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Services/Software Maintenance & Legacy Modernization
Service 08 · Software Maintenance & Legacy Modernization

Legacy systems, modernized in place, without the big-bang rewrite risk.

Refactoring, framework migrations, and gradual replatforming for systems too critical to break and too old to ignore — modernized in shippable increments, never a all-or-nothing rewrite. Trusted with long-lived business-critical systems across Nepal.

What the practice covers

Six capabilities, one accountable team

01

Legacy assessment

Codebase, dependencies, and institutional risk mapped before any migration plan is written.

02

Incremental refactoring

The strangler-fig pattern — new code paths introduced without a system-wide freeze.

03

Framework migration

Old frameworks and runtimes upgraded in stages, with tests as the safety net.

04

Database modernization

Schema and query modernization done without downtime on the production system.

05

Test-coverage backfill

Characterization tests written for undocumented legacy behavior before refactoring it.

06

Documentation recovery

Institutional knowledge captured in writing before the one person who knows it leaves.

How an engagement runs

Four phases, each with a named deliverable

Weeks 1–3

Assess

Codebase and risk map delivered, with a modernization plan sequenced by value.

Weeks 4–6

Stabilize

Test coverage backfilled around the riskiest, least-understood code paths.

Weeks 7–20

Migrate

Modernization delivered in shippable increments, never a system-wide freeze.

Ongoing

Sustain

The modernized system maintained under an ongoing support contract.

migration.log
# strangler migration · billing-servicelegacy_calls_routed = 12%new_service_calls   = 88%test_coverage_delta = +34%incidents_this_phase = 0status = "on schedule"
Migration phase complete — zero downtime
Why incremental, not a rewrite

Every change shipped, tested, and reversible

  • No big-bang cutover — traffic shifted gradually, with a rollback path at every stage.
  • Tests before touches — nothing gets refactored until its current behavior is characterized.
  • Documented as we go — the system is more understood after we leave than before we arrived.
The record

Built into every engagement

6
Capabilities covered in every engagement
3 wk
Time to a sequenced modernization plan
100%
Characterization tests before refactoring
0
Full-freeze, big-bang rewrites, by policy
Selected work

Modernization engagements on the record

2025

Regional utility provider — billing-system replatform

20-year-old COBOL billing core migrated to a modern service, zero missed billing cycles.

2025

Insurance carrier — monolith decomposition

Claims-processing monolith split into services over 9 months, no customer-facing downtime.

Common questions

Questions we get about legacy modernization

Why not just rewrite the system from scratch?

A big-bang rewrite freezes feature work and carries a high failure rate on systems too critical to break. The strangler-fig pattern introduces new code paths incrementally, so the system stays live and shippable the entire time.

How old a system can you realistically modernize?

Engagements have modernized systems over 15 years old, including COBOL-era billing platforms — age isn't the constraint, undocumented behavior and missing test coverage are, which is why stabilization comes before migration.

How do you avoid breaking undocumented behavior?

Characterization tests are written for the legacy code paths before anything is refactored, so current behavior is captured and verifiable — nothing gets touched until there's a test proving what it currently does.

Will there be downtime during migration?

Traffic shifts gradually in rehearsed waves with a rollback path at every stage — engagements have maintained uptime through the migration window rather than requiring a maintenance freeze.

What do we get besides the migrated code?

Documentation recovery is part of the engagement — institutional knowledge that previously lived in one person's head gets captured in writing as part of the modernization, not left behind.

Modernize without betting the system on a rewrite

A three-week assessment sequences the whole migration before you commit.

Start the assessment