PParminder singh·4h agoPayment failed but money deducted: how idempotency keys stop double chargesThe app shows "Payment failed". A second later your phone gets an SMS: ₹2,000 debited. You tap Pay again. Now ₹4,000 is gone, and you still have no order. This post covers why this happens, the fixes5 min read·systemdesignwithparam.hashnode.dev
SSohail Khan·2h agoYour API Does Not Need More Logs. It Needs One Error Shape.Your API does not need more logs. It needs one error shape. A client I worked with kept breaking every time an endpoint failed. One error came back as plain text, the next as an HTML page, the next as4 min read·msohailkhandev.hashnode.dev
EEngage HRMS·4h agoNCP days in the EPF ECR: how field 10 works and the payroll bugs that miscount itA whole-number field that most payroll code fills from the wrong table8 min read·engagehrms.hashnode.dev
AAdam Jaber·8h agoYour LLM Limits Were Tuned in English: A Multilingual Token Budget Auditmax_tokens, history windows, rate limits, input caps and RAG chunks all shrink for Hindi, Tamil and Arabic users. Here's how to measure and fix it.10 min read·simplyexplained.hashnode.dev
GGowtham Muthuvel·8h agoJWT + Role-Based Access in Spring Security: Refresh Tokens Without the FootgunsRotation with reuse detection, ROLE_ vs SCOPE_ mapping, and the permitAll() trap, all tested on Spring Boot 4.1.2. Replaying an old refresh token revoked 2 tokens and killed the session.20 min read·gowthammuthuvel.hashnode.dev
MMuhammad Ali Qamar·20h agoAgent infrastructure is four bolted-on layers. None of them enforce.Libraries request. Runtimes enforce. The agent stack skipped that layer entirely.6 min read·devlogix.hashnode.dev
KKrrish Kumar·23h agoBuilding a distributed tokens-per-minute limiter for LLM APIs with one Redis Lua scriptToken buckets, reserve-and-settle leases, crash-safe concurrency slots, and why a 429 isn't always a rate limit7 min read·quietkernel.hashnode.dev
AAkshita Gupta·1d agoThe API Wasn't Slow: Finding a 2-Minute Delay in the Delivery PathThe API requests took 2+ minutes. How Nginx timing logs and testing from multiple places revealed the delivery path bottleneck.6 min read·codeincontextbyag.hashnode.dev27ORA
KKartik Budhlakoti·1d agoThe Project Behind These Posts: Medical Integrity SystemHow I built a FastAPI learning project with patient access rules, file integrity checks, automated tests and Docker deployment—and what went wrong.9 min read·kartikbudhlakoti.hashnode.dev13A
KKrishnam Murarka·1d agoAn audit log that says PUT /v2/object 200 won't help an investigationA request log can tell you that PUT /v2/object returned 200 at 14:03:07. It can't tell you who approved the refund, who changed a supplier's bank account, or whether the person clicking was an admin a4 min read·edilec-engineering.hashnode.dev11A
