Hire the Best Informix Developers

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Thanh N.

Ho Chi Minh City, Vietnam

$30/hr
4.9
55 jobs

For now, I am working as a full-time freelancer as I am a senior full-stack developer who has extensive knowledge of the most advanced web technologies. I have rich experience in building content management systems on EPI Server CMS, Epi Server E-commerce, Umbraco, M-Files, CRM D365 Microsoft, SharePoint On-Premises & Online, Shopping carts, PIM, and many APIs including Amazon Web Services and Azure development along with more than 10 years of experience in Node.js, C#, Ruby, Python, PHP development, and React.js, Next.js, Vue.js, Angular front-end application development, and mobile programming: React Native, Flutter My responsibility I accelerate your digital transformation About me I am reliable, highly responsive to your needs, and equipped with a quality delivery mindset. Why choose me I align technical solutions with your business strategy by innovating and transforming your business to the next level Long-term Engagement I build trust and confidence by delivering what I promise – the first time and every time. Confidentiality I work under a strict Non-Disclosure Agreement (NDA). I take confidentiality very seriously. Flexible Pricing Options You can hire me on an hourly, monthly basis or fixed budget by projects. My services I offer custom build, end-to-end solutions to solve your business problems. Whether you are an individual, entrepreneur, startup, or company looking to build products or expand your team, I have got you covered. Web Development, System Integration, E-Commerce Solutions, Support & Maintenance 24/7, Mobile Development and Dedicated Teams Technologies Experts in eCommerce & CMS platforms: Sitecore, Sitecore E-Commerce, EPiServer E-Commerce and Umbraco E-Commerce. Strong in building solutions on Microsoft platforms: CRM Dynamic Microsoft, Azure Cloud Programming and support full CI/CD, building pipeline on Azure DevOps and AWS services. - CMS development (Umbraco, EPiServer, Optimizely CMS, WordPress and Sitecore) and SharePoint Online - Strong at Front-end languages: Reacts, NextJs, VueJs, Angular - Strong at Back-end languages: Node.js, C#, Ruby, Python, PHP - Mobile: React Native, Flutter, Swift and IOS Android Native - MySQL, MongoDB, Postgres - Visual Basic, WinForms application and DevExpress framework

  • Umbraco
  • Microsoft SQL Server
  • Episerver
  • ASP.NET MVC
  • Azure App Service
  • Optimizely
  • Node.js
  • .NET Core
  • Umbraco Cloud
  • Azure DevOps
  • AWS CodeDeploy
  • DevOps
  • Microsoft SharePoint Development
  • React
  • Web Application
Sairem Kishan K.

Delhi, India

$31/hr
4.6
12 jobs

Warm Greetings! Certified Cin7 Professional Certified Associate X12 Boomi Professional CargoWise Certified Professional Certified AWS Cloud Practitioner Certified AWS Technical Essentials Certified Amazon DynamoDB Service Certified AWS Partner : Amazon Q Business for IT Operations Certified AWS Partner: Generative AI Essentials Certified AWS Storage Data Migration - Knowledge Badge Readiness Path Certified AWS PartnerCast - Setting up Partner Connections for Distribution Resellers - Business I have 8 and a half years of experience in EDI implementation, development, and support. I’ve worked across multiple B2B and data integration projects for a wide range of clients and trading partners. I have successfully set up and managed EDI integrations with partners such as Amazon, UPS, Fender, FedEx, DMZ, Purolator, Velmic, SPS Commerce (including SPS Commerce Fulfillment Web EDI), Zappos, Sterling B2Bi, True Commerce, ShipStation, David Jones, and Rithum/DSCO. My expertise includes integration via Azure Logic Apps, integration testing, API integration, Altova MapForce, and SOAP-based eAdaptor integration with Azure Logic Apps. I’ve worked extensively with CRM and ERP systems, including Cin7 Core and Omni, focusing on optimization and integration. I specialize in Cin7 / DEAR Systems support, document template creation within Cin7 Core (PDF-based), PO workflow automation, MergeField form creation for quotes and invoices, Shopify integration, and supply chain operations. I’ve also implemented Cin7 Core + ShipStation integrations. In addition, I have hands-on experience with Amazon Web Services (AWS), including EC2, S3, RDS, ECS, DynamoDB, CloudFormation, and CI/CD pipelines. My background in cloud computing and DevOps complements my integration and support capabilities across enterprise platforms. I have worked in the following areas : 1. Retail Transactions 850, 855, 856, 846, 810, 997, 864 2. Logistics Transactions: 110, 210, 310, 214, 315, 204 3. I am good in EDI mapping and Trading partners on boarding. I am looking forward to work with you. Best regards Sairem

