diff --git a/packages/components/src/components/DistributionChart.tsx b/packages/components/src/components/DistributionChart.tsx
index 961178ff..af644d29 100644
--- a/packages/components/src/components/DistributionChart.tsx
+++ b/packages/components/src/components/DistributionChart.tsx
@@ -5,18 +5,15 @@ import {
   distributionError,
   distributionErrorToString,
 } from "@quri/squiggle-lang";
-import { Vega, VisualizationSpec } from "react-vega";
-import * as chartSpecification from "../vega-specs/spec-distributions.json";
+import { Vega } from "react-vega";
 import { ErrorAlert } from "./Alert";
 import { useSize } from "react-use";
 import clsx from "clsx";
 
 import {
-  linearXScale,
-  logXScale,
-  linearYScale,
-  expYScale,
-} from "./DistributionVegaScales";
+  buildVegaSpec,
+  DistributionChartSpecOptions,
+} from "../lib/distributionSpecBuilder";
 import { NumberShower } from "./NumberShower";
 
 export type DistributionPlottingSettings = {
@@ -24,27 +21,26 @@ export type DistributionPlottingSettings = {
   showSummary: boolean;
   /** Whether to show the user graph controls (scale etc) */
   showControls: boolean;
-  /** Set the x scale to be logarithmic by deault */
-  logX: boolean;
-  /** Set the y scale to be exponential by deault */
-  expY: boolean;
-};
+} & DistributionChartSpecOptions;
 
 export type DistributionChartProps = {
   distribution: Distribution;
   width?: number;
   height: number;
+  actions?: boolean;
 } & DistributionPlottingSettings;
 
-export const DistributionChart: React.FC<DistributionChartProps> = ({
-  distribution,
-  height,
-  showSummary,
-  width,
-  showControls,
-  logX,
-  expY,
-}) => {
+export const DistributionChart: React.FC<DistributionChartProps> = (props) => {
+  const {
+    distribution,
+    height,
+    showSummary,
+    width,
+    showControls,
+    logX,
+    expY,
+    actions = false,
+  } = props;
   const [isLogX, setLogX] = React.useState(logX);
   const [isExpY, setExpY] = React.useState(expY);
 
@@ -64,7 +60,7 @@ export const DistributionChart: React.FC<DistributionChartProps> = ({
     const massBelow0 =
       shape.value.continuous.some((x) => x.x <= 0) ||
       shape.value.discrete.some((x) => x.x <= 0);
-    const spec = buildVegaSpec(isLogX, isExpY);
+    const spec = buildVegaSpec(props);
 
     let widthProp = width ? width : size.width;
     if (widthProp < 20) {
@@ -82,7 +78,7 @@ export const DistributionChart: React.FC<DistributionChartProps> = ({
             data={{ con: shape.value.continuous, dis: shape.value.discrete }}
             width={widthProp - 10}
             height={height}
-            actions={false}
+            actions={actions}
           />
         ) : (
           <ErrorAlert heading="Log Domain Error">
@@ -116,16 +112,6 @@ export const DistributionChart: React.FC<DistributionChartProps> = ({
   return sized;
 };
 
-function buildVegaSpec(isLogX: boolean, isExpY: boolean): VisualizationSpec {
-  return {
-    ...chartSpecification,
-    scales: [
-      isLogX ? logXScale : linearXScale,
-      isExpY ? expYScale : linearYScale,
-    ],
-  } as VisualizationSpec;
-}
-
 interface CheckBoxProps {
   label: string;
   onChange: (x: boolean) => void;
diff --git a/packages/components/src/components/SquiggleChart.tsx b/packages/components/src/components/SquiggleChart.tsx
index bfb69a4e..f9f2b368 100644
--- a/packages/components/src/components/SquiggleChart.tsx
+++ b/packages/components/src/components/SquiggleChart.tsx
@@ -44,6 +44,18 @@ export interface SquiggleChartProps {
   logX?: boolean;
   /** Set the y scale to be exponential by deault */
   expY?: boolean;
+  /** How to format numbers on the x axis */
+  tickFormat?: string;
+  /** Title of the graphed distribution */
+  title?: string;
+  /** Color of the graphed distribution */
+  color?: string;
+  /** Specify the lower bound of the x scale */
+  minX?: number;
+  /** Specify the upper bound of the x scale */
+  maxX?: number;
+  /** Whether to show vega actions to the user, so they can copy the chart spec */
+  distributionChartActions?: boolean;
 }
 
