diff --git a/modules/identities/db/migrations/20240703025745_/migration.sql b/modules/identities/db/migrations/20240703025745_/migration.sql
new file mode 100644
index 00000000..b56987b6
--- /dev/null
+++ b/modules/identities/db/migrations/20240703025745_/migration.sql
@@ -0,0 +1,22 @@
+-- CreateTable
+CREATE TABLE "UserIdentities" (
+    "userId" UUID NOT NULL,
+    "identityType" TEXT NOT NULL,
+    "identityId" TEXT NOT NULL,
+    "uniqueData" JSONB NOT NULL,
+    "additionalData" JSONB NOT NULL,
+
+    CONSTRAINT "UserIdentities_pkey" PRIMARY KEY ("userId","identityType","identityId")
+);
+
+-- CreateIndex
+CREATE INDEX "UserIdentities_userId_idx" ON "UserIdentities"("userId");
+
+-- CreateIndex
+CREATE INDEX "UserIdentities_identityType_identityId_idx" ON "UserIdentities"("identityType", "identityId");
+
+-- CreateIndex
+CREATE INDEX "UserIdentities_identityType_identityId_uniqueData_idx" ON "UserIdentities"("identityType", "identityId", "uniqueData");
+
+-- CreateIndex
+CREATE UNIQUE INDEX "UserIdentities_identityType_identityId_uniqueData_key" ON "UserIdentities"("identityType", "identityId", "uniqueData");
diff --git a/modules/identities/db/migrations/migration_lock.toml b/modules/identities/db/migrations/migration_lock.toml
new file mode 100644
index 00000000..fbffa92c
--- /dev/null
+++ b/modules/identities/db/migrations/migration_lock.toml
@@ -0,0 +1,3 @@
+# Please do not edit this file manually
+# It should be added in your version-control system (i.e. Git)
+provider = "postgresql"
\ No newline at end of file
diff --git a/modules/identities/db/schema.prisma b/modules/identities/db/schema.prisma
new file mode 100644
index 00000000..aaa51b8a
--- /dev/null
+++ b/modules/identities/db/schema.prisma
@@ -0,0 +1,27 @@
+// Do not modify this `datasource` block
+datasource db {
+	provider = "postgresql"
+	url      = env("DATABASE_URL")
+}
+
+model UserIdentities {
+    userId          String      @db.Uuid
+
+	// Used to identify the user from the identity
+	identityType    String
+	identityId      String
+	uniqueData      Json
+
+	additionalData  Json
+
+	// Additional indexes for speed
+	@@index([userId])
+	@@index([identityType, identityId])
+
+	// Each user should only have one identity per (type, id) pair (for now)
+	@@id([userId, identityType, identityId])
+
+	// Each identity should only be linked to one user
+	@@index([identityType, identityId, uniqueData])
+	@@unique([identityType, identityId, uniqueData])
+}
diff --git a/modules/identities/module.json b/modules/identities/module.json
new file mode 100644
index 00000000..056362bd
--- /dev/null
+++ b/modules/identities/module.json
@@ -0,0 +1,64 @@
+{
+    "name": "Identites",
+    "description": "Manage identities and identity data for users.",
+    "icon": "key",
+    "tags": [
+        "core",
+        "user",
+        "auth"
+    ],
+    "authors": [
+        "rivet-gg",
+        "Blckbrry-Pi"
+    ],
+    "status": "beta",
+    "dependencies": {
+        "rate_limit": {},
+        "users": {},
+        "tokens": {}
+    },
+    "scripts": {
+        "list": {
+            "name": "List Identities",
+            "description": "List all identities the user is associated with.",
+            "public": true
+        },
+        "get": {
+            "name": "Get Identity Data",
+            "description": "Get the data associated with a specific identity for a user."
+        },
+        "set": {
+            "name": "Set Identity Data",
+            "description": "Set the data associated with a specific identity for a user."
+        },
+
+        "sign_in": {
+            "name": "Sign In With Identity",
+            "description": "Sign in to a user with an identity."
+        },
+        "sign_up": {
+            "name": "Sign Up With Identity",
+            "description": "Sign up with an identity. Creates a new user."
