Legacy applications usually have a bad reputation. But behind the seemingly old and dusty code is a legacy that is usually more valuable than initially assumed. What you really have in your inventory, you will realize when you want to get rid of legacy. But what makes an application a legacy application? eXplain and our consultancy services are your key to get the truth perspective! Step into and learn about!

1. eXplain
The tool for code
analysis and software
reengineering.

2. ■ Grown mainframe software at
a glance
 Complex
 Functionally overloaded
 Technologically outdated

3. ■ Individual software: from
competitive advantage to
sore point
Challenges:
 Undocumented, historically grown
architectures
 Costs are increasing due to a lack of
integration, networking and automation
 Unstoppable „bleeding“ of the expert
teams (attraction of young talents fails)
 New business processes can barely be
mapped
 Threat to the company‘s ability to act.

4. How do I analyze and
clean up the source
code, thereby relieving
its transformation and
contributing to ESG
goals?
How do you manage
to win new employees
for the current
environment and train
them efficiently and
quickly?
How do I recognize in
time that I have to
intervene before it‘s
too late and that the
quality and
maintainability of the
system are at
enormous risk?
■ The urgent questions are:
Without… the existence of written system documentation, the need for expensive external resources or an
extreme expenditure of time from experienced colleagues?​

5. ■ The answers to these
questions are provided by
 Understand source code monoliths
 Speed up training
 Avoid programming errors
 Increase quality of code

6. individual
info
code
analysis
clustering
software
quality
■ eXplain at a glance.
parser incl.
preprocessor
sources
Defined interface for
additional info (APIs)
Repository
(IBM Db2 or
PostgreSQL)
JDBC
job-network
visualization
eXplain Server
SQL access

7. ■ Which sources are supported by eXplain?
Programming
languages
 Cobol
 PL/I
 Assembler
 Natural
 RPG (IBM i)
 JCL
 CL (IBM i)
 REXX (teilweise)
 Cobol generators
(Telon, Detab
Cobol, ….)
Databases
 Db2
 Adabas
 IMS-DB
Scheduler
 AJM
 TWS
 Control-M
Transaction monitors
 CICS
 IMS-DC
What are we not
doing?
 Java
 desired and
wanted expandability
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8. ■ Individual infos & APIs with
which eXplain achieves
more for you
Information (in csv format) for enriching the
parsing:
 transactions
 Menu structures from the database
 MQ information
 Variable tables (for scheduler)
The following are fed into the repository via API:
 Runtime information (object statistics on IBM i)
 Deployment information
 Execution statistics (SMF Records on z/OS)
 HTML documentation links

9. ■ What is special about the
PKS parsers:
eXplain works like a kind of preprocessor
that also resolves complex constructs:
 Dynamic calls (e.g. CALL <variable>, if
the information is within the source code)
 Macros (PL/I, ASM)
 Included structures (COPY, INCLUDE)
If information about dynamic calls comes
from a database, it must be added to the
parsing manually ("individual information").

10. ■ Code analysis with eXplain
Sourcecode-Screening
 Overview diagrams of all dependencies
and connections
 Display of redundancies and
inconsistencies
 Code cleanups
 Technical re-documentation of the code
Parser and documentation are individually
adaptable to special customer situations

11.  Faster impact analysis in the event of
changes or errors thanks to graphical
representation of
dependencies/interrelationships instead
of manually tracing the call chain (e.g.
code or Xinfo)
 Overall picture of the application
landscape on the MF
 Easy detection of dead code, plannable
ESG actions
 Faster training of new employees
through live graphical representation of
the application landscape
■ Code analysis
UseCase/customer added value:

12. ■ Source explorer
- All sources are loaded into the repository
- Complex searches are also possible if
there is only a client plugin or no sources in
general in the workspace
- Linking queries at source code level with
repository information
- Search in ranges or with regular
expressions

13. In mainframe development it is unusual to
keep the sources in the IDE workspace
(e.g. IDz, Eclipse...) permanently. By storing
the sources in the eXplain Repository:
 Complex searches and queries can still
be performed on all sources
 Saves MIPS by querying with XINFO
and self-developed searches
Since the eXplain repository can be
enriched with customer-specific information,
searches and queries can be linked to this
information.
■ Source Explorer
UseCase/customer added value:

14. ■ Reporting / evaluations
- Multiple queries (UMQ)
- New depiction
- Unified layout
- Grouping
- Advanced scripting
- User report
- Possibility to embed external HTML
links
- Nested SQL loops

15. In addition to the reports provided by
eXplain, your specific evaluations can be
embedded to e.g.
 Automatically generate audit compliant
change reports
 Specific reports for different target
groups, e.g. Operations, Dev, Mgmt
 Reports for projects on interfaces of
applications, files and databases that
will be affected by changes, e.g. for
more targeted effort estimates
■ Reporting / Evaluations
UseCase/customer added value:

16. ■ eXplain visualizes your source code

17. ■ Clustering with eXplain
Structure of the source code in functional
entities
Basis for:
 Module-related migration planning
 Flawless communication in the project team
 Delimitation of non-migration-relevant
modules
Complex and opaque software systems can be
systematically structured. Interfaces between
application systems can be identified without
errors and a clear structure of architecture can
be achieved.