  • Electronic Data Interchange
  • Dell Boomi
  • Order Management
  • Inventory Management
  • API Integration
  • Supply Chain & Logistics
  • Amazon Web Services
  • Amazon EC2
  • Amazon ECS
  • ShipStation
  • Shopify
  • CRM Software
  • Integration Testing
  • ERP Software
Isaac J.

Kimberling City, Missouri

$115/hr
4.9
179 jobs

🌟 Expert-Vetted Talent - Recognized in Upwork's top 1% of Talent ✅ Established Track Record of Hours and Earnings 🚀 Fastest Response Times 💯 100% Job Success Awarded by Clients 🔝 Top Rated Plus by Upwork, Freelancer and Agency 🔎 Searching for New Opportunities and Problems to Solve Hello and welcome, thank you for considering me for your project. My Upwork profile’s stats clearly demonstrate both my expertise and the value I add to every team that brings me on. The thousands of hours clocked on this platform alone speak to my years of experience in Software Development, and the total earnings shows a glimpse of how valuable that time has been for clients. I am available and ready to answer specific questions about your project’s current problem, next opportunity, or my fit for it. Shall we get to work? Send a message or an invite now and I will be right with you. 𝐖𝐡𝐲 𝗖𝗹𝗶𝗲𝗻𝘁’𝘀 𝐂𝐡𝐨𝐨𝐬𝐞 𝐌𝐞: 1. 𝗘𝘅𝗽𝗲𝗿𝗶𝗲𝗻𝗰𝗲 𝗮𝗻𝗱 𝐄𝐱𝐩𝐞𝐫𝐭𝐢𝐬𝐞: Decades of experience bring a deep understanding of various languages, frameworks, platforms and tools, common and uncommon pitfalls, and alternative solutions. 🗯️ “He was very responsive to our messages and explained what was needed in our project clearly. He is definitely an expert in his work.” 2. 𝗘𝗳𝗳𝗲𝗰𝘁𝗶𝘃𝗲 𝗣𝗿𝗼𝗯𝗹𝗲𝗺 𝗦𝗼𝗹𝘃𝗶𝗻𝗴: I have a proven track record and knack for solving complex problems and providing customized solutions for specific business needs and challenges. 💭 “Isaac was able to quickly discern what I needed and delivered…” 3. 𝗦𝘆𝘀𝘁𝗲𝗺 𝗩𝗶𝗲𝘄 𝗮𝗻𝗱 𝗖𝗼𝗺𝗽𝗿𝗲𝗵𝗲𝗻𝘀𝗶𝗼𝗻: Years of experience and diverse projects have helped me accumulate a broad set of skills and tools. I use this experience to the advantage of my client’s projects in not only accomplishing tasks, but in advising and consulting on potential challenges and opportunities. 💬 “LIFE SAVER!!! I have now use(d) Issac for two separate jobs now and will be bringing him on for some regular hours. Hopefully we get some funding and I can do even more with him. GREAT DEVELOPER” 𝐌𝐲 𝐂𝐨𝐫𝐞 𝐄𝐱𝐩𝐞𝐫𝐭𝐢𝐬𝐞: Python|Django|PHP | MySQL | Laravel | WordPress | CodeIgniter | ExpressionEngine | CSS | HTML | JavaScript | Express.js | React.js | Bootstrap | PostgreSQL | NoSQL | Linux | Apache | Nginx | API | Git | SVN | Amazon Web Services | AWS EC2 | 𝐒𝐞𝐫𝐯𝐢𝐜𝐞𝐬 𝗜 𝐎𝐟𝐟𝐞𝐫: 𝐅𝐫𝐨𝐧𝐭 𝐚𝐧𝐝 𝐁𝐚𝐜𝐤-𝐄𝐧𝐝 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭: Planning, Design, Documentation, Coding, Testing, Debugging, Deployment, Monitoring, and Maintenance. 𝐒𝐲𝐬𝐭𝐞𝐦 𝐀𝐝𝐦𝐢𝐧𝐢𝐬𝐭𝐫𝐚𝐭𝐢𝐨𝐧: Cloud infrastructure Design, Deployment, Optimization, Maintenance, Scaling, Recovery and Backup, Troubleshooting, and Cost Management. 𝐃𝐚𝐭𝐚𝐛𝐚𝐬𝐞 Management: Architecting, Optimization, Monitoring, Recovery, Updating, and Merging. 𝐏𝐫𝐨𝐣𝐞𝐜𝐭 𝐌𝐚𝐧𝐚𝐠𝐞𝐦𝐞𝐧𝐭: Planning, Project Requirements, Task Detailing, Developer Support and Feedback, Problem Resolution, Progress Monitoring, Qualification Testing, and Stakeholder Communication.