+        },
+        "sign_in_or_sign_up": {
+            "name": "Sign In or Sign Up With Identity",
+            "description": "Sign in to a user with an identity, creating a new user if it fails."
+        },
+        "link": {
+            "name": "Link Identity To User",
+            "description": "Link a new identity and its associated data to a user. This is used for login and non-login identites."
+        }
+    },
+    "routes": {},
+    "errors": {
+        "identity_provider_not_found": {
+            "name": "Identity Provider Not Found"
+        },
+        "identity_provider_already_added": {
+            "name": "Identity Provider Already Added To User"
+        },
+        "identity_provider_already_used": {
+            "name": "Identity Provider Already Used By Other User"
+        }
+    }
+}
\ No newline at end of file
diff --git a/modules/identities/scripts/get.ts b/modules/identities/scripts/get.ts
new file mode 100644
index 00000000..2013fdc5
--- /dev/null
+++ b/modules/identities/scripts/get.ts
@@ -0,0 +1,58 @@
+import { ScriptContext } from "../module.gen.ts";
+import { IdentityData, IdentityProviderInfo } from "../utils/types.ts";
+
+export interface Request {
+	userToken: string;
+    info: IdentityProviderInfo;
+}
+
+export interface Response {
+    data: {
+        uniqueData: IdentityData;
+        additionalData: IdentityData;
+    } | null;
+}
+
+export async function run(
+	ctx: ScriptContext,
+	req: Request,
+): Promise<Response> {
+	await ctx.modules.rateLimit.throttle({
+        key: req.userToken,
+        period: 10,
+        requests: 10,
+        type: "user",
+    });
+
+    // Ensure the user token is valid and get the user ID
+    const { userId } = await ctx.modules.users.authenticateToken({ userToken: req.userToken } );
+
+    // Get identity data
+    const identity = await ctx.db.userIdentities.findFirst({
+        where: {
+            userId,
+            identityType: req.info.identityType,
+            identityId: req.info.identityId,
+        },
+        select: {
+            uniqueData: true,
+            additionalData: true
+        }
+    });
+
+    // Type checking to make typescript happy
+    const data = identity ?? null;
+    if (!data) {
+        return { data: null };
+    }
+
+    const { uniqueData, additionalData } = data;
+    if (typeof uniqueData !== 'object' || Array.isArray(uniqueData) || uniqueData === null) {
+        return { data: null };
+    }
+    if (typeof additionalData !== 'object' || Array.isArray(additionalData) || additionalData === null) {
+        return { data: null };
+    }
+
+    return { data: { uniqueData, additionalData } };
+}
diff --git a/modules/identities/scripts/link.ts b/modules/identities/scripts/link.ts
new file mode 100644
index 00000000..025a0c2c
--- /dev/null
+++ b/modules/identities/scripts/link.ts
@@ -0,0 +1,45 @@
+import { RuntimeError, ScriptContext } from "../module.gen.ts";
+import { IdentityDataInput, IdentityProviderInfo } from "../utils/types.ts";
+
+export interface Request {
+	userToken: string;
+    info: IdentityProviderInfo;
+    uniqueData: IdentityDataInput;
+    additionalData: IdentityDataInput;
+}
+
+export interface Response {
+	identityProviders: IdentityProviderInfo[];
+}
+
+export async function run(
+	ctx: ScriptContext,
+	req: Request,
+): Promise<Response> {
+	await ctx.modules.rateLimit.throttle({
+        key: req.userToken,
+        period: 10,
+        requests: 10,
+        type: "user",
+    });
+
+    // Ensure the user token is valid and get the user ID
+    const { userId } = await ctx.modules.users.authenticateToken({ userToken: req.userToken } );
+
+    // Error if this identity provider is ALREADY associated with the user
+    const { data: prevData } = await ctx.modules.identities.get({ userToken: req.userToken, info: req.info });
+    if (prevData) throw new RuntimeError("identity_provider_already_added");
+
+    // Add a new entry to the table with the associated data
+    await ctx.db.userIdentities.create({
+        data: {
+            userId,
+            identityType: req.info.identityType,
+            identityId: req.info.identityId,
+            uniqueData: req.uniqueData,
