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I will modernize your legacy mobile or web app, improve security and add ai
Senior Full Stack Engineer for Web Apps and AI Solutions
Senior Full-Stack Engineer with 5+ years of experience building secure, scalable web and mobile products for startups, healthcare, and enterprise teams. I work with Angular, React, Next.js, Ionic, Nod...
About this Gig
Is your existing app or web platform difficult to maintain, insecure, slow, or limited by outdated functionality?
I will assess and modernize your product while preserving the features your users rely on.
Services:
Upgrade outdated mobile apps and web applications
Update dependencies and fix breaking changes
Repair failed builds, plugins, APIs, and integrations
Improve authentication, permissions, validation, data handling, and API protection
Remove exposed secrets and insecure configurations
Improve performance, stability, and maintainability
Add AI chat, document search, summarization, automation, recommendations, or another agreed feature
Support testing, deployment, and app-store releases
You receive:
A clear assessment and agreed scope
Modernized, tested source code
A summary of security improvements
Progress updates and handover guidance
Every legacy system has different risks and complexity. Please message me before ordering so I can review the current version and goals and recommend the correct package.
Third-party subscriptions, usage fees, hosting, and store charges are not included.
FAQ
Which applications can you modernize?
I can work with existing mobile apps, web applications, SaaS products, dashboards, and API-backed systems. Message me with the current platform and version so I can confirm the scope.
Can you improve security without rebuilding the entire app?
Yes. I can harden agreed areas such as authentication, permissions, validation, API access, configuration, dependencies, and data handling. This is not a formal compliance certification or penetration test unless separately agreed.
What AI features can you add?
Examples include chat assistants, document search, summarization, classification, recommendations, content workflows, and process automation. The exact use case will be agreed before ordering.
Will you preserve existing features and design?
Yes. I prioritize keeping approved workflows and the existing user experience unless specific redesign or behavior changes are requested.
Do you need source code access?
Yes, read access to the current source code and setup documentation is normally required. Do not send passwords in the order form; we will arrange secure access if needed.
Can you help with deployment or app-store release?
Deployment or app-store release assistance can be included when agreed. Account fees, hosting, subscriptions, and third-party usage charges are separate.
Should I contact you before ordering?
Yes. Legacy projects vary significantly. A short review helps confirm risks, scope, package, and delivery time.
Reviews
5 reviews for this Gig
| (5) | ||
| (0) | ||
| (0) | ||
| (0) | ||
| (0) |
Rating Breakdown
- Seller communication level
- Recommend to a friend
- Service as described
Sort By
Most relevant
M mattdiving
Indonesia
Ongoing collaborationQuick, precise efficient. best developer.
$50-$100
Price
Helpful?V vinnybonfim
United States
Ongoing collaborationHe is the best, he's done 2 projects for me already, and was really fast and very communicative. I recommend his services anytime!
$100-$200
Price
Helpful?V vinnybonfim
United States
Ongoing collaborationAbhayjani was really helpful, was able to update my app from ionic 4 to v6, was really fast. Will def use his services again for other projects.
$200-$400
Price
Helpful?J jacastellanos91
Spain
Ongoing collaborationWonderfull experience, excellent job, and great communication
$100-$200
Price
Helpful?M mbdesignseo
Israel
Very good seller great job
$50-$100
Price
Helpful?
Reviews
5 reviews for this Gig
| (5) | ||
| (0) | ||
| (0) | ||
| (0) | ||
| (0) |
Rating Breakdown
- Seller communication level
- Recommend to a friend
- Service as described
Sort By
Most relevant
M mattdiving
Indonesia
Ongoing collaborationQuick, precise efficient. best developer.
$50-$100
Price
Helpful?V vinnybonfim
United States
Ongoing collaborationHe is the best, he's done 2 projects for me already, and was really fast and very communicative. I recommend his services anytime!
$100-$200
Price
Helpful?V vinnybonfim
United States
Ongoing collaborationAbhayjani was really helpful, was able to update my app from ionic 4 to v6, was really fast. Will def use his services again for other projects.
$200-$400
Price
Helpful?J jacastellanos91
Spain
Ongoing collaborationWonderfull experience, excellent job, and great communication
$100-$200
Price
Helpful?M mbdesignseo
Israel
Very good seller great job
$50-$100
Price
Helpful?
