diff --git a/test/about-us.test.ts b/test/about-us.test.ts
index 2d2c03b62..915de2dab 100644
--- a/test/about-us.test.ts
+++ b/test/about-us.test.ts
@@ -9,7 +9,7 @@ import * as fc from './fc.js'
 import { shouldNotBeCalled } from './should-not-be-called.js'
 
 describe('aboutUs', () => {
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 })])('when the page can be loaded', async key => {
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 })])('when the page can be loaded', async key => {
     const fetch = fetchMock.sandbox().getOnce(
       {
         url: 'https://content.prereview.org/ghost/api/content/pages/6154aa157741400e8722bb14',
@@ -32,7 +32,7 @@ describe('aboutUs', () => {
     })
   })
 
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.fetchResponse()])(
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 }), fc.fetchResponse()])(
     'when the page cannot be loaded',
     async (key, response) => {
       const fetch = fetchMock.sandbox().getOnce(
diff --git a/test/cloudinary.test.ts b/test/cloudinary.test.ts
index 03307cc95..fddadb567 100644
--- a/test/cloudinary.test.ts
+++ b/test/cloudinary.test.ts
@@ -15,8 +15,8 @@ describe('getAvatarFromCloudinary', () => {
   test.prop([
     fc.record({
       cloudName: fc.lorem({ maxCount: 1 }),
-      key: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-      secret: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+      key: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+      secret: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
     }),
     fc.orcid(),
     fc.nonEmptyStringOf(fc.alphanumeric()),
@@ -41,8 +41,8 @@ describe('getAvatarFromCloudinary', () => {
   test.prop([
     fc.record({
       cloudName: fc.lorem({ maxCount: 1 }),
-      key: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-      secret: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+      key: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+      secret: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
     }),
     fc.orcid(),
   ])("when the ORCID iD doesn't have an avatar", async (cloudinaryApi, orcid) => {
@@ -57,8 +57,8 @@ describe('getAvatarFromCloudinary', () => {
   test.prop([
     fc.record({
       cloudName: fc.lorem({ maxCount: 1 }),
-      key: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-      secret: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+      key: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+      secret: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
     }),
     fc.orcid(),
   ])('when the avatar is unavailable', async (cloudinaryApi, orcid) => {
@@ -77,8 +77,8 @@ describe('saveAvatarOnCloudinary', () => {
       fc.date(),
       fc.record({
         cloudName: fc.lorem({ maxCount: 1 }),
-        key: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-        secret: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+        key: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+        secret: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
       }),
       fc.origin(),
       fc.orcid(),
@@ -134,8 +134,8 @@ describe('saveAvatarOnCloudinary', () => {
       fc.date(),
       fc.record({
         cloudName: fc.lorem({ maxCount: 1 }),
-        key: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-        secret: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+        key: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+        secret: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
       }),
       fc.origin(),
       fc.orcid(),
@@ -212,8 +212,8 @@ describe('saveAvatarOnCloudinary', () => {
       fc.date(),
       fc.record({
         cloudName: fc.lorem({ maxCount: 1 }),
-        key: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-        secret: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+        key: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+        secret: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
       }),
       fc.origin(),
       fc.orcid(),
@@ -266,8 +266,8 @@ describe('saveAvatarOnCloudinary', () => {
     fc.date(),
     fc.record({
       cloudName: fc.lorem({ maxCount: 1 }),
-      key: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-      secret: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+      key: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+      secret: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
     }),
     fc.origin(),
     fc.orcid(),
@@ -312,8 +312,8 @@ describe('saveAvatarOnCloudinary', () => {
     fc.date(),
     fc.record({
       cloudName: fc.lorem({ maxCount: 1 }),
-      key: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-      secret: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+      key: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+      secret: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
     }),
     fc.origin(),
     fc.orcid(),
@@ -354,8 +354,8 @@ describe('removeAvatarFromCloudinary', () => {
     fc.date(),
     fc.record({
       cloudName: fc.lorem({ maxCount: 1 }),
-      key: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-      secret: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+      key: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+      secret: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
     }),
     fc.orcid(),
     fc.nonEmptyString(),
@@ -401,8 +401,8 @@ describe('removeAvatarFromCloudinary', () => {
     fc.date(),
     fc.record({
       cloudName: fc.lorem({ maxCount: 1 }),
-      key: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-      secret: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+      key: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+      secret: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
     }),
     fc.orcid(),
     fc.nonEmptyString(),
@@ -435,8 +435,8 @@ describe('removeAvatarFromCloudinary', () => {
     fc.date(),
     fc.record({
       cloudName: fc.lorem({ maxCount: 1 }),
-      key: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-      secret: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+      key: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+      secret: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
     }),
     fc.orcid(),
     fc.nonEmptyString(),
@@ -462,8 +462,8 @@ describe('removeAvatarFromCloudinary', () => {
     fc.date(),
     fc.record({
       cloudName: fc.lorem({ maxCount: 1 }),
-      key: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-      secret: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+      key: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+      secret: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
     }),
     fc.orcid(),
   ])('when the avatar cannot be loaded locally', async (date, cloudinaryApi, orcid) => {
@@ -486,8 +486,8 @@ describe('removeAvatarFromCloudinary', () => {
     fc.date(),
     fc.record({
       cloudName: fc.lorem({ maxCount: 1 }),
-      key: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-      secret: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+      key: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+      secret: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
     }),
     fc.orcid(),
   ])('when there is no avatar', async (date, cloudinaryApi, orcid) => {
diff --git a/test/clubs.test.ts b/test/clubs.test.ts
index 45f97cfdf..ed738e52b 100644
--- a/test/clubs.test.ts
+++ b/test/clubs.test.ts
@@ -9,7 +9,7 @@ import * as fc from './fc.js'
 import { shouldNotBeCalled } from './should-not-be-called.js'
 
