BUILD LOGS • FIELD NOTES • ARCHITECTURAL DECISIONS
ENGINEERING NOTES
First-person build logs, real architectural mistakes, and technical post-mortems from production Go and Flutter systems.
TOPIC:
SYSTEM// 2026
3 min read
How I cut JVM startup from 26s to 5s
Why cold JVM container startup was stalling judge execution in Code Runner, and how pre-warmed caching brought it down.
#Golang#Java#Kubernetes#Optimization
Structured technical outline. Points marked with [TODO] require confirmed benchmark numbers before publishing.
§ 01The Bottleneck: 26-Second Cold Starts
- ▹Running single Java code submissions in isolated containers had unacceptable latency.
- ▹[TODO: re-run benchmark harness and confirm exact JVM startup figure and memory footprint before fix].
- ▹Cold container initialization combined with JVM bytecode verification and JIT warmup.
§ 02The Architectural Decision
- ▹Evaluated persistent daemon JVMs vs ephemeral worker pools.
- ▹Chose Go-managed pre-warmed execution worker pools with memory limits.
- ▹[TODO: add memory overhead metrics for pre-warmed idle worker pool].
§ 03What I Got Wrong
- ▹Initially attempted aggressive class-sharing caches that caused classloader collisions between consecutive user submissions.
- ▹Settled on ephemeral sandboxes reset between executions with warm runtime baselines.
SYSTEM// 2026
4 min read
Running untrusted code in Kubernetes pods
Hardening multi-language execution with Amazon EKS pods, cgroups limits, wall-time timeouts, and live WebSockets.
#Kubernetes#Amazon EKS#Golang#Security
APP// 2026
3 min read
Why SecuChat keeps keys on the device
Architectural reasons for implementing zero-trust ECDH asymmetric key exchange over server-mediated sessions in Flutter.
#Flutter#Cryptography#ECDH#Google Play