Build software that helps push AI beyond the obvious. Fusion CX is hiring Software Engineers with strong Python and Docker expertise in Kolkata, India for a contractual opportunity supporting a frontier AI data initiative. If you are an experienced backend engineer who works confidently with Python, Docker, REST APIs, microservices, Git, and AI coding assistants, this opportunity lets you apply your engineering skills to the development of infrastructure, connectors, workflows, and training data used to develop and evaluate AI agents.
You will build and test backend applications, develop and extend SaaS connectors, mine workflows for realistic AI tasks, and use AI coding agents throughout development, QA, and validation.
Job Description:
About the Role
As a Software Engineer – Python & Docker, you will support a frontier AI data initiative requiring strong software engineering expertise to build infrastructure and training data used to develop and evaluate AI agents.
Depending on your assigned track, you may work on backend applications and SaaS connectors, task and data mining, workflow development, quality validation, and evaluation rubrics. You will also use AI coding agents throughout development, QA, and validation activities.
Key Responsibilities
- Build Python backend applications that replicate existing SaaS tools such as Slack, Linear, Jira, Notion, Gmail, and wikis, including implementing integrations and standing up full-service backend functionality.
- Perform thorough backend testing and integration validation to ensure each connector behaves faithfully like the system it emulates.
- Adapt and extend previously built connectors as needed, and test existing connectors internally before they are treated as complete.
- Build new connectors from scratch where required, within agreed delivery timeframes.
- Conduct data mining and task mining to identify representative workflows suitable for long-horizon task development.
- Author realistic tasks derived from mined data and workflows.
- Verify task and data quality, realism, and correctness through structured QA.
- Write clear evaluation rubrics that define correct, partially correct, and deficient work.
- Use AI coding agents proficiently throughout all development, QA, and validation work.
- Collaborate across the connectors and tasks tracks.
- Participate in onboarding, calibration, and quality-review cycles.
- Deliver assigned work to the expected quality bar and on agreed milestones.
Job Requirements:
Required Skills & Experience
- 3+ years of overall experience.
- Strong proficiency in Python, with experience using FastAPI, Flask, or Django for backend software development.
- Proficiency with Git and Docker, along with basic software pipeline setup.
- Experience building scalable backend applications, REST APIs, and microservices.
- Proficiency in using AI coding assistants such as Codex, Claude Code, Cursor, GitHub Copilot, or similar as part of daily development workflows.
- Strong understanding of software engineering best practices, including version control, testing, and code quality.
- Strong analytical and problem-solving skills with attention to detail.
- Ability to work independently while collaborating effectively within distributed engineering teams.
- Excellent written and verbal communication skills.
Nice to Have
- Experience building connectors or integrations for SaaS platforms.
- Knowledge of evaluation frameworks, QA methodologies, and rubric creation for AI datasets.
- Experience developing realistic workflows for long-horizon AI tasks.
- Previous experience building AI data tasks.
Work Details
Location: Kolkata, India
Work Mode: WFH
Employment Type: Contractor – Pay Per Task
Work Commitment: Flexible hours, with a minimum requirement to complete and get approved at least 1 task per day.
Start Date: Immediate
LinkedIn Requirement: A LinkedIn profile is mandatory for review. Please ensure your resume includes the LinkedIn profile link.
Why Join Fusion CX?
Software engineering for AI is increasingly about more than building conventional applications. In this opportunity, your backend expertise will be applied to the systems, connectors, workflows, and data that help train and evaluate AI agents.
As a Software Engineer – Python & Docker, you’ll work on technically demanding assignments involving backend development, SaaS integrations, AI-assisted coding, data and task mining, testing, and structured evaluation. The flexible task-based model also gives experienced engineers the opportunity to contribute according to their availability while meeting the required daily delivery commitment.
What You Will Gain
- Work on frontier AI data and AI agent development projects.
- Apply Python backend engineering skills to AI-focused software development.
- Gain experience building and testing connectors for SaaS platforms.
- Work with technologies and practices including Python, Docker, Git, REST APIs, and microservices.
- Strengthen your experience using AI coding assistants such as Claude Code, Codex, Cursor, or GitHub Copilot.
- Gain exposure to AI dataset QA, evaluation frameworks, task mining, and rubric creation.
- Develop experience creating realistic workflows for long-horizon AI tasks.
- Work in a fully remote environment with flexible working hours while contributing to cutting-edge AI projects.
Evaluation Process
The evaluation process includes:
- Internal resume review
- Online assessment focused on Python and Docker
Apply Today
If you’re searching for Software Engineer jobs in Kolkata, Python Developer jobs in Kolkata, Python backend developer jobs, Docker jobs, backend software engineer jobs, AI software engieering jobs, AI data jobs, remote software engineer jobs, or contract Python developer jobs, apply today and use your engineering expertise to contribute to projects shaping the next generation of AI systems.
Requires 3+ years' experience, strong Python and backend development skills, Docker, Git, REST APIs, microservices, AI coding assistants, testing, analytical ability, and strong communication.
Key Responsibilities
- building applications
- developing connectors
- testing backends
Skills & Tools
Python, Docker, REST APIs, Git, FastAPI, Flask, Django, Codex, Claude Code, Cursor, GitHub Copilot, Slack, Linear, Jira, Notion, Gmail
Job Details
- Category: Software Development
- Seniority: Mid Level
- Commitment: Contract
- Workplace: Remote — Kolkata, West Bengal, India
- Languages: English
About Fusion CX
A technology services company developing software, data, and customer experience solutions. — Industry: Information Technology