+            additionalData: req.additionalData,
+        },
+    });
+
+    return await ctx.modules.identities.list({ userToken: req.userToken });
+}
diff --git a/modules/identities/scripts/list.ts b/modules/identities/scripts/list.ts
new file mode 100644
index 00000000..3142829a
--- /dev/null
+++ b/modules/identities/scripts/list.ts
@@ -0,0 +1,33 @@
+import { ScriptContext } from "../module.gen.ts";
+import { IdentityProviderInfo } from "../utils/types.ts";
+
+export interface Request {
+	userToken: string;
+}
+
+export interface Response {
+    identityProviders: IdentityProviderInfo[];
+}
+
+export async function run(
+	ctx: ScriptContext,
+	req: Request,
+): Promise<Response> {
+	await ctx.modules.rateLimit.throttlePublic({});
+
+    // Ensure the user token is valid and get the user ID
+    const { userId } = await ctx.modules.users.authenticateToken({ userToken: req.userToken } );
+
+    // Select identityType and identityId entries that match the userId
+    const identityProviders = await ctx.db.userIdentities.findMany({
+        where: {
+            userId,
+        },
+        select: {
+            identityType: true,
+            identityId: true,
+        }
+    });
+
+    return { identityProviders };
+}
diff --git a/modules/identities/scripts/set.ts b/modules/identities/scripts/set.ts
new file mode 100644
index 00000000..0c53a49d
--- /dev/null
+++ b/modules/identities/scripts/set.ts
@@ -0,0 +1,48 @@
+import { ScriptContext, Empty, RuntimeError } from "../module.gen.ts";
+import { IdentityDataInput, IdentityProviderInfo } from "../utils/types.ts";
+
+export interface Request {
+	userToken: string;
+    info: IdentityProviderInfo;
+    uniqueData?: IdentityDataInput;
+    additionalData: IdentityDataInput;
+}
+
+export type Response = Empty;
+
+export async function run(
+	ctx: ScriptContext,
+	req: Request,
+): Promise<Response> {
+	await ctx.modules.rateLimit.throttle({
+        key: req.userToken,
+        period: 10,
+        requests: 10,
+        type: "user",
+    });
+
+    // Ensure the user token is valid and get the user ID
+    const { userId } = await ctx.modules.users.authenticateToken({ userToken: req.userToken } );
+
+    // Error if this identity provider is not associated with the user
+    const { data: prevData } = await ctx.modules.identities.get({ userToken: req.userToken, info: req.info });
+    if (!prevData) throw new RuntimeError("identity_provider_not_found");
+
+
+    // Update the identity data where userId, identityType, and identityId match
+    await ctx.db.userIdentities.update({
+        where: {
+            userId_identityType_identityId: {
+                userId,
+                identityType: req.info.identityType,
+                identityId: req.info.identityId,
+            }
+        },
+        data: {
+            uniqueData: req.uniqueData,
+            additionalData: req.additionalData,
+        },
+    });
+
+    return {};
+}
diff --git a/modules/identities/scripts/sign_in.ts b/modules/identities/scripts/sign_in.ts
new file mode 100644
index 00000000..53cd14f1
--- /dev/null
+++ b/modules/identities/scripts/sign_in.ts
@@ -0,0 +1,46 @@
+import { ScriptContext } from "../module.gen.ts";
+import { IdentityDataInput, IdentityProviderInfo } from "../utils/types.ts";
+
+export interface Request {
+    info: IdentityProviderInfo;
+    uniqueData: IdentityDataInput;
+}
+
+export interface Response {
+    userToken: string;
+}
+
+export async function run(
+	ctx: ScriptContext,
+	req: Request,
+): Promise<Response> {
+    const key = req.info.identityType + ":" + req.info.identityId + ":" + JSON.stringify(req.uniqueData);
+	await ctx.modules.rateLimit.throttle({
+        key,
+        period: 10,
+        requests: 10,
+        type: "user",
+    });
+
+    // Get users the provider is associated with
+    const identity = await ctx.db.userIdentities.findFirst({
+        where: {
+            identityType: req.info.identityType,
+            identityId: req.info.identityId,
+            uniqueData: { equals: req.uniqueData },
+        },
+        select: {
+            userId: true,
+        },
+    });
+
+    // If the provider info/uniqueData combo is not associated with a user,
+    // throw provider_not_found error.