 describe('clubs', () => {
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 })])('when the page can be loaded', async key => {
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 })])('when the page can be loaded', async key => {
     const fetch = fetchMock.sandbox().getOnce(
       {
         url: 'https://content.prereview.org/ghost/api/content/pages/64637b4c07fb34a92c7f84ec',
@@ -32,7 +32,7 @@ describe('clubs', () => {
     })
   })
 
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.fetchResponse()])(
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 }), fc.fetchResponse()])(
     'when the page cannot be loaded',
     async (key, response) => {
       const fetch = fetchMock.sandbox().getOnce(
diff --git a/test/code-of-conduct.test.ts b/test/code-of-conduct.test.ts
index 469433631..373bdcf5a 100644
--- a/test/code-of-conduct.test.ts
+++ b/test/code-of-conduct.test.ts
@@ -9,7 +9,7 @@ import * as fc from './fc.js'
 import { shouldNotBeCalled } from './should-not-be-called.js'
 
 describe('codeOfConduct', () => {
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 })])('when the page can be loaded', async key => {
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 })])('when the page can be loaded', async key => {
     const fetch = fetchMock.sandbox().getOnce(
       {
         url: 'https://content.prereview.org/ghost/api/content/pages/6154aa157741400e8722bb00',
@@ -32,7 +32,7 @@ describe('codeOfConduct', () => {
     })
   })
 
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.fetchResponse()])(
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 }), fc.fetchResponse()])(
     'when the page cannot be loaded',
     async (key, response) => {
       const fetch = fetchMock.sandbox().getOnce(
diff --git a/test/edia-statement.test.ts b/test/edia-statement.test.ts
index 49b903c69..219fa0683 100644
--- a/test/edia-statement.test.ts
+++ b/test/edia-statement.test.ts
@@ -9,7 +9,7 @@ import * as fc from './fc.js'
 import { shouldNotBeCalled } from './should-not-be-called.js'
 
 describe('ediaStatement', () => {
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 })])('when the page can be loaded', async key => {
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 })])('when the page can be loaded', async key => {
     const fetch = fetchMock.sandbox().getOnce(
       {
         url: 'https://content.prereview.org/ghost/api/content/pages/6154aa157741400e8722bb17',
@@ -32,7 +32,7 @@ describe('ediaStatement', () => {
     })
   })
 
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.fetchResponse()])(
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 }), fc.fetchResponse()])(
     'when the page cannot be loaded',
     async (key, response) => {
       const fetch = fetchMock.sandbox().getOnce(
diff --git a/test/fc.ts b/test/fc.ts
index 2c18d7d80..3ef2faa9a 100644
--- a/test/fc.ts
+++ b/test/fc.ts
@@ -140,7 +140,6 @@ export const {
   option,
   record,
   string,
-  stringOf,
   tuple,
   uniqueArray,
   webUrl,
@@ -423,14 +422,14 @@ export const oauth = (): fc.Arbitrary<Omit<OrcidOAuthEnv['orcidOauth'] & OAuthEn
 export const doiRegistrant = (): fc.Arbitrary<string> =>
   fc
     .tuple(
-      fc.stringOf(constantFrom('0', '1', '2', '3', '4', '5', '6', '7', '8', '9'), { minLength: 2 }),
-      fc.array(fc.stringOf(constantFrom('0', '1', '2', '3', '4', '5', '6', '7', '8', '9'), { minLength: 1 })),
+      fc.string({ unit: constantFrom('0', '1', '2', '3', '4', '5', '6', '7', '8', '9'), minLength: 2 }),
+      fc.array(fc.string({ unit: constantFrom('0', '1', '2', '3', '4', '5', '6', '7', '8', '9'), minLength: 1 })),
     )
     .map(([one, two]) => [one, ...two].join('.'))
 
 export const doi = <R extends string>(withRegistrant?: fc.Arbitrary<R>): fc.Arbitrary<Doi<R>> =>
   fc
-    .tuple(withRegistrant ?? doiRegistrant(), fc.unicodeString({ minLength: 1 }))
+    .tuple(withRegistrant ?? doiRegistrant(), fc.string({ unit: 'grapheme', minLength: 1 }))
     .map(([prefix, suffix]) => `10.${prefix}/${suffix}`)
     .filter(isDoi as Refinement<unknown, Doi<R>>)
 
@@ -486,8 +485,8 @@ export const africarxivFigsharePreprintId = (): fc.Arbitrary<AfricarxivFigshareP
 export const africarxivFigsharePreprintUrl = (): fc.Arbitrary<[URL, AfricarxivFigsharePreprintId]> =>
   fc
     .tuple(
-      fc.stringOf(fc.oneof(alphanumeric(), constant('-')), { minLength: 1 }),
-      fc.stringOf(fc.oneof(alphanumeric(), constantFrom('_')), { minLength: 1 }),
+      fc.string({ unit: fc.oneof(alphanumeric(), constant('-')), minLength: 1 }),
+      fc.string({ unit: fc.oneof(alphanumeric(), constantFrom('_')), minLength: 1 }),
       fc.integer({ min: 1 }),
     )
     .map(([type, title, id]) => [
@@ -503,7 +502,7 @@ export const africarxivOsfPreprintId = (): fc.Arbitrary<AfricarxivOsfPreprintId>
 
 export const africarxivOsfPreprintUrl = (): fc.Arbitrary<[URL, AfricarxivOsfPreprintId]> =>
   fc
-    .stringOf(alphanumeric(), { minLength: 1 })
+    .string({ unit: alphanumeric(), minLength: 1 })
     .map(id => [
       new URL(`https://osf.io/preprints/africarxiv/${id}`),
       { type: 'africarxiv', value: `10.31730/osf.io/${id}` as Doi<'31730'> },
@@ -529,7 +528,7 @@ export const arxivPreprintId = (): fc.Arbitrary<ArxivPreprintId> =>
 
 export const arxivPreprintUrl = (): fc.Arbitrary<[URL, ArxivPreprintId]> =>
   fc
-    .stringOf(constantFrom('0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '.'), { minLength: 1 })
+    .string({ unit: constantFrom('0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '.'), minLength: 1 })
     .filter(suffix => isDoi(`10.48550/${suffix}`))
     .map(suffix => [
       new URL(`https://arxiv.org/abs/${suffix}`),
@@ -553,7 +552,7 @@ export const biorxivPreprintId = (): fc.Arbitrary<BiorxivPreprintId> =>
 
 export const biorxivPreprintUrl = (): fc.Arbitrary<[URL, BiorxivPreprintId]> =>
   fc
-    .stringOf(constantFrom('0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '.'), { minLength: 1 })
+    .string({ unit: constantFrom('0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '.'), minLength: 1 })
     .filter(suffix => isDoi(`10.1101/${suffix}`))
     .map(suffix => [
       new URL(`https://www.biorxiv.org/content/10.1101/${suffix}`),
@@ -568,7 +567,7 @@ export const chemrxivPreprintId = (): fc.Arbitrary<ChemrxivPreprintId> =>
 
 export const chemrxivPreprintUrl = (): fc.Arbitrary<URL> =>
   fc
-    .stringOf(alphanumeric(), { minLength: 1 })
+    .string({ unit: alphanumeric(), minLength: 1 })
     .map(id => new URL(`https://chemrxiv.org/engage/chemrxiv/article-details/${id}`))
 
 export const curvenotePreprintId = (): fc.Arbitrary<CurvenotePreprintId> =>
@@ -603,7 +602,7 @@ export const edarxivPreprintId = (): fc.Arbitrary<EdarxivPreprintId> =>
 
 export const edarxivPreprintUrl = (): fc.Arbitrary<[URL, EdarxivPreprintId]> =>
   fc
-    .stringOf(alphanumeric(), { minLength: 1 })
+    .string({ unit: alphanumeric(), minLength: 1 })
     .map(id => [
       new URL(`https://edarxiv.org/${id}`),
       { type: 'edarxiv', value: `10.35542/osf.io/${id}` as Doi<'35542'> },
@@ -631,7 +630,7 @@ export const medrxivPreprintId = (): fc.Arbitrary<MedrxivPreprintId> =>
 
 export const medrxivPreprintUrl = (): fc.Arbitrary<[URL, MedrxivPreprintId]> =>
   fc
-    .stringOf(constantFrom('0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '.'), { minLength: 1 })
+    .string({ unit: constantFrom('0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '.'), minLength: 1 })
     .filter(suffix => isDoi(`10.1101/${suffix}`))
     .map(suffix => [
       new URL(`https://www.medrxiv.org/content/10.1101/${suffix}`),
@@ -646,7 +645,7 @@ export const metaarxivPreprintId = (): fc.Arbitrary<MetaarxivPreprintId> =>
 
 export const metaarxivPreprintUrl = (): fc.Arbitrary<[URL, MetaarxivPreprintId]> =>
   fc
-    .stringOf(alphanumeric(), { minLength: 1 })
+    .string({ unit: alphanumeric(), minLength: 1 })
     .map(id => [
       new URL(`https://osf.io/preprints/metaarxiv/${id}`),
       { type: 'metaarxiv', value: `10.31222/osf.io/${id}` as Doi<'31222'> },
@@ -666,7 +665,7 @@ export const osfPreprintsPreprintId = (): fc.Arbitrary<OsfPreprintsPreprintId> =
 
 export const osfPreprintsPreprintUrl = (): fc.Arbitrary<[URL, OsfPreprintsPreprintId]> =>
   fc
-    .stringOf(alphanumeric(), { minLength: 1 })
+    .string({ unit: alphanumeric(), minLength: 1 })
     .map(id => [
       new URL(`https://osf.io/${id}`),
       { type: 'osf-preprints', value: `10.31219/osf.io/${id}` as Doi<'31219'> },
@@ -690,7 +689,7 @@ export const preprintsorgPreprintId = (): fc.Arbitrary<PreprintsorgPreprintId> =
 export const preprintsorgPreprintUrl = (): fc.Arbitrary<[URL, PreprintsorgPreprintId]> =>
   fc
     .tuple(
-      fc.stringOf(fc.oneof(alphanumeric(), constant('.')), { minLength: 1 }).filter(id => !/^\.{1,2}$/.test(id)),
+      fc.string({ unit: fc.oneof(alphanumeric(), constant('.')), minLength: 1 }).filter(id => !/^\.{1,2}$/.test(id)),
       fc.integer({ min: 1 }),
     )
     .map(([id, version]) => [
@@ -706,7 +705,7 @@ export const psyarxivPreprintId = (): fc.Arbitrary<PsyarxivPreprintId> =>
 
 export const psyarxivPreprintUrl = (): fc.Arbitrary<[URL, PsyarxivPreprintId]> =>
   fc
-    .stringOf(alphanumeric(), { minLength: 1 })
+    .string({ unit: alphanumeric(), minLength: 1 })
     .map(id => [
       new URL(`https://psyarxiv.com/${id}`),
       { type: 'psyarxiv', value: `10.31234/osf.io/${id}` as Doi<'31234'> },
@@ -766,7 +765,7 @@ export const socarxivPreprintId = (): fc.Arbitrary<SocarxivPreprintId> =>
 
 export const socarxivPreprintUrl = (): fc.Arbitrary<[URL, SocarxivPreprintId]> =>
   fc
-    .stringOf(alphanumeric(), { minLength: 1 })
+    .string({ unit: alphanumeric(), minLength: 1 })
     .map(id => [
       new URL(`https://osf.io/preprints/socarxiv/${id}`),
       { type: 'socarxiv', value: `10.31235/osf.io/${id}` as Doi<'31235'> },
@@ -879,7 +878,8 @@ export const datacitePreprintId = (): fc.Arbitrary<DatacitePreprintId> =>
 
 export const orcid = (): fc.Arbitrary<Orcid> =>
   fc
-    .stringOf(constantFrom('0', '1', '2', '3', '4', '5', '6', '7', '8', '9'), {
+    .string({
+      unit: constantFrom('0', '1', '2', '3', '4', '5', '6', '7', '8', '9'),
       minLength: 4 + 4 + 4 + 3,
       maxLength: 4 + 4 + 4 + 3,
     })
@@ -1062,10 +1062,10 @@ export const requestMethod = (): fc.Arbitrary<RequestMethod> =>
   constantFrom('CONNECT', 'DELETE', 'GET', 'HEAD', 'OPTIONS', 'PATCH', 'POST', 'PUT', 'TRACE')
 
 const headerName = () =>
-  fc.stringOf(
-    fc.char().filter(char => /^[\^_`a-zA-Z\-0-9!#$%&'*+.|~]$/.test(char)),
-    { minLength: 1 },
-  )
+  fc.string({
+    unit: fc.string({ minLength: 1, maxLength: 1 }).filter(char => /^[\^_`a-zA-Z\-0-9!#$%&'*+.|~]$/.test(char)),
+    minLength: 1,
+  })
 
 export const headers = (include: fc.Arbitrary<Record<string, string>> = constant({})) =>
   fc
@@ -1160,7 +1160,7 @@ export const nonEmptyArray = <T>(
 export const nonEmptyString = (): fc.Arbitrary<NonEmptyString> => fc.string({ minLength: 1 }).filter(isNonEmptyString)
 
 export const nonEmptyStringOf = (charArb: fc.Arbitrary<string>): fc.Arbitrary<NonEmptyString> =>
-  fc.stringOf(charArb, { minLength: 1 }).filter(isNonEmptyString)
+  fc.string({ unit: charArb, minLength: 1 }).filter(isNonEmptyString)
 
 export const languageCode = (): fc.Arbitrary<LanguageCode> => constantFrom(...ISO6391.getAllCodes())
 
diff --git a/test/funding.test.ts b/test/funding.test.ts
index 767b61b88..e8c8ca4fc 100644
--- a/test/funding.test.ts
+++ b/test/funding.test.ts
@@ -9,7 +9,7 @@ import * as fc from './fc.js'
 import { shouldNotBeCalled } from './should-not-be-called.js'
 
 describe('funding', () => {
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 })])('when the page can be loaded', async key => {
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 })])('when the page can be loaded', async key => {
     const fetch = fetchMock.sandbox().getOnce(
       {
         url: 'https://content.prereview.org/ghost/api/content/pages/6154aa157741400e8722bb12',
@@ -32,7 +32,7 @@ describe('funding', () => {
     })
   })
 
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.fetchResponse()])(
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 }), fc.fetchResponse()])(
     'when the page cannot be loaded',
     async (key, response) => {
       const fetch = fetchMock.sandbox().getOnce(
diff --git a/test/ghost.test.ts b/test/ghost.test.ts
index a1e352af0..f399b9abb 100644
--- a/test/ghost.test.ts
+++ b/test/ghost.test.ts
@@ -10,8 +10,8 @@ import { shouldNotBeCalled } from './should-not-be-called.js'
 
 describe('getPage', () => {
   test.prop([
-    fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-    fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
     fc.sanitisedHtml(),
   ])('when the page can be decoded', async (id, key, html) => {
     const actual = await _.getPage(id)({
@@ -28,95 +28,93 @@ describe('getPage', () => {
     expect(actual).toStrictEqual(E.right(html))
   })
 
