Hi, I'm Hitesh Rana.

I build backend systems and developer tools, mostly in Go. Currently at Mercari, working on fraud and risk systems.

I'm interested in distributed systems, database internals, and making software easier to operate. Outside work, I tend to build things around scheduling, messaging, and the tools I wish I had.

Things I've built

  • chronoverse

    A distributed job scheduler and orchestrator for your own infrastructure. Built around durable execution and failure recovery.

  • jsonlogic2sql

    A JsonLogic-to-SQL transpiler supporting BigQuery, Spanner, PostgreSQL, DuckDB, and ClickHouse.

  • mq

    A pull-based gRPC message broker with batched reads, write-ahead logging, and consumer-controlled backpressure.

  • sourcecollector

    A small CLI that bundles source files into one text file to share codebase context with AI tools.

  • soundscripter

    Automates audio and video transcription through a distributed workflow.

More on GitHub

Work, so far

Mercari

  1. Software Engineer II

    Dec 2025 - present

    Bengaluru, India

    • Worked on the production fraud and risk rule engine at peak traffic of 10,000 payments and 1.5 million rule evaluations per minute. Implemented dynamic JsonLogic evaluation, on-demand feature fetching, dry runs, and explainable decisions.
    • Expanded the engine to multi-tenant item-risk detection, supporting 1,000 listings and up to 2 million category-filtered rule evaluations per minute.
    • Built jsonlogic2sql, now used in production for historical rule simulation in BigQuery, reducing pre-release validation effort by 80%.
    • Built scheduled Dataflow ETL and BigQuery jobs for risk data pipelines, supporting online decisions and offline analytics alongside Flink and Cloud Spanner.
    • Delivered real-time Rule Analytics across 200+ active rules. Established POS terminal data as a warehouse source of truth, eliminating duplicate data handling across 5+ services.

  2. Software Engineer I

    Oct 2024 - Nov 2025

    Tokyo, Japan

    • Architected high-volume asynchronous order-cancellation processing, cutting latency by 40%, preventing duplicate operations, and saving ¥7.4 million per month through improved fraud detection.
    • Optimized a high-traffic microservice with caching, reducing database query load by 85% and saving $40,000 per month in cloud infrastructure costs.
    • Owned an internal real-time abuse risk scoring service from development through delivery, maintaining p99 latency under 100 ms. Automated investigation workflows, saving analysts up to 5 minutes per case.
    • Consolidated and decommissioned anti-fraud rules in Flink deployments, reducing infrastructure costs by 30% while improving reliability.

  3. Software Engineer Intern

    Feb - Apr 2024

    Tokyo, Japan

    • Migrated legacy Spinnaker pipelines to GitOps with Argo CD, Flux, and Tekton, reducing deployment time by 40% and accelerating feature delivery across teams.
    • Built gRPC-based synchronization to update stale task statuses across distributed services, improving data consistency and reducing process disruptions by 75%.