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deinsluck

Denis Lit

@deinsluck

Premium quality solutions with a strong focus on excellence and reliability

Kazakhstan
Russian, English
About me
Hi, I'm Denis, a Senior Fullstack Developer with 8+ years of commercial experience building backends, APIs, and automation systems that actually work under pressure. I specialize in Laravel, Python, and React — from clean REST APIs and Telegram/WhatsApp bots to WordPress customizations and AI integrations. Every project I deliver is well-structured, scalable, and built to last. I use modern AI tools daily to move faster without cutting corners — so you get quality work delivered on time. Let's turn your idea into a working product. Drop me a message!... Read more

Skills

d
deinsluck
Denis Lit
Offline • 
Average response time: 1 hour

See my services

WordPress
I will fix wordpress bugs and build custom wordpress website
From$80 / projectMore details
Rule Based Chatbots
I will develop a custom telegram bot for your business
From$385 / projectMore details

Portfolio

Work experience

Fiverr

Fiverr

6 yrs 5 mos

Team Lead / Senior Fullstack Developer

Dec 2023 - Present • 2 yrs 7 mos

High-load SaaS CRM/ERP, 100k+ concurrent users. Stack: Laravel, React, PostgreSQL, Redis, Docker, RabbitMQ. ● Led 6-engineer team; architected CRM/ERP platform from scratch — full-stack ownership (Laravel backend, React frontend). ● Integrated 10+ third-party services: banking APIs, payment gateways, telephony; built reusable abstraction layer. ● Cut page load 60 s → <1 s; reduced DB load 65%; boosted overall throughput 200%+.

Senior Fullstack Developer

Jan 2023 - May 2024 • 1 yr 4 mos

CRM platform with real-time analytics. Stack: Symfony, FastAPI, React, Vue.js, PostgreSQL, Redis, WebSockets. ● Built CRM/analytics modules on Symfony + Python/FastAPI; delivered real-time WebSocket chat and live dashboards. ● Improved API response time 40%, reduced SQL query time 50%, cut DB load with multi-layer Redis caching.

Fullstack Developer

Jul 2020 - Jan 2023 • 2 yrs 6 mos

High-load promotional platforms. Stack: Laravel, Drupal, Python, MySQL, Redis, Docker. ● Developed high-load promo platforms with payment and external API integrations. ● Sped up background job processing 70%; tuned for traffic spikes and peak-load stability.