+    if (!identity) {
+        throw new Error("identity_not_found");
+    }
+
+    // Generate a user token
+    const { token: { token } } = await ctx.modules.users.createToken({ userId: identity.userId });
+    return { userToken: token };
+}
diff --git a/modules/identities/scripts/sign_in_or_sign_up.ts b/modules/identities/scripts/sign_in_or_sign_up.ts
new file mode 100644
index 00000000..eba07c09
--- /dev/null
+++ b/modules/identities/scripts/sign_in_or_sign_up.ts
@@ -0,0 +1,38 @@
+import { RuntimeError, ScriptContext } from "../module.gen.ts";
+import { IdentityDataInput, IdentityProviderInfo } from "../utils/types.ts";
+
+export interface Request {
+    info: IdentityProviderInfo;
+    uniqueData: IdentityDataInput;
+    additionalData: IdentityDataInput;
+
+    username?: string;
+}
+
+export interface Response {
+    userToken: string;
+}
+
+export async function run(
+	ctx: ScriptContext,
+	req: Request,
+): Promise<Response> {
+    try {
+        return await ctx.modules.identities.signIn({
+            info: req.info,
+            uniqueData: req.uniqueData,
+        });
+    } catch (e) {
+        if (e instanceof RuntimeError) {
+            if (e.code === "identity_not_found") {
+                return await ctx.modules.identities.signUp({
+                    info: req.info,
+                    uniqueData: req.uniqueData,
+                    additionalData: req.additionalData,
+                    username: req.username,
+                });
+            }
+        }
+        throw e;
+    }
+}
diff --git a/modules/identities/scripts/sign_up.ts b/modules/identities/scripts/sign_up.ts
new file mode 100644
index 00000000..382be459
--- /dev/null
+++ b/modules/identities/scripts/sign_up.ts
@@ -0,0 +1,63 @@
+import { RuntimeError, ScriptContext } from "../module.gen.ts";
+import { IdentityDataInput, IdentityProviderInfo } from "../utils/types.ts";
+
+export interface Request {
+    info: IdentityProviderInfo;
+    uniqueData: IdentityDataInput;
+    additionalData: IdentityDataInput;
+
+    username?: string;
+}
+
+export interface Response {
+    userToken: string;
+}
+
+export async function run(
+	ctx: ScriptContext,
+	req: Request,
+): Promise<Response> {
+    const key = req.info.identityType + ":" + req.info.identityId + ":" + JSON.stringify(req.uniqueData);
+	await ctx.modules.rateLimit.throttle({
+        key,
+        period: 10,
+        requests: 10,
+        type: "user",
+    });
+
+    // Get users the provider is associated with
+    const identity = await ctx.db.userIdentities.findFirst({
+        where: {
+            identityType: req.info.identityType,
+            identityId: req.info.identityId,
+            uniqueData: { equals: req.uniqueData },
+        },
+        select: {
+            userId: true,
+        },
+    });
+
+    // If the identity provider is associated with a user, throw an error
+    if (identity) {
+        throw new RuntimeError("identity_provider_already_used");
+    }
+
+    // Create a new user
+    const { user } = await ctx.modules.users.create({ username: req.username });
+
+    // Insert the identity data with the newly-created user
+    await ctx.db.userIdentities.create({
+        data: {
+            userId: user.id,
+            identityType: req.info.identityType,
+            identityId: req.info.identityId,
+            uniqueData: req.uniqueData,
+            additionalData: req.additionalData,
+        },
+    });
+
+    // Generate a user token and return it
+    const { token: { token } } = await ctx.modules.users.createToken({ userId: user.id });
+
+    return { userToken: token };
+}
diff --git a/modules/identities/tests/data.ts b/modules/identities/tests/data.ts
new file mode 100644
index 00000000..5b6b76f5
--- /dev/null
+++ b/modules/identities/tests/data.ts
@@ -0,0 +1,66 @@
+import { test, TestContext } from "../module.gen.ts";
+import { assertExists, assertEquals } from "https://deno.land/std@0.217.0/assert/mod.ts";
+import { faker } from "https://deno.land/x/deno_faker@v1.0.3/mod.ts";
+import { signInWithTest, signUpWithTest } from "./sign_up.ts";
+
+test("Test Data Modification", async (ctx: TestContext) => {
