Case Study
•Re-architecting a Legacy Chrome Extension
Re-architecting a Legacy Chrome Extension
Rewriting a complex production Chrome extension to eliminate duplication, improve maintainability, and reduce feature delivery time from weeks to days.
Context & Problem
Ringover’s Chrome extension enabled users to extract LinkedIn profile and list data, enrich it using multiple third-party providers (such as Lusha, Kaspr, Cognism, and others), and export the enriched data into various CRMs. Over time, as new enrichment services, CRM integrations, and fields were added, the codebase grew organically without a strong architectural foundation.
The legacy extension had grown to approximately 35k lines of code and suffered from heavy duplication, tightly coupled logic, and inconsistent handling of enrichment flows across CRM integrations. Each CRM had its own implementation, with similar logic repeated in multiple places. As a result, even small changes—such as adding a new enrichment provider, field, or UI update—could take up to two weeks to ship, and debugging or onboarding new developers was increasingly difficult.
Key Engineering Decisions
Rewrite Instead of Incremental Refactor
After evaluating the existing codebase, I concluded that incremental refactoring would be slower and riskier than a rewrite. The foundational issues—lack of clear boundaries and widespread duplication—meant meaningful improvements required rethinking the structure from the ground up.
Single Source of Truth for Enrichment Logic
I redesigned the extension so that enrichment fields and core logic were defined once and reused across all CRM integrations. Instead of separate enrichment flows per CRM, shared functions handled the core behavior, with only minimal, well-scoped customization where required.
Gradual Rollout to Reduce Risk
To avoid disrupting users, the rewritten extension was first released internally. Once stability was confirmed, the legacy extension was gradually deprecated and users were migrated incrementally, ensuring a safe transition without breaking existing workflows.
Business Impact
Significant reduction by removing duplication and simplifying architecture
New features and changes could be shipped in a couple of days instead of ~2 weeks
Bug rates decreased, debugging became easier, and new developers were able to understand and contribute to the codebase much faster
What I'd improve at 10× scale
If the extension continues to grow in scope, the next step would be to further modularize enrichment providers and introduce stronger type-level guarantees for field mappings. This would make onboarding new integrations even safer and reduce the risk of regressions as the product evolves.