diff --git a/server/src/core/user-core.ts b/server/src/core/user-core.ts
new file mode 100644
index 000000000..b16efa7b0
--- /dev/null
+++ b/server/src/core/user-core.ts
@@ -0,0 +1,75 @@
+import { PrivateUserDocument, PublicUserDocument } from "kamaitachi-common";
+import db from "../db";
+
+const PRIVATE_USER_RETURNS = {
+    password: 0,
+    email: 0,
+    // legacy protection - this field does not exist on user documents anymore, but it did, and it *did* hold personal information.
+    integrations: 0,
+};
+
+/**
+ * Gets a user based on their username case-insensitively.
+ * @param username The username of the user.
+ * @returns PublicUserDocument
+ */
+export function GetUserCaseInsensitive(username: string) {
+    return db.get<PrivateUserDocument>("users").findOne(
+        {
+            usernameLowercase: username.toLowerCase(),
+        },
+        {
+            projection: PRIVATE_USER_RETURNS,
+        }
+    );
+}
+
+/**
+ * Returns GetUserCaseInsensitive, but without the private field omission.
+ * @see GetUserCaseInsensitive
+ * @param username The username of the user.
+ * @returns PrivateUserDocument
+ */
+export function PRIVATEINFO_GetUserCaseInsensitive(username: string) {
+    return db.get<PrivateUserDocument>("users").findOne({
+        usernameLowercase: username.toLowerCase(),
+    });
+}
+
+/**
+ * Returns a formatted string indicating the user. This is used for logging.
+ * @param userdoc The user document to format.
+ */
+export function FormatUserDoc(userdoc: PublicUserDocument) {
+    return `${userdoc.username} (~${userdoc.id})`;
+}
+
+/**
+ * Gets a user based on either their username case-insensitively, or a direct lookup of their ID.
+ * This is used in URLs to resolve the passed user.
+ * @param usernameOrID
+ */
+export function ResolveUser(usernameOrID: string) {
+    // user ID passed
+    if (usernameOrID.match(/^[0-9]$/)) {
+        let intID = parseInt(usernameOrID, 10);
+
+        return db.get<PrivateUserDocument>("users").findOne(
+            {
+                id: intID,
+            },
+            {
+                projection: PRIVATE_USER_RETURNS,
+            }
+        );
+    }
+
+    return db.get<PrivateUserDocument>("users").findOne(
+        {
+            usernameLowercase: usernameOrID,
+        },
+        {
+            projection: PRIVATE_USER_RETURNS,
+        }
+    );
+}