a/client/src/components/menubar/cellSetButtons.js b/client/src/components/menubar/cellSetButtons.js
index c9b34115..47f9a338 100644
--- a/client/src/components/menubar/cellSetButtons.js
+++ b/client/src/components/menubar/cellSetButtons.js
@@ -6,7 +6,7 @@ import { World } from "../../util/stateManager";
 import { tooltipHoverOpenDelay } from "../../globals";
 
 @connect()
-class CellSetButton extends React.Component {
+class CellSetButton extends React.PureComponent {
   set() {
     const {
       differential,
diff --git a/client/src/components/scatterplot/scatterplot.js b/client/src/components/scatterplot/scatterplot.js
index 43ad808d..781aa9b7 100644
--- a/client/src/components/scatterplot/scatterplot.js
+++ b/client/src/components/scatterplot/scatterplot.js
@@ -57,7 +57,7 @@ function createProjectionTF(viewportWidth, viewportHeight) {
     responsive: state.responsive
   };
 })
-class Scatterplot extends React.Component {
+class Scatterplot extends React.PureComponent {
   computePointPositions = memoize((X, Y, xScale, yScale) => {
     const positions = new Float32Array(2 * X.length);
     for (let i = 0, len = X.length; i < len; i += 1) {
diff --git a/client/src/reducers/controls.js b/client/src/reducers/controls.js
index e3e3f908..9a9ac531 100644
--- a/client/src/reducers/controls.js
+++ b/client/src/reducers/controls.js
@@ -2,8 +2,6 @@
 
 import _ from "lodash";
 
-import { WorldUtil } from "../util/stateManager";
-
 const Controls = (
   state = {
     // data loading flag
@@ -45,7 +43,6 @@ const Controls = (
     }
     case "initial data load complete (universe exists)": {
       /* first light - create world & other data-driven defaults */
-      WorldUtil.clearCaches();
       return {
         ...state,
         loading: false,
@@ -54,14 +51,12 @@ const Controls = (
       };
     }
     case "reset World to eq Universe": {
-      WorldUtil.clearCaches();
       return {
         ...state,
         resettingInterface: false
       };
     }
     case "set World to current selection": {
-      WorldUtil.clearCaches();
       return {
         ...state,
         loading: false,
diff --git a/client/src/util/dataframe/dataframe.js b/client/src/util/dataframe/dataframe.js
index c79a7b6d..5e2c444e 100644
--- a/client/src/util/dataframe/dataframe.js
+++ b/client/src/util/dataframe/dataframe.js
@@ -127,6 +127,7 @@ class Dataframe {
     this.__id = Dataframe.__getId();
 
     this.__compile(__columnsAccessor);
+    Object.freeze(this);
   }
 
   static __errorChecks(dims, columnarData, rowIndex, colIndex) {
@@ -269,6 +270,7 @@ class Dataframe {
     get.iget = iget;
     get.__id = __id;
 
+    Object.freeze(get);
     return get;
   }
 
@@ -288,6 +290,7 @@ class Dataframe {
       }
       return Dataframe.__compileColumn(column, getRowByOffset, getRowByLabel);
     });
+    Object.freeze(this.__columnsAccessor);
   }
 
