Istanbul, Turkey

Bilgesu Çakır

Software Development Engineer. I build backend systems by day — currently at Hepsiburada, and spend my off hours shipping small side projects, crocheting, and hunting down the next film to watch.

bilgesucakir@gmail.com bilgesucakir bilgesucakir a_crocheters_diary

Education

Where it started

B.S. Computer Science & Engineering

Sabancı University · Graduated June 2023 · GPA 3.01/4.00

75% scholarship — ranked in the top 2,500 nationally in the YKS university entrance exam
High Honour certificate ×2 terms, Honour certificate ×2 terms

Coursework that stuck

AlgorithmsData StructuresOperating Systems Computer NetworksComputer & Network SecurityDatabase Systems Software EngineeringMachine LearningArtificial Intelligence Mobile App Development

Experience

Where I've worked

Software Development Engineer

Hepsiburada · Aug 2026 - Current

Backend engineer on Customer Care — working on the core product agents use to resolve issues of sellers and customers
Built and maintained Java/Spring Boot microservices backed by PostgreSQL, using Kafka for async event-driven communication alongside REST APIs for synchronous calls between services
Used Docker for containerization, OpenSearch for logging and search, and BigQuery/SQL for data-side analysis
Owned features end-to-end — picked up tasks, fixed bugs, and handled database-level operations directly
Building domain experience in large-scale e-commerce

Software Development Engineer

Amadeus, Istanbul · Feb 2024 – Jun 2026

Associate Software Development Engineer · Jul 2025 – Jun 2026

Junior Software Development Engineer · Feb 2024 – Jun 2025

Worked in the Order Management System under Nevio, building one unified order per traveller per IATA's One Order standard
Covered end-to-end travel processes — flights to hospitality — working with airlines like Finnair, Air France-KLM, and Saudia
Built event-driven, service-oriented Java microservices (Spring, Quarkus, Maven) on Kubernetes/OpenShift
Wrote unit and integration tests with Quarkus + JUnit; diagnosed and fixed defects in mission-critical distributed systems handling live airline traffic
Proposed and led internal projects to streamline the department's dev process
1st place, internal security/privacy bug bounty · 2nd place, Community Impact Hackathon (accessibility app, Flutter + Java)

Long Term Intern

Vodafone, Istanbul · Feb 2023 – Jul 2023

Part of the Payment Solutions team within Core IT, building and maintaining backend features with Java and Spring Boot
Gained first hands-on agile experience — sprint rituals, planning, and team collaboration

Information Systems Intern

Oyak-Renault, Bursa · Jul 2022 – Sep 2022

Joined the Information Systems department as part of the Orville Summer '22 programme, gaining first-hand experience with agile development practices
Designed and built a task management web app from scratch using Angular, Node.js, MongoDB
Took part in Orville Spark, a reverse mentorship programme connecting managers with younger colleagues

Learning Assistant

Sabancı University · Oct 2021 – Jun 2022

Supported instructors on CS201, Introduction to Computing
Helped students with course concepts and ran office hours, hands-on with C++

Graduation project

A year on one problem

Privacy-preserving MQTT messaging

Sabancı University · Sep 2022 – Jun 2023

MQTT is the messaging protocol half the IoT world runs on, and it leaks more than people assume. Working in a pair, we picked apart the protocol's weaknesses and designed three schemes to close them — covering confidentiality, authentication, authorisation, integrity and user privacy.

We then implemented all three across the server and client modules: ephemeral Diffie–Hellman for key exchange, authenticated encryption with AES, HMAC signatures and salting.

PythonMQTTDiffie–Hellman X.509AESHMACTopic hashing

Project report PDF · 120 pages Client Broker

Side projects

What I build for fun

What We'll Watch Tonight

Spring Boot · Vue · Jsoup — shipped

Compares 2–4 people's Letterboxd watchlists and returns the films everyone already wants to see, linking straight back to each film's page.

Live site Code on GitHub

veni-vidi-emi

Spring Boot · Vue · Leaflet — early stage

"I came, I saw, I bought" — a map-based aggregator pulling secondhand listings from Sahibinden, Dolap and others, plotted by area.

Code on GitHub

stitch-grapher

Java · Spring Boot · Treejs — shipped

Parses text crochet patterns — repeats, increases, decreases, magic rings — into a stitch connectivity graph, then lays it out as a 2D or 3D visualization.

Live site Code on GitHub

stitch-modeller

Java — concept stage

stitch-grapher's planned sequel: a comprehensive 3D modeller that takes the connectivity graph as input and renders the piece in three dimensions.

Code on GitHub

account-singularity

TypeScript extension — in progress

One master identity for signing up everywhere else, backed by an encrypted vault.

Code on GitHub

Jetlag Reset

Concept stage

Reads flight details from your calendar and builds a sleep, rest and meal-timing plan around the trip.

Code on GitHub

Shaker

Spring Boot · Vue 3 · MongoDB — early stage

A cocktail app: recipes, guidelines, a personal diary, sociallizing and events

Code on GitHub

Wingmark

Java · Spring Boot · Swift — in progress

A personal bird-logging iOS app. Log a sighting with photo, species, life stage, gender, location and notes, browse past logs on a map, look species up in a guide with photos and live call/song recordings, and earn badges along the way. Personal-only for now — every user sees just their own logs.

iOS app Backend

Tools