Kartik is available for hire

Kartik Arora

Verified Expert in Engineering

Back-end Developer

Bengaluru, Karnataka, India

Toptal member since September 29, 2022

Expertise

Algorithms Integration Full-stack Back-end Developers Cloud Engineering API Cloud Architecture Web Development Multithreading Front-end AWS RDS

Bio

Kartik is passionate about building teams, products, and tech for startups. He has five years of experience as a first back-end developer, though he sometimes ventures into the front end and DevOps. He has built and scaled multiple products and teams from scratch to multi-million dollar ARRs. Kartik also has freelance experience with Karat in the USA, and BarRaiser in India, for whom he conducted over 500 technical interviews as an interview expert.

Portfolio

Keep Technologies

JavaScript, Node.js, Next.js, PostgreSQL, Redis, MongoDB, Python, React...

Karat

Interviewing, Technical Consulting, Scalability, Software Architecture, HTML...

Zecko

Java, Spring Boot, JavaScript, Node.js, TypeScript, MySQL, Redis...

Experience

Node.js - 6 years
MongoDB - 5 years
MySQL - 5 years
Interviewing - 4 years
TypeScript - 4 years
Amazon Web Services (AWS) - 4 years
Java - 3 years
Spring Boot - 3 years

Availability

Part-time

Preferred Environment

Spring Boot, Java, Ruby, Ruby on Rails (RoR), JavaScript, Node.js, Java 11

The most amazing...

...thing I've developed from scratch is the back-end of the Cult.fit eCommerce store. I also led the team and scaled the project to a multi-million dollars ARR.

Work Experience

Tech Lead and Product Manager

2023 - PRESENT

Keep Technologies

Spearheaded the implementation of transaction monitoring for all outgoing transactions from Keep card and banking accounts, enhancing security and risk management.
Led the customer application process for Keep, collaborating closely with both the sales and operations teams to optimize and simplify our KYB, KYC, fraud detection, and underwriting workflows. Implemented data gathering and verification procedures.
Launched several developer productivity tools for teams across Keep, like advanced Git flows and streamlined deployment pipelines.

Technologies: JavaScript, Node.js, Next.js, PostgreSQL, Redis, MongoDB, Python, React, Front-end, Front-end Development, Bower Front-end Dependency Manager, Webflow, Front-end Build Tools, Google Cloud, Web Scraping, Scraping, Data Scraping, Large-scale Web Crawlers, Web Crawlers, Algorithms, Workflow, Dashboard Development, Integration, Responsive, Responsiveness, Postman, HubSpot, Django, Springbot, Artificial Intelligence (AI), Data Engineering, Search Engines, Generative Pre-trained Transformers (GPT), Data Science, Tailwind CSS, Canvas, Chatbots, Amazon Elastic Container Registry (ECR), Cron, Forms, Design, Bubble, No-code Development

Interview Expert

2022 - PRESENT

Karat

Conducted more than 100 interviews through the Karat platform.
Contributed to the hiring process of leading companies operating across the globe.
Gained experience in conducting language agnostic interviews.

Technologies: Interviewing, Technical Consulting, Scalability, Software Architecture, HTML, HTML5, JSON, C++, Microservices Architecture, Java, SQL, Relational Databases, Java 11, Microservices, Back-end Development, Client-server Model, IT Consulting, Event-driven Architecture, Distributed Systems, Consulting, Technical Architecture, Low Latency, Multithreading, Back-end, Back-end Performance, Markdown, cURL Command Line Tool, IT, Back-end Architecture, Writing & Editing, Python, React, Front-end, Flask, Front-end Development, Front-end Build Tools, Algorithms, Workflow, Integration, Postman, Springbot, Data Science, Amazon Elastic Container Registry (ECR), Cron, Forms, Design, Bubble, No-code Development

Co-founder and CTO

2022 - PRESENT

Zecko

Spearheaded the development of Zecko, a pioneering platform offering universal eCommerce APIs and no-code widgets. This innovation enables digital platforms to sell products of any DTC brand seamlessly.
Played a crucial role in successfully integrating Shopify infrastructure to rapidly develop an MVP, showcasing deep understanding and practical skills in utilizing Shopify's capabilities to their fullest potential.
Focused on creating an intuitive user experience, enabling easy navigation and interaction, a critical factor for the success of online sales platforms.
Led a multidisciplinary team through the challenging 0-to-1 product development journey, ensuring timely delivery and quality of eCommerce solutions.
Played a pivotal role in shaping the strategic direction of eCommerce initiatives, aligning them with the company's broader business goals.
Demonstrated proficiency in leveraging Shopify APIs to create robust, scalable eCommerce solutions.
Developed custom, no-code widgets to enhance functionality and user engagement on Shopify-based platforms.
Platform Scalability and Integration: I ensured that the eCommerce platform built on Shopify was scalable and seamlessly integrated with other business systems, demonstrating his comprehensive technical acumen.

