diff --git a/theatre/core/src/sheetObjects/SheetObject.ts b/theatre/core/src/sheetObjects/SheetObject.ts
index 4fc7689..fafa7ff 100644
--- a/theatre/core/src/sheetObjects/SheetObject.ts
+++ b/theatre/core/src/sheetObjects/SheetObject.ts
@@ -164,7 +164,7 @@ export default class SheetObject implements IdentityDerivationProvider {
               const leftDeserialized = deserializeAndSanitize(triple.left)
 
               const left =
-                typeof leftDeserialized === 'undefined'
+                leftDeserialized === undefined
                   ? propConfig.default
                   : leftDeserialized
 
@@ -173,7 +173,7 @@ export default class SheetObject implements IdentityDerivationProvider {
 
               const rightDeserialized = deserializeAndSanitize(triple.right)
               const right =
-                typeof rightDeserialized === 'undefined'
+                rightDeserialized === undefined
                   ? propConfig.default
                   : rightDeserialized
 
diff --git a/theatre/shared/src/propTypes/utils.ts b/theatre/shared/src/propTypes/utils.ts
index 3731b27..09e3382 100644
--- a/theatre/shared/src/propTypes/utils.ts
+++ b/theatre/shared/src/propTypes/utils.ts
@@ -20,7 +20,7 @@ export function getPropConfigByPath(
 ): undefined | PropTypeConfig {
   if (!parentConf) return undefined
   const [key, ...rest] = path
-  if (typeof key === 'undefined') return parentConf
+  if (key === undefined) return parentConf
   if (!isPropConfigComposite(parentConf)) return undefined
 
   const sub =
@@ -44,7 +44,7 @@ export function valueInProp<PropConfig extends PropTypeConfig_AllNonCompounds>(
   ? T
   : never {
   const sanitizedVal = propConfig.deserializeAndSanitize(value)
-  if (typeof sanitizedVal === 'undefined') {
+  if (sanitizedVal === undefined) {
     return propConfig.default
   } else {
     return sanitizedVal
diff --git a/theatre/shared/src/utils/deepMergeWithCache.ts b/theatre/shared/src/utils/deepMergeWithCache.ts
index a2f4197..96f2b31 100644
--- a/theatre/shared/src/utils/deepMergeWithCache.ts
+++ b/theatre/shared/src/utils/deepMergeWithCache.ts
@@ -24,7 +24,7 @@ export default function deepMergeWithCache<T extends SerializableMap>(
     merged[key] =
       typeof valueInOverride === 'object' && typeof valueInBase === 'object'
         ? deepMergeWithCache(valueInBase, valueInOverride, cache)
-        : typeof valueInOverride === 'undefined'
+        : valueInOverride === undefined
         ? valueInBase
         : valueInOverride
   }
diff --git a/theatre/shared/src/utils/forEachDeep.ts b/theatre/shared/src/utils/forEachDeep.ts
index 8d3ea2b..be188d1 100644
--- a/theatre/shared/src/utils/forEachDeep.ts
+++ b/theatre/shared/src/utils/forEachDeep.ts
@@ -12,7 +12,7 @@ export default function forEachDeep<
     for (const [key, value] of Object.entries(m)) {
       forEachDeep(value!, fn, [...startingPath, key])
     }
-  } else if (typeof m === 'undefined' || m === null) {
+  } else if (m === undefined || m === null) {
     return
   } else {
     fn(m as $IntentionalAny as Primitive, startingPath)
diff --git a/theatre/studio/src/StudioStore/createTransactionPrivateApi.ts b/theatre/studio/src/StudioStore/createTransactionPrivateApi.ts
index 8fd5303..1f4ecd5 100644
--- a/theatre/studio/src/StudioStore/createTransactionPrivateApi.ts
+++ b/theatre/studio/src/StudioStore/createTransactionPrivateApi.ts
@@ -100,14 +100,14 @@ export default function createTransactionPrivateApi(
           propConfig: PropTypeConfig_AllNonCompounds,
           path: PathToProp,
         ) => {
-          if (typeof value === 'undefined' || value === null) {
+          if (value === undefined || value === null) {
             return
           }
 
           const deserialized = cloneDeepSerializable(
             propConfig.deserializeAndSanitize(value),
           )
-          if (typeof deserialized === 'undefined') {
+          if (deserialized === undefined) {
             throw new Error(
               `Invalid value ${userReadableTypeOfValue(
                 value,
diff --git a/theatre/studio/src/store/stateEditors.ts b/theatre/studio/src/store/stateEditors.ts
index ce555ed..d401009 100644
--- a/theatre/studio/src/store/stateEditors.ts
+++ b/theatre/studio/src/store/stateEditors.ts
@@ -58,7 +58,7 @@ export const setDrafts__onlyMeantToBeCalledByTransaction = (
 let currentDrafts: undefined | Drafts
 
 const drafts = (): Drafts => {
-  if (typeof currentDrafts === 'undefined') {
+  if (currentDrafts === undefined) {
     throw new Error(
       `Calling stateEditors outside of a transaction is not allowed.`,
     )