Anshul BisenEngineering leader, builder, and tinkerer.https://anshulbisen.com/The portfolio is the proof. Ship your work or it did not happen.https://anshulbisen.com/blog/the-portfolio-is-the-proof-ship-your-work/https://anshulbisen.com/blog/the-portfolio-is-the-proof-ship-your-work/Not resumes. Not endorsements. Not interview performance. The code you ship, the systems you build, the writing you publish. Ship it or it did not happen.Sun, 12 Apr 2026 00:00:00 GMTWhat I got wrong in my first year as Head of Engineering and what I would do differentlyhttps://anshulbisen.com/blog/what-i-got-wrong-first-year-head-of-engineering/https://anshulbisen.com/blog/what-i-got-wrong-first-year-head-of-engineering/Over-hiring before culture. Saying yes to everything. Underinvesting in developer experience. Staying hands-on too long. The common thread was not trusting the team.Sun, 05 Apr 2026 00:00:00 GMTThe Cloudflare container platform changes what I would self-hosthttps://anshulbisen.com/blog/cloudflare-container-platform-changes-self-hosting/https://anshulbisen.com/blog/cloudflare-container-platform-changes-self-hosting/Edge containers win for stateless batch jobs and lightweight APIs. Self-hosting still wins for stateful services and observability. The line is shifting faster than expected.Sun, 29 Mar 2026 00:00:00 GMTWhy every fintech startup eventually builds its own ledgerhttps://anshulbisen.com/blog/every-fintech-startup-eventually-builds-own-ledger/https://anshulbisen.com/blog/every-fintech-startup-eventually-builds-own-ledger/FinanceOps started with a third-party ledger. Within 18 months we built our own. Ledger semantics are too coupled to business rules for abstraction.Sun, 22 Mar 2026 00:00:00 GMTThe real job of a Head of Engineeringhttps://anshulbisen.com/blog/the-real-job-of-a-head-of-engineering/https://anshulbisen.com/blog/the-real-job-of-a-head-of-engineering/Make throughput predictable and quality sustainable. Not hero-shipping. Not writing the most code. Build a system that delivers without depending on any single person.Sun, 15 Mar 2026 00:00:00 GMTArchitecture debt is usually a decision-quality problem firsthttps://anshulbisen.com/blog/architecture-debt-is-usually-a-decision-quality-problem-first/https://anshulbisen.com/blog/architecture-debt-is-usually-a-decision-quality-problem-first/The worst architecture debt comes from low-quality decisions made with plenty of time. Improving decision quality reduces debt faster than refactoring sprints.Tue, 10 Mar 2026 00:00:00 GMTEngineering teams do not need more process. They need better defaults.https://anshulbisen.com/blog/engineering-teams-do-not-need-more-process-they-need-better-defaults/https://anshulbisen.com/blog/engineering-teams-do-not-need-more-process-they-need-better-defaults/Every incident triggers a new process proposal. The real fix is better CI pipelines, better templates, and better linters. Better defaults scale. More process does not.Thu, 05 Mar 2026 00:00:00 GMTHow I evaluate build-versus-buy decisions at a 50-person startuphttps://anshulbisen.com/blog/evaluate-build-versus-buy-50-person-startup/https://anshulbisen.com/blog/evaluate-build-versus-buy-50-person-startup/Build-versus-buy is not about cost. It is about where your team's attention goes. Build what differentiates. Buy the commodity.Sun, 01 Mar 2026 00:00:00 GMTWhat AI changes about engineering leadershiphttps://anshulbisen.com/blog/what-ai-changes-about-engineering-leadership/https://anshulbisen.com/blog/what-ai-changes-about-engineering-leadership/Code review matters more than code writing. Architectural taste matters more than implementation speed. Evaluating AI-generated code is the new critical skill.Sat, 28 Feb 2026 00:00:00 GMTStartup speed and enterprise readiness are not oppositeshttps://anshulbisen.com/blog/startup-speed-and-enterprise-readiness-are-not-opposites/https://anshulbisen.com/blog/startup-speed-and-enterprise-readiness-are-not-opposites/Audit logging, RBAC, and proper error handling actually accelerate delivery by eliminating rework. Enterprise readiness is a speed multiplier, not a speed tax.Fri, 20 Feb 2026 00:00:00 GMTOpus 4.6 has a million-token context window and I am still not sure what to do with ithttps://anshulbisen.com/blog/opus-4-6-million-token-context-not-sure-what-to-do/https://anshulbisen.com/blog/opus-4-6-million-token-context-not-sure-what-to-do/Feeding entire codebases into a single prompt for architecture review produced mixed results. The practical sweet spots are narrower than the capability suggests.Mon, 09 Feb 2026 00:00:00 GMTDrizzle ORM crossed 32K stars and I still think ORM choice barely mattershttps://anshulbisen.com/blog/drizzle-32k-stars-orm-choice-barely-matters/https://anshulbisen.com/blog/drizzle-32k-stars-orm-choice-barely-matters/Query patterns, migration discipline, and connection pooling matter far more than which ORM you choose. The ORM was never the bottleneck.Mon, 02 Feb 2026 00:00:00 GMTWhy I run my portfolio site on the same stack I use at workhttps://anshulbisen.com/blog/portfolio-site-same-stack-as-work/https://anshulbisen.com/blog/portfolio-site-same-stack-as-work/Next.js, Payload CMS, PostgreSQL, Cloudflare. Not laziness. Every problem solved on the portfolio feeds back into production expertise.Mon, 26 Jