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ANC Business Solutions

5.0

485

9.2

99%

SOLIHULL, United Kingdom

$60 USD per hour

We are ANC Solutions, and we are your all-in-one stop for all your Web Development, Internet Marketing, E-commerce and BeSpoke Software needs. Our reviews from +400 happy clients will tell you more... At ANC, we pride ourselves on a stellar track record of Freelancer projects, with +500 completed to date. We sport a 5-star average review, with over 99% of our overall ratings coming in at the full 5 out of 5. We offer an extensive range of services, including: - Impementing AI and ML Technologies - Web Development -WordPress, Shopify and more - Web Scraping, Automation - Web Applications, Bespoke Software Development - API Development & Integration - Chrome Extensions - Mobile Applications -Native/Hybrid Our Tech Stack includes: php, python, .net/c#, java, .javascipts, flutter + all well-known frameworks... We have a proven track record with bespoke solutions using AI/ML. If you think ANC can help, we ensure you we can! Please reach out at your earliest convenience and we'll get started drafting a proposal for whatever project you may have!

JSON PHP JavaScript Python .NET

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Dream Solutions

5.0

458

9.4

99%

Manchester, United Kingdom

$34 USD per hour

Dream Solutions is a team of highly skilled developers, designers, and technology professionals dedicated to delivering exceptional digital solutions. We combine technical expertise, creativity, and a client-focused approach to provide high-quality services and products that meet the highest industry standards. Our team has extensive experience working with a wide range of technologies, frameworks, and software stacks, enabling us to develop tailored solutions that align with our clients unique business goals. Whether it's web development, mobile applications, custom software, UI/UX design, or cloud-based solutions, we are committed to delivering reliable, scalable, and innovative results on time and within budget. At Dream Solutions, we pride ourselves on building long-term partnerships by consistently exceeding expectations through quality, efficiency, and professional excellence.

JSON PHP Perl ASP C Programming

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caciocode

4.9

450

7.4

98%

Hayes, United Kingdom

$50 USD per hour

I can design and build software, websites & mobile apps. I am also very good at finding and fixing bugs. I can work with a lot of frameworks and CMS such as .NET, Spring and Wordpress. PHP: Laravel, Symfony, Lumen, Silex, Slim, Wordpres MEAN: NodeJS, MangoDB, Express, Angular JavaScript: Angular, JQuery, Vue, TypeScript, React Python, Django C#: ASP.NET Core, MAUI, WPF C/C++ Java: Spring, Android Rust, Kotlin, Go, R

JSON PHP Java JavaScript XML

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Umar K.

4.9

362

7.6

99%

Sheffield, United Kingdom

$20 USD per hour

Helps businesses by automating their non productive and time consuming tasks with my rock solid 10 years of experience in IT specifically in Web Scraping, Web App developments, Website Developments, Software Development and Desktop Apps. I helped businesses to grow by many folds in ecommerce, consultancy, betting, services and marketing. I have complete expertise of python including Flask & Django, Seleium, Plugins developments, backend custom developments and Rest API developments along with front end expertise in PHP and wordpress to cover anything my clients needs at any moment. Major tasks I undertake and accomplish are: 1. Software Development 2. Scripts/codes devevlopment 3. Web Scraping 4. Data mining 5. Shopify Store Development and Management 6. WooCommerce Store Development and Management 7. Bulk Product Scraping and Uploading 8. Compititor's Price analysis 9. Product/inventory Management 10. Business Databases 11. Flask/Django Web Developments 12. API developments and Integrations Apart from the Development skills, I have hands on experience of Digital marketing and Lead generation. I have managing social media targeted ads for organic growth of the businesses and their business has increased by many folds already. Accurate leads for engaging e-mail and telemarketing can also be provided for any demopraghy or any industry/niche with a solid ROI granteed. Don't hesitate to contact me and share your query or idea.

PHP C Programming Java JavaScript XML

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Adam C.

