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Asad S.

5.0

200

8.4

96%

Islamabad, Pakistan

$20 USD per hour

Please visit my full portfolio: https://divulgetechnologies.com/ I am a Full-Stack, AI, and Digital Solutions Engineer with 15+ years of experience delivering websites, business apps, automation systems, API integrations, CRM workflows, dashboards, digital marketing support, presentations, and technical problem-solving. I help clients turn ideas into practical deliverables, from planning and design to development, deployment, optimization, documentation, and post-launch support. 30-Day Guarantee with Full Support Coverage After Project Completion. Core Expertise: - Custom websites, web apps, dashboards, portals, SaaS tools, admin panels, and business software - PHP, MySQL, JavaScript, React, Node.js basics, Python, Flask/FastAPI, MERN, LAMP, and CakePHP - WordPress, WooCommerce, Shopify, Magento, OpenCart, PrestaShop, CS-Cart, WHMCS, Webflow, Wix, Squarespace, Framer, Base44, Lovable, and Odoo - Flutter mobile apps for Android and iOS - REST APIs, webhooks, payment gateways, data sync, and third-party integrations - AI / ChatGPT integrations, AI assistants, automation tools, Python MVPs, and AI-enabled workflows - CRM, lead capture, verified lead workflows, appointment-setting systems, GoHighLevel, Zoho CRM, forms, funnels, and marketing automation - Landing pages, analytics, conversion tracking, email/SMS/WhatsApp workflows, and lead management - UI/UX, responsive web design, Figma-to-web, product pages, checkout pages, and conversion-focused layouts - PowerPoint, pitch decks, executive presentations, educational presentations, visual storytelling, infographics, and editable business documents - Canva, Figma, Adobe-style assets, social/web graphics, product visuals, storyboards, and AI-assisted image/video concepts - Three.js, WebGL, Unity-style interactive experiences, product visualization, and marketing animation support - SQL databases, reports, authentication, booking systems, inventory tools, and operational dashboards - Hosting, cPanel/WHM, VPS, Cloudflare, SSL, DNS, Linux/Windows Server, deployment, migration, speed optimization, and troubleshooting - Business process, logistics, capacity-planning, simulation-style workflows, AnyLogic/FlexSim-style support, Excel/SQL data preparation, scenario reporting, and documentation Many projects are not only websites. They involve connecting software, data, marketing, operations, reports, presentations, APIs, cloud services, and business workflows. I help turn those moving parts into dependable deliverables. What You Can Expect: - Clear communication - Practical technical advice - Clean, scalable implementation - Business-focused problem solving - Reliable troubleshooting - Proper documentation - 1-month free support after delivery Whether you need a website, eCommerce store, app, API integration, automation workflow, CRM setup, lead generation system, dashboard, presentation deck, AI tool, server fix, creative web asset, or business process solution, I can help you build it properly.

DOS PHP ASP Java JavaScript

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Shahid R.

4.9

123

8.3

100%

Sialkot, Pakistan

$45 USD per hour

Time Designs providing timeless designs around the globe helping companies with all their graphic design needs from a decade. We offers superior services for following :- - Creative logo design - Corporate identity - Business cards - Letterhead - Envelopes - PowerPoint Template - Flyers - Brochure - Website Designing - Invoices - Label Design - All kinds of official stationery items. 100% positive feedback from customers. Guaranteed services.

DOS Website Design Graphic Design Banner Design Logo Design

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Mashal K.

5.0

3.5

100%

Islamabad, Pakistan

$20 USD per hour

Hi! I'm Mashal Khan, a Microsoft Cloud Solutions Architect with over a decade of experience in designing, implementing, and automating IT infrastructure. I specialize in Microsoft 365, Azure, Windows Server technologies, and advanced scripting with PowerShell. My background in Computer Science, combined with a deep passion for technology and problem-solving, enables me to deliver robust and scalable solutions for businesses of all sizes. Whether you're looking to automate cloud deployments, streamline IT operations, migrate workloads, or set up secure hybrid environments, I bring hands-on expertise and a practical approach. I'm highly skilled in cloud infrastructure, networking, automation, and security — with a strong emphasis on reliability, performance, and cost optimization. Key Skills & Services: Microsoft Azure (VMs, Networking, Automation, IAM, ARM) Microsoft 365 (Exchange Online, SharePoint, OneDrive, Teams) PowerShell & Scripting Automation Azure AD & Identity Management Server Administration (Windows Server, AD DS, DNS, DHCP) Infrastructure Design & Architecture Network Setup & Troubleshooting SharePoint Online Migration & Management Freelance Consulting & Technical Support I'm committed to delivering high-quality work, clear communication, and long-term value to my clients. Let’s collaborate and take your cloud and IT projects to the next level.

DOS Windows Desktop System Admin Linux Customer Support

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Muhammad Shazad F.

