Start with a defined next step
Request a legacy system review
Recover application behavior, data, dependencies and support risk before selecting a modernization path.
Page purpose
Know what you provide and what you receive when you request a legacy system review.
Choose a legacy system review when the decision centers on one application or a tightly coupled cluster and requires evidence about behavior, data, dependencies, supportability, and change risk before selecting a modernization option. This is narrower than the portfolio-oriented enterprise systems assessment.
Initial inputs: the system purpose, users, technology family, approximate age, support concern, known interfaces, and desired decision, all at a non-sensitive level. Immediate output: fit, clarifying questions, a proposed review boundary, and controlled-access requirements. If commissioned, outputs can include a behavior and dependency map, condition and risk baseline, option comparison, and recommended evidence-building step. Source, schemas, samples, logs, and access belong in an approved environment with minimum necessary permissions—not in the public form.
When to use this step
When is this the appropriate next step?
- Critical behavior is undocumented and understood by only a small number of people.
- Aging technology or unavailable expertise makes routine change increasingly risky.
- Replacement estimates are made without understanding data, interfaces, and edge cases.
What you receive
What you receive after fit is reviewed.
- Initial output: fit, scope, access assumptions, and review proposal.
- Commissioned output: behavior, data, interface, and operational dependency map.
- Commissioned output: condition and risk baseline with evidence confidence.
- Option comparison and recommended next slice or modernization path.
- Explicit exclusions, unknowns, and evidence that could not be obtained.
What happens next
What happens after the request is submitted.
- Frame the decision and define the system boundary.
- Recover behavior from users, code, data, documents, and observation as available.
- Map interfaces, jobs, infrastructure, support practices, and failure impact.
- Assess options against value, feasibility, continuity, data, and ownership.
- Recommend the smallest step that reduces the most material uncertainty.
What to prepare
Information that makes the conversation useful.
- Which application boundary and dependent processes are included.
- What controlled access can be provided and by whom.
- Whether the immediate need is stabilization, decision evidence, or delivery planning.
Information safety
Information that should not be sent through a public form.
- Exposing production credentials, data, source, or vulnerabilities through an unapproved channel.
- Assuming undocumented behavior is unused and can be removed.
- Recommending a rewrite before migration, coexistence, and acceptance complexity are known.
Decision questions
Know the boundaries of the next step.
What is enough for the initial legacy-system conversation?
Non-sensitive context about the system and the decision needed is enough. If source review is justified, access method, authorization, scope, retention, and working environment should be agreed first.
What should not be submitted through this page?
Do not submit source archives, credentials, database files, personal data, production logs containing sensitive content, exploit details, or confidential diagrams. Describe what is available at a high level.