  • IBM Informix
  • JavaScript
  • MySQL
  • PHP
  • API
  • React
  • Amazon Web Services
  • Web Development
  • CSS
  • Python
  • PostgreSQL
  • Database Architecture
  • RESTful API
  • Node.js
  • Database Design
  • Laravel
  • Linux System Administration
  • CodeIgniter
  • SOAP
  • Unix System Administration
  • Amazon EC2
  • jQuery
  • Java
Nikunja Behari G.

Tangail, Bangladesh

$25/hr
4.7
34 jobs

Legacy PHP apps that crash, slow down, or that nobody wants to touch — I take them over and make them stable. 13+ years in Symfony, Laravel, Python and DevOps, with 6,900+ hours and 100% Job Success on Upwork. Most of my work starts the same way: an existing production system, an original developer who is gone, and a client who needs it to just work again. I read unfamiliar codebases fast, find the real cause instead of patching symptoms, and leave the system in a state the next person can maintain. WHAT I DO • Rescue & stabilize production apps — crashes, broken deploys, silent failures • Symfony & Laravel development and legacy upgrades (PHP 5 to 8, Symfony 2 to 6) • REST API development and third-party integrations • Performance tuning — Redis caching, Elasticsearch, query optimization • DevOps — Docker, AWS, DigitalOcean, Linux, CI/CD, RabbitMQ workers & schedulers • ERPNext / Frappe customization, deployment and integrations PROOF THAT CLIENTS KEEP ME My two longest engagements ran 1,463 hours and 1,431 hours with the same clients — one of them for over three years. Across 26 contracts I average around 260 hours per client, because the work does not come back broken. RESULTS I'VE DELIVERED • Migrated and dockerized a legacy Symfony 3 application into a reproducible local + production setup • Cut response times on a high-traffic directory platform with Redis caching and Elasticsearch tuning • Fixed multi-party WebRTC stability on iOS after months of intermittent dropouts • Resolved queue and worker failures in ERPNext following a server migration BEST FIT FOR • Existing systems that need rescuing, upgrading or scaling • Apps hitting performance or reliability limits • Long-term maintenance and ongoing development partnerships Not a fit for: brand-new WordPress sites, template theme work, or one-hour "just make it work" fixes with no access to the codebase. If you have a live system that needs someone who can step in, understand it, and make it solid — send me the details and I'll tell you honestly whether I'm the right person. Tech: PHP · Symfony · Laravel · Python · Frappe/ERPNext · Node.js · React · Vue · Angular · MySQL · Redis · Elasticsearch · RabbitMQ · Docker · AWS · DigitalOcean · Linux · REST API · CI/CD · WebRTC

  • PHP
  • Symfony
  • Laravel
  • ERPNext
  • ERP Software
  • REST API
  • Python
  • Docker
  • MySQL
  • Amazon Web Services
  • Linux System Administration
  • CI/CD
  • Redis
  • Node.js
  • React
Ciro F.