5.0

2.2

100%

KARACHI, Pakistan

$25 USD per hour

## BIO Name: Mohammad Shazad Fakhir Date of Birth: 12 December Area Of Birth : Karachi ,Pakistan I am an IT Consultant with Sixteen Years of Experience in many prestigious IT companies. I have expertise in designing and developing both Desktop and Web Applications from scratch using traditional and latest Platforms. Also provide technical consultancy (included integrations, Report development, customization, personalization) to popular Business Application like Oracle EBS Suite. ERPNext, Oracle Fusion Cloud and many others. A part of development, I also provide Digital Marketing services specially in Search Engine Optimization, Social Media Marketing. Search Engine Marketing. ## Area of Expertise My areas of Expertise are: VB6 (5+ Years). ASP (5+ Years). ASP.net (5+ Years). .net(C#, VB) (5+ Years). PHP (7+ Years). ER/Studio (5+ Years). SQL Server (12+ Years). Oracle EBS ERP (4+ Years). Oracle Report Builder (6+ Years). Oracle PL/SQL (6+ Years). OBIEE (1+ Years) ERPNext (1+ Years). MySQL (5+ Years) WordPress (2+ Years) Digital Marketing (2+ Years) E-Commerce Store (5+ Years)

DOS PHP ASP JavaScript Visual Basic

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How to hire a great freelance DOS Developer

A DOS developer builds, maintains, and modernizes software that runs on MS-DOS, FreeDOS, PC DOS, and DOS-compatible environments, including legacy business applications, embedded industrial systems, and retro computing projects. These specialists work with low-level languages and toolchains that most modern programmers no longer touch, which is exactly why hiring one requires deliberate evaluation.

What a DOS developer actually does

DOS development covers a narrow but commercially important slice of software engineering. Many manufacturing plants, point-of-sale terminals, accounting systems, scientific instruments, and government databases still run on DOS because the software is stable, the hardware works, and rewriting it would be expensive. A skilled DOS programmer keeps these systems alive, ports them to modern environments, or recreates DOS-era experiences for emulation, gaming, and education.

Typical engagements include patching legacy executables, recompiling source from older compilers, writing new utilities in C or assembly, building TSR (terminate-and-stay-resident) programs, debugging memory issues in conventional, EMS, or XMS memory, and packaging software to run on DOSBox, DOSBox-X, or vDos for modern Windows machines.

Common deliverables and services

Maintenance and bug fixes for existing DOS business applications written in Clipper, dBase, FoxPro, Turbo Pascal, or Turbo C

Porting DOS software to Windows, Linux, or web-based front ends while preserving business logic

New tool development in x86 assembly (NASM, MASM, TASM) or C using Open Watcom, Borland C, or DJGPP

BIOS-level and hardware interrupt programming for embedded boards and industrial controllers

Retro game development, demoscene productions, and homebrew titles for VGA, EGA, and Sound Blaster targets

DOSBox configuration, packaging, and distribution for commercial re-releases of legacy software

FreeDOS image creation, bootable USB builds, and BIOS flashing utilities

File format reverse engineering and data extraction from proprietary DOS databases

Tools, languages, and frameworks

Genuine DOS work relies on a specific stack that buyers should look for in a candidate's portfolio. Expect to see fluency with several of the following.

Languages: x86 assembly, C, C++, Turbo Pascal, Clipper, dBase, FoxPro, QuickBASIC

Compilers and toolchains: Open Watcom, Borland Turbo C/C++, DJGPP, Microsoft C, NASM, MASM, TASM

Emulators and runtimes: DOSBox, DOSBox-X, DOSBox Staging, vDos, PCem, 86Box, FreeDOS

Debuggers and utilities: Turbo Debugger, CodeView, SoftICE-era tooling, IDA for reverse engineering

Memory managers and APIs: EMM386, HIMEM, DPMI, Int 21h services, BIOS interrupts

Sound and graphics: Sound Blaster programming, AdLib, VGA mode 13h, mode X, VESA BIOS Extensions

Industries and use cases that still need DOS

The demand for DOS expertise is more common than most clients expect. Typical hiring scenarios include:

Manufacturing and industrial automation, where CNC machines and PLCs run DOS-based control software

Retail and hospitality businesses still operating legacy POS and inventory systems

Accounting, payroll, and ERP systems built in Clipper or FoxPro that need migration or maintenance

Medical devices, scientific instruments, and laboratory equipment with embedded DOS firmware

Government and archival projects requiring data recovery from old proprietary file formats

Game studios and publishers re-releasing classic titles on modern storefronts via DOSBox

Education, hobbyist, and demoscene communities producing new software for vintage hardware

How to evaluate a DOS developer

Because the field is small, portfolio depth matters more than years of generic experience. Look for candidates who can show working DOS code on GitHub, contributions to FreeDOS or related open-source projects, demoscene productions, or documented commercial maintenance work. Strong candidates will also understand the constraints of real-mode and protected-mode programming, segmented memory models, and the differences between conventional, upper, expanded, and extended memory.

Useful interview questions to copy and use:

Which compilers and assemblers have you used for DOS targets, and what made you choose one over another for a given project?

Can you walk me through how you would debug a TSR that conflicts with another resident program?

How would you approach porting a Clipper or FoxPro accounting application to a modern platform without losing business logic?

What is your experience with DPMI and protected mode, and when would you use them instead of pure real mode?

