Re-engineer — modernize legacy enterprise systems with AI you can audit
CORE Re-engineer is for enterprise applications where the business logic is right but the architecture is holding you back — the app can't scale, can't move to cloud, can't be multi-tenant, can't meet new security requirements. Re-architect the foundations; keep the logic exactly.
The system works. The architecture doesn't.
Re-engineer isn't the same as a rewrite. Rewrite (part of the Create pathway) changes the technology stack. Re-engineer changes the shape of the system itself — how it's deployed, how it scales, who can access which pieces, how tenants are separated, how it fails, how it recovers. The business logic is treated as sacred; the architecture is what changes.
Each with its own discovery, planning, and delivery pattern
These aren't marketing categories — they're the six architectural patterns most enterprise re-engineering projects actually fall into. Below is what each involves in practice.
Cloud migration
Move an on-premise or fixed-datacenter application to AWS, Azure, or GCP. CORE analyzes every host, storage, network, and service dependency; produces a target cloud architecture; and delivers the migrated system along with Terraform for the cloud environment. Includes strategy decisions like lift-and-shift vs. cloud-native refactor, per-component.
Typical duration: 12–24 weeks depending on component count and data volume.
Monolith to microservices
Break apart a decade-old monolithic codebase into independently deployable services along clean bounded-context lines. CORE identifies the natural service boundaries by analyzing data access patterns and function call graphs, proposes a target architecture, and delivers the split with proper inter-service contracts (REST or gRPC) and event streams where appropriate.
Typical duration: 14–28 weeks depending on service count.
Database modernization
Migrate from Oracle/DB2/SQL Server to Postgres or a cloud-managed database. Or move from a single-schema relational design to a partitioned/sharded/read-replica'd architecture. CORE handles the schema translation, the data migration scripts, the ORM/query layer updates, and — critically — proves data equivalence between old and new.
Typical duration: 8–20 weeks depending on data volume and complexity.
Multi-tenant transformation
Convert a single-tenant application into a multi-tenant SaaS platform. CORE identifies every point where tenant data must be isolated, adds row-level security or schema-per-tenant separation, updates authentication and authorization, and delivers tenant onboarding flows plus admin tooling for tenant management.
Typical duration: 12–24 weeks depending on data isolation model.
Security posture upgrade
An application that works but doesn't meet new security requirements — no SSO, weak audit logs, plaintext PII, insufficient RBAC, unencrypted at rest. CORE identifies every control gap against the target framework (SOC 2, ISO 27001, HIPAA, PCI-DSS), produces a remediation plan, and delivers the upgraded application along with evidence-collection tooling for auditors.
Typical duration: 10–20 weeks depending on framework scope.
Event-driven refactor
An application built on synchronous request-response that has outgrown that pattern — long-running jobs blocking users, cross-service calls creating latency, data pipelines built as scheduled batch jobs. CORE identifies the flows that should be asynchronous, introduces event streams (Kafka, RabbitMQ, or cloud-native equivalents), and delivers the refactored system with proper retry and dead-letter handling.
Typical duration: 10–22 weeks depending on flow count.
Same workflow for every re-architecture
Regardless of which of the six patterns fits your project, the delivery workflow is identical. This is what makes Re-engineer predictable rather than an exploratory science project.
Business-logic extraction (never re-derivation)
CORE analyzes the existing codebase to catalog every business rule, every decision point, every calculation, every edge case. This becomes the reference specification — sacred, unchanged through the re-architecture.
Target architecture blueprint
Complete design of the new architecture — component boundaries, data flows, deployment topology, scaling strategy, failure modes. Reviewed and explicitly approved by your team before any code is generated.
Business-logic equivalence tests
An automated test suite that proves the new system produces the same outputs as the old system for every business scenario. This runs continuously through the build.
Incremental delivery with parallel-running
For long-running re-architectures, the new system runs in parallel with the old system, receiving the same inputs, and CORE's equivalence tests verify outputs match. Cut-over happens only when equivalence is proven at scale.
Rollback plan, always
Every re-engineering delivery includes documented rollback procedures. No architectural change is one-way.
When Re-engineer is not the right pathway
Re-engineer is powerful when the problem is architectural. It's the wrong tool when the actual problem is elsewhere. Being honest about this upfront saves everyone months.
Language migration only
If the target is just a new language or framework (with the same architecture), use Create's rewrite path instead.
Feature additions
If the goal is adding new features to the existing architecture, use Optimize.
Business-logic changes
Re-engineer preserves business logic exactly. If the logic itself needs to change, that's an Optimize job — or, for a wholesale rethink, a Create engagement.
Have architecture holding you back?
Book a call. We'll assess whether Re-engineer fits or point you to a better path.
Reference build coming soon
This pathway is fully operational — the discipline, review gates, and audit trail all shipped and in daily use across SSDB's own delivery work. Published reference builds for this specific pathway are being finalised as customer engagements close and can be shared under NDA.
Want to see this pathway live on your own problem? Bring us a scoped piece of work and we'll walk through the flow.
Founding pricing for Re-engineer runs $6,000–$58,500 per product — roughly a 30% uplift on a new build, because extracting business rules from undocumented legacy code is the real work.