Technologies: Java, Spring Boot, JavaScript, Node.js, TypeScript, MySQL, Redis, Amazon Web Services (AWS), GraphQL, Web Scraping, Scraping, Web Development, Full-stack, Back-office System Development, CTO, Architecture, APIs, Back-end, REST APIs, Microservices, jQuery, NGINX, CSS, Headless Software, Cloud, Scalability, Third-party APIs, Security, Software Architecture, HTML, HTML5, Shopify API, Shopify, API Integration, Spring, Technical Writing, Spring MVC, Spring Security, Payment APIs, Online Payments, Full-stack Development, JSON, Front-end, Technical Leadership, Software Design, Scalable Architecture, SDKs, Software Packaging, DevOps, Documentation, Amazon EC2, Amazon S3 (AWS S3), AWS Lambda, Amazon RDS, Amazon CloudFront CDN, Amazon CloudWatch, Microservices Architecture, Enterprise Application Architecture, Enterprise Architecture, SQL, Relational Databases, Java 11, Ubuntu, Bash Script, Git, Linux, VM, GitOps, DevOps Engineer, Back-end Development, Roadmaps, Solution Architecture, Client-server Model, AWS Elastic Beanstalk, Typeform.io, Java EE, Docker, Data Analysis, Event-driven Architecture, Startups, UI Development, Distributed Systems, SaaS, eCommerce, Pricing Consulting, Technical Architecture, Leadership, Swagger, Low Latency, Multithreading, Minimum Viable Product (MVP), Product Development, Estimations, Cloud Platforms, Zapier, Lambda Functions, Lambda Architecture, API Connectors, XML, Databases, Database Administration (DBA), Back-end Performance, Technical Documentation, Logistics, Markdown, cURL Command Line Tool, IT Project Management, IT, Cloud Architecture, Back-end Architecture, Writing & Editing, Python, React, Flask, Front-end Development, Front-end Build Tools, Data Scraping, Large-scale Web Crawlers, Web Crawlers, Scrapy, Workflow, Dashboard Development, Integration, Wix, Responsive, Responsiveness, Postman, Django, Springbot, Artificial Intelligence (AI), Data Engineering, Search Engines, Generative Pre-trained Transformers (GPT), Data Science, Tailwind CSS, Canvas, Chatbots, Amazon Elastic Container Registry (ECR), Cron, Forms, Design, Bubble

Interview Expert

2020 - PRESENT

BarRaiser

Integrated the team from the beginning of the project and helped in the early stage of product development.
Conducted 200+ interviews over the last three years.
Contributed to the hiring process of several startups and leading companies operating across the globe.

Technologies: Technical Consulting, Scalability, Software Architecture, JSON, C++, Microservices Architecture, Java, SQL, Relational Databases, Java 11, Git, Microservices, Back-end Development, Client-server Model, IT Consulting, Event-driven Architecture, Startups, Distributed Systems, Consulting, Technical Architecture, Low Latency, Multithreading, Back-end, Databases, Back-end Performance, Markdown, cURL Command Line Tool, IT, Back-end Architecture, Writing & Editing, Python, React, Front-end, Flask, Front-end Development, Algorithms, Workflow, Integration, Springbot, Data Engineering, Search Engines, Amazon Elastic Container Registry (ECR), Forms, Bubble, No-code Development

Founding Engineer

2020 - 2021

CureFit

Helped build an industry-leading CRM solution from scratch.
Owned an in-house segmentation platform that has become the most adopted and largest-scale service at Curefit.
Envisioned and implemented a cheaper and better alternative to Segment.io. The in-house segmentation platform I helped build was the first near-real-time segmentation engine in the world.