+    const username = faker.internet.userName();
+    const uniqueData = { unique: faker.random.alphaNumeric(10) };
+    const additionalData = { additional: faker.random.alphaNumeric(100) };
+
+    const signUpRes = await signUpWithTest(
+        ctx,
+        username,
+        uniqueData,
+        additionalData,
+    );
+
+    // Validate the identity data
+    {
+        const { data } = await ctx.modules.identities.get({
+            userToken: signUpRes.userToken,
+            info: {
+                identityType: "test",
+                identityId: "test",
+            },
+        });
+        assertExists(data);
+        assertEquals(data.uniqueData, uniqueData);
+        assertEquals(data.additionalData, additionalData);
+    }
+
+    // Sign in with the same identity and verify that the user is the same
+    const signInRes = await signInWithTest(ctx, uniqueData);
+    assertEquals(signUpRes.userId, signInRes.userId);
+    assertEquals(signUpRes.user, signInRes.user);
+
+
+    // Modify the identity data
+    const newUniqueData = { unique: faker.random.alphaNumeric(10) };
+    const newAdditionalData = { additional: faker.random.alphaNumeric(100) };
+
+    await ctx.modules.identities.set({
+        userToken: signUpRes.userToken,
+        info: {
+            identityType: "test",
+            identityId: "test",
+        },
+        uniqueData: newUniqueData,
+        additionalData: newAdditionalData,
+    });
+
+
+    // Validate the identity data
+    {
+        const { data } = await ctx.modules.identities.get({
+            userToken: signUpRes.userToken,
+            info: {
+                identityType: "test",
+                identityId: "test",
+            },
+        });
+        assertExists(data);
+        assertEquals(data.uniqueData, newUniqueData);
+        assertEquals(data.additionalData, newAdditionalData);
+    }
+});
diff --git a/modules/identities/tests/link.ts b/modules/identities/tests/link.ts
new file mode 100644
index 00000000..016ec69c
--- /dev/null
+++ b/modules/identities/tests/link.ts
@@ -0,0 +1,75 @@
+import { test, TestContext } from "../module.gen.ts";
+import { assertExists, assertEquals } from "https://deno.land/std@0.217.0/assert/mod.ts";
+import { faker } from "https://deno.land/x/deno_faker@v1.0.3/mod.ts";
+import { signInWithTest, signUpWithTest } from "./sign_up.ts";
+
+test("Link a new identity to an existing user", async (ctx: TestContext) => {
+    const username = faker.internet.userName();
+
+    const uniqueData = { unique: faker.random.alphaNumeric(10) };
+    const additionalData = { additional: faker.random.alphaNumeric(100) };
+
+    const signUpRes = await signUpWithTest(
+        ctx,
+        username,
+        uniqueData,
+        additionalData,
+    );
+
+    // Validate the identity data
+    {
+        const { data } = await ctx.modules.identities.get({
+            userToken: signUpRes.userToken,
+            info: {
+                identityType: "test",
+                identityId: "test",
+            },
+        });
+        assertExists(data);
+        assertEquals(data.uniqueData, uniqueData);
+        assertEquals(data.additionalData, additionalData);
+    }
+
+    // Sign in with the same identity and verify that the user is the same
+    const signInRes = await signInWithTest(ctx, uniqueData);
+    assertEquals(signUpRes.userId, signInRes.userId);
+    assertEquals(signUpRes.user, signInRes.user);
+
+
+    // Link a new identity to the existing user
+    const newUniqueData = { unique: faker.random.alphaNumeric(10) };
+    const newAdditionalData = { additional: faker.random.alphaNumeric(100) };
+    await ctx.modules.identities.link({
+        userToken: signUpRes.userToken,
+        info: {
+            identityType: "test2",
+            identityId: "test2",
+        },
+        uniqueData: newUniqueData,
+        additionalData: newAdditionalData,
+    });
+
+    // Validate the new identity data
+    {
+        const { data } = await ctx.modules.identities.get({
+            userToken: signUpRes.userToken,
+            info: {
+                identityType: "test2",
+                identityId: "test2",
+            },
+        });