   clone() {
diff --git a/client/src/util/stateManager/index.js b/client/src/util/stateManager/index.js
index 345ffbde..c73f9518 100644
--- a/client/src/util/stateManager/index.js
+++ b/client/src/util/stateManager/index.js
@@ -17,7 +17,6 @@ exists to support those concepts.
 export * as ColorHelpers from "./colorHelpers";
 export * as Universe from "./universe";
 export * as World from "./world";
-export * as WorldUtil from "./worldUtil";
 export * as ControlsHelpers from "./controlsHelpers";
 export * as AnnotationsHelpers from "./annotationsHelpers";
 export * as SchemaHelpers from "./schemaHelpers";
diff --git a/client/src/util/stateManager/worldUtil.js b/client/src/util/stateManager/worldUtil.js
deleted file mode 100644
index d51eb638..00000000
--- a/client/src/util/stateManager/worldUtil.js
+++ /dev/null
@@ -1,75 +0,0 @@
-/* eslint-disable import/prefer-default-export */
-import _ from "lodash";
-
-/*
-Various utility functions operating on World/Universe
-*/
-
-/*
-Count unique category values, binning first by dim1 then by dim2
-Return:
-
-Map {
-   dim1_val1: Map {
-      dim2_val1: number,
-      dim2_val2: number,
-      ...
-   },
-   ...
-}
-
-Parameters are:
-- dim1: dimension 1 name/label
-- dim2: dimension 2 name/label
-- df: dataframe containing dim1 and dim2 on the column axis
-
-*/
-function _countCategoryValues2D(dim1, dim2, df) {
-  const dimMap = new Map();
-  const col1 = df.col(dim1) ? df.col(dim1).asArray() : null;
-  const col2 = df.col(dim2) ? df.col(dim2).asArray() : null;
-  if (!col1 || !col2) {
-    return dimMap;
-  }
-
-  for (let r = 0, l = df.length; r < l; r += 1) {
-    const val1 = col1[r];
-    const val2 = col2[r];
-    let d2Map = dimMap.get(val1);
-    if (d2Map === undefined) {
-      d2Map = new Map();
-      dimMap.set(val1, d2Map);
-    }
-    let curCount = d2Map.get(val2);
-    if (curCount === undefined) {
-      curCount = 0;
-    }
-    d2Map.set(val2, curCount + 1);
-  }
-  return dimMap;
-}
-
-let __worldUtilMemoId__ = 0;
-function _memoizedId(x) {
-  if (!x.__worldUtilMemoId__) {
-    __worldUtilMemoId__ += 1;
-    x.__worldUtilMemoId__ = __worldUtilMemoId__;
-  }
-  return x.__worldUtilMemoId__;
-}
-function _countCategoryValues2DResolver(...args) {
-  const id = args[0] + args[1] + _memoizedId(args[2]);
-  return id;
-}
-
-export const countCategoryValues2D = _.memoize(
-  _countCategoryValues2D,
-  _countCategoryValues2DResolver
-);
-
-/*
-Clear any cached data within WorldUtil caches, eg, memoized functions
-*/
-export function clearCaches() {
-  countCategoryValues2D.cache.clear();
-}
diff --git a/client/src/util/typedCrossfilter/bitArray.js b/client/src/util/typedCrossfilter/bitArray.js
index 51ff809a..3db06c1c 100644
--- a/client/src/util/typedCrossfilter/bitArray.js
+++ b/client/src/util/typedCrossfilter/bitArray.js
@@ -35,6 +35,7 @@ class BitArray {
 
     this.bitmask = new Int32Array(this.width); // dimension allocation mask
     this.bitarray = new Int32Array(this.width * this.length);
+    Object.seal(this);
   }
 
   // Return the number of records that are selected, ie, have a one bit in
diff --git a/client/src/util/typedCrossfilter/crossfilter.js b/client/src/util/typedCrossfilter/crossfilter.js
index 98e9672d..d1961156 100644
--- a/client/src/util/typedCrossfilter/crossfilter.js
+++ b/client/src/util/typedCrossfilter/crossfilter.js
@@ -47,6 +47,7 @@ export default class ImmutableTypedCrossfilter {
     this.data = data;
     this.selectionCache = selectionCache; /* BitArray */
     this.dimensions = dimensions; /* name: { id, dim, name, selection } */
+    Object.preventExtensions(this);
   }
 
   size() {
@@ -94,6 +95,7 @@ export default class ImmutableTypedCrossfilter {
     }
     const DimensionType = DimTypes[type];
     const dim = new DimensionType(name, data, ...rest);
+    Object.freeze(dim);
     const dimensions = {
       ...this.dimensions,
       [name]: {