Technologies: Java, Spring Boot, Redis, MongoDB, MySQL, Amazon Web Services (AWS), JavaScript, TypeScript, Web Development, Full-stack, Back-office System Development, Architecture, APIs, Back-end, REST APIs, Microservices, jQuery, CSS, Headless Software, Cloud, Scalability, Third-party APIs, Security, Software Architecture, HTML, HTML5, API Integration, Spring, Technical Writing, Spring MVC, Spring Security, JSON, Technical Leadership, Software Design, Scalable Architecture, SDKs, Software Packaging, DevOps, Documentation, Amazon EC2, Amazon S3 (AWS S3), AWS Lambda, Redis Cache, Amazon RDS, Amazon CloudWatch, Node.js, Microservices Architecture, Serverless Architecture, OpenAPI, Enterprise Application Architecture, Enterprise Architecture, SQL, Relational Databases, Java 11, Ubuntu, Bash Script, Git, Linux, VM, GitOps, DevOps Engineer, Back-end Development, Roadmaps, Solution Architecture, Client-server Model, AWS Elastic Beanstalk, Typeform.io, Java EE, Docker, Data Analysis, Event-driven Architecture, Startups, Distributed Systems, SaaS, Pricing Consulting, Technical Architecture, Leadership, Swagger, Jest, Low Latency, Multithreading, Minimum Viable Product (MVP), CI/CD Pipelines, Product Development, Estimations, Cloud Platforms, CRM APIs, YAML, Lambda Functions, Lambda Architecture, API Connectors, XML, Databases, Database Administration (DBA), Back-end Performance, Technical Documentation, Markdown, cURL Command Line Tool, Analytics, Data Pipelines, Reports, IT Project Management, IT, Cloud Architecture, Back-end Architecture, Writing & Editing, React, Front-end, Front-end Development, Front-end Build Tools, Web Scraping, Scraping, Data Scraping, Large-scale Web Crawlers, Web Crawlers, Scrapy, Algorithms, Dashboard Development, Integration, Wix, Responsive, Responsiveness, Postman, HubSpot, Django, Design

Founding Engineer

2018 - 2020

CureFit

Led the back end for Cultgear engineering and built the eCommerce back end from scratch.
Handled several areas of expertise, from the design and development of features in quick cycles to deployment for production, ensuring adherence to best practices.
Worked on finding the right balance of current needs and long-term ideals and designing systems iteratively.
Contributed to product management, designed core and innovative eCommerce features, developed the system, and led the implementation cycle with a team of three other engineers.
Hired and grew the core engineering and product teams through a rigorous interviewing process, keeping high-quality standards.

Technologies: Ruby, Ruby on Rails (RoR), MySQL, Redis, JavaScript, TypeScript, Amazon Web Services (AWS), Web Development, Full-stack, Architecture, APIs, Back-end, REST APIs, Microservices, jQuery, NGINX, CSS, Cloud, Scalability, Third-party APIs, Security, Software Architecture, HTML, HTML5, API Integration, Technical Writing, Payment APIs, Online Payments, Full-stack Development, JSON, Front-end, CoffeeScript, RSpec, Sidekiq, Technical Leadership, Software Design, Scalable Architecture, SDKs, Software Packaging, DevOps, Documentation, Amazon EC2, Amazon S3 (AWS S3), AWS Lambda, Redis Cache, Amazon RDS, Amazon CloudWatch, Node.js, Microservices Architecture, Serverless Architecture, OpenAPI, Enterprise Application Architecture, Enterprise Architecture, Unit Testing, Integration Testing, SQL, Relational Databases, Ubuntu, Bash Script, Git, Linux, VM, GitOps, DevOps Engineer, Back-end Development, Roadmaps, Solution Architecture, Client-server Model, AWS Elastic Beanstalk, Event-driven Architecture, Startups, UI Development, Distributed Systems, eCommerce, Technical Architecture, Leadership, Swagger, Jest, Low Latency, Multithreading, Minimum Viable Product (MVP), CI/CD Pipelines, Product Development, Estimations, Cloud Platforms, YAML, Lambda Functions, Lambda Architecture, API Connectors, XML, Databases, Database Administration (DBA), Back-end Performance, Technical Documentation, Logistics, Markdown, cURL Command Line Tool, IT Project Management, IT, Cloud Architecture, Back-end Architecture, Ruby Gems, Writing & Editing, React, Flask, Front-end Development, Front-end Build Tools, Web Scraping, Scraping, Data Scraping, Large-scale Web Crawlers, Web Crawlers, Scrapy, Algorithms, Workflow, Dashboard Development, Integration, Responsive, Responsiveness, Postman, Springbot, Search Engines, Tailwind CSS

