diff --git a/client/src/actions/embedding.js b/client/src/actions/embedding.js
index 555c69ab..5e882160 100644
--- a/client/src/actions/embedding.js
+++ b/client/src/actions/embedding.js
@@ -5,6 +5,23 @@ action creators related to embeddings choice
 import { AnnoMatrixObsCrossfilter } from "../annoMatrix";
 import { _setEmbeddingSubset } from "../util/stateManager/viewStackHelpers";
 
+export async function _switchEmbedding(prevAnnoMatrix, newEmbeddingName) {
+  /*
+  DRY helper used by this and reembedding action creators
+  */
+  const base = prevAnnoMatrix.base();
+  const embeddingDf = await base.fetch("emb", newEmbeddingName);
+  const annoMatrix = _setEmbeddingSubset(prevAnnoMatrix, embeddingDf);
+  const obsCrossfilter = await new AnnoMatrixObsCrossfilter(annoMatrix).select(
+    "emb",
+    newEmbeddingName,
+    {
+      mode: "all",
+    }
+  );
+  return [annoMatrix, obsCrossfilter];
+}
+
 export const layoutChoiceAction = (newLayoutChoice) => async (
   dispatch,
   getState
@@ -14,15 +31,9 @@ export const layoutChoiceAction = (newLayoutChoice) => async (
   layout.
   */
   const { annoMatrix: prevAnnoMatrix } = getState();
-
-  const embeddingDf = await prevAnnoMatrix.base().fetch("emb", newLayoutChoice);
-  const annoMatrix = _setEmbeddingSubset(prevAnnoMatrix, embeddingDf);
-  const obsCrossfilter = await new AnnoMatrixObsCrossfilter(annoMatrix).select(
-    "emb",
-    newLayoutChoice,
-    {
-      mode: "all",
-    }
+  const [annoMatrix, obsCrossfilter] = await _switchEmbedding(
+    prevAnnoMatrix,
+    newLayoutChoice
   );
   dispatch({
     type: "set layout choice",
diff --git a/client/src/actions/reembed.js b/client/src/actions/reembed.js
index 43b38e1f..2212f380 100644
--- a/client/src/actions/reembed.js
+++ b/client/src/actions/reembed.js
@@ -1,10 +1,10 @@
 import { API } from "../globals";
-import { MatrixFBS } from "../util/stateManager";
 import {
   postNetworkErrorToast,
   postAsyncSuccessToast,
   postAsyncFailureToast,
 } from "../components/framework/toasters";
+import { _switchEmbedding } from "./embedding";
 
 function abortableFetch(request, opts, timeout = 0) {
   const controller = new AbortController();
@@ -24,7 +24,7 @@ function abortableFetch(request, opts, timeout = 0) {
 
 async function doReembedFetch(dispatch, getState) {
   const state = getState();
-  let cells = state.world.obsAnnotations.rowIndex.labels();
+  let cells = state.annoMatrix.rowIndex.labels();
 
   // These lines ensure that we convert any TypedArray to an Array.
   // This is necessary because JSON.stringify() does some very strange
@@ -54,10 +54,7 @@ async function doReembedFetch(dispatch, getState) {
   });
   const res = await af.ready();
 
-  if (
-    res.ok &&
-    res.headers.get("Content-Type").includes("application/octet-stream")
-  ) {
+  if (res.ok && res.headers.get("Content-Type").includes("application/json")) {
     return res;
   }
 
@@ -67,7 +64,6 @@ async function doReembedFetch(dispatch, getState) {
   if (body && body.length > 0) {
     msg = `${msg} -- ${body}`;
   }
-  postNetworkErrorToast(msg);
   throw new Error(msg);
 }
 