 const defaultOnChange = () => {};
@@ -65,6 +77,12 @@ export const SquiggleChart: React.FC<SquiggleChartProps> = React.memo(
     diagramStart = 0,
     diagramStop = 10,
     diagramCount = 100,
+    tickFormat,
+    minX,
+    maxX,
+    color,
+    title,
+    distributionChartActions,
   }) => {
     const result = useSquiggle({
       code,
@@ -83,6 +101,12 @@ export const SquiggleChart: React.FC<SquiggleChartProps> = React.memo(
       showSummary,
       logX,
       expY,
+      format: tickFormat,
+      minX,
+      maxX,
+      color,
+      title,
+      actions: distributionChartActions,
     };
 
     let chartSettings = {
diff --git a/packages/components/src/components/SquigglePlayground.tsx b/packages/components/src/components/SquigglePlayground.tsx
index 301d8892..534be721 100644
--- a/packages/components/src/components/SquigglePlayground.tsx
+++ b/packages/components/src/components/SquigglePlayground.tsx
@@ -18,7 +18,7 @@ import clsx from "clsx";
 
 import { defaultBindings, environment } from "@quri/squiggle-lang";
 
-import { SquiggleChart } from "./SquiggleChart";
+import { SquiggleChart, SquiggleChartProps } from "./SquiggleChart";
 import { CodeEditor } from "./CodeEditor";
 import { JsonEditor } from "./JsonEditor";
 import { ErrorAlert, SuccessAlert } from "./Alert";
@@ -27,28 +27,16 @@ import { Toggle } from "./ui/Toggle";
 import { Checkbox } from "./ui/Checkbox";
 import { StyledTab } from "./ui/StyledTab";
 
-interface PlaygroundProps {
+type PlaygroundProps = SquiggleChartProps & {
   /** The initial squiggle string to put in the playground */
   defaultCode?: string;
   /** How many pixels high is the playground */
-  height?: number;
-  /** Whether to show the types of outputs in the playground */
-  showTypes?: boolean;
-  /** Whether to show the log scale controls in the playground */
-  showControls?: boolean;
-  /** Whether to show the summary table in the playground */
-  showSummary?: boolean;
-  /** Whether to log the x coordinate on distribution charts */
-  logX?: boolean;
-  /** Whether to exp the y coordinate on distribution charts */
-  expY?: boolean;
-  /** If code is set, component becomes controlled */
-  code?: string;
   onCodeChange?(expr: string): void;
+  /* When settings change */
   onSettingsChange?(settings: any): void;
   /** Should we show the editor? */
   showEditor?: boolean;
-}
+};
 