+        assertExists(data);
+        assertEquals(data.uniqueData, newUniqueData);
+        assertEquals(data.additionalData, newAdditionalData);
+    }
+
+    // List all identity providers and verify that both are present and both match
+    const { identityProviders } = await ctx.modules.identities.list({ userToken: signUpRes.userToken });
+
+    assertEquals(identityProviders.length, 2);
+    const [first, second] = identityProviders;
+    const [test, test2] = [first, second].sort((a, b) => a.identityType.localeCompare(b.identityType));
+
+    assertEquals(test, { identityId: "test", identityType: "test" });
+    assertEquals(test2, { identityId: "test2", identityType: "test2" });
+});
diff --git a/modules/identities/tests/sign_up.ts b/modules/identities/tests/sign_up.ts
new file mode 100644
index 00000000..d8a05f43
--- /dev/null
+++ b/modules/identities/tests/sign_up.ts
@@ -0,0 +1,77 @@
+import { test, TestContext } from "../module.gen.ts";
+import { assertExists, assertEquals } from "https://deno.land/std@0.217.0/assert/mod.ts";
+import { faker } from "https://deno.land/x/deno_faker@v1.0.3/mod.ts";
+
+// deno-lint-ignore no-explicit-any
+export async function signUpWithTest(ctx: TestContext, username: string, uniqueData: any, additionalData: any) {
+    const { userToken } = await ctx.modules.identities.signUp({
+        info: {
+            identityType: "test",
+            identityId: "test",
+        },
+        username,
+        uniqueData,
+        additionalData,
+    });
+
+    const { userId, user } = await ctx.modules.users.authenticateToken({
+        userToken,
+        fetchUser: true,
+    });
+    assertExists(user);
+    assertEquals(user.username, username);
+
+    return { userToken, userId, user };
+}
+
+// deno-lint-ignore no-explicit-any
+export async function signInWithTest(ctx: TestContext, uniqueData: any) {
+    const { userToken } = await ctx.modules.identities.signIn({
+        info: {
+            identityType: "test",
+            identityId: "test",
+        },
+        uniqueData,
+    });
+
+    const { userId, user } = await ctx.modules.users.authenticateToken({
+        userToken,
+        fetchUser: true,
+    });
+    assertExists(user);
+
+    return { userToken, userId, user };
+}
+
+test("Sign Up and Sign In", async (ctx: TestContext) => {
+    const username = faker.internet.userName();
+
+    const uniqueData = { unique: faker.random.alphaNumeric(10) };
+    const additionalData = { additional: faker.random.alphaNumeric(100) };
+
+    const signUpRes = await signUpWithTest(
+        ctx,
+        username,
+        uniqueData,
+        additionalData,
+    );
+
+    // Validate the identity data
+    {
+        const { data } = await ctx.modules.identities.get({
+            userToken: signUpRes.userToken,
+            info: {
+                identityType: "test",
+                identityId: "test",
+            },
+        });
+        assertExists(data);
+        assertEquals(data.uniqueData, uniqueData);
+        assertEquals(data.additionalData, additionalData);
+    }
+
+    // Sign in with the same identity and verify that the user is the same
+    const signInRes = await signInWithTest(ctx, uniqueData);
+    assertEquals(signUpRes.userId, signInRes.userId);
+    assertEquals(signUpRes.user, signInRes.user);
+});
diff --git a/modules/identities/utils/types.ts b/modules/identities/utils/types.ts
new file mode 100644
index 00000000..b91b32a8
--- /dev/null
+++ b/modules/identities/utils/types.ts
@@ -0,0 +1,9 @@
+import { prisma } from "../module.gen.ts";
+
+export type IdentityData = Record<string, unknown>;
+export type IdentityDataInput = IdentityData & prisma.Prisma.InputJsonValue;
+
+export interface IdentityProviderInfo {
+    identityType: string;
+    identityId: string;
+}
diff --git a/tests/basic/backend.json b/tests/basic/backend.json
index 897a398e..54898cf3 100644
--- a/tests/basic/backend.json
+++ b/tests/basic/backend.json
@@ -38,6 +38,9 @@
                 }
             }
         },
+        "identities": {
+            "registry": "local"
+        },
         "email": {
             "registry": "local",
             "config": {