@@ -78,17 +74,24 @@ export function requestReembed() {
   return async (dispatch, getState) => {
     try {
       const res = await doReembedFetch(dispatch, getState);
-      const schema = JSON.parse(res.headers.get("CxG-Schema"));
-      const buffer = await res.arrayBuffer();
-      const df = MatrixFBS.matrixFBSToDataframe(buffer);
+      const schema = await res.json();
       dispatch({
         type: "reembed: request completed",
       });
+
+      const { annoMatrix: prevAnnoMatrix } = getState();
+      const base = prevAnnoMatrix.base().addEmbedding(schema);
+      const [annoMatrix, obsCrossfilter] = await _switchEmbedding(
+        base,
+        schema.name
+      );
       dispatch({
         type: "reembed: add reembedding",
-        embedding: df,
         schema,
+        annoMatrix,
+        obsCrossfilter,
       });
+
       postAsyncSuccessToast("Re-embedding has completed.");
     } catch (error) {
       dispatch({
@@ -103,13 +106,3 @@ export function requestReembed() {
     }
   };
 }
-
-/* disabled until reimplementation occurs
-export function reembedResetWorldToUniverse(dispatch, getState) {
-  const { reembedController } = getState();
-  if (reembedController.pendingFetch) reembedController.pendingFetch.abort();
-  dispatch({
-    type: "reembed: clear all reembeddings",
-  });
-}
-*/
diff --git a/client/src/annoMatrix/annoMatrix.js b/client/src/annoMatrix/annoMatrix.js
index 15ddb008..092d9007 100644
--- a/client/src/annoMatrix/annoMatrix.js
+++ b/client/src/annoMatrix/annoMatrix.js
@@ -397,6 +397,19 @@ export default class AnnoMatrix {
     _subclassResponsibility();
   }
 
+  // eslint-disable-next-line class-methods-use-this, no-unused-vars -- make sure subclass implements
+  addEmbedding(colSchema) {
+    /*
+    Add a new obs embedding to the AnnoMatrix, with provided schema.
+    Returns a new annomatrix.
+
+    Typical use will be to add a re-embedding that the server has calculated.
+
+    Will throw if the column schema is invalid (eg, duplicate name).
+    */
+    _subclassResponsibility();
+  }
+
   /**
    ** Private interfaces below.
    **/
diff --git a/client/src/annoMatrix/crossfilter.js b/client/src/annoMatrix/crossfilter.js
index b3972978..f9f5bc53 100644
--- a/client/src/annoMatrix/crossfilter.js
+++ b/client/src/annoMatrix/crossfilter.js
@@ -118,6 +118,11 @@ export default class AnnoMatrixObsCrossfilter {
     return new AnnoMatrixObsCrossfilter(annoMatrix, obsCrossfilter);
   }
 
+  addEmbedding(colSchema) {
+    const annoMatrix = this.annoMatrix.addEmbedding(colSchema);
+    return new AnnoMatrixObsCrossfilter(annoMatrix, this.obsCrossfilter);
+  }
+
   /**
   Selection state - API is identical to ImmutableTypedCrossfilter, as these
   are just wrappers to lazy create indices.
diff --git a/client/src/annoMatrix/loader.js b/client/src/annoMatrix/loader.js
index e10e3ee1..0b5fedcf 100644
--- a/client/src/annoMatrix/loader.js
+++ b/client/src/annoMatrix/loader.js
@@ -6,6 +6,7 @@ import {
   removeObsAnnoColumn,
   addObsAnnoCategory,
   removeObsAnnoCategory,
+  addObsLayout,
 } from "../util/stateManager/schemaHelpers";
 import { isArrayOrTypedArray } from "../util/typeHelpers";
 import { _whereCacheCreate } from "./whereCache";
@@ -47,9 +48,9 @@ export default class AnnoMatrixLoader extends AnnoMatrix {
     const colSchema = _getColumnSchema(this.schema, "obs", col);
     _writableCategoryTypeCheck(colSchema); // throws on error
 
-    const o = this._clone();
-    o.schema = addObsAnnoCategory(this.schema, col, category);
-    return o;
+    const newAnnoMatrix = this._clone();
+    newAnnoMatrix.schema = addObsAnnoCategory(this.schema, col, category);
+    return newAnnoMatrix;
   }
 
   async removeObsAnnoCategory(col, category, unassignedCategory) {
@@ -59,13 +60,17 @@ export default class AnnoMatrixLoader extends AnnoMatrix {
     const colSchema = _getColumnSchema(this.schema, "obs", col);
     _writableCategoryTypeCheck(colSchema); // throws on error
 