 const schema = yup.object({}).shape({
   sampleCount: yup
@@ -82,6 +70,12 @@ const schema = yup.object({}).shape({
   showEditor: yup.boolean().required(),
   logX: yup.boolean().required(),
   expY: yup.boolean().required(),
+  tickFormat: yup.string().default(".9~s"),
+  title: yup.string(),
+  color: yup.string().default("#739ECC").required(),
+  minX: yup.number(),
+  maxX: yup.number(),
+  distributionChartActions: yup.boolean(),
   showSettingsPage: yup.boolean().default(false),
   diagramStart: yup.number().required().positive().integer().default(0).min(0),
   diagramStop: yup.number().required().positive().integer().default(10).min(0),
@@ -114,7 +108,7 @@ function InputItem<T>({
 }: {
   name: Path<T>;
   label: string;
-  type: "number";
+  type: "number" | "text" | "color";
   register: UseFormRegister<T>;
 }) {
   return (
@@ -122,7 +116,7 @@ function InputItem<T>({
       <div className="text-sm font-medium text-gray-600 mb-1">{label}</div>
       <input
         type={type}
-        {...register(name)}
+        {...register(name, { valueAsNumber: type === "number" })}
         className="form-input max-w-lg block w-full shadow-sm focus:ring-indigo-500 focus:border-indigo-500 sm:max-w-xs sm:text-sm border-gray-300 rounded-md"
       />
     </label>
@@ -202,6 +196,11 @@ const ViewSettings: React.FC<{ register: UseFormRegister<FormFields> }> = ({
             name="expY"
             label="Show y scale exponentially"
           />
+          <Checkbox
+            register={register}
+            name="distributionChartActions"
+            label="Show vega chart controls"
+          />
           <Checkbox
             register={register}
             name="showControls"
@@ -212,6 +211,36 @@ const ViewSettings: React.FC<{ register: UseFormRegister<FormFields> }> = ({
             name="showSummary"
             label="Show summary statistics"
           />
+          <InputItem
+            name="minX"
+            type="number"
+            register={register}
+            label="The minimum of the charted distribution domain"
+          />
+          <InputItem
+            name="maxX"
+            type="number"
+            register={register}
+            label="The maximum of the charted distribution domain"
+          />
+          <InputItem
+            name="title"
+            type="text"
+            register={register}
+            label="The title shown on the distribution"
+          />
+          <InputItem
+            name="tickFormat"
+            type="text"
+            register={register}
+            label="The format that the ticks are rendered"
+          />
+          <InputItem
+            name="color"
+            type="color"
+            register={register}
+            label="The color of the charted distribution"
+          />
         </div>
       </HeadedSection>
     </div>
@@ -385,6 +414,12 @@ export const SquigglePlayground: FC<PlaygroundProps> = ({
   showSummary = false,
   logX = false,
   expY = false,
+  title,
+  minX,
+  maxX,
+  color = "#739ECC",
+  tickFormat = ".9~s",
+  distributionChartActions,
   code: controlledCode,
   onCodeChange,
   onSettingsChange,
@@ -408,6 +443,12 @@ export const SquigglePlayground: FC<PlaygroundProps> = ({
       showControls,
       logX,
       expY,
+      title,
+      minX,
+      maxX,
+      color,
+      tickFormat,
+      distributionChartActions,
       showSummary,
       showEditor,
       leftSizePercent: 50,
@@ -440,15 +481,7 @@ export const SquigglePlayground: FC<PlaygroundProps> = ({
     <SquiggleChart
       code={renderedCode}
       environment={env}
-      diagramStart={Number(vars.diagramStart)}
-      diagramStop={Number(vars.diagramStop)}
-      diagramCount={Number(vars.diagramCount)}
-      height={vars.chartHeight}
-      showTypes={vars.showTypes}
-      showControls={vars.showControls}
-      showSummary={vars.showSummary}
-      logX={vars.logX}
-      expY={vars.expY}
+      {...vars}
       bindings={defaultBindings}
       jsImports={imports}
     />
@@ -496,6 +529,7 @@ export const SquigglePlayground: FC<PlaygroundProps> = ({
 
   const withoutEditor = <div className="mt-3">{tabs}</div>;
 