18. Clustering allows modules to be grouped
into logical/subject entities that correspond
to your specific organization, e.g. Product -
> Components -> Modules.
 Using the graphical representation,
interfaces and responsibilities can be
quickly identified as well as a more
precise identification of the impact of
planned source code changes.
■ Clustering
UseCase/customer added value:

19. 1
2
3
■ Cleanup and clustering are the
basis for successful migration
planning and implementation.
1. Initial situation:
Uncleaned system
2. Cleaned system
after initial cleanup:
 Avoid errors
 Develop faster
 Make better decisions
3. Clustered application:
 Clear processes
 Clear communication
 Error-free implementation

20. ■ The clustering with eXplain makes functional entities and their
technical interdependence transparent.

21. ■ Clustering
- Visualization option „Sankey“ diagrams
- Differentiated representation of IO
interfaces

22. ■ Quality control with eXplain
Maturity assessment of legacy
applications based on general or
customer-specific parameters
 Management and project leads can
monitor the progress of cleansing or
further development
 Fault prevention by proactively
identifying potential sources of error in
the code
Quality assurance for working with
freelancers or nearshore/offshore teams

23. Using the key figures from the Quality
Dashboard, you can:
 Quickly identify areas for action, e.g. to
reduce complexity and increase
maintainability.
 Monitor the source code maintainability
of changed/new code from internal and
external developers in a measurable
way.
 KPIs can be included in contracts with
external service providers
■ Quality control with eXplain
UseCase/customer added value:

24. ■ The QA dashboard supports project leads and quality
managers in checking progress

25.  Adaptation and individualization to the
environment of the customer
 Basis for this is that PKS holds the
full development rights with eXplain
 On the one hand, PKS is constantly
developing the parser and, on the
other hand, can customize the
visualization
 New features can be developed, tested
and made available independently of
release cycles.
 This is an unbeatable advantage,
especially in PoC and time-critical
analysis phases
■ eXplain can be adapted to the
customer‘s individual setup

26. „With eXplain from PKS, we were able to identify a fair amount of code
that was no longer needed in our Natural- and Cobol-based core banking
system and thus basically clean up and streamline the system. The
documentation created completely automatically by eXplain also fully
meets our revision requirements. These are just two examples of how
eXplain supports us in our core banking system stabilization project.
However, I would also like to particularly emphasize the extremely
pleasant cooperation with the competent PKS team and the flexible
possibilities in everyday project work, so that we were able to take
Helaba-specific requirements into account at all times.
Stephan Böcher
Gruppenleiter Anwendungsentwicklung
Helaba-Landesbank Hessen-Thüringen
■ Reference quote

27. Goals and benefits:
 All required result types were delivered with 100% coverage.
 eXplain provides recommendations for the maintenance and
stabilization of ZDV.
 The automatically generated data processing concepts serve as
audit-proof documentation for the Bafin
Realization:
 Phase 1: Proof-of-Concept for KUN, KUN-DIA und KSA
(934 modules with 729.586 lines of code)
Duration: 01.09.18 - 22.01.19
 Phase 2: Complete implementation for the core banking system
(11.815 program modules with 2.322.250 lines of code)
Duration: 15.03. – 30.09.2019
 Phase 3: Implementation for all mainframe applications
Duration: since Q1 2020
 Phase 4: Complexity reduction to progressively modernize and
replace
Background info:
 Helaba plans to replace its core banking
systems with SAP or something similar in the
long term, but has stopped the first attempt at
implementation due to underestimated
complexity and Bafin reprimands.
 Now the AWS must be separated, technical
modules must be assigned, interfaces must
be shown and everything has to be
documented automatically
 Our technology and our competence
convinced in the RfP compared to the
competition because:
 Our base technology for procedural
languages is better
 Our parsers for all necessary languages
are very mature
 The eXplain clustering is unique
 Our repository is complete, but still clear
 We offer a powerful visualization and
documentation option
■ Reference project

28. The advantages for your
company by using
eXplain and working
together with PKS.

29. … and reduce up to
42% of your mainframe
code.
■ 1st advantage:
You rely on the best analysis
technology on the market.

30. LzLabs ADDI Sonar
Qube
CAST Micro-
focus
eXplain
Scope of functions /
technology coverage
Neutrality in relation to the
migration variant
On-site support by German-
speaking consultants
Full Visualization /
Ease of use
Dynamic call support,
preprocessor
■ Market Classification of Legacy Analysis Tools
Legend:
Fully
covered
Partially
covered
Barely
covered
Not
covered

31. … 100% flawless
communication.
■ 2nd advantage:
You benefit from the
combination of the technical
and professional view of your
applications.

32. ■ 3rd advantage:
PKS has the manpower, the
know-how and the flexibility
that you need for the
success of your project.

33. ■ You find new employees more
easily – and they become
productive twice as fast.

34. ■ You identify and eliminate
code that is no longer
needed.

35. ■ You avoid misunderstandings
between the specialist field and
the development.

36. ■ You document
reality – repeatable
at any time.

37. You want to learn more?
Then download the new whitepaper!
https://www.pks.de/de/explain-whitepaper
■ eXplain Whitepaper

38. You reduce
costs
You eliminate
risks
You find new
employees more
easily
You use
innovative
technology
■ Your benefits at a glance

39. Heidi Schmidt
Managing Director (CEO)
+49 (0) 751 56140 229
heidi.schmidt@pks.de

40. Bernd Butscher
Head of Enterprise Software Transformation
+49 (0) 751 56140 257
bernd.butscher@pks.de