-    const o = await this.resetObsColumnValues(
+    const newAnnoMatrix = await this.resetObsColumnValues(
       col,
       category,
       unassignedCategory
     );
-    o.schema = removeObsAnnoCategory(o.schema, col, category);
-    return o;
+    newAnnoMatrix.schema = removeObsAnnoCategory(
+      newAnnoMatrix.schema,
+      col,
+      category
+    );
+    return newAnnoMatrix;
   }
 
   dropObsColumn(col) {
@@ -75,10 +80,10 @@ export default class AnnoMatrixLoader extends AnnoMatrix {
     const colSchema = _getColumnSchema(this.schema, "obs", col);
     _writableCheck(colSchema); // throws on error
 
-    const o = this._clone();
-    o._cache.obs = this._cache.obs.dropCol(col);
-    o.schema = removeObsAnnoColumn(this.schema, col);
-    return o;
+    const newAnnoMatrix = this._clone();
+    newAnnoMatrix._cache.obs = this._cache.obs.dropCol(col);
+    newAnnoMatrix.schema = removeObsAnnoColumn(this.schema, col);
+    return newAnnoMatrix;
   }
 
   addObsColumn(colSchema, Ctor, value) {
@@ -98,7 +103,7 @@ export default class AnnoMatrixLoader extends AnnoMatrix {
       throw new Error("column already exists");
     }
 
-    const o = this._clone();
+    const newAnnoMatrix = this._clone();
     let data;
     if (isArrayOrTypedArray(value)) {
       if (value.constructor !== Ctor)
@@ -109,10 +114,13 @@ export default class AnnoMatrixLoader extends AnnoMatrix {
     } else {
       data = new Ctor(this.nObs).fill(value);
     }
-    o._cache.obs = this._cache.obs.withCol(colName, data);
-    _normalizeCategoricalSchema(colSchema, o._cache.obs.col(colName));
-    o.schema = addObsAnnoColumn(this.schema, colName, colSchema);
-    return o;
+    newAnnoMatrix._cache.obs = this._cache.obs.withCol(colName, data);
+    _normalizeCategoricalSchema(
+      colSchema,
+      newAnnoMatrix._cache.obs.col(colName)
+    );
+    newAnnoMatrix.schema = addObsAnnoColumn(this.schema, colName, colSchema);
+    return newAnnoMatrix;
   }
 
   renameObsColumn(oldCol, newCol) {
@@ -155,13 +163,13 @@ export default class AnnoMatrixLoader extends AnnoMatrix {
       data[idx] = value;
     }
 
-    const o = this._clone();
-    o._cache.obs = this._cache.obs.replaceColData(col, data);
+    const newAnnoMatrix = this._clone();
+    newAnnoMatrix._cache.obs = this._cache.obs.replaceColData(col, data);
     const { categories } = colSchema;
     if (!categories?.includes(value)) {
-      o.schema = addObsAnnoCategory(this.schema, col, value);
+      newAnnoMatrix.schema = addObsAnnoCategory(this.schema, col, value);
     }
-    return o;
+    return newAnnoMatrix;
   }
 
   async resetObsColumnValues(col, oldValue, newValue) {
@@ -185,13 +193,27 @@ export default class AnnoMatrixLoader extends AnnoMatrix {
       if (data[i] === oldValue) data[i] = newValue;
     }
 
-    const o = this._clone();
-    o._cache.obs = this._cache.obs.replaceColData(col, data);
+    const newAnnoMatrix = this._clone();
+    newAnnoMatrix._cache.obs = this._cache.obs.replaceColData(col, data);
     const { categories } = colSchema;
     if (!categories?.includes(newValue)) {
-      o.schema = addObsAnnoCategory(this.schema, col, newValue);
+      newAnnoMatrix.schema = addObsAnnoCategory(this.schema, col, newValue);
     }
-    return o;
+    return newAnnoMatrix;
+  }
+
+  addEmbedding(colSchema) {
+    /*
+    add new layout to the obs embeddings
+    */
+    const { name: colName } = colSchema;
+    if (_getColumnSchema(this.schema, "emb", colName)) {
+      throw new Error("column already exists");
+    }
+
+    const newAnnoMatrix = this._clone();
+    newAnnoMatrix.schema = addObsLayout(this.schema, colSchema);
+    return newAnnoMatrix;
   }
 
