Supported a payment service handling 7,200 req/min sustained (peaks 10–11k/min); eliminated full collection scans on multi-million-record MongoDB collections via targeted indexing.
Designed a live, zero-downtime pipeline to backfill HMAC hashes onto millions of tokenization records — 3-stage read/hash/write over buffered channels with randomized-window pagination and rate limiting.
Redesigned SNS transaction notifications from blocking calls into a two-tier async queue (in-memory + MongoDB), removing a complex circuit breaker and eliminating notification loss via deduplication.
Built secure, encrypted file transfer for ACH transactions between banking partners, plus a recovery workflow for failed ACH files via S3.
Enhanced the internal admin panel for transaction oversight, merchant management and payment operations; fixed critical ACH response-file parsing issues.
GoNode.jsMongoDBgRPCAWSJenkinsSplunk
08/2022 — 06/2024 Tokyo, Japan · Contract
Backend Engineer
Zeals Co. Ltd.
Built from scratch multiple services delivering notifications across messaging platforms to over a million end-users in minutes.
Cut system resource usage by ~50% while making processing significantly faster.
Developed shared libraries across teams and worked with frontend developers to integrate user-facing features with server-side logic.
GoMongoDBRedisBigQueryPub/SubGCPKubernetes
02/2021 — 07/2022 Tashkent, UZ
Software Engineer
Udevs LLC
Built an attendance management system end-to-end — React admin panel and Go backend with event-driven architecture on Kafka.
Automated salary calculation from attendance with penalties for lateness, plus attendance and salary reporting in PostgreSQL.
Optimized SMS and notification delivery for a delivery/order management product; optimized reporting queries over 2M+ rows.
GoReactVueNode.jsPostgreSQLKafkagRPC
10/2019 — 01/2021 Tashkent, UZ
Software Engineer
Online Service Group
Built from scratch an HRM system and a real-time online learning platform for the judges of the Republic of Uzbekistan, with live chat.
Created an interactive dashboard with an SVG map of Uzbekistan displaying data for every region.