Arguments in favor of a progressive software rewrite . Blog post here : https://sylvainleroy.com/2018/06/18/to-rewrite-or-not-to-rewrite-a-software/ It's a presentation about why software should be preserved and . Written and adapted for Byoskill. Byoskill.com

1. Arguments in favor
of a progressive
rewrite
Automatic legacy software migration
https://www.byoskill.com

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Why are we there ?

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We are healers
for
unlucky software

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Because
the market goes fast
And software, the victim

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❖ Software ages
❖ Software becomes irrelevant
❖ Software may have broken concepts
❖ Software without love :-(
❖ Fashion is gone
We help a lot of software

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Our unique
skills
● Source to source refactoring
● Static code analysis
● Code (re) generation

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Our tools
Transform the code and
the architecture automatically
➔ Speed up the upgrade of a software
➔ Replacing outdated technologies

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Your gain
➔ Increase the success-rate of
rewrite projects
➔ Shorten the “out of order” effect
➔ Decrease the cost and risk of
migration

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Our Patient
Your software XX

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A great Software
that becomes old

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A common (current) wish :
Transform a monolith application
Into a SaaS/Cloud based solution

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Your software
has
an amazing set
of
functionalities

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Why a progressive rewrite is possible
1. The team loves its product
2. But would like :
a. To feel more confident when a LOC is about to be changed
b. To provide more efficiently new exciting features
c. To live a better technology experience
d. To solve the main architectural problems

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What we want
➔ Robustness
➔ Simplicity
➔ Softness
➔ Productivity
Katrina Asfardi

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What we have
➔ Fragility
➔ Complexity
➔ Rigidity

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What the doctor’s tool says

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What the mama says
An architecture solution
that missed the goal

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Daily routine
● Instability / Fiability problems
○ Productivity problems (never the developer fault!)
○ Technology mess, requires godlike developers
○ Application: IDE Hostile
● Testable problems
○ Tough debugging
○ Not designed for unit tests
○ Not-so-obvious installation and deployment procedure
● Non-standard way of development and technologies
○ Costly to evolve
○ Tightly coupled to the technologies

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What are the evolutions ?

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“Cities grow, cities evolve, cities have parts that simply die while others parts flourish ;
each city has to be renewed in order to meet the needs of its populace…
Software-intensive systems are like that…”
- Grady Booch

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TOP 5 Reasons
… to not attempt a big rewrite
1. It's a critical product for XYZ
2. Its featured-rich content is hard to reproduce
3. It will take longer than you think
a. markets change
b. existing customers may become frustrated
4. XYZ is an experienced software
a. many bugs have been found
b. many bugs have been fixed
c. use has been customized for the customer satisfaction
5. A complete frustration for the team during the whole rewrite

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Our suggestion:
● An incremental (smart) approach
● Refactor and improve the existing base in a
big (automated) jump
● Obtain a functional architecture quickly

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A possible Roadmap
Fix the main
issue
Create
functional
modules
Upgrade the
technologies
Create your
Cloud/SaaS
system
Improve the software factory process

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The tasks
1. Fix the main issue
2. Creation of a functional architecture
a. Functional modules
b. Loosely coupled
3. Externalization of the functionalities shared with other products
4. Technology change for Open-source/Standards
5. Improves the software release process to make it
a. less difficult
b. more DevOps friendly

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Our solution

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Our offer
An IDE Tool
To fix the issue with Automation
Time optimization: min 60%
Cost reduction: >50%

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Better make it
fast and safe
And a whole new road begins right
there...