Account Integration Solutions for 58 Group: Merging, Linking, and Cloud Account Platform

In recent years, 58 Group has rapidly expanded through mergers and acquisitions, resulting in many subsidiaries each maintaining independent account systems; unifying these accounts is essential for resource optimization and ecosystem integration.

The main requirements include joint login (users logged in on one site should be logged in on another) and resource sharing (systems on one site should be able to access user data on another).

Technical Solution 1: Account System Merging

This approach consolidates multiple independent account databases into a single system, eliminating the need for cross‑system login. It typically involves importing one side's data into the other, handling conflicts (e.g., duplicate usernames, mismatched phone/email bindings), and possibly using a CAS single sign‑on solution for multi‑domain access.

Challenges include data conflicts (identical usernames, inconsistent phone/email bindings, third‑party OpenID mismatches) and the need to adjust downstream business systems or maintain a mapping between old and new user IDs.

Although merging offers a thorough solution, it requires careful product design decisions and user consent to avoid complaints.

Technical Solution 2: Account Linking (Association)

Instead of merging, each system remains independent while establishing a link between corresponding accounts, enabling joint login and resource sharing. Users can voluntarily associate accounts, avoiding data conflicts and minimizing user complaints.

Benefits include no need to modify business systems, only the account services, and the ability to query association data for authentication.

The most common implementation uses an open platform (e.g., WeChat or QQ) with OAuth2.0 authorization codes to securely transmit login information between systems.

Extensions to bidirectional login are possible but require cooperation from third‑party platforms.

Key points include implicit authorization to reduce user prompts, automatic triggering of login on the partner site after a successful login, and synchronized storage of user‑ID to OpenID mappings.

Server‑side resource access can be secured using the open platform's authentication mechanisms.

While this method is cost‑effective, it introduces security concerns (a breach on one side compromises the linked account) and redundancy due to multiple similar systems.

Technical Solution 3: Cloud Account Platform

To address security and redundancy, a unified cloud account platform centralizes core account capabilities and security, while preserving logical independence of each subsidiary's data.

This architecture simplifies future feature rollout, reduces integration costs, and makes subsequent merging or linking operations much easier.

In summary, the article shares 58 Group's practical experiences with account integration, highlighting pain points, technical challenges, and three solution paths—merging, linking, and a cloud‑based unified platform—offering insights for other fast‑growing internet companies facing similar problems.

58's first blockchain application is also showcased.