Yobuma
My role: Backend development. Worked on the PHP/Laravel backend for an intercity bus booking application.
View live product · Google PlaySOFTWARE ENGINEERING / FROM DESIGN TO DELIVERY
From business requirements to reliable software.
I’m Cristian, a fullstack engineer with PHP/Laravel project experience and a backend background in financial and booking platforms. I build and improve applications, integrations and automation, with ownership of delivery, performance and security.
PHP / LARAVELSECURITY BY DESIGNAVAILABLE 20 HOURS / WEEK
ENGINEERING EXPERIENCE AT
Home CreditHybrid TechnologiesInnotech
RELEVANT PROJECT EXPERIENCE
Application development, backed by project work.
Airtrip · Hybrid Technologies
- Problem
- Real-time flight and hotel search and booking required integrations with multiple external providers.
- My work
- Built backend APIs and provider integrations, refactored legacy services and added centralised observability for production investigation.
- Result
- 25% improvement in API performance following legacy-service refactoring.
SaleApp · Home Credit Vietnam
- Problem
- Collect and distribute a high volume of leads accurately across multiple sales channels.
- My work
- Designed and built the lead collection and distribution platform, with responsibility across requirements, implementation, testing, release and monitoring.
- Scale
- Over 200,000 leads processed per day. The wider services supported sales operations for more than 40,000 daily active users.
Unifimoney · Innotech Vietnam
Built backend services for onboarding, account management and trading workflows on a multi-asset wealth platform. Implemented authentication and authorisation for financial-platform access, and integrated cryptocurrency trading APIs with an external exchange.
SECURITY / PERFORMANCE / DELIVERY
What I take responsibility for.
A working feature is one part of delivery. I also care about who can access it, how it behaves under load and what happens after release.
A requirement from the start.
Review access permissions, validate inputs, protect sensitive data and secrets, and consider the risks introduced by integrations. Security belongs in design, implementation and release review.
Measure. Improve. Verify.
Investigate slow requests, data access and workflow bottlenecks. Establish a baseline and compare the result under realistic conditions so improvements are supported by evidence.
Clear scope. Visible progress.
Agree on acceptance criteria, work in reviewable milestones and raise risks early. Include testing, deployment, recovery planning and handover in the delivery scope.
WHAT I BUILD
01 — 04Four areas of work. One approach: understand the business, build the right system, and follow through into production.
01Automation & AI workflows
SCALINGBuild n8n workflows connecting forms, CRM, email and team notifications. Use AI for classification, research summaries and information processing where it adds value.
Automation & AI workflows
SCALING
My role: Automation development at Scaling.
Scope of work
- Connect business tools into reliable automated workflows.
- Automate lead intake, CRM sync, email and reporting.
- Monitor workflow runs, handle failures and control when outbound messages are sent.
AutomationLead funnelsAI assistants
Visit website · scaling.vn 02Shopify & e-commerce
HANOSSDevelop Shopify websites and manage the app ecosystem. Adapt the storefront, features and integrations to the way the business actually works.
Shopify & e-commerce
HANOSS
My role: Shopify storefront development and app management.
Scope of work
- Build and customise Shopify storefronts.
- Install, configure and manage apps and plugins.
- Build custom features and connect store data to the tools the team uses.
ShopifyStorefrontsApp management
Visit website · hanoss.com 03Websites & fullstack development
UNIK HOUSEBuild websites from the interface to the backend. Connect a considered user experience with the data and administration behind it.
Websites & fullstack development
UNIK HOUSE
My role: Fullstack website development.
Scope of work
- Develop responsive interfaces for desktop and mobile.
- Build backend services, APIs and data integrations.
- Deploy websites, verify releases and troubleshoot production issues.
WebsitesFullstack development
Visit website · unikhouse.vn 04ERP & business workflows
INTERNAL SYSTEMBuild software for sales management, company operations and business processes. Turn real requirements into clear workflows, consistent data and appropriate access controls.
