Rupanjana
Mitra

Cofounder at Kokum Labs who builds software that holds up

I build backend systems that hold up in production: pricing engines, approval flows, payment reconciliation. I am cofounder at Kokum Labs, a fintech firm.

(the drawings are the best part, keep scrolling)

a house, some birds, a very large sun

what I do now

Kokum Labs

kokum labs

Payments infrastructure, for humans and for agents

I cofounded Kokum Labs because I want to go deep into fintech.

The first is merchant onboarding: getting verified by a payment gateway still means a document back-and-forth that stalls for weeks. We are building an agent that handles it. The second is agent pay. AI agents can now decide to buy something, but there are no rails for them to actually transact on. We are building those.

Merchant onboarding

An agent that removes the document back-and-forth in merchant verification for payment gateways.

Agent pay

Payment infrastructure that lets AI agents transact.

things I made

Selected work

Backend systems where being wrong is expensive. These show how I think about a problem, not just which tools I know.

Offer Generator

2026

Replaced spreadsheet-driven costing and offer creation at Encon with a real backend service. Pricing rules live in the system instead of in a workbook someone forgot to update, and every offer goes through the same validated path.

Cut offer turnaround by 70% and manual errors by 75%. In daily use by the commercial team.

  • Python
  • FastAPI
  • PostgreSQL

RFQ Tracker

2026

Tracks requests for quotation through the whole commercial pipeline, from intake and costing through to approval and response, so nothing stalls silently and everyone can see where a quote actually is.

Running in production at Encon.

  • Python
  • FastAPI
  • PostgreSQL

KDE Sheets UI features

2014

User-facing UI features for KDE Sheets, the spreadsheet application in the KDE suite. Built during Google Summer of Code, with feature design and code review by the upstream maintainers.

  • C++
  • Qt

OneBusAway web application

A web application for OneBusAway, the open-source real-time transit information system.

    who is behind all this

    About me

    I am a backend engineer. Most of what I have built lives out of sight: pricing engines, approval flows, payment reconciliation. It is the machinery underneath a business, where being wrong is expensive and being unpredictable is worse.

    My favourite kind of work is taking something error-prone and manual and making it deterministic. At Encon I replaced spreadsheet-driven costing with real systems, and watched offer turnaround drop by 70% and manual errors by 75%. I own the whole lifecycle: architecture, deployment, monitoring, and the 2am pages.

    In August 2026, I left Encon to cofound Kokum Labs. We are working on two problems in payments. The first is merchant onboarding, where an agent removes the document back-and-forth in merchant verification. The second is agent pay, the payment infrastructure AI agents need to transact.

    Between 2018 and 2025 I built and ran a tourism business: a portfolio of Airbnb properties and a walking tour agency. Years of hosting people is the reason I build the way I do now: sustainably, honestly, and with a lot of care for the humans on the other side of the system.

    Away from the terminal I read, box, play football, and wishlist Airbnbs. Right now I am reading Vijaya Maria.

    70%

    Faster offer turnaround

    75%

    Fewer manual errors

    2014

    Google Summer of Code

    B.Tech in Computer Science and Engineering

    National Institute of Technology Durgapur, India

    Aug 2011 to May 2015

    the gallery ↓

    home
    the big tree
    after rain
    for you

    every hat, so far ↓

    • Airbnb host500+ reviews, Airbnb + Google
    • Fitness coach
    • Software engineer
    a thing I like knowing

    Arabs who settled along the Konkan coast married local women, and their descendants became the Navayathis, a community of traders, and very good sailors.

    The Economic Times

    featured for resilience

    “What we did was to survive.”

    “Well, that is enough.”

    my favourite line

    what is in the pencil case

    Skills

    Languages

    • Java
    • Python
    • C++
    • SQL
    • JavaScript

    Frameworks

    • FastAPI
    • Spring Boot
    • Spring Security

    Systems

    • Distributed Systems
    • Concurrency
    • Fault Tolerance

    Tools

    • PostgreSQL
    • Redis
    • Docker
    • Git
    • GCP

    how I got here

    Experience

    1. Cofounder

      Aug 2026 to Present

      Kokum Labs · Panjim, Goa, India (remote)

      • Solving the merchant onboarding problem for payment gateways: building an agent that removes the document back-and-forth in merchant verification.
      • Solving agent pay: payment infrastructure for AI agents to transact.
    2. Senior Software Engineer, Backend & Systems

      Jan 2026 to Aug 2026

      Encon Thermal Engineering Pvt. Ltd. · Panjim, India

      • Designed and deployed the Offer Generator and RFQ Tracker, replacing spreadsheet-driven costing and offer workflows.
      • Reduced offer turnaround time by 70% and manual errors by 75%.
      • Owned system architecture, deployment, monitoring, and operational support.
      • Worked closely with business stakeholders to translate pricing and commercial requirements into system design.
    3. Founder, Tourism & Hospitality

      Aug 2018 to Dec 2025

      Airbnb portfolio & walking tour agency · Shantiniketan, India

      • Founded and ran a tourism business: a portfolio of Airbnb properties and a walking tour agency.
      • Hosted guests across multiple listings, earning 500+ reviews across Airbnb and Google.
      • Built and led the walking tour side end to end: itineraries, bookings, and guiding.
      • Featured in The Economic Times for resilience.
    4. Software Engineer

      Jan 2016 to Jul 2018

      BillDesk · Mumbai, India

      Offer in hand on graduating; the joining date at BillDesk was January 2016.

      • Developed Java and Spring backend services for internal payment systems.
      • Optimised PostgreSQL schemas for transactional correctness and reporting.
    5. Google Summer of Code Intern, KDE Sheets

      May 2014 to Sep 2014

      KDE · Remote

      • Implemented user-facing UI features for KDE Sheets as part of Google Summer of Code.
      • Collaborated with global open-source maintainers on feature design and code reviews.

    the bit where you say hello

    Tell me what you are building

    If you are building in payments, or working on agents that need to pay for things, I would like to hear about it. I answer within two business days. Email me, or get on a Google Meet with me.

    or get on a Google Meet with me

    Grab a slot

    thanks for scrolling all the way down