   /**
diff --git a/client/src/annoMatrix/views.js b/client/src/annoMatrix/views.js
index f97e05a0..5b9b9c26 100644
--- a/client/src/annoMatrix/views.js
+++ b/client/src/annoMatrix/views.js
@@ -17,59 +17,74 @@ class AnnoMatrixView extends AnnoMatrix {
   }
 
   addObsAnnoCategory(col, category) {
-    const o = this._clone();
-    o.viewOf = this.viewOf.addObsAnnoCategory(col, category);
-    o.schema = o.viewOf.schema;
-    return o;
+    const newAnnoMatrix = this._clone();
+    newAnnoMatrix.viewOf = this.viewOf.addObsAnnoCategory(col, category);
+    newAnnoMatrix.schema = newAnnoMatrix.viewOf.schema;
+    return newAnnoMatrix;
   }
 
   async removeObsAnnoCategory(col, category, unassignedCategory) {
-    const o = this._clone();
-    o.viewOf = await this.viewOf.removeObsAnnoCategory(
+    const newAnnoMatrix = this._clone();
+    newAnnoMatrix.viewOf = await this.viewOf.removeObsAnnoCategory(
       col,
       category,
       unassignedCategory
     );
-    o.schema = o.viewOf.schema;
-    return o;
+    newAnnoMatrix.schema = newAnnoMatrix.viewOf.schema;
+    return newAnnoMatrix;
   }
 
   dropObsColumn(col) {
-    const o = this._clone();
-    o.viewOf = this.viewOf.dropObsColumn(col);
-    o._cache.obs = this._cache.obs.dropCol(col);
-    o.schema = o.viewOf.schema;
-    return o;
+    const newAnnoMatrix = this._clone();
+    newAnnoMatrix.viewOf = this.viewOf.dropObsColumn(col);
+    newAnnoMatrix._cache.obs = this._cache.obs.dropCol(col);
+    newAnnoMatrix.schema = newAnnoMatrix.viewOf.schema;
+    return newAnnoMatrix;
   }
 
   addObsColumn(colSchema, Ctor, value) {
-    const o = this._clone();
-    o.viewOf = this.viewOf.addObsColumn(colSchema, Ctor, value);
-    o.schema = o.viewOf.schema;
-    return o;
+    const newAnnoMatrix = this._clone();
+    newAnnoMatrix.viewOf = this.viewOf.addObsColumn(colSchema, Ctor, value);
+    newAnnoMatrix.schema = newAnnoMatrix.viewOf.schema;
+    return newAnnoMatrix;
   }
 
   renameObsColumn(oldCol, newCol) {
-    const o = this._clone();
-    o.viewOf = this.viewOf.renameObsColumn(oldCol, newCol);
-    o.schema = o.viewOf.schema;
-    return o;
+    const newAnnoMatrix = this._clone();
+    newAnnoMatrix.viewOf = this.viewOf.renameObsColumn(oldCol, newCol);
+    newAnnoMatrix.schema = newAnnoMatrix.viewOf.schema;
+    return newAnnoMatrix;
   }
 
   async setObsColumnValues(col, rowLabels, value) {
-    const o = this._clone();
-    o.viewOf = await this.viewOf.setObsColumnValues(col, rowLabels, value);
-    o._cache.obs = this._cache.obs.dropCol(col);
-    o.schema = o.viewOf.schema;
-    return o;
+    const newAnnoMatrix = this._clone();
+    newAnnoMatrix.viewOf = await this.viewOf.setObsColumnValues(
+      col,
+      rowLabels,
+      value
+    );
+    newAnnoMatrix._cache.obs = this._cache.obs.dropCol(col);
+    newAnnoMatrix.schema = newAnnoMatrix.viewOf.schema;
+    return newAnnoMatrix;
   }
 