+  console.log(vars);
   return (
     <SquiggleContainer>
       <StyledTab.Group>
diff --git a/packages/components/src/lib/distributionSpecBuilder.ts b/packages/components/src/lib/distributionSpecBuilder.ts
new file mode 100644
index 00000000..4286dbdb
--- /dev/null
+++ b/packages/components/src/lib/distributionSpecBuilder.ts
@@ -0,0 +1,256 @@
+import { VisualizationSpec } from "react-vega";
+import type { LogScale, LinearScale, PowScale } from "vega";
+
+export type DistributionChartSpecOptions = {
+  /** Set the x scale to be logarithmic by deault */
+  logX: boolean;
+  /** Set the y scale to be exponential by deault */
+  expY: boolean;
+  /** The minimum x coordinate shown on the chart */
+  minX?: number;
+  /** The maximum x coordinate shown on the chart */
+  maxX?: number;
+  /** The color of the chart */
+  color?: string;
+  /** The title of the chart */
+  title?: string;
+  /** The formatting of the ticks */
+  format?: string;
+};
+
+export let linearXScale: LinearScale = {
+  name: "xscale",
+  clamp: true,
+  type: "linear",
+  range: "width",
+  zero: false,
+  nice: false,
+  domain: {
+    fields: [
+      {
+        data: "con",
+        field: "x",
+      },
+      {
+        data: "dis",
+        field: "x",
+      },
+    ],
+  },
+};
+export let linearYScale: LinearScale = {
+  name: "yscale",
+  type: "linear",
+  range: "height",
+  zero: false,
+  domain: {
+    fields: [
+      {
+        data: "con",
+        field: "y",
+      },
+      {
+        data: "dis",
+        field: "y",
+      },
+    ],
+  },
+};
+
+export let logXScale: LogScale = {
+  name: "xscale",
+  type: "log",
+  range: "width",
+  zero: false,
+  base: 10,
+  nice: false,
+  clamp: true,
+  domain: {
+    fields: [
+      {
+        data: "con",
+        field: "x",
+      },
+      {
+        data: "dis",
+        field: "x",
+      },
+    ],
+  },
+};
+
+export let expYScale: PowScale = {
+  name: "yscale",
+  type: "pow",
+  exponent: 0.1,
+  range: "height",
+  zero: false,
+  nice: false,
+  domain: {
+    fields: [
+      {
+        data: "con",
+        field: "y",
+      },
+      {
+        data: "dis",
+        field: "y",
+      },
+    ],
+  },
+};
+
+export function buildVegaSpec(
+  specOptions: DistributionChartSpecOptions
+): VisualizationSpec {
+  let {
+    format = ".9~s",
+    color = "#739ECC",
+    title,
+    minX,
+    maxX,
+    logX,
+    expY,
+  } = specOptions;
+
+  let xScale = logX ? logXScale : linearXScale;
+  if (minX !== undefined && Number.isFinite(minX)) {
+    xScale = { ...xScale, domainMin: minX };
+  }
+
+  if (maxX !== undefined && Number.isFinite(maxX)) {
+    xScale = { ...xScale, domainMax: maxX };
+  }
+
+  let spec: VisualizationSpec = {
+    $schema: "https://vega.github.io/schema/vega/v5.json",
+    description: "A basic area chart example",
+    width: 500,
+    height: 100,
+    padding: 5,
+    data: [
+      {
+        name: "con",
+      },
+      {
+        name: "dis",
+      },
+    ],
+    signals: [],
+    scales: [xScale, expY ? expYScale : linearYScale],
+    axes: [
+      {
+        orient: "bottom",
+        scale: "xscale",
+        labelColor: "#727d93",
+        tickColor: "#fff",
+        tickOpacity: 0.0,
+        domainColor: "#fff",
+        domainOpacity: 0.0,
+        format: format,
+        tickCount: 10,
+      },
+    ],
+    marks: [
+      {
+        type: "area",
+        from: {
+          data: "con",
+        },
+        encode: {
+          update: {
+            interpolate: { value: "linear" },
+            x: {
+              scale: "xscale",
+              field: "x",
+            },
+            y: {
+              scale: "yscale",
+              field: "y",
+            },
+            y2: {
+              scale: "yscale",
+              value: 0,
+            },
+            fill: {
+              value: color,
+            },
+            fillOpacity: {
+              value: 1,
+            },
+          },
+        },
+      },
+      {
+        type: "rect",
+        from: {
+          data: "dis",
+        },
+        encode: {
+          enter: {
+            width: {
+              value: 1,
+            },
+          },
+          update: {
+            x: {
+              scale: "xscale",
+              field: "x",
+            },
+            y: {
+              scale: "yscale",
+              field: "y",
+            },
+            y2: {
+              scale: "yscale",
+              value: 0,
+            },
+            fill: {
+              value: "#2f65a7",
+            },
+          },
+        },
+      },
+      {
+        type: "symbol",
+        from: {
+          data: "dis",
+        },
+        encode: {
+          enter: {
+            shape: {
+              value: "circle",
+            },
+            size: [{ value: 100 }],
+            tooltip: {
+              signal: "datum.y",
+            },
+          },
+          update: {
+            x: {
+              scale: "xscale",
+              field: "x",
+            },
+            y: {
+              scale: "yscale",
+              field: "y",
+            },
+            fill: {
+              value: "#1e4577",
+            },
+          },
+        },
+      },
+    ],
+  };
+  if (title) {
+    spec = {
+      ...spec,
+      title: {
+        text: title,
+      },
+    };
+  }
+
+  return spec;
+}
diff --git a/packages/components/src/stories/SquiggleChart.stories.mdx b/packages/components/src/stories/SquiggleChart.stories.mdx
index 2483c985..2febfb6f 100644
--- a/packages/components/src/stories/SquiggleChart.stories.mdx
+++ b/packages/components/src/stories/SquiggleChart.stories.mdx
@@ -3,7 +3,7 @@ import { Canvas, Meta, Story, Props } from "@storybook/addon-docs";
 