ERP & business workflows
INTERNAL SYSTEM
My role: Sales management and company workflow development.
Scope of work
- Develop features for sales and company operations.
- Implement workflows, permissions and system integrations.
- Connect sales, reporting and team operations in one workspace.
Business operationsCompany workflows
Internal systemOpen an area to see the scope of work.
SCALING / AUTOMATION & LEAD FUNNEL
From a new enquiry to a clear next step.
A lead funnel that connects intake, qualification and sales handoff. It is designed to reduce the time spent moving information between tools, so the team can focus on the right conversations.
LEAD QUALIFICATIONCAPTURE → QUALIFY → FOLLOW UP
- 01
Capture enquiries
Bring leads in from forms and campaigns.
- 02
Check the details
Validate submissions and keep records consistent.
- 03
Assess the fit
Prioritise leads against agreed business criteria.
- 04
Add useful context
Use AI to summarise company research for the team.
- 05
Keep one record
Avoid duplicates and keep lead information together.
- 06
Route the next step
Help the right person take action.
Ready for a closer look
Flag high-priority enquiries for a person to review before sales outreach.
Build the conversation
Identify leads that may benefit from a relevant case study or discovery call.
Stay useful over time
Identify leads suited to educational content and a longer follow-up cycle.
CONNECTED TO THE TEAM’S DAILY WORK
CRM updates · Team notifications · Confirmation emails
WEB / SELECTED WEBSITES
Selected websites, from storefront to fullstack.
VIEW FULL SIZE Shopify & the shopping experience
Storefront development, feature customisation and app management for a personalised gift store.
Visit website ↗VIEW FULL SIZE A furniture website, frontend to backend
Collection landing pages, responsive interfaces and the systems behind the website.
Visit website ↗ERP / DASHBOARD & COMPANY CALENDAR
A clearer view of the business and the team.
I build internal tools that bring sales operations and company workflows together. Two examples from the ERP interface, shown with demo data.
VIEW FULL SIZE Operations dashboard
A shared view of sales, orders and team activity, helping managers see what needs attention.
VIEW FULL SIZE Company calendar
Attendance, leave and work requests organised in one calendar for day-to-day team coordination.
About
Broad engineering experience. Grounded in the business problem.
I have 8+ years of experience in backend development, system design and performance optimisation. Working across backend and frontend lets me connect interfaces, business logic and data.
I work across existing codebases and new products, choosing an approach around the business need and the system already in place. I can work alongside an existing team or own a defined workstream, from investigation and implementation to release and follow-up.
Hanoi University of Science and Technology · Information Technology · 2015–2020
PROFESSIONAL EXPERIENCE
Home Credit Vietnam
06/2024 — PRESENTSoftware Engineer
SaleApp · Sales operations platform
Owned backend features from requirements through release and monitoring. Built lead collection and distribution services for multiple sales channels.
Hybrid Technologies
10/2022 — 05/2024Software Engineer
Airtrip · Flight and hotel booking platform
Built APIs integrating external flight and hotel providers for real-time search and booking. Refactored legacy services, improved test coverage and centralised production observability.
Innotech Vietnam
01/2018 — 09/2022Software Engineer
Unifimoney · Wealth management platform
Built backend services for onboarding, account management and trading workflows. Implemented authentication and authorisation, and integrated cryptocurrency trading APIs with an exchange.
HOW WE SHIP
01
Understand the system
Clarify the business goal, inspect the existing code and agree on scope, risks and acceptance criteria.
02
Deliver in clear steps
Build in reviewable milestones, validate changes in staging and run relevant tests. Share a weekly update covering progress, risks and next steps.
03
Release and follow through
Check backups and the rollback plan before release. Provide release notes, verify the live result and monitor for issues after handover.
What would you like to build?
Available for 20 hours per week. Share your product, existing system and the result you need. We can start with a clearly scoped feature, technical review or performance improvement.
[email protected]