   async resetObsColumnValues(col, oldValue, newValue) {
-    const o = this._clone();
-    o.viewOf = await this.viewOf.resetObsColumnValues(col, oldValue, newValue);
-    o._cache.obs = this._cache.obs.dropCol(col);
-    o.schema = o.viewOf.schema;
-    return o;
+    const newAnnoMatrix = this._clone();
+    newAnnoMatrix.viewOf = await this.viewOf.resetObsColumnValues(
+      col,
+      oldValue,
+      newValue
+    );
+    newAnnoMatrix._cache.obs = this._cache.obs.dropCol(col);
+    newAnnoMatrix.schema = newAnnoMatrix.viewOf.schema;
+    return newAnnoMatrix;
+  }
+
+  addEmbedding(colSchema) {
+    const newAnnoMatrix = this._clone();
+    newAnnoMatrix.viewOf = this.viewOf.addEmbedding(colSchema);
+    newAnnoMatrix.schema = newAnnoMatrix.viewOf.schema;
+    return newAnnoMatrix;
   }
 }
 
diff --git a/client/src/components/embedding/index.js b/client/src/components/embedding/index.js
index b71ae1a0..d4c7562c 100644
--- a/client/src/components/embedding/index.js
+++ b/client/src/components/embedding/index.js
@@ -101,7 +101,7 @@ export default Embedding;
 
 const loadAllEmbeddingCounts = async ({ annoMatrix, available }) => {
   const embeddings = await Promise.all(
-    available.map((name) => annoMatrix.fetch("emb", name))
+    available.map((name) => annoMatrix.base().fetch("emb", name))
   );
   return available.map((name, idx) => ({
     embeddingName: name,
diff --git a/client/src/components/menubar/index.js b/client/src/components/menubar/index.js
index 63d30b90..27e6ba7f 100644
--- a/client/src/components/menubar/index.js
+++ b/client/src/components/menubar/index.js
@@ -10,6 +10,7 @@ import InformationMenu from "./infoMenu";
 import Subset from "./subset";
 import UndoRedoReset from "./undoRedo";
 import DiffexpButtons from "./diffexpButtons";
+import Reembedding from "./reembedding";
 import { getEmbSubsetView } from "../../util/stateManager/viewStackHelpers";
 
 @connect((state) => {
@@ -49,6 +50,8 @@ import { getEmbSubsetView } from "../../util/stateManager/viewStackHelpers";
     tosURL: state.config?.parameters?.["about_legal_tos"],
     privacyURL: state.config?.parameters?.["about_legal_privacy"],
     categoricalSelection: state.categoricalSelection,
+    enableReembedding:
+      state.config?.parameters?.["enable-reembedding"] ?? false,
   };
 })
 class MenuBar extends React.PureComponent {
@@ -214,6 +217,7 @@ class MenuBar extends React.PureComponent {
       colorAccessor,
       subsetPossible,
       subsetResetPossible,
+      enableReembedding,
     } = this.props;
     const { pendingClipPercentiles } = this.state;
 
@@ -266,6 +270,7 @@ class MenuBar extends React.PureComponent {
             this.handleClipPercentileMinValueChange
           }
         />
+        {enableReembedding ? <Reembedding /> : null}
         <Tooltip
           content="When a category is colored by, show labels on the graph"
           position="bottom"
diff --git a/client/src/components/menubar/reembedding.js b/client/src/components/menubar/reembedding.js
new file mode 100644
index 00000000..07124a67
--- /dev/null
+++ b/client/src/components/menubar/reembedding.js
@@ -0,0 +1,40 @@
+import React from "react";
+import { connect } from "react-redux";
+import { AnchorButton, ButtonGroup, Tooltip } from "@blueprintjs/core";
+import * as globals from "../../globals";
+import actions from "../../actions";
+import styles from "./menubar.css";
+
+@connect((state) => ({
+  reembedController: state.reembedController,
+  annoMatrix: state.annoMatrix,
+}))
+class Reembedding extends React.PureComponent {
+  render() {
+    const { dispatch, annoMatrix, reembedController } = this.props;
+    const loading = !!reembedController?.pendingFetch;
+    const disabled = annoMatrix.nObs === annoMatrix.schema.dataframe.nObs;
+    const tipContent = disabled
+      ? "Subset cells first, then click to recompute UMAP embedding."
+      : "Click to recompute UMAP embedding on the current cell subset.";
+
+    return (
+      <ButtonGroup className={styles.menubarButton}>
+        <Tooltip
+          content={tipContent}
+          position="bottom"
+          hoverOpenDelay={globals.tooltipHoverOpenDelay}
+        >
+          <AnchorButton
+            icon="new-object"
+            disabled={disabled}
+            onClick={() => dispatch(actions.requestReembed())}
+            loading={loading}
+          />
+        </Tooltip>
+      </ButtonGroup>
+    );
+  }
+}
+
+export default Reembedding;
diff --git a/client/src/reducers/index.js b/client/src/reducers/index.js
index d910cef0..76d60f0c 100644
--- a/client/src/reducers/index.js
+++ b/client/src/reducers/index.js
@@ -18,7 +18,7 @@ import autosave from "./autosave";
 import ontology from "./ontology";
 import centroidLabels from "./centroidLabels";
 import pointDialation from "./pointDilation";
-import { reembedController, reembedding } from "./reembed";
+import { reembedController } from "./reembed";
 import { gcMiddleware as annoMatrixGC } from "../annoMatrix";
 