Software Engineer

2017 - 2018

1mg

Helped rewrite 1mg's complete codebase from Python to Ruby on Rails (RoR), which included defining a new system design, re-thinking business logic, identifying chunks on an extensive system, and planning the rewrite keeping downtime to a minimum.
Contributed to rewriting the complete codebase of Droplet, a subsidiary of 1mg, moving from PHP to Ruby on Rails (RoR).
Progressed to primary code reviewer just a few months after joining the team.

Technologies: Ruby on Rails (RoR), Ruby, PostgreSQL, Web Development, Full-stack, Architecture, APIs, Back-end, REST APIs, Microservices, jQuery, CSS, Cloud, Scalability, Third-party APIs, Software Architecture, API Integration, JSON, CoffeeScript, RSpec, Sidekiq, Software Design, Scalable Architecture, SDKs, Software Packaging, Documentation, GitLab, Amazon EC2, Amazon RDS, Microservices Architecture, Enterprise Application Architecture, Enterprise Architecture, Unit Testing, Integration Testing, SQL, Relational Databases, Ubuntu, Bash Script, Git, Linux, VM, Back-end Development, Client-server Model, Event-driven Architecture, Startups, Distributed Systems, Technical Architecture, Low Latency, Multithreading, Cloud Platforms, XML, Databases, Back-end Performance, Technical Documentation, Markdown, cURL Command Line Tool, IT, Cloud Architecture, Back-end Architecture, Ruby Gems, Writing & Editing, Front-end Development, Algorithms, Workflow, Dashboard Development, Integration, Wix, Postman, Springbot, Search Engines, Tailwind CSS, Cron, Design, No-code Development

Software Engineer

2017 - 2017

FastFox

Introduced a new repository that acts as the central library for all FastFox repositories and is used as a Node.js module.
Researched, designed, and implemented a logging system to log all customer actions using RabbitMQ and MongoDB in collaboration with another developer.
Implemented, in collaboration with another developer, a dynamic panel and back-end APIs for actions to be used by the requirement gathering team.

Technologies: JavaScript, PostgreSQL, RabbitMQ, Node.js, MongoDB, Web Development, Full-stack, Architecture, APIs, Back-end, REST APIs, Microservices, jQuery, CSS, Cloud, Scalability, Third-party APIs, Software Architecture, HTML, HTML5, API Integration, Full-stack Development, JSON, Front-end, Software Design, Scalable Architecture, SDKs, Software Packaging, Documentation, Microservices Architecture, Enterprise Application Architecture, Enterprise Architecture, SQL, Relational Databases, Ubuntu, Bash Script, Git, Linux, VM, Back-end Development, Client-server Model, Startups, UI Development, Distributed Systems, Technical Architecture, Low Latency, XML, Databases, Back-end Performance, Technical Documentation, Markdown, cURL Command Line Tool, IT, Cloud Architecture, Back-end Architecture, Writing & Editing, Front-end Development, Bower Front-end Dependency Manager, Algorithms, Dashboard Development, Integration, Responsive, Responsiveness, Postman, Springbot, Data Engineering, Search Engines, Data Science, Tailwind CSS, Chatbots, Cron, Forms, Design, No-code Development

Experience

Custom eCommerce Store for Cult.fit

http://www.cult.fit/store

Built a custom in-house eCommerce store for the Indian fitness unicorn Cult.fit. I was the founding engineer of this vertical and led a team of five back- and two front-end engineers. I also contributed to the project in the back-end development and DevOps verticals as an individual contributor, helping create all the core and critical components of the eCommerce platform. I built this project in RoR and TypeScript and gained expertise in Spring Boot and most AWS services.

Near-real-time User-segmentation Platform

I built an in-house near-real-time user-segmentation platform to replace CleverTap and Segment.io at Cult.fit. The project quickly became the largest-scale service at Cult.fit and is being extracted as a SaaS tool today. I have designed proprietary algorithms for low-cost, high-latency ANSI SQL-compatible databases for bulk user-segment processing. The service helps target and convert high-intent users by automatically computed user segments based on user activity.