5.0

6.2

100%

Norwich, United Kingdom

$20 USD per hour

I am an expert Matlab programmer, with experience in many fields. Throughout my freelancing career I've worked on a variety of weird and wonderful things. I find excitement in applying non-conventional methods from obscure fields to tasks that wouldn't conventionally use such approaches. I am an expert MATLAB programmer and hold a first class Masters degree in Aerospace Engineering. I will consider any tasks that I am capable of completing and promise to communicate from beginning the task right through to concluding on a successful deadline

JSON Audio Services Data Processing Data Entry Engineering

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Dinesh K.

5.0

6.7

100%

Birmingham, United Kingdom

$35 USD per hour

Professional B.Sc(hons) in Computer Science, Systems,/Software Engineer and Technical Architect, with vast corporate and freelancing experience in Europe, working for top global names in consumer electronics and software. Specialist Skills with over 10+ years experience, include ============================================= ++ C++, WIndows, Linux. Embedded C/C++ ++ Porting Legacy code to modern compilers; in particular legacy MS VC++ and Borland C++ ++ UML, OOA/OOD using |MS Visio, IBM Rational tools, Enterprise ++Specialise in : Microsoft Tools, Visual Studio, VC++, Visio, Office etc; as a Developer and technical architect. ++Used Windows since the early 90s, using VC++, any Win32 API(s), MFC, Windows APIs, SQL Server etc. WinCE, windows embedded, embedded VC++ Windows Custom Credential Provider Development using VC++ and COM. I also offer soft skills such a Life Coaching, mentoring, teaching , motivation to achieve goals, and Spiritual /Divine (advanced) teachings, training and healing. Do get in touch, should you feel like benefitting from 30+ years of experience. Thanks, Success to you! Dinesh

JSON C Programming XML Windows Desktop Linux

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Arca A.

5.0

4.7

90%

Maidstone, United Kingdom

$40 USD per hour

Polygot developer with 20 years of commercial experience, I have commercial experience in a number of programming languages, and worked in a number of industries over the year. I'm professional and dependable.

JSON C Programming JavaScript .NET System Admin

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Uli T.

5.0

7.2

100%

Bournemouth, United Kingdom

$100 USD per hour

Hello and thank you for considering working with me on your project. I am Uli, an experienced web developer with expertise in various programming languages, project management and an extensive background in network and system administration. I am passionate about cyber security, constantly staying updated on the latest trends. My services include, but are not limited to: * Web and cloud hosting * Development of web apps * Debugging * Code Review * System and Task Automation * Web scraping * Bots * Network performance analysis * Network and System administration (Linux/Windows) * Penetration Testing * Web Security Consultancy * Deployment solutions * Website restoration and recovery * OSINT When accepting your project, I am committed to delivering secure, efficient, and user-friendly solutions that meet your needs exactly. Thank you for taking the time to read through my humble profile. I am looking forward to work with you on your project.

JSON PHP JavaScript XML Python

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Alexandru-Paul B.

4.8

4.0

88%

Ossett, United Kingdom

$50 USD per hour

Systems Administrator with four years experience. Problem solver, contributor and terminal junkie. My overall experience and drive to problem solving, makes me the best fit to offer the best possible solution for you. Main skills and more: CI/CD, pipelines, DevOps Apache, nginx, haproxy Bash Scripting, Markdown System Admin [Debian, CentOS, Ubuntu, Windows, Windows Server] Servers(bare metal, virtualized) [webservers, apps] Digital Signage(setup and train) [Xibo CMS] Databases MySQL, MariaDB Server monitoring[Prometheus, Grafana, Uptime-Kuma] Samba AD Server configuration Docker / docker-compose / portainer IIS, AD DS SSL / Certificates Guide creator / Trainer. Will provide advice and training on client requests.

JSON Python Windows Desktop System Admin Linux

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Clients rate our JSON Developers

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How to hire a great freelance JSON Developer

A JSON developer is a software professional who designs, builds, and maintains data structures, APIs, and integrations using JavaScript Object Notation as the primary data exchange format. Hiring a freelance JSON developer gives you targeted expertise in structuring, validating, transforming, and consuming JSON data across web, mobile, and backend systems without committing to a full-time engineering hire.