 import undoableConfig from "./undoableConfig";
@@ -30,7 +30,6 @@ const Reducer = undoable(
     ["obsCrossfilter", obsCrossfilter],
     ["ontology", ontology],
     ["annotations", annotations],
-    ["reembedding", reembedding],
     ["layoutChoice", layoutChoice],
     ["categoricalSelection", categoricalSelection],
     ["continuousSelection", continuousSelection],
@@ -55,7 +54,6 @@ const Reducer = undoable(
     "layoutChoice",
     "centroidLabels",
     "annotations",
-    "reembedding",
   ],
   undoableConfig
 );
diff --git a/client/src/reducers/layoutChoice.js b/client/src/reducers/layoutChoice.js
index 48cff07e..14aa3f73 100644
--- a/client/src/reducers/layoutChoice.js
+++ b/client/src/reducers/layoutChoice.js
@@ -48,27 +48,15 @@ const LayoutChoice = (
     }
 
     case "reembed: add reembedding": {
+      const { schema } = nextSharedState.annoMatrix;
       const { name } = action.schema;
       const available = Array.from(new Set(state.available).add(name));
+      const currentDimNames = schema.layout.obsByName[name].dims;
       return {
         ...state,
         available,
-      };
-    }
-
-    case "reembed: clear all reembeddings": {
-      const { annoMatrix } = nextSharedState;
-      const { current } = state;
-      const dflt = setToDefaultLayout(annoMatrix.schema);
-      if (dflt.available.includes(current)) {
-        return {
-          ...state,
-          available: dflt.available,
-        };
-      }
-      return {
-        ...state,
-        ...dflt,
+        current: name,
+        currentDimNames,
       };
     }
 
diff --git a/client/src/reducers/reembed.js b/client/src/reducers/reembed.js
index a12a1e9b..02f649dc 100644
--- a/client/src/reducers/reembed.js
+++ b/client/src/reducers/reembed.js
@@ -27,38 +27,3 @@ export const reembedController = (
     }
   }
 };
-
-/*
-actual reembedding data is part of the undo/redo history
-*/
-export const reembedding = (
-  state = {
-    reembeddings: new Map(),
-  },
-  action
-) => {
-  switch (action.type) {
-    case "reembed: add reembedding": {
-      const { schema, embedding } = action;
-      const { name } = schema.name;
-      const { reembeddings } = state;
-      return {
-        ...state,
-        reembeddings: new Map(reembeddings).set(name, {
-          name,
-          schema,
-          embedding,
-        }),
-      };
-    }
-    case "reembed: clear all reembeddings": {
-      return {
-        ...state,
-        reembeddings: new Map(),
-      };
-    }
-    default: {
-      return state;
-    }
-  }
-};
diff --git a/server/common/rest.py b/server/common/rest.py
index 0a0c2b50..b2e30305 100644
--- a/server/common/rest.py
+++ b/server/common/rest.py
@@ -304,10 +304,6 @@ def layout_obs_put(request, data_adaptor):
     if not data_adaptor.dataset_config.embeddings__enable_reembedding:
         return abort(HTTPStatus.NOT_IMPLEMENTED)
 
