Fictional example

Example: Legacy Check of a .NET 4.8 application

What do you get for €2,499 net? This example shows a complete Legacy Check – from the initial situation and the traffic-light rating to the recommendation with a roadmap. You can download both parts of the report as PDFs.

Download the report Request a Legacy Check

The situation

Muster Metallbau GmbH (fictional) – Mid-sized metalworking company with 140 employees at two sites.

Central order processing: quotes, orders, costing, production orders, delivery notes, label printing, invoice preparation and DATEV export (German accounting software).

AuftragsPro was developed in-house from 2009 and has been the backbone of order processing ever since. The main developer retired in 2024; since then an external freelancer has looked after the application occasionally. Management wanted to know how big the risks are and which path makes economic sense: keep running, modernise or replace.

  • Assess risks for operations and IT security
  • Secure knowledge of business logic and technology
  • Find an economical path for the next 5–10 years

Scope of the Legacy Check
Fixed price €2,499 net · Completed within 2 calendar weeks

  • Analysis of the complete source code and database schema (anonymised copy, no live data)
  • AI-assisted code analysis with the right model for each task and proven prompts, all findings reviewed by experienced developers
  • Two interviews: business department (order processing) and IT
  • Review of infrastructure, operations, third-party components and licences
  • Results presentation (online, 60 minutes) and this report

The result

Valuable for the business, technically at acute risk

AuftragsPro reflects Muster Metallbau GmbH's processes very well – the special costing in particular is a real competitive advantage. Technically, however, action is urgently needed: the database platform no longer receives security updates, database access uses administrator rights, and knowledge of the application largely left with the former developer. A complete rewrite is not necessary: the business logic can be preserved and technically modernised.

Traffic-light rating

  • RedIT securityDatabase server without security updates; access via the sa account with a plain-text password; 312 places with concatenated SQL.
  • RedOperations & infrastructureUnsupported server platform; restore from backup never tested; build only reproducible on one notebook.
  • RedKnowledge & documentationMain developer retired; documentation from 2011; only approx. 20 of an estimated 140 business rules documented.
  • AmberMaintainability & code qualityAbout 60% of business logic in forms; 14% duplicated code; Option Strict off in 6 of 9 projects; no tests.
  • AmberTechnology outlook.NET Framework 4.8 is maintained but no longer developed; VB.NET gets no new language features; third-party components outdated.
  • AmberDatabase & dataSound data model, but 40% of relations without foreign keys and approx. 6% duplicate customer records.
  • GreenBusiness fitCovers the processes very well; high user acceptance; special costing as a competitive advantage.

The five biggest risks

No.RiskRatingAction
R1Database server without security updatesSQL Server 2012 (end of support 07/2022) and Windows Server 2012 R2 (end of support 10/2023) no longer receive security updates.CriticalMigrate to SQL Server 2022 and Windows Server 2025.
R2Database access with administrator rightsAll 45 clients connect with the sa account; the password is stored in plain text in the configuration file.CriticalDedicated service account with minimal rights, remove the password from the configuration.
R3Knowledge monopolyBusiness rules are spread across form code and stored procedures and are barely documented.HighDocument core processes and business rules (arc42), hand knowledge over to the team.
R4Build not reproducibleThe application can only be built on a single developer notebook with Visual Studio 2015.HighMove to Git, automated build pipeline.
R5Backup untestedThe nightly backup has never been restored; there is no emergency procedure.HighRestore test, documented emergency procedure.

The options compared

OptionEffort without AIDuration without AISaving with AIAssessment
AStabilise and keep runningImmediate security measures, platform update, secure build and backup; the code stays unchanged.35–45 PD2–3 months20–30%Essential as an immediate step, not sufficient alone
BModernise the technologyrecommendedMigration to .NET 10 (LTS), AI-assisted conversion from VB.NET to C#, tests for core processes, renewed reports and third-party components; business logic and user interface stay the same.430–570 PD15–20 months60–80%Recommended (after option A)
CStep-by-step replacement with a web applicationNew browser-based application, module by module using the strangler fig pattern; parallel operation with AuftragsPro.620–800 PD24–36 months50–60%Sensible perspective for parts, not as a whole
DIntroduce standard software (ERP)Replacement by an industry-standard ERP system with customisation.high (plus licences)11–19 monthsapprox. 20%Not recommended

Effort and duration estimated without AI. Our AI-assisted development reduces time and cost by the range shown; the roadmap already includes AI.

Recommendation and roadmap

We recommend first removing the critical risks (option A) and then modernising AuftragsPro technically (option B). This preserves the valuable business logic and puts the application back on a secure, supported foundation. A web interface for field sales can then be added step by step (part of option C).

  1. Phase 1

    Immediate measures

    Months 1–2 · 25–35 PD

    Migrate the database server, service account instead of sa, restore test, Git and build pipeline

  2. Phase 2

    Modernisation

    Months 3–9 · 130–170 PD

    .NET 10 and C#, tests for core processes, migrate 38 reports, renew third-party components, documentation

  3. Phase 3

    Field sales web module (optional)

    From month 10 · 60–80 PD

    Quotes and order status in the browser, step by step

Phases 1 and 2 combined: 155–205 PD with AI-assisted implementation – without AI it would be approx. 465–615 PD. Estimate accuracy ±25%.

Download the report

The report has two parts: a compact summary for management and a detailed analysis for IT. Click a page to enlarge it.

Part 1: Management summary

PDF · 4 pages · 409 KB

Download PDF
  • Part 1: Management summary, Page 1
  • Part 1: Management summary, Page 2
  • Part 1: Management summary, Page 3
  • Part 1: Management summary, Page 4

Part 2: Detailed analysis

PDF · 10 pages · 643 KB

Download PDF
  • Part 2: Detailed analysis, Page 1
  • Part 2: Detailed analysis, Page 3
  • Part 2: Detailed analysis, Page 4
  • Part 2: Detailed analysis, Page 7
  • Part 2: Detailed analysis, Page 9
  • Part 2: Detailed analysis, Page 10

More example reports

Every application is different – and so is the right path. These fictional examples show the Legacy Check for other technologies.

  • Delphi 7 · Firebird

    Delphi inventory system at a wholesaler

    Delphi 7 and Firebird: e-invoicing obligation, knowledge monopoly and step-by-step replacement with a web application.

  • IBM i · RPG · COBOL · Db2

    IBM i application in logistics

    RPG, COBOL and Db2: staffing risk, missing interfaces – add APIs first, then replace modules step by step.

Your own Legacy Check

Fixed price €2,499 net, results usually within two weeks – with a report, a results presentation and a concrete recommendation for your application.

Request a Legacy Check