diff --git a/webapp/components/utils/UniqueSlugForm.spec.js b/webapp/components/utils/UniqueSlugForm.spec.js
new file mode 100644
index 000000000..de0e3fee6
--- /dev/null
+++ b/webapp/components/utils/UniqueSlugForm.spec.js
@@ -0,0 +1,80 @@
+import UniqueSlugForm from './UniqueSlugForm'
+import Schema from 'async-validator'
+
+let translate
+let apollo
+let currentUser
+
+beforeEach(() => {
+  translate = jest.fn(() => 'Validation error')
+  apollo = {
+    query: jest.fn().mockResolvedValue({ data: { User: [] } }),
+  }
+  currentUser = null
+})
+
+describe('UniqueSlugForm', () => {
+  let validate = object => {
+    const { formSchema } = UniqueSlugForm({ translate, apollo, currentUser })
+    const validator = new Schema(formSchema)
+    return validator.validate(object, { suppressWarning: true }).catch(({ errors }) => {
+      throw new Error(errors[0].message)
+    })
+  }
+
+  describe('regex', () => {
+    describe('non URL-safe characters, e.g. whitespaces', () => {
+      it('rejects', async () => {
+        await expect(validate({ slug: 'uh oh' })).rejects.toThrow('Validation error')
+      })
+    })
+
+    describe('alphanumeric, hyphens or underscores', () => {
+      it('validates', async () => {
+        await expect(validate({ slug: '_all-right_' })).resolves.toBeUndefined()
+      })
+    })
+  })
+
+  describe('given a currentUser with a slug', () => {
+    beforeEach(() => {
+      currentUser = { slug: 'current-user' }
+    })
+
+    describe('backend returns no user for given slug', () => {
+      beforeEach(() => {
+        apollo.query.mockResolvedValue({
+          data: { User: [] },
+        })
+      })
+
+      it('validates', async () => {
+        await expect(validate({ slug: 'slug' })).resolves.toBeUndefined()
+      })
+    })
+
+    describe('backend returns user', () => {
+      let slug
+      beforeEach(() => {
+        slug = 'already-taken'
+        apollo.query.mockResolvedValue({
+          data: { User: [{ slug: 'already-taken' }] },
+        })
+      })
+
+      it('rejects', async () => {
+        await expect(validate({ slug: 'uh oh' })).rejects.toThrow('Validation error')
+      })
+
+      describe('but it is the current user', () => {
+        beforeEach(() => {
+          currentUser = { slug: 'already-taken' }
+        })
+
+        it('validates', async () => {
+          await expect(validate({ slug })).resolves.toBeUndefined()
+        })
+      })
+    })
+  })
+})
diff --git a/webapp/package.json b/webapp/package.json
index 598412568..f18556e99 100644
--- a/webapp/package.json
+++ b/webapp/package.json
@@ -97,6 +97,7 @@
     "@vue/eslint-config-prettier": "~5.0.0",
     "@vue/server-test-utils": "~1.0.0-beta.29",
     "@vue/test-utils": "~1.0.0-beta.29",
+    "async-validator": "^3.1.0",
     "babel-core": "~7.0.0-bridge.0",
     "babel-eslint": "~10.0.3",
     "babel-jest": "~24.9.0",
diff --git a/webapp/yarn.lock b/webapp/yarn.lock
index 6fdcc9134..a86ae8527 100644
--- a/webapp/yarn.lock
+++ b/webapp/yarn.lock
@@ -3649,6 +3649,11 @@ async-retry@^1.2.1:
   dependencies:
     retry "0.12.0"
 
+async-validator@^3.1.0:
+  version "3.1.0"
+  resolved "https://registry.yarnpkg.com/async-validator/-/async-validator-3.1.0.tgz#447db5eb003cbb47e650f040037a29fc3881ce92"
+  integrity sha512-XyAHGwtpx3Y3aHIOaGXXFo4tiulnrh+mXBU9INxig6Q8rtmtmBxDuCxb60j7EIGbAsQg9cxfJ2jrUZ+fIqEnBQ==
+
 async@^2.1.4:
   version "2.6.2"
   resolved "https://registry.yarnpkg.com/async/-/async-2.6.2.tgz#18330ea7e6e313887f5d2f2a904bac6fe4dd5381"