 <Meta title="Squiggle/SquiggleChart" component={SquiggleChart} />
 
-export const Template = SquiggleChart;
+export const Template = (props) => <SquiggleChart {...props} />;
 /* 
   We have to hardcode a width here, because otherwise some interaction with
   Storybook creates an infinite loop with the internal width
diff --git a/packages/squiggle-lang/__tests__/Reducer/Reducer_Module/Reducer_Module_defineFFI_test.res b/packages/squiggle-lang/__tests__/Reducer/Reducer_Module/Reducer_Module_test.res
similarity index 83%
rename from packages/squiggle-lang/__tests__/Reducer/Reducer_Module/Reducer_Module_defineFFI_test.res
rename to packages/squiggle-lang/__tests__/Reducer/Reducer_Module/Reducer_Module_test.res
index a06c7a57..69fca252 100644
--- a/packages/squiggle-lang/__tests__/Reducer/Reducer_Module/Reducer_Module_defineFFI_test.res
+++ b/packages/squiggle-lang/__tests__/Reducer/Reducer_Module/Reducer_Module_test.res
@@ -22,6 +22,13 @@ module FooImplementation = {
   let makeFoo = (a: string, b: string, _environment): string => `I am ${a}-foo and I am ${b}-foo`
   let makeBar = (a: float, b: float, _environment): string =>
     `I am ${a->Js.Float.toString}-bar and I am ${b->Js.Float.toString}-bar`
+  // You can also define functions that has their internal errors
+  let makeReturningError = (_a: float, _b: float, _environment): result<float, ErrorValue.t> =>
+    if false {
+      0.->Ok
+    } else {
+      ErrorValue.RETodo("test error")->Error
+    }
 }
 
