Map the work
Sit with the people who do the job and write down the real flow.
--:--:-- BST · System online
ShishirKumar Das
Backend engineer with 3+ years building high-performance, scalable enterprise systems in Java and Spring Boot. I work across REST APIs, real-time data, payment integrations, intelligent automation, and fintech workflows, and I care about blockchain, AI agents, and distributed systems that hold up in production.
01 // CONSTELLATION
Projects
Logo on the left, details beside it
Featured
Public repositories
SB-IBMS
Shuvo Bangla integrated business system
The SB Group platform I work on at NJBL. One Spring Boot service and a Next.js console cover malls, retail, payroll, commissions, and the storefront. Java 17, JWT, Hibernate, and bKash sit under the modules below.
Technical expertise
Java 17Spring Boot 3JWT / RBACHibernate / JPAPostgreSQLNext.jsTypeScriptbKashTwilioExcel pipelines
Sectors
Shopping mall management
- Customer registrationRegister a new mall customer
- Customer dataView and manage mall customers
- Product repositoryAdd and manage products
- Reward cardsLoyalty cards for mall customers
- Payments historyTransactions across mall customers
- Analytics and reportsSales and performance
- Backup and restoreExcel for products, customers, sales, and cards
DEPLOY // SKYCALL ON CONTABO
Production pipelines
SB Group, RECS, Joggota, and SCOFS run on the SkyCall Contabo server. Coolify builds each Docker Compose stack from Git. Joggota is the pipeline with GitHub Actions in front of that deploy. RECS and SB Group also keep a separate Render path.
RECS API · SB Group
CI / CD
Contabo
SkyCall’s production server. Coolify runs here and hosts the SB Group, RECS, Joggota, and SCOFS stacks.
Coolify on Contabo
Git
Coolify
Docker
Contabo- 01One VPSContabo is the machine. The four products share it through Coolify, not through open host ports.
- 02Coolify on the boxCoolify is the control panel: domains, env, builds, and restarts.
- 03Private networkPostgres and the Spring APIs stay on the Docker network. Only the public site is given a domain.
- 04LogsEach container keeps rotated json-file logs, 10 MB by three files.
02 // STUDIO
SkyCall Soft
Software team · Startup
SkyCall Soft is the software development team I established, and the startup I am building into a software company. The team designs, builds, and supports operational systems, then stays on to train people and extend the software after launch.
What the team builds
Corporate operationsHospitalsHotelsE-commerceInsurancePropertyTradingUtilitiesCall centersStartup products
Design the system
Agree the screens, the data, and who is allowed to change it.
Ship in slices
Review working software as it lands, not in one final reveal.
Support it
Train the operators, then add the next module when the work grows.
03 // SIGNAL
About
3+ years in production
I design the services behind business operations: authenticated APIs, payment rails, cashback engines, and the schedulers that keep market and weather data honest. The work spans NJBL in Dhaka and a remote seat at Quantsys, building for teams that need the system to stay up.
01
Enterprise platforms
Microservices for retail, housing, and manufacturing. Customer master data, inventory, CRM, reporting, and role-based access on Spring Boot.
02
Payments and cashback
bKash gateway integration, cashback engines, disbursement sheets, reconciliation, and the financial workflows that sit behind them.
03
Live data systems
Schedulers, real-time extraction, electricity-market and weather data, Grafana monitoring, and AI-assisted backoffice jobs.
04 // RECORD
Work
January 2026 — Present
Dhaka
NJBL (SB Group)
Software Developer
- Designed and developed scalable microservices for retail, housing, and manufacturing domains using Java and Spring Boot.
- Built a large-scale platform managing customer master data, cashback systems, payments, and advanced reporting.
- Implemented JWT authentication and RBAC for secure, role-based enterprise access control.
- Integrated the bKash payment gateway, Twilio, and automated Excel-based reporting and disbursement pipelines.
- Optimized database schemas with Hibernate/JPA and managed the API lifecycle from development through production.
February 2023 — November 2025
Remote
Quantsys (USA)
Junior Java Developer
- Developed and maintained backend services for electricity market data platforms and real-time weather data systems.
- Designed schedulers for real-time data extraction, job execution, and automated workflows.
- Configured and supported AI-powered jobs and optimization processes on the Backoffice & Optimizer team.
- Built Grafana monitoring dashboards for system performance and data accuracy.
- Handled application configuration, deployment pipelines, technical documentation, and production releases.
- Worked with cross-functional teams on data validation and business requirement alignment.
05 // ARSENAL
Stack
Backend
Spring BootREST APIsMicroservicesSpring SecurityJWTOOPMVCMaven
06 // LOG
Record
Education
B.Sc. in Computer Science (Honors)
Brac University, Dhaka, Bangladesh
January 2019 — December 2022
- E-Game Development Instructor, RS Activity (2022 — present)
- Assistant Director, BRAC University Computer Club (Panel 2021–22)
Notre Dame College, Mymensingh
Mymensingh, Bangladesh
Courses
Agile Project Management — IBM- Introduction to Agile Development — IBM, July 2026
PHP with Laravel Framework — BITM Bangladesh
Cross Platform Game Development — ICT Ministry
Programming for Everybody (Python) — University of Michigan
Technical Support Fundamentals — Google
Honors
- 1st prize, wall magazine. Notre Dame Science Club · 1 September 2017 · Higgs boson feature
- Regional champion. Bangladesh Biology Olympiad
- Best speaker. Inter-college debate, Notre Dame Debating Club
Languages
BengaliNative
EnglishProfessional
HindiElementary
GermanElementary
JapaneseElementary
“I had the pleasure of working with Shishir when he was the Junior Developer at Quantsys. He was highly collaborative and demonstrated strong commitment as the team worked to improve development processes, and increase the overall reliability and capabilities of the software.”
“Shishir Kumar Das, A Java Developer, works at Quantsys. I and he are working in the same team. He is specially a configuration and documentation expert.”