Modernize legacy systems 2× faster.

AI-assisted analysis and refactoring. Move to cloud without the risk. Shorter timelines. Lower cost. We keep your systems running while modernizing underneath, your business keeps going, your architecture improves.

The challenge

Legacy code is a prison.

Monolith. No separation of concerns. Dependencies everywhere. Nobody wants to touch it because touching it breaks something. But your new AI features can't run on legacy architecture, and every quarter you wait, the gap to your AI-native competitors widens. You're stuck. Migrating is risky. One mistake and you're down. Doing nothing is riskier.

Maintenance tax. 60–80% of IT budget bleeds into keeping the monolith alive. Every dollar there is a dollar not spent on the AI roadmap.
Talent flight. Engineers don't want to maintain code older than they are. Your best people leave. The ones who stay don't know the new stack.
Compliance drag. Legacy stacks rarely have the audit trails AI Verify, NIST, and PDPA expect. Every regulator visit becomes a fire drill.
AI ceiling. RAG, agents, and event-driven workflows assume modern primitives. A 15-year-old monolith can't host them. Your AI program stalls before it ships.
The EIS approach

Safe, incremental modernization, never a big-bang migration.

We don't ask you to bet the company on a switchover weekend. We migrate one service at a time, run old and new in parallel, and shift traffic gradually. AI accelerates the analysis and refactoring. Humans make the decisions. You see results in months, not years, without an outage to explain to the board.

The Framework

Five steps from monolith to modern.

Each step has its own deliverable. Each step is reversible. You stay in control of pace, and you can pause between any two phases if priorities shift.

PHASE 01

ANALYZE

AI code-analysis tools map your system's true structure, every dependency, every dead path, every implicit contract that nobody documented. We discover what your codebase actually does, not what the wiki says it does.

Deliverable
System map · dependency graph · risk register
PHASE 02

PLAN

We sequence the migration around business risk, the boring services move first, the load-bearing ones move with the most preparation. One service at a time, in the order that compounds.

Deliverable
Migration roadmap · service slicing plan · rollback strategy
PHASE 03

REFACTOR

AI suggests refactorings at scale, extract this module, split this class, replace this dependency. Humans verify every meaningful change. The AI is a draft, the engineer is the editor, the reviewer owns the merge.

Deliverable
Refactored services · automated test suite · code-review evidence
PHASE 04

PARALLEL RUN

Old and new systems run side by side. Traffic shifts gradually, 1%, 10%, 50%, 100%, with shadow comparisons at each step. If anything diverges, we roll back instantly. Users notice nothing.

Deliverable
Live shadow-traffic dashboard · zero-downtime cutover plan
PHASE 05

DECOMMISSION

Once every consumer is on the new system and the metrics are clean, the legacy stack is retired. The savings, infrastructure, license, maintenance hours, flow back to the AI program that started this in the first place.

Deliverable
Retirement plan · cost recovery report · post-mortem
Where we work

Four shapes of modernization. We've shipped them all.

Most engagements are a blend, a monolith moving to microservices on its way to the cloud, or an on-prem ERP getting wrapped in event-driven APIs. We start with whichever transition unblocks your AI roadmap fastest.

01 / FEATURE

Monolith → Microservices

Strangle the monolith one bounded context at a time. Each new service ships with its own data, its own deploy pipeline, and its own SLO.

02 / FEATURE

On-prem → Cloud

Lift, reshape, and land, not a naive lift-and-shift. We re-platform what benefits from cloud primitives and leave the rest where it belongs.

03 / FEATURE

Proprietary → Open-source stack

Escape vendor lock-in on databases, queues, and middleware. Our AI tooling rewrites the integration layer; humans validate behaviour against the legacy contract.

04 / FEATURE

Synchronous → Event-driven

Replace brittle request/response chains with events and queues. Your systems decouple, your AI agents finally have a substrate they can subscribe to.

Where AI accelerates. Where humans decide.

We draw the line on day one. AI is leverage on the routine work, humans own every decision that touches risk, data, or downtime.

Status Quo

AI accelerates

  • Static analysis of millions of lines of code
  • Mapping dependencies and call graphs
  • Generating refactoring suggestions
  • Drafting unit and integration tests
  • Translating between languages and frameworks
  • Producing migration runbooks and docs
The EIS Way

Humans decide

  • Service boundaries and bounded contexts
  • Data migration and reconciliation strategy
  • Cutover sequencing and rollback triggers
  • Security and governance trade-offs
  • Acceptance criteria for parallel-run divergence
  • Final merge approval on every change

We thought it would take two years and a feature freeze. EIS shipped the first new service in eight weeks, parallel-ran the whole way, and we never had a customer-visible outage. The AI roadmap unblocked itself.

CTO · ASEAN financial services · 12-month modernization

What changed for one financial-services client.

15-year-old monolith decomposed into 22 microservices
Timeline: 12 months delivered vs. 24 months estimated
Zero customer-visible downtime, parallel-run for the entire migration
Total cost: ~30% under the original estimate
Maintenance burden: 65% of platform team time → 20%
First production AI feature shipped in month 6, on the new architecture
FAQ

Frequently asked

What IT leaders ask before they commit, and what we answer.

Q01Will the migration cause downtime?
Our default is zero customer-visible downtime. Parallel-run with shadow traffic is the standard pattern, not a premium add-on. If a service genuinely cannot run in parallel, we say so up front and design a maintenance window with you, never around you.
Q02How do you handle data migration without losing or corrupting records?
Dual-write, then reconcile, then cut over. The new system writes alongside the old until reconciliation is clean for a sustained period. We don't flip the switch until the diff is zero, and we keep the rollback path warm for weeks after.
Q03Can we pause if business priorities change?
Yes. The phased structure is designed for it. After any phase, you can hold position with both systems running. We'll document the seam so you can resume in three months or three quarters without losing context.
Q04Won't AI-generated refactorings introduce bugs?
Every AI suggestion is reviewed by a human engineer before merge, and every refactor ships with regression tests against the legacy contract. The AI accelerates the work; the test suite and reviewer catch what the AI gets wrong.
Q05How do you keep the lights on while we modernize?
Our team works alongside your platform team, not instead of it. Critical legacy fixes still ship on the old stack while the new one is being built. Modernization runs in parallel to operations, never on top of them.
Q06What if we discover the legacy system does more than we thought?
Common, and exactly why ANALYZE comes first. The dependency graph surfaces the surprises before they hit the migration plan. If new scope appears, we re-sequence; we don't ignore it.
Q07How do you measure success?
Three numbers, tracked monthly: services migrated, infrastructure cost recovered, and platform-team hours freed. Everything else, velocity, reliability, AI-readiness, is downstream of those three.

Stuck behind a monolith?

Schedule a 30-minute modernization assessment. We'll map your highest-risk dependencies, the fastest path to cloud, and where AI fits in the refactor, for your stack.

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