-    preferred_mimetype = request.accept_mimetypes.best_match(["application/octet-stream"])
-    if preferred_mimetype != "application/octet-stream":
-        return abort(HTTPStatus.NOT_ACCEPTABLE)
-
     args = request.get_json()
     filter = args["filter"] if args else None
     if not filter:
@@ -315,17 +311,9 @@ def layout_obs_put(request, data_adaptor):
     method = args["method"] if args else "umap"
 
     try:
-        schema, fbs = data_adaptor.compute_embedding(method, filter)
-        return make_response(
-            fbs,
-            HTTPStatus.OK,
-            {
-                "Content-Type": "application/octet-stream",
-                "CxG-Schema": json.dumps(schema),
-                "Access-Control-Expose-Headers": "CxG-Schema",
-            },
-        )
+        schema = data_adaptor.compute_embedding(method, filter)
+        return make_response(jsonify(schema), HTTPStatus.OK, {"Content-Type": "application/json"})
     except NotImplementedError as e:
-        return abort_and_log(HTTPStatus.NOT_IMPLEMENTED, str(e), include_exc_info=True)
+        return abort_and_log(HTTPStatus.NOT_IMPLEMENTED, str(e))
     except (ValueError, DisabledFeatureError, FilterError) as e:
         return abort_and_log(HTTPStatus.BAD_REQUEST, str(e), include_exc_info=True)
diff --git a/server/compute/scanpy.py b/server/compute/scanpy.py
index cebafabd..36c2e1a9 100644
--- a/server/compute/scanpy.py
+++ b/server/compute/scanpy.py
@@ -1,4 +1,5 @@
 import importlib
+import numpy as np
 
 """
 Wrapper for various scanpy modules.  Will raise NotImplementedError if the scanpy
@@ -11,8 +12,8 @@ def get_scanpy_module():
         sc = importlib.import_module("scanpy")
         # Future: we could enforce versions here, eg, lookat sc.__version__
         return sc
-    except ModuleNotFoundError:
-        raise NotImplementedError("Please install scanpy to enable UMAP re-embedding")
+    except ModuleNotFoundError as e:
+        raise NotImplementedError("Please install scanpy to enable UMAP re-embedding") from e
     except Exception as e:
         # will capture other ImportError corner cases
         raise NotImplementedError() from e
@@ -46,4 +47,7 @@ def scanpy_umap(adata, obs_mask=None, pca_options={}, neighbors_options={}, umap
     sc.pp.neighbors(adata, **neighbors_options)
     sc.tl.umap(adata, **umap_options)
 
-    return adata.obsm["X_umap"]
+    umap = adata.obsm["X_umap"]
+    result = np.full((obs_mask.shape[0], umap.shape[1]), np.NaN)
+    result[obs_mask] = umap
+    return result
diff --git a/server/data_anndata/anndata_adaptor.py b/server/data_anndata/anndata_adaptor.py
index 69496614..f9c781ad 100644
--- a/server/data_anndata/anndata_adaptor.py
+++ b/server/data_anndata/anndata_adaptor.py
@@ -1,7 +1,6 @@
 import warnings
 
 import numpy as np
-import pandas as pd
 from pandas.core.dtypes.dtypes import CategoricalDtype
 import anndata
 from scipy import sparse
@@ -314,16 +313,15 @@ class AnndataAdaptor(DataAdaptor):
             raise FilterError("Error parsing filter")
         with ServerTiming.time("layout.compute"):
             X_umap = scanpy_umap(self.data, obs_mask)
-            normalized_layout = DataAdaptor.normalize_embedding(X_umap)
 