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.stringOf(fc.alphanumeric(), { minLength: 1 })])(
-    'when the page contains links',
-    async (id, key) => {
-      const actual = await _.getPage(id)({
-        fetch: fetchMock.sandbox().getOnce(
-          { url: `https://content.prereview.org/ghost/api/content/pages/${id}`, query: { key } },
-          {
-            body: {
-              pages: [
-                {
-                  html: '<a href="https://airtable.com/appNMgC4snjFIJQ0X/shrV1HBbujo5ZZbzN">Start a Club!</a><a href="https://prereview.org/clubs/asapbio-cancer-biology" rel="noopener noreferrer">ASAPbio Cancer Biology Crowd</a><a href="https://prereview.org/clubs/asapbio-metabolism" rel="noopener noreferrer">ASAPbio Metabolism Crowd</a><a href="http://prereview.org">PREreview</a>',
-                },
-              ],
-            },
+  test.prop([
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+  ])('when the page contains links', async (id, key) => {
+    const actual = await _.getPage(id)({
+      fetch: fetchMock.sandbox().getOnce(
+        { url: `https://content.prereview.org/ghost/api/content/pages/${id}`, query: { key } },
+        {
+          body: {
+            pages: [
+              {
+                html: '<a href="https://airtable.com/appNMgC4snjFIJQ0X/shrV1HBbujo5ZZbzN">Start a Club!</a><a href="https://prereview.org/clubs/asapbio-cancer-biology" rel="noopener noreferrer">ASAPbio Cancer Biology Crowd</a><a href="https://prereview.org/clubs/asapbio-metabolism" rel="noopener noreferrer">ASAPbio Metabolism Crowd</a><a href="http://prereview.org">PREreview</a>',
+              },
+            ],
           },
+        },
+      ),
+      ghostApi: { key },
+      sleep: shouldNotBeCalled,
+    })()
+
+    expect(actual).toStrictEqual(
+      E.right(
+        rawHtml(
+          '<a href="https://airtable.com/appNMgC4snjFIJQ0X/shrV1HBbujo5ZZbzN">Start a Club!</a><a href="/clubs/asapbio-cancer-biology">ASAPbio Cancer Biology Crowd</a><a href="/clubs/asapbio-metabolism">ASAPbio Metabolism Crowd</a><a href="/">PREreview</a>',
         ),
-        ghostApi: { key },
-        sleep: shouldNotBeCalled,
-      })()
-
-      expect(actual).toStrictEqual(
-        E.right(
-          rawHtml(
-            '<a href="https://airtable.com/appNMgC4snjFIJQ0X/shrV1HBbujo5ZZbzN">Start a Club!</a><a href="/clubs/asapbio-cancer-biology">ASAPbio Cancer Biology Crowd</a><a href="/clubs/asapbio-metabolism">ASAPbio Metabolism Crowd</a><a href="/">PREreview</a>',
-          ),
-        ),
-      )
-    },
-  )
-
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.stringOf(fc.alphanumeric(), { minLength: 1 })])(
-    'when the page contains an image',
-    async (id, key) => {
-      const actual = await _.getPage(id)({
-        fetch: fetchMock.sandbox().getOnce(
-          { url: `https://content.prereview.org/ghost/api/content/pages/${id}`, query: { key } },
-          {
-            body: {
-              pages: [
-                {
-                  html: '<figure class="kg-card kg-image-card"><img src="https://content.prereview.org/content/images/2021/09/Screen-Shot-2021-09-30-at-11.52.02-AM.png" class="kg-image" alt loading="lazy" width="1464" height="192" srcset="https://content.prereview.org/content/images/size/w600/2021/09/Screen-Shot-2021-09-30-at-11.52.02-AM.png 600w, https://content.prereview.org/content/images/size/w1000/2021/09/Screen-Shot-2021-09-30-at-11.52.02-AM.png 1000w, https://content.prereview.org/content/images/2021/09/Screen-Shot-2021-09-30-at-11.52.02-AM.png 1464w" sizes="(min-width: 720px) 720px"></figure>',
-                },
-              ],
-            },
+      ),
+    )
+  })
+
+  test.prop([
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+  ])('when the page contains an image', async (id, key) => {
+    const actual = await _.getPage(id)({
+      fetch: fetchMock.sandbox().getOnce(
+        { url: `https://content.prereview.org/ghost/api/content/pages/${id}`, query: { key } },
+        {
+          body: {
+            pages: [
+              {
+                html: '<figure class="kg-card kg-image-card"><img src="https://content.prereview.org/content/images/2021/09/Screen-Shot-2021-09-30-at-11.52.02-AM.png" class="kg-image" alt loading="lazy" width="1464" height="192" srcset="https://content.prereview.org/content/images/size/w600/2021/09/Screen-Shot-2021-09-30-at-11.52.02-AM.png 600w, https://content.prereview.org/content/images/size/w1000/2021/09/Screen-Shot-2021-09-30-at-11.52.02-AM.png 1000w, https://content.prereview.org/content/images/2021/09/Screen-Shot-2021-09-30-at-11.52.02-AM.png 1464w" sizes="(min-width: 720px) 720px"></figure>',
+              },
+            ],
           },
+        },
+      ),
+      ghostApi: { key },
+      sleep: shouldNotBeCalled,
+    })()
+
+    expect(actual).toStrictEqual(
+      E.right(
+        rawHtml(
+          '<img src="https://content.prereview.org/content/images/2021/09/Screen-Shot-2021-09-30-at-11.52.02-AM.png" alt="" width="1464" height="192" />',
         ),
-        ghostApi: { key },
-        sleep: shouldNotBeCalled,
-      })()
-
-      expect(actual).toStrictEqual(
-        E.right(
-          rawHtml(
-            '<img src="https://content.prereview.org/content/images/2021/09/Screen-Shot-2021-09-30-at-11.52.02-AM.png" alt="" width="1464" height="192" />',
-          ),
-        ),
-      )
-    },
-  )
-
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.stringOf(fc.alphanumeric(), { minLength: 1 })])(
-    'when the page contains a button',
-    async (id, key) => {
-      const actual = await _.getPage(id)({
-        fetch: fetchMock.sandbox().getOnce(
-          { url: `https://content.prereview.org/ghost/api/content/pages/${id}`, query: { key } },
-          {
-            body: {
-              pages: [
-                {
-                  html: '<div class="kg-card kg-button-card kg-align-center"><a href="https://donorbox.org/prereview" class="kg-btn kg-btn-accent">Donate</a></div>',
-                },
-              ],
-            },
+      ),
+    )
+  })
+
+  test.prop([
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+  ])('when the page contains a button', async (id, key) => {
+    const actual = await _.getPage(id)({
+      fetch: fetchMock.sandbox().getOnce(
+        { url: `https://content.prereview.org/ghost/api/content/pages/${id}`, query: { key } },
+        {
+          body: {
+            pages: [
+              {
+                html: '<div class="kg-card kg-button-card kg-align-center"><a href="https://donorbox.org/prereview" class="kg-btn kg-btn-accent">Donate</a></div>',
+              },
+            ],
           },
-        ),
-        ghostApi: { key },
-        sleep: shouldNotBeCalled,
-      })()
+        },
+      ),
+      ghostApi: { key },
+      sleep: shouldNotBeCalled,
+    })()
 
-      expect(actual).toStrictEqual(
-        E.right(rawHtml('<a href="https://donorbox.org/prereview" class="button">Donate</a>')),
-      )
-    },
-  )
+    expect(actual).toStrictEqual(E.right(rawHtml('<a href="https://donorbox.org/prereview" class="button">Donate</a>')))
+  })
 
   test.prop([
-    fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-    fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
     fc.sanitisedHtml(),
   ])("revalidates the page if it's stale", async (id, key, html) => {
     const fetch = fetchMock
@@ -145,8 +143,8 @@ describe('getPage', () => {
   })
 
   test.prop([
-    fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-    fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
     fc.fetchResponse({ status: fc.constant(Status.OK) }),
   ])('when the response cannot be decoded', async (id, key, response) => {
     const fetch = fetchMock
@@ -163,29 +161,26 @@ describe('getPage', () => {
     expect(fetch.done()).toBeTruthy()
   })
 
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.stringOf(fc.alphanumeric(), { minLength: 1 })])(
-    'when the response has a 404 status code',
-    async (id, key) => {
-      const fetch = fetchMock
-        .sandbox()
-        .getOnce(
-          { url: `https://content.prereview.org/ghost/api/content/pages/${id}`, query: { key } },
-          Status.NotFound,
-        )
+  test.prop([
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+  ])('when the response has a 404 status code', async (id, key) => {
+    const fetch = fetchMock
+      .sandbox()
+      .getOnce({ url: `https://content.prereview.org/ghost/api/content/pages/${id}`, query: { key } }, Status.NotFound)
 
-      const actual = await _.getPage(id)({
-        fetch,
-        ghostApi: { key },
-        sleep: shouldNotBeCalled,
-      })()
+    const actual = await _.getPage(id)({
+      fetch,
+      ghostApi: { key },
+      sleep: shouldNotBeCalled,
+    })()
 
-      expect(actual).toStrictEqual(E.left('not-found'))
-    },
-  )
+    expect(actual).toStrictEqual(E.left('not-found'))
+  })
 
   test.prop([
-    fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-    fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
     fc.integer({ min: 200, max: 599 }).filter(status => status !== Status.OK && status !== Status.NotFound),
   ])('when the response has a non-200/404 status code', async (id, key, status) => {
     const fetch = fetchMock
@@ -203,8 +198,8 @@ describe('getPage', () => {
   })
 
   test.prop([
-    fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-    fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
     fc.error(),
   ])('when fetch throws an error', async (id, key, error) => {
     const actual = await _.getPage(id)({
diff --git a/test/how-to-use.test.ts b/test/how-to-use.test.ts
index 2afe6a8c4..9e6a69a0e 100644
--- a/test/how-to-use.test.ts
+++ b/test/how-to-use.test.ts
@@ -9,7 +9,7 @@ import * as fc from './fc.js'
 import { shouldNotBeCalled } from './should-not-be-called.js'
 
 describe('howToUse', () => {
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 })])('when the page can be loaded', async key => {
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 })])('when the page can be loaded', async key => {
     const fetch = fetchMock.sandbox().getOnce(
       {
         url: 'https://content.prereview.org/ghost/api/content/pages/651d895e07fb34a92c7f8d28',
@@ -32,7 +32,7 @@ describe('howToUse', () => {
     })
   })
 
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.fetchResponse()])(
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 }), fc.fetchResponse()])(
     'when the page cannot be loaded',
     async (key, response) => {
       const fetch = fetchMock.sandbox().getOnce(
diff --git a/test/live-reviews.test.ts b/test/live-reviews.test.ts
index 991210c71..d64191123 100644
--- a/test/live-reviews.test.ts
+++ b/test/live-reviews.test.ts
@@ -9,7 +9,7 @@ import * as fc from './fc.js'
 import { shouldNotBeCalled } from './should-not-be-called.js'
 
 describe('liveReviews', () => {
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 })])('when the page can be loaded', async key => {
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 })])('when the page can be loaded', async key => {
     const fetch = fetchMock.sandbox().getOnce(
       {
         url: 'https://content.prereview.org/ghost/api/content/pages/6154aa157741400e8722bb10',
@@ -32,7 +32,7 @@ describe('liveReviews', () => {
     })
   })
 
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.fetchResponse()])(
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 }), fc.fetchResponse()])(
     'when the page cannot be loaded',
     async (key, response) => {
       const fetch = fetchMock.sandbox().getOnce(
diff --git a/test/mailjet.test.ts b/test/mailjet.test.ts
index 29c9e95f3..8165a238a 100644
--- a/test/mailjet.test.ts
+++ b/test/mailjet.test.ts
@@ -10,8 +10,8 @@ import * as fc from './fc.js'
 describe('sendEmailWithMailjet', () => {
   test.prop([
     fc.record({
-      key: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-      secret: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+      key: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+      secret: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
       sandbox: fc.boolean(),
     }),
     fc.email(),
@@ -52,8 +52,8 @@ describe('sendEmailWithMailjet', () => {
 
   test.prop([
     fc.record({
-      key: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-      secret: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+      key: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+      secret: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
       sandbox: fc.boolean(),
     }),
     fc.email(),
@@ -80,8 +80,8 @@ describe('sendEmailWithMailjet', () => {
 
   test.prop([
     fc.record({
-      key: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-      secret: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+      key: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+      secret: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
       sandbox: fc.boolean(),
     }),
     fc.email(),
@@ -109,8 +109,8 @@ describe('sendEmailWithMailjet', () => {
 
   test.prop([
     fc.record({
-      key: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
-      secret: fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+      key: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
+      secret: fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
       sandbox: fc.boolean(),
     }),
     fc.email(),
diff --git a/test/people.test.ts b/test/people.test.ts
index 600013414..f079841fb 100644
--- a/test/people.test.ts
+++ b/test/people.test.ts
@@ -9,7 +9,7 @@ import * as fc from './fc.js'
 import { shouldNotBeCalled } from './should-not-be-called.js'
 
 describe('people', () => {
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 })])('when the page can be loaded', async key => {
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 })])('when the page can be loaded', async key => {
     const fetch = fetchMock.sandbox().getOnce(
       {
         url: 'https://content.prereview.org/ghost/api/content/pages/6154aa157741400e8722bb0a',
@@ -32,7 +32,7 @@ describe('people', () => {
     })
   })
 
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.fetchResponse()])(
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 }), fc.fetchResponse()])(
     'when the page cannot be loaded',
     async (key, response) => {
       const fetch = fetchMock.sandbox().getOnce(
diff --git a/test/privacy-policy.test.ts b/test/privacy-policy.test.ts
index 704de3172..e85a22468 100644
--- a/test/privacy-policy.test.ts
+++ b/test/privacy-policy.test.ts
@@ -9,7 +9,7 @@ import * as fc from './fc.js'
 import { shouldNotBeCalled } from './should-not-be-called.js'
 
 describe('privacyPolicy', () => {
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 })])('when the page can be loaded', async key => {
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 })])('when the page can be loaded', async key => {
     const fetch = fetchMock.sandbox().getOnce(
       {
         url: 'https://content.prereview.org/ghost/api/content/pages/6154aa157741400e8722bb0f',
@@ -32,7 +32,7 @@ describe('privacyPolicy', () => {
     })
   })
 
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.fetchResponse()])(
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 }), fc.fetchResponse()])(
     'when the page cannot be loaded',
     async (key, response) => {
       const fetch = fetchMock.sandbox().getOnce(
diff --git a/test/resources.test.ts b/test/resources.test.ts
index 69a3e25bd..ef1280fc9 100644
--- a/test/resources.test.ts
+++ b/test/resources.test.ts
@@ -9,7 +9,7 @@ import * as fc from './fc.js'
 import { shouldNotBeCalled } from './should-not-be-called.js'
 
 describe('resources', () => {
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 })])('when the page can be loaded', async key => {
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 })])('when the page can be loaded', async key => {
     const fetch = fetchMock.sandbox().getOnce(
       {
         url: 'https://content.prereview.org/ghost/api/content/pages/6526c6ae07fb34a92c7f8d6f',
@@ -32,7 +32,7 @@ describe('resources', () => {
     })
   })
 
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.fetchResponse()])(
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 }), fc.fetchResponse()])(
     'when the page cannot be loaded',
     async (key, response) => {
       const fetch = fetchMock.sandbox().getOnce(
diff --git a/test/slack.test.ts b/test/slack.test.ts
index 0f7b5b007..e02258eb4 100644
--- a/test/slack.test.ts
+++ b/test/slack.test.ts
@@ -12,7 +12,7 @@ import * as fc from './fc.js'
 import { shouldNotBeCalled } from './should-not-be-called.js'
 
 describe('getUserFromSlack', () => {
-  test.prop([fc.string(), fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.nonEmptyString(), fc.url()])(
+  test.prop([fc.string(), fc.string({ unit: fc.alphanumeric(), minLength: 1 }), fc.nonEmptyString(), fc.url()])(
     'when the user can be decoded',
     async (slackApiToken, user, name, image) => {
       const fetch = fetchMock.sandbox().getOnce(
@@ -44,7 +44,7 @@ describe('getUserFromSlack', () => {
 
   test.prop([
     fc.string(),
-    fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
     fc.fetchResponse({ status: fc.constant(Status.OK) }),
   ])("when the user can't be decoded", async (slackApiToken, user, response) => {
     const fetch = fetchMock.sandbox().getOnce(
@@ -67,7 +67,7 @@ describe('getUserFromSlack', () => {
     expect(fetch.done()).toBeTruthy()
   })
 
-  test.prop([fc.string(), fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.nonEmptyString()])(
+  test.prop([fc.string(), fc.string({ unit: fc.alphanumeric(), minLength: 1 }), fc.nonEmptyString()])(
     'when the response has a Slack error',
     async (slackApiToken, user, error) => {
       const fetch = fetchMock.sandbox().getOnce(
@@ -93,7 +93,7 @@ describe('getUserFromSlack', () => {
 
   test.prop([
     fc.string(),
-    fc.stringOf(fc.alphanumeric(), { minLength: 1 }),
+    fc.string({ unit: fc.alphanumeric(), minLength: 1 }),
     fc.integer({ min: 200, max: 599 }).filter(status => status !== Status.OK),
   ])('when the response has a non-200 status code', async (slackApiToken, user, status) => {
     const fetch = fetchMock.sandbox().getOnce(
@@ -116,7 +116,7 @@ describe('getUserFromSlack', () => {
     expect(fetch.done()).toBeTruthy()
   })
 
-  test.prop([fc.string(), fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.error()])(
+  test.prop([fc.string(), fc.string({ unit: fc.alphanumeric(), minLength: 1 }), fc.error()])(
     'when fetch throws an error',
     async (slackApiToken, user, error) => {
       const actual = await _.getUserFromSlack(user)({
diff --git a/test/trainings.test.ts b/test/trainings.test.ts
index 6ed681cff..fb48ab5e6 100644
--- a/test/trainings.test.ts
+++ b/test/trainings.test.ts
@@ -9,7 +9,7 @@ import * as fc from './fc.js'
 import { shouldNotBeCalled } from './should-not-be-called.js'
 
 describe('trainings', () => {
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 })])('when the page can be loaded', async key => {
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 })])('when the page can be loaded', async key => {
     const fetch = fetchMock.sandbox().getOnce(
       {
         url: 'https://content.prereview.org/ghost/api/content/pages/64639b5007fb34a92c7f8518',
@@ -32,7 +32,7 @@ describe('trainings', () => {
     })
   })
 
-  test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 }), fc.fetchResponse()])(
+  test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 }), fc.fetchResponse()])(
     'when the page cannot be loaded',
     async (key, response) => {
       const fetch = fetchMock.sandbox().getOnce(
diff --git a/test/types/string.test.ts b/test/types/string.test.ts
index 2940d3055..3e7b0fbe6 100644
--- a/test/types/string.test.ts
+++ b/test/types/string.test.ts
@@ -6,13 +6,13 @@ import * as fc from '../fc.js'
 
 describe('NonEmptyStringC', () => {
   describe('decode', () => {
-    test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 })])('with a non-empty string', string => {
+    test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 })])('with a non-empty string', string => {
       const actual = _.NonEmptyStringC.decode(string)
 
       expect(actual).toStrictEqual(D.success(string))
     })
 
-    test.prop([fc.stringOf(fc.invisibleCharacter())])('with an empty string', string => {
+    test.prop([fc.string({ unit: fc.invisibleCharacter() })])('with an empty string', string => {
       const actual = _.NonEmptyStringC.decode(string)
 
       expect(actual).toStrictEqual(D.failure(string, 'NonEmptyString'))
@@ -34,11 +34,11 @@ describe('NonEmptyStringC', () => {
 
 describe('isNonEmptyString', () => {
   describe('decode', () => {
-    test.prop([fc.stringOf(fc.alphanumeric(), { minLength: 1 })])('with a non-empty string', string => {
+    test.prop([fc.string({ unit: fc.alphanumeric(), minLength: 1 })])('with a non-empty string', string => {
       expect(_.isNonEmptyString(string)).toBe(true)
     })
 
-    test.prop([fc.stringOf(fc.invisibleCharacter())])('with an empty string', string => {
+    test.prop([fc.string({ unit: fc.invisibleCharacter() })])('with an empty string', string => {
       expect(_.isNonEmptyString(string)).toBe(false)
     })
   })