Since its launch earlier this year, the Coretax system from the Directorate General of Taxes (DJP) has often been in the public spotlight. Its purpose is admirable: to unify the processes of registration, reporting, payment, and tax collection into a single integrated platform. However, in practice, many taxpayers have complained about various issues: login failures, unsynchronized data, and even sudden system crashes.
As a software engineer, I’d like to highlight some recurring technical issues. Not to assign blame, but to illustrate how a system of this scale can be made more stable, faster, and easier for everyone to use.
Table of Contents
The Most Common Issues
Based on reports and user experiences, the main problems include:
- Login failures – many users cannot log in even after resetting their passwords (though DJP claims fixes have been made).
- Validation & digital certificate errors – for example, failed facial recognition or certificates showing the wrong owner.
- Legacy data missing – past tax debts or historical records sometimes do not appear in the new system.
- Poor performance – during peak periods (such as near the SPT reporting deadline), the system feels sluggish or even goes down.
- Security & phishing risks – fake websites and scams imitating Coretax have surfaced.
These issues cause frustration. Yet from a technical standpoint, many of them especially performance issues can actually be addressed.
How Large-Scale Systems Should Work
A system like Coretax can be imagined as a digital highway. If there’s only one big lane, traffic will jam when thousands of cars enter at once. The solution is to create multiple lanes, place staff at each gate, and provide emergency routes in case of accidents.
In technical terms, here are some solutions:
1. Break the System into Smaller Modules (Microservices)
Instead of one giant system, Coretax could be split into modules: login, reporting, payments, historical data, etc. This way, if login fails, payment services can still function. The system becomes more flexible.
2. Add “Extra Lanes” During Peak Times
Coretax must be able to auto-scale: automatically add more servers when traffic spikes. It’s like opening more toll gates during holiday seasons to avoid queues.
3. Use Cache & CDN
Frequently accessed data (like taxpayer profiles or SPT status) should be cached so it doesn’t always pull from the main database. For static files (forms, images, scripts), a CDN ensures faster access across Indonesia.
4. Strengthen Authentication Systems
Login and certificates are the main entry points. They should not become single points of failure. Queuing systems or fallback mechanisms can ensure users still get access even if the main server is overloaded.
5. Monitoring & Automated Alerts
A system of this scale needs a dashboard to track application health: logins, error counts, response times. If errors spike, the technical team should get alerts immediately—before users vent on social media.
6. Enhance Security
Beyond technical fixes, phishing is a real threat. Educating users about official domains, ensuring encrypted connections (HTTPS), and strengthening cybersecurity must be top priorities.
Suggested Improvement Roadmap
Not everything has to be fixed overnight. Improvements can be rolled out in stages:
- Critical fixes: ensure stable login and reporting.
- Refactoring: break the system into smaller modules (if this takes too long, scalability first).
- Scalability: use cloud infrastructure, load balancers, and auto-scaling.
- Monitoring: implement real-time observability.
- Security: add DDoS protection, encryption, and public education.
- Feedback loop: gather user feedback, run stress tests regularly, and continuously iterate.
Closing Thoughts
Coretax is an ambitious and vital project for Indonesia. But a system of this scale cannot simply be built once and left alone. It needs constant improvement, testing, and optimization. With a more modular architecture, infrastructure that adapts automatically to demand, and robust security, Coretax has the potential to become a shining example of how technology can strengthen public services.
As a software engineer, my hope is simple: that Coretax will not just be seen as a “new tax system,” but will evolve into a service that is stable, transparent, and user-friendly for engineers, taxpayers, and the government alike.