         # Server picks reemedding name, which must not collide with any other
-        # embedding name generated by this backed.
+        # embedding name generated by this backend.
         name = f"reembed:{method}_{datetime.now().isoformat(timespec='milliseconds')}"
         dims = [f"{name}_0", f"{name}_1"]
-        df = pd.DataFrame(normalized_layout, columns=dims)
-        fbs = encode_matrix_fbs(df, col_idx=df.columns, row_idx=None)
-        schema = {"name": name, "type": "float32", "dims": dims}
-        return (schema, fbs)
+        layout_schema = {"name": name, "type": "float32", "dims": dims}
+        self.schema["layout"]["obs"].append(layout_schema)
+        self.data.obsm[f"X_{name}"] = X_umap
+        return layout_schema
 
     def compute_diffexp_ttest(self, maskA, maskB, top_n=None, lfc_cutoff=None):
         if top_n is None:
diff --git a/server/data_common/data_adaptor.py b/server/data_common/data_adaptor.py
index 20f8b601..84ac5e64 100644
--- a/server/data_common/data_adaptor.py
+++ b/server/data_common/data_adaptor.py
@@ -71,8 +71,7 @@ class DataAdaptor(metaclass=ABCMeta):
 
     @abstractmethod
     def compute_embedding(self, method, filter):
-        """compute a new embedding on the specified obs subset, and return a
-           tuple of (schema, fbs)."""
+        """compute a new embedding on the specified obs subset, and return the embedding schema. """
         pass
 
     @abstractmethod
diff --git a/server/test/test_anndata_adaptor.py b/server/test/test_anndata_adaptor.py
index 3afe2ea3..440e9b82 100644
--- a/server/test/test_anndata_adaptor.py
+++ b/server/test/test_anndata_adaptor.py
@@ -237,14 +237,14 @@ class AdaptorTest(unittest.TestCase):
                 self.data.compute_embedding("umap", filter)
             return
 
-        (schema, fbs) = self.data.compute_embedding("umap", filter)
+        schema = self.data.compute_embedding("umap", filter)
 
         self.assertIsInstance(schema["name"], str)
         name = schema["name"]
         self.assertEqual(schema["type"], "float32")
         self.assertEqual(schema["dims"], [f"{name}_0", f"{name}_1"])
 
-        emb = decode_fbs.decode_matrix_FBS(fbs)
-        self.assertEqual(emb["n_rows"], 100)
-        self.assertEqual(emb["n_cols"], 2)
-        self.assertEqual(emb["col_idx"], [f"{name}_0", f"{name}_1"])
+        emb = self.data.data.obsm[f"X_{name}"]
+        self.assertEqual(emb.shape, (2638, 2))
+        self.assertTrue(np.isfinite(emb[0:100]).all())
+        self.assertTrue(np.isnan(emb[100:]).all())
diff --git a/server/test/test_api.py b/server/test/test_api.py
index d3ecb315..7b50c426 100644
--- a/server/test/test_api.py
+++ b/server/test/test_api.py
@@ -73,21 +73,23 @@ class EndPoints(object):
         # attempt to reembed with umap over 100 cells.
         endpoint = "layout/obs"
         url = f"{self.URL_BASE}{endpoint}"
-        header = {"Accept": "application/octet-stream"}
         data = {}
         data["filter"] = {}
         data["filter"]["obs"] = {}
         data["filter"]["obs"]["index"] = list(range(100))
         data["method"] = "umap"
-        result = self.session.put(url, headers=header, json=data)
+        result = self.session.put(url, json=data)
 
         self.assertEqual(result.status_code, HTTPStatus.OK)
-        df = decode_fbs.decode_matrix_FBS(result.content)
-        self.assertEqual(df["n_rows"], 100)
-        self.assertEqual(df["n_cols"], 2)
-        cols = list(df["col_idx"])
-        self.assertTrue(cols[0].startswith("reembed:umap_") and cols[0].endswith("_0"))
-        self.assertTrue(cols[1].startswith("reembed:umap_") and cols[1].endswith("_1"))
+        result_data = result.json()
+        self.assertIsInstance(result_data, dict)
+        self.assertEqual(result_data["type"], "float32")
+        self.assertTrue(result_data["name"].startswith("reembed:umap_"))
+        self.assertIsInstance(result_data["dims"], list)
+        self.assertEqual(len(result_data["dims"]), 2)
+        dims = result_data["dims"]
+        self.assertTrue(dims[0].startswith("reembed:umap_") and dims[0].endswith("_0"))
+        self.assertTrue(dims[1].startswith("reembed:umap_") and dims[1].endswith("_1"))
 
     def test_bad_filter(self):
         endpoint = "data/var"