diff --git a/packages/core/src/infrastructure/bull/bull.types.ts b/packages/core/src/infrastructure/bull/bull.types.ts
index 71e46f560..fe48f0f72 100644
--- a/packages/core/src/infrastructure/bull/bull.types.ts
+++ b/packages/core/src/infrastructure/bull/bull.types.ts
@@ -464,7 +464,7 @@ export const SlackBullJob = z.discriminatedUnion('name', [
     name: z.literal('slack.joined'),
     data: z.object({
       email: Student.shape.email,
-      slackId: Student.shape.slackId,
+      slackId: z.string().trim().min(1),
     }),
   }),
   z.object({
diff --git a/packages/core/src/modules/slack/events/slack-workspace-joined.ts b/packages/core/src/modules/slack/events/slack-workspace-joined.ts
index 2f5889a55..3b1813c0c 100644
--- a/packages/core/src/modules/slack/events/slack-workspace-joined.ts
+++ b/packages/core/src/modules/slack/events/slack-workspace-joined.ts
@@ -2,6 +2,7 @@ import { db } from '@oyster/db';
 
 import { type GetBullJobData } from '@/infrastructure/bull/bull.types';
 import { getMemberByEmail } from '@/modules/member/queries/get-member-by-email';
+import { addDirectoryLinkToSlackProfile } from '@/modules/slack/slack-profile';
 import { NotFoundError } from '@/shared/errors';
 
 export async function onSlackWorkspaceJoined({
@@ -27,4 +28,9 @@ export async function onSlackWorkspaceJoined({
     })
     .where('id', '=', member.id)
     .execute();
+
+  await addDirectoryLinkToSlackProfile({
+    id: member.id,
+    slackId,
+  });
 }
diff --git a/packages/core/src/modules/slack/slack-profile.ts b/packages/core/src/modules/slack/slack-profile.ts
new file mode 100644
index 000000000..6a8a0fb94
--- /dev/null
+++ b/packages/core/src/modules/slack/slack-profile.ts
@@ -0,0 +1,70 @@
+import { db, type DB } from '@oyster/db';
+
+import { reportException } from '@/modules/sentry/use-cases/report-exception';
+import { slack } from '@/modules/slack/instances';
+import { ENV } from '@/shared/env';
+import { RateLimiter } from '@/shared/utils/rate-limiter';
+
+// Environment Variables
+
+const SLACK_MEMBER_DIRECTORY_FIELD_ID = process.env
+  .SLACK_MEMBER_DIRECTORY_FIELD_ID as string;
+
+// Core
+
+/**
+ * @see https://api.slack.com/apis/rate-limits#tier_t3
+ */
+const updateProfileRateLimiter = new RateLimiter('slack:profile:update', {
+  rateLimit: 50,
+  rateLimitWindow: 60,
+});
+
+export async function addDirectoryLinkToSlackProfiles() {
+  const members = await db
+    .selectFrom('students')
+    .select(['email', 'id', 'slackId'])
+    .where('slackId', 'is not', null)
+    .orderBy('createdAt', 'desc')
+    .execute();
+
+  console.log(`Found ${members.length} members to update.`);
+
+  for (const member of members) {
+    console.log('Updating Slack profile...', member.email);
+
+    try {
+      await addDirectoryLinkToSlackProfile(member);
+      console.count('Updated Slack profile!');
+    } catch (e) {
+      console.count('Failed to update Slack profile.');
+      reportException(e);
+    }
+  }
+}
+
+/**
+ * Adds a member's Member Directory profile link to their Slack profile. Throws
+ * an error if the profile update fails.
+ *
+ * @param member - The member whose Slack profile we'll update.
+ */
+export async function addDirectoryLinkToSlackProfile(
+  member: Pick<DB['students'], 'id' | 'slackId'>
+) {
+  await updateProfileRateLimiter.process();
+
+  const profile = {
+    fields: {
+      [SLACK_MEMBER_DIRECTORY_FIELD_ID]: {
+        value: new URL(`/directory/${member.id}`, ENV.STUDENT_PROFILE_URL),
+      },
+    },
+  };
+
+  await slack.users.profile.set({
+    profile: JSON.stringify(profile),
+    token: ENV.SLACK_ADMIN_TOKEN,
+    user: member.slackId as string,
+  });
+}