Lentini, Italy

$25/hr
4.9
214 jobs

I am the owner of Business Paper X , a software house based in Catania, Italy, working with clients across Italy and Europe. We cover the full path from raw data to a working application: extraction and integration, data modeling, backend, interface, release, and ongoing support. One partner, no handoffs between three different vendors. Most of the projects that reach us start the same way. Information is scattered across spreadsheets, a legacy management system, and two SaaS platforms that do not talk to each other. Reports are copied by hand. The off-the-shelf tool almost fits the process, but not quite. We replace that with something built around how the business actually works. WHAT WE BUILD Web apps and portals — multi-user platforms with roles and permissions, secure and built to scale Custom CRM — client and pipeline management shaped around your commercial process Management and warehouse systems — inventory, logistics, and real-time operational control Business intelligence — Power BI and custom dashboards with automated refresh Data engineering — integration from REST APIs, databases, eCommerce, social platforms, and existing ERPs Mobile apps — iOS and Android, native and cross-platform, backend and integrations included TECHNOLOGY Frontend: React, Next.js, TypeScript, Tailwind Backend: Node.js, Python, REST APIs, PostgreSQL Data & BI: Power BI, SQL, MySQL, Amazon Redshift Mobile: iOS, Android, React Native Cloud & infrastructure: AWS, Supabase, Docker, Stripe HOW WE WORK Analysis and strategy — we map the real process before proposing an architecture Design and architecture — data model, relations, and KPIs defined first Development — iterative, with working builds you can see and test Testing and release — verified calculations, verified data, then deployment Support and evolution — maintenance, updates, and new features over time

  • Dashboard
  • SQL
  • Data Visualization
  • Microsoft Power BI
  • API Integration
  • Database Modeling
  • Analytics
  • Statistical Analysis
  • Data Engineering
  • Data Analysis
  • Visualization
  • Power Tool
  • Database Management
  • Market Research
  • DataTables
Isaac Claver F.

Lima, Peru

$60/hr
4.2
59 jobs

Full-stack developer with vast knowledge of web and mobile applications and wide experience working as a Linux system administrator. I work for over 18 years on IT projects. The latest 10 years I work with the Symfony and Laravel frameworks and also I work with Flutter SDK for mobile development. Some about my strong skills are listed here: Programming Languages: - PHP, C#, NodeJS, Dart Frameworks : - Symfony - Laravel - Flutter Symfony components: - Twig extensions - ORM / ODM Programming tools for Front-end: - VueJS with Bootstrap Web Services: - Rest API - JWT (JSON Web Tokens) - OAuth authorization and authentication Videoconference: - Setup BigBlueButton - Setup Zoom API - Setup Webex API Databases: - Mysql / MariaDB - Postgresql - MongoDB - Microsoft SQL server

  • SQL
  • Docker
  • SCSS
  • Bootstrap
  • Git
  • Doctrine ORM
  • RESTful API
  • Twig
  • Custom PHP
  • API Integration
  • Database Development
  • PHP
  • Symfony
  • Microsoft SQL Server
  • MySQL

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Don't just take our word for it

What does an Informix developer do?

An Informix developer builds server-side database logic and client applications for the IBM Informix database server. This role extends core database capabilities by coding stored routines, triggers, and custom DataBlade modules that handle complex data types. The work focuses on optimizing how applications interact with Informix through specific APIs like ESQL/C and JDBC.

  • Write and deploy Structured Procedure Language (SPL) routines, including stored procedures and functions, to automate database tasks. Define SQL triggers that execute specific actions when data changes in targeted tables, ensuring consistent data integrity across the system.
  • Develop client applications that connect to the Informix server using supported interfaces such as ESQL/C, JDBC, or ODBC drivers. Code efficient data-access layers that query the database and call server-side routines without introducing latency or connection errors.
  • Create DataBlade modules to extend the database engine with new data types and specialized routines. Use the DataBlade Developers Kit tools, such as BladeSmith, to build, debug, and integrate these modules so they function seamlessly within the Informix environment.
  • Author external-language user-defined routines, often in C, that execute SQL commands via the DataBlade API. Implement these routines to perform high-performance computations or data transformations that standard SQL cannot handle efficiently.

How to hire an Informix developer on Upwork

Step 1: Post a job

Define your database requirements clearly so candidates understand the specific Informix tasks they will handle. The Job Post Generator powered by Uma™, Upwork's Mindful AI helps you draft a precise description in seconds. Describe your needs in a few sentences and Uma drafts a job post for the role. You can write a new post, update a saved draft, or reuse an existing post.

  • Specify whether the work involves building SPL routines, creating triggers, or developing client applications using ESQL/C or JDBC.
  • List required tools such as the IBM Informix DataBlade Developers Kit if the project requires custom DataBlade modules.
  • Clarify if the developer must write external-language user-defined routines in C that execute SQL via the DataBlade API.

Step 2: Evaluate candidates

Look for portfolios that demonstrate direct experience with IBM Informix server-side logic and client connectivity. Uma can run instant video interviews and build shortlists with side-by-side comparisons to help you assess technical fit quickly.

  • Check for deployed SPL procedures and functions that handle complex database events and table triggers.
  • Verify experience with DataBlade module development using tools like BladeSmith to extend server capabilities.
  • Confirm proficiency in connecting applications to Informix databases using supported APIs such as ODBC or JDBC.

Step 3: Interview your top choices

Discuss specific technical challenges related to Informix architecture and data access patterns. Interviews can be scheduled and conducted within Upwork Messages with an immediate transcript and summary after each one.

  • Ask how they debug DataBlade modules and ensure SQL execution paths function correctly within C-based UDRs.
  • Request examples of client applications they built that query Informix databases using ESQL/C or similar interfaces.
  • Explore their approach to designing database behavior using DDL statements and stored routine definitions.

Step 4: Agree on scope and begin work

Set clear milestones for delivering database objects and application components. Use Upwork Messages and the contract workroom for communication and project management, plus identity verification, payment protection, hourly tracking, and project funds for security.

  • Define deliverables such as compiled DataBlade modules or tested SPL routines ready for deployment.
  • Establish testing criteria for external-language routines to verify they execute SQL without errors.
  • Schedule regular check-ins to review progress on client API integration and database object creation.

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The rates and information provided in this article are based on current data and industry sources available at the time of publication. Freelance rates can vary depending on factors such as experience, location, project scope, and market conditions. Readers are encouraged to conduct their own research to confirm current rates and trends, as this information may change over time.

How much does hiring an Informix developer cost?

$500-$1,500 per project is a typical range for focused Informix developer work. Final pricing depends on scope, technical complexity, required integrations, source-material quality, revision needs, and the freelancer's experience level.

SPL routine development

$500-$1,200/project

Entry-level to mid-level
  • Authored SPL functions and procedures for database logic
  • Created SQL triggers tied to specific table events
  • Compiled DDL scripts for routine installation

Client API integration

$1,200-$2,500/project

Mid-level
  • Built data-access code using ESQL/C or JDBC
  • Implemented routines to call server-side logic
  • Documented client interface methods and parameters

DataBlade module creation

$2,500-$4,500/project

Mid-level to senior-level
  • Defined new data types via DataBlade API
  • Compiled DataBlade modules using DBDK tools
  • Verified module behavior within Informix server

External UDR implementation

$4,500-$7,000/project

Senior-level
  • Authored external-language user-defined routines
  • Configured SQL execution paths for C UDRs
  • Generated execution metrics for routine optimization

Full database extension

$7,000-$12,000/project

Expert-level
  • Deployed complex DataBlade modules with custom routines
  • Built end-to-end apps using Informix client APIs
  • Submitted comprehensive test results for all components

Frequently asked questions

Is hiring an Informix developer worth it?

For most businesses, yes: hiring an Informix developer is worthwhile. These specialists build server-side routines and client applications that rely on specific IBM Informix APIs. They extend database capabilities by coding DataBlade modules and external-language user-defined routines.

How do I evaluate Informix developer candidates?

Review code samples that show SPL procedures or triggers deployed to an Informix server. Ask candidates to explain how they used the DataBlade API to create a C-based user-defined routine.

What tools does an Informix developer use?

An Informix developer uses the DataBlade Developers Kit with BladeSmith to build modules. They also write client access code using ESQL/C, JDBC, or ODBC drivers.

What deliverables does an Informix developer produce?

They submit deployed SPL routines and database triggers tied to table events. They also export DataBlade modules that add new data types and routines to the server.