https://kubaik.github.io Practical backend engineering, AI tooling, and developer career advice by Kubai Kevin — a software developer with 10+ years building production systems in fintech and AI. en-us Thu, 12 Nov 2026 19:45:27 +0000 https://kubaik.github.io/structured-logging-searchable-at-scale/ Why free-text logs get slow and expensive at scale, and how a stable schema, shared logger, and value-based retention fix both problems. Thu, 12 Nov 2026 19:42:54 +0000 https://kubaik.github.io/structured-logging-searchable-at-scale/ https://kubaik.github.io/7-adr-traps-that-cause-stale-decisions/ How architecture decision records go stale: template bloat, drifting status fields, hidden storage, broken numbering, missing context, no workflow trigger, no review. Thu, 12 Nov 2026 06:24:11 +0000 https://kubaik.github.io/7-adr-traps-that-cause-stale-decisions/ https://kubaik.github.io/model-evals-the-gaps-that-let-drift-slip-through/ Aggregate eval scores hide subtle model drift. Learn per-example diffing, slice reporting, pinned baselines, and a minimal CI gate that catches behavior changes. Wed, 11 Nov 2026 19:26:17 +0000 https://kubaik.github.io/model-evals-the-gaps-that-let-drift-slip-through/ https://kubaik.github.io/canary-rollbacks-automate-the-decision-not-the-deploy/ Design canary analysis that compares against a live baseline, guards on sample size, and avoids the false positives that erode trust in automation. Wed, 11 Nov 2026 05:19:28 +0000 https://kubaik.github.io/canary-rollbacks-automate-the-decision-not-the-deploy/ https://kubaik.github.io/open-source-contributions-the-credibility-trap/ Why merged pull requests often fail to persuade hiring teams, and how to choose projects and shape contributions that read as engineering judgment. Tue, 10 Nov 2026 19:29:06 +0000 https://kubaik.github.io/open-source-contributions-the-credibility-trap/ https://kubaik.github.io/saga-pattern-orchestration-vs-choreography-in-payments/ How payment sagas coordinate steps, why refunds are not charge reversals, and a decision framework for choosing orchestration or choreography. Tue, 10 Nov 2026 06:34:03 +0000 https://kubaik.github.io/saga-pattern-orchestration-vs-choreography-in-payments/ https://kubaik.github.io/waf-and-bot-management-what-they-miss/ WAFs and bot managers filter known-bad requests, not business logic. Map blind spots, tune rules safely, and add application-layer controls. Mon, 09 Nov 2026 22:06:13 +0000 https://kubaik.github.io/waf-and-bot-management-what-they-miss/ https://kubaik.github.io/fastapi-vs-django-vs-flask-api-picks-for-2026/ Compare FastAPI, Django, and Flask on concurrency, validation, ORM, auth, and operations, with a worked latency example and a 30-minute check. Mon, 09 Nov 2026 05:20:45 +0000 https://kubaik.github.io/fastapi-vs-django-vs-flask-api-picks-for-2026/ https://kubaik.github.io/queueing-theory-for-backend-capacity/ Why doubling traffic can quadruple tail latency, how to model each constrained resource as a queue, and how to measure utilisation before you hit the cliff. Sun, 08 Nov 2026 17:48:03 +0000 https://kubaik.github.io/queueing-theory-for-backend-capacity/ https://kubaik.github.io/pagination-for-large-datasets-offset-vs-cursor/ How offset and keyset pagination behave on large datasets, where each fails, and how to ship signed cursors that stay correct under writes. Sun, 08 Nov 2026 05:08:16 +0000 https://kubaik.github.io/pagination-for-large-datasets-offset-vs-cursor/ https://kubaik.github.io/k6-vs-locust-traffic-models-that-lie/ Why closed-loop load tests under-report latency, how to build open-loop traffic models in k6 and Locust, and how to read the results without fooling yourself. Sat, 07 Nov 2026 17:38:37 +0000 https://kubaik.github.io/k6-vs-locust-traffic-models-that-lie/ https://kubaik.github.io/redis-vs-valkey-vs-dragonfly-which-in-memory-store/ A mechanism-first guide to picking Redis, Valkey or Dragonfly: fork history, single-thread limits, expiry semantics, migration tests and metrics. Sat, 07 Nov 2026 05:14:51 +0000 https://kubaik.github.io/redis-vs-valkey-vs-dragonfly-which-in-memory-store/ https://kubaik.github.io/ussdsms-fallback-the-session-trap/ Why USSD sessions and SMS receipts mislead fallback designs, and how to make the ledger the source of truth with idempotent state transitions. Fri, 06 Nov 2026 19:03:57 +0000 https://kubaik.github.io/ussdsms-fallback-the-session-trap/ https://kubaik.github.io/envelope-encryption-with-cloud-kms-key-rotation-traps/ How envelope encryption with cloud KMS breaks during key rotation, why wrapped data keys and key IDs must travel with ciphertext, and how to test it. Fri, 06 Nov 2026 05:44:18 +0000 https://kubaik.github.io/envelope-encryption-with-cloud-kms-key-rotation-traps/ https://kubaik.github.io/7-async-practices-that-cut-meeting-load/ Seven async practices that replace meetings rather than relocate them, with failure modes, prioritization guidance, and how to measure whether they work. Thu, 05 Nov 2026 19:43:18 +0000 https://kubaik.github.io/7-async-practices-that-cut-meeting-load/ https://kubaik.github.io/audit-trails-for-ai-agents-what-breaks-first/ Design append-only decision records for AI agents: write-ahead ordering, policy snapshots, idempotency keys, and reconstruction drills that expose gaps. Thu, 05 Nov 2026 05:48:30 +0000 https://kubaik.github.io/audit-trails-for-ai-agents-what-breaks-first/ https://kubaik.github.io/papss-and-mobile-money-where-integration-breaks/ Why cross-border PAPSS and mobile money integrations break: hold-and-resolve state machines, identifier resolution, and pending-set reconciliation. Wed, 04 Nov 2026 19:33:02 +0000 https://kubaik.github.io/papss-and-mobile-money-where-integration-breaks/ https://kubaik.github.io/technical-debt-defend-priorities-to-stakeholders/ A framework that turns technical debt into cost, risk, and timing arguments stakeholders can act on, with scoring, cost-of-delay arithmetic, and capacity rules. Wed, 04 Nov 2026 05:27:38 +0000 https://kubaik.github.io/technical-debt-defend-priorities-to-stakeholders/ https://kubaik.github.io/bm25-vs-dense-embeddings-hybrid-search-reality/ How BM25 and dense retrieval fail differently, why score fusion is not free, and how to choose RRF, weighted fusion, or a cascade for your corpus. Tue, 03 Nov 2026 19:21:26 +0000 https://kubaik.github.io/bm25-vs-dense-embeddings-hybrid-search-reality/ https://kubaik.github.io/sqlalchemy-vs-asyncpg-pooling-in-async-services/ How SQLAlchemy's async engine and asyncpg's pool actually relate, how to size pools against Postgres max_connections, and the failure modes that cause timeouts. Tue, 03 Nov 2026 05:54:22 +0000 https://kubaik.github.io/sqlalchemy-vs-asyncpg-pooling-in-async-services/