Have you packaged DOS software for distribution via DOSBox, and how do you handle configuration, sound, and file system mapping?

Why hire DOS developers on Freelancer.com

DOS expertise is rare, and finding it locally is often impossible. Freelancer.com gives you access to a global pool of programmers who have spent decades working with x86 assembly, Clipper, Turbo Pascal, and FreeDOS, alongside engineers who maintain legacy industrial systems for a living. You can compare portfolios, read verified client reviews, and shortlist freelancers on Freelancer.com whose past work matches your exact toolchain. Whether you need a one-off bug fix, a full migration of a Clipper ERP, or a DOSBox re-release of a classic game, you can post a project on Freelancer.com and receive competitive bids from specialists who already speak the language of legacy DOS software.

Legacy systems do not wait, and qualified DOS expertise is in short supply. Post a project on Freelancer.com today and connect with skilled DOS developers ready to maintain, migrate, or rebuild the software your business depends on.

What are the steps to hiring a freelance DOS developer?

Hiring a DOS developer is straightforward when your brief is specific about the toolchain, target environment, and deliverables. Because DOS work is highly specialized, the clearer you are about the language, compiler, and runtime, the more accurate the bids will be. The process below walks through posting your project, reviewing proposals, and awarding the job.

Step 1: Post your project on Freelancer.com

The quality of your project post determines the quality of bids you receive. A vague brief invites generic responses, while a precise brief filters for freelancers who genuinely work with your exact stack. Head to the post project page and fill in the brief, scope, timeline, and budget before publishing the project for freelancers to bid on.

Specify the target environment: MS-DOS, PC DOS, FreeDOS, DOSBox, DOSBox-X, vDos, or original hardware

Name the language and compiler involved, such as Clipper 5.3, FoxPro 2.6, Turbo Pascal 7, Open Watcom C, or NASM assembly

Describe the deliverable format: source code, compiled binaries, bootable disk image, DOSBox-packaged installer, or migration to a modern platform

Share technical constraints, such as memory model, hardware peripherals, sound and graphics requirements, or integration with existing data files

Include sample files, screenshots, or a description of current behavior versus expected behavior, plus your timeline and budget range

Step 2: Review bids from freelancers

Bids on a DOS project are short proposals, not just price tags. A strong proposal will show that the freelancer understood your toolchain, asked the right clarifying questions, and proposed a realistic approach. Read each bid carefully and shortlist candidates whose technical reasoning matches the brief.

Look for explicit references to the compiler, language, and DOS variant your project uses

Check whether the freelancer asked sensible clarifying questions about memory model, hardware, or file formats

Assess timeline realism, especially for migration or reverse engineering work where unknowns are high

Look for attached samples or links to past DOS work, FreeDOS contributions, or demoscene productions

Use Freelancer.com's chat to ask follow-up questions before shortlisting, such as which debugger they use or how they handle DPMI

Step 3: Evaluate freelancers and award the project

The final decision should combine proposal quality with hard evidence from each freelancer's profile. With a niche skill like DOS development, consistency across past work matters more than a single impressive sample. Weigh portfolio depth, written reviews, and verified track record together before awarding.

Review portfolio depth: multiple completed DOS projects across different compilers, languages, or hardware targets

Check star ratings and the volume of completed projects on Freelancer.com

Read written client reviews for comments on code quality, communication, and handling of legacy quirks

Confirm verified payment method, completion rate, and on-time delivery rate

Award the project and use Milestone Payments to release funds as the freelancer delivers working code, tested binaries, or completed migration phases

Can I still hire someone to maintain my old DOS business application?

Yes. Many freelancers actively maintain Clipper, FoxPro, dBase, and Turbo Pascal codebases for businesses still running them in production. They can patch bugs, add features, recompile against newer toolchains, or wrap the application in DOSBox or vDos so it runs reliably on modern Windows machines.

What is the difference between a DOS developer and a retro game developer?

There is overlap, but they are not identical. A DOS developer typically focuses on business, utility, embedded, or systems-level software, while a retro game developer specializes in graphics modes, sound hardware, and game engine techniques specific to DOS-era titles. Some freelancers do both, and you should pick based on which portfolio examples most closely match your project.

Should I migrate my DOS software to a modern platform or keep maintaining it?

That depends on cost, risk, and how active the system is. A DOS developer can audit your codebase and recommend whether to keep it on DOSBox or FreeDOS, port the business logic to a modern language, or rebuild it as a web or desktop application. Many freelancers offer the audit as a discrete first engagement before any larger migration.

Do I need a DOS developer or a general C programmer?

If your project touches real-mode memory, BIOS interrupts, segmented pointers, TSRs, or DOS-specific compilers, you need a DOS specialist. A general C programmer without DOS experience will struggle with the toolchain, the memory model, and hardware-level quirks that are second nature to a seasoned DOS developer.

Can a DOS developer recover data from old proprietary file formats?

Often yes. Reverse engineering DOS-era database and document formats is a common request, and experienced freelancers can extract records from Clipper DBF files, FoxPro tables, custom binary formats, and other legacy structures into modern formats like CSV, JSON, or SQL.