What does a freelance JSON developer do?

JSON is the dominant data format for modern APIs, configuration files, NoSQL databases, and front-end to back-end communication. A skilled JSON developer ensures your data is well-structured, schema-compliant, and efficiently transmitted between services. The work is rarely "JSON only" in isolation — it sits at the intersection of API development, data engineering, and application logic.

Typical deliverables from a JSON developer include:

RESTful and GraphQL API endpoints that return clean, consistent JSON payloads

JSON Schema definitions for validating request and response bodies

Data transformation scripts that convert XML, CSV, or SQL outputs into JSON

Configuration files for applications, CI/CD pipelines, and infrastructure as code

Postman collections, OpenAPI/Swagger specifications, and API documentation

Integrations between third-party APIs that exchange JSON data

Mock JSON servers and test fixtures for front-end development

NoSQL database modelling for MongoDB, Firebase Firestore, CouchDB, and DynamoDB

Tools and technologies a JSON developer works with

JSON development sits inside a broader stack. Strong freelancers on Freelancer.com are fluent across the tools that produce, validate, and consume JSON in production environments.

Languages and runtimes: JavaScript, TypeScript, Node.js, Python, PHP, Java, C#, Go

API frameworks: Express.js, Fastify, NestJS, Flask, FastAPI, Django REST Framework, Spring Boot, Laravel

Validation and schemas: JSON Schema, Ajv, Joi, Yup, Zod, OpenAPI 3.0, Swagger

Testing and tooling: Postman, Insomnia, curl, JSONLint, jq, Newman

Databases: MongoDB, Firebase Firestore, CouchDB, PostgreSQL JSONB, DynamoDB, Elasticsearch

Front-end consumption: React, Vue, Angular, Axios, Fetch API, Redux, TanStack Query

Integration platforms: Zapier, Make, n8n, AWS Lambda, Google Cloud Functions

Common use cases and industries

Almost every web-connected business consumes or produces JSON. Freelance JSON developers are commonly hired for:

SaaS and web applications: building and documenting public APIs for customers and partners

E-commerce: Shopify, WooCommerce, and BigCommerce integrations that sync products, orders, and inventory via JSON APIs

Fintech: connecting payment gateways, banking APIs, and accounting platforms with strict schema requirements

Mobile apps: structuring backend responses for iOS and Android clients

IoT and telemetry: designing compact JSON payloads for device-to-cloud communication

Content and publishing: headless CMS integrations with Strapi, Contentful, or Sanity

Data migration: transforming legacy data into JSON for import into modern systems

How to evaluate a freelance JSON developer

JSON proficiency on its own is table stakes — what matters is the surrounding engineering judgment. Look for candidates who treat JSON as part of an API contract, not just a string format.

Portfolio markers: public API documentation they have authored, GitHub repositories with schema files, OpenAPI specs, or sample Postman collections

Experience signals: demonstrable work with REST or GraphQL APIs, schema validation, and at least one back-end framework

Tool proficiency: comfort with Postman, JSON Schema, and a server-side language relevant to your stack

Communication: ability to explain why a particular data structure was chosen and what trade-offs it carries

Sample interview questions you can use directly:

How would you design a JSON Schema to validate a nested order object with optional discount fields?

What is the difference between JSON and JSONB in PostgreSQL, and when would you use each?

How do you handle versioning when the structure of a JSON API response needs to change?

Walk me through how you would transform a paginated XML feed into a single normalized JSON file.

What strategies do you use to keep JSON payloads small without losing readability?

Why hire JSON developers on Freelancer.com

Freelancer.com hosts a global community of millions of developers, including specialists across API development, back-end engineering, and data integration. You can post a project on Freelancer.com and receive competitive bids within hours from freelancers whose profiles show verified portfolios, client reviews, and completed project counts. Clients set their own budgets, and Milestone Payments hold funds securely until each deliverable is approved. Whether you need a one-off JSON transformation script or an ongoing API engineer, you can hire on Freelancer.com with confidence in the vetted quality of talent available.

Ready to structure your data the right way? Post a project on Freelancer.com today and connect with skilled JSON developers ready to design, validate, and integrate the JSON your applications depend on.

What are the steps to hiring a freelance JSON developer?

Hiring a JSON developer is straightforward when your brief is specific about data sources, target structures, and the systems involved. The process below helps you attract qualified bids and select a freelancer whose engineering judgment matches the work. Expect to move from posting to award within a few days for most projects.

Step 1: Post your project on Freelancer.com

The quality of your project post is the single biggest determinant of bid quality. A clear brief filters out generic bidders and attracts freelancers with directly relevant API and data experience. Head to the post project page , where you fill in the brief, scope, timeline, and budget before publishing the project for freelancers to bid on.

Describe the source data format (CSV, XML, SQL, third-party API) and the target JSON structure

Attach sample payloads, existing schemas, or OpenAPI specs if available

State the back-end language or framework you require, such as Node.js, Python, or PHP

List the systems being integrated, including any SaaS platforms, databases, or mobile clients

Specify deliverables — schema files, API endpoints, Postman collection, documentation, unit tests

Indicate your timeline and budget range so bidders can self-qualify

Step 2: Review bids from freelancers

Bids are short proposals, not just price quotes. They reveal how each freelancer interprets your data requirements, what approach they propose, and whether their estimated timeline is realistic. Read every proposal carefully and shortlist candidates whose understanding of the work clearly matches your brief.

Check whether the bid references your specific data sources and target structures

Look for clarifying questions about edge cases, validation rules, or versioning — a strong sign of experience

Confirm the freelancer proposes appropriate tools, such as JSON Schema, OpenAPI, or a relevant API framework

Assess whether the proposed timeline accounts for testing and documentation, not just initial coding

Review attached sample work — public API docs, GitHub repositories, or Postman collections

Use Freelancer.com chat to ask shortlisted candidates how they would handle a specific schema challenge from your brief

Step 3: Evaluate freelancers and award the project

The final decision combines proposal quality with profile evidence. For JSON and API work, look for consistency across multiple completed projects rather than a single polished example. Strong freelancers show repeated delivery of API-related work with positive written feedback.

Review portfolio depth, focusing on API documentation, schema files, and integration projects

Check star ratings alongside the volume of completed projects to confirm consistency

Read written client reviews for mentions of clean code, clear documentation, and reliable communication

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

Consider any verified skills or exam badges relevant to JavaScript, Node.js, Python, or API development

Award the project and use Freelancer.com Milestone Payments to release funds only as each deliverable is approved, protecting you throughout the engagement

What is the difference between a JSON developer and a general API developer?

A general API developer designs and builds the full API surface, including authentication, routing, business logic, and database access. A JSON developer focuses specifically on the data layer — schema design, validation, transformation, and serialization. In practice the same freelancer often handles both, but framing the role as "JSON-focused" is useful when your project is primarily about data structuring and integration.

Can I hire a JSON developer for a one-off project?

Yes. Many JSON tasks are short and well-scoped, such as converting a CSV export into a JSON file, writing a JSON Schema for an existing API, or building a single integration between two SaaS tools. Freelancers on Freelancer.com regularly take on small, fixed-scope JSON projects alongside longer engagements.

Do I need a JSON developer or a full back-end engineer?

If your project is mainly about defining data contracts, validating payloads, transforming files, or connecting two existing APIs, a JSON-focused freelancer is usually enough. If you need authentication, database design, hosting, and complex business logic, hire a full back-end engineer who is also fluent in JSON-based APIs.

How long does a typical JSON development project take?

Simple tasks like writing a schema or transforming a dataset can be completed in a day or two. Building a documented JSON API with validation, tests, and integration into an existing codebase typically takes one to four weeks depending on scope. A clear brief with example payloads dramatically shortens delivery time.

What should I provide before the project starts?

Share sample input and expected output data, any existing API documentation, your tech stack, and the systems the JSON will flow between. If you have draft schemas, OpenAPI specs, or Postman collections, include them. The more concrete examples you provide, the faster a freelancer can produce accurate work.