 // There is a potential for type modules to define lift functions
@@ -38,6 +45,17 @@ module FooFFI = {
     | [IEvNumber(a), IEvNumber(b)] => FooImplementation.makeBar(a, b, environment)->IEvString->Some
     | _ => None
     }
+  let makeReturningError: ExpressionT.optionFfiFnReturningResult = (
+    args: array<InternalExpressionValue.t>,
+    environment,
+  ) =>
+    switch args {
+    | [IEvNumber(a), IEvNumber(b)] =>
+      FooImplementation.makeReturningError(a, b, environment)
+      ->Belt.Result.map(v => v->InternalExpressionValue.IEvNumber)
+      ->Some
+    | _ => None
+    }
 }
 
 let fooModule: Module.t =
@@ -47,6 +65,7 @@ let fooModule: Module.t =
   ->Module.defineBool("fooBool", FooImplementation.fooBool)
   ->Module.defineFunction("makeFoo", FooFFI.makeFoo)
   ->Module.defineFunction("makeBar", FooFFI.makeBar)
+  ->Module.defineFunctionReturningResult("makeReturningError", FooFFI.makeReturningError)
 
 let makeBindings = (prevBindings: Bindings.t): Bindings.t =>
   prevBindings->Module.defineModule("Foo", fooModule)
diff --git a/packages/squiggle-lang/src/rescript/Reducer/Reducer_Expression/Reducer_Expression_T.res b/packages/squiggle-lang/src/rescript/Reducer/Reducer_Expression/Reducer_Expression_T.res
index dee70c88..bf4d0170 100644
--- a/packages/squiggle-lang/src/rescript/Reducer/Reducer_Expression/Reducer_Expression_T.res
+++ b/packages/squiggle-lang/src/rescript/Reducer/Reducer_Expression/Reducer_Expression_T.res
@@ -72,6 +72,10 @@ type ffiFn = (
 ) => result<internalExpressionValue, Reducer_ErrorValue.errorValue>
 
 type optionFfiFn = (array<internalExpressionValue>, environment) => option<internalExpressionValue>
+type optionFfiFnReturningResult = (
+  array<internalExpressionValue>,
+  environment,
+) => option<result<internalExpressionValue, Reducer_ErrorValue.errorValue>>
 
 type expressionOrFFI =
   | NotFFI(expression)
diff --git a/packages/squiggle-lang/src/rescript/Reducer/Reducer_Module/Reducer_Module.res b/packages/squiggle-lang/src/rescript/Reducer/Reducer_Module/Reducer_Module.res
index 62f9d8c7..34c304f9 100644
--- a/packages/squiggle-lang/src/rescript/Reducer/Reducer_Module/Reducer_Module.res
+++ b/packages/squiggle-lang/src/rescript/Reducer/Reducer_Module/Reducer_Module.res
@@ -126,6 +126,17 @@ let functionNotFoundErrorFFIFn = (functionName: string): ExpressionT.ffiFn => {
   }
 }
 
+let convertOptionToFfiFnReturningResult = (
+  myFunctionName: string,
+  myFunction: ExpressionT.optionFfiFnReturningResult,
+): ExpressionT.ffiFn => {
+  (args: array<InternalExpressionValue.t>, environment) => {
+    myFunction(args, environment)->Belt.Option.getWithDefault(
+      functionNotFoundErrorFFIFn(myFunctionName)(args, environment),
+    )
+  }
+}
+
 let convertOptionToFfiFn = (
   myFunctionName: string,
   myFunction: ExpressionT.optionFfiFn,
@@ -159,4 +170,15 @@ let defineFunction = (nameSpace: t, identifier: string, value: ExpressionT.optio
   nameSpace->define(identifier, convertOptionToFfiFn(identifier, value)->eLambdaFFIValue)
 }
 
-let emptyStdLib: t = emptyModule->defineBool("stdlib", true)
+let defineFunctionReturningResult = (
+  nameSpace: t,
+  identifier: string,
+  value: ExpressionT.optionFfiFnReturningResult,
+): t => {
+  nameSpace->define(
+    identifier,
+    convertOptionToFfiFnReturningResult(identifier, value)->eLambdaFFIValue,
+  )
+}
+
+let emptyStdLib: t = emptyModule->defineBool("_standardLibrary", true)