Co-Founder and CTO at Zecko

At Zecko, eCommerce is available on any app or website without the need to manage brand integrations, operations, or tech. Our one-line JavaScript code and adaptable eCommerce APIs allow you to embed commerce natively within your destination without the hassles of setting up eCommerce-focused teams.

Codebase Rewrite

https://www.1mg.com/

I contributed to rewriting the complete codebase of 1mgLabs from Python to RoR. It included designing a new system, rethinking business logic, identifying chunks of a large system, and planning the rewrite to achieve minimal overall downtime.

I also contributed to rewriting the complete codebase of Droplet, a subsidiary of 1mg, from PHP to RoR.

Software Engineering Work at Fastfox

http://fastfox.com/

I introduced a new repository that acts as a central library for all the repositories of Fastfox (used as a Node.js module).

I was part of a team of two that spent time researching, designing, and implementing a logging system to log all actions of a customer / related to the customer by internal employees using RabbitMQ and MongoDB.

The team also led the implementation of a dynamic panel along with back-end APIs for the actions of the requirement-gathering team. The questions asked were highly dynamic based on customers' previous answers (back end + front end).

Education

2013 - 2017

Bachelor's Degree in Information Technology

Indian Institute of Information Technology, Allahabad - Allahabad, India

Skills

Libraries/APIs

Node.js, REST APIs, jQuery, Shopify API, Sidekiq, OpenAPI, Typeform.io, React

Tools

NGINX, RSpec, Amazon CloudFront CDN, Amazon CloudWatch, Git, Zapier, cURL Command Line Tool, Front-end Build Tools, Wix, Postman, Amazon Elastic Container Registry (ECR), Cron, Bubble, GitLab, Canvas, RabbitMQ, Bower Front-end Dependency Manager

Languages

Java, Ruby, JavaScript, TypeScript, GraphQL, CSS, HTML, HTML5, CoffeeScript, SQL, Java 11, Bash Script, YAML, XML, Markdown, Python, C++, Python 3

Frameworks

Spring Boot, Ruby on Rails (RoR), Spring, Spring MVC, Swagger, Jest, Scrapy, Tailwind CSS, Spring Security, Flask, Django, Ruby on Rails 5, Express.js, Next.js

Paradigms

Microservices, Microservices Architecture, Serverless Architecture, Enterprise Application Architecture, Unit Testing, Event-driven Architecture, Lambda Architecture, Back-end Architecture, Responsive, DevOps

Platforms

Amazon Web Services (AWS), Shopify, Amazon EC2, AWS Lambda, Ubuntu, Linux, AWS Elastic Beanstalk, Java EE, Webflow, HubSpot, Docker

Storage

MySQL, Redis, PostgreSQL, JSON, Amazon S3 (AWS S3), Redis Cache, Relational Databases, Databases, Database Administration (DBA), Data Pipelines, MongoDB, Google Cloud

Other

Interviewing, Web Scraping, Scraping, Web Development, Full-stack, Back-office System Development, CTO, Architecture, APIs, Back-end, Technical Consulting, Headless Software, Cloud, Scalability, Third-party APIs, Security, Software Architecture, API Integration, Technical Writing, Payment APIs, Online Payments, Front-end, Technical Leadership, Software Design, Scalable Architecture, SDKs, Software Packaging, Documentation, Amazon RDS, Enterprise Architecture, Integration Testing, VM, GitOps, DevOps Engineer, Back-end Development, Roadmaps, Solution Architecture, Client-server Model, Data Analysis, IT Consulting, Startups, Distributed Systems, SaaS, eCommerce, Consulting, Pricing Consulting, Technical Architecture, Leadership, Low Latency, Multithreading, Minimum Viable Product (MVP), CI/CD Pipelines, Product Development, Estimations, Cloud Platforms, CRM APIs, Lambda Functions, API Connectors, Back-end Performance, Technical Documentation, Logistics, Analytics, Reports, IT Project Management, IT, Cloud Architecture, Ruby Gems, Writing & Editing, Front-end Development, Data Scraping, Large-scale Web Crawlers, Web Crawlers, Algorithms, Workflow, Dashboard Development, Integration, Responsiveness, Springbot, Data Engineering, Search Engines, Data Science, Chatbots, Forms, Design, No-code Development, Full-stack Development, UI Development, Artificial Intelligence (AI), Generative Pre-trained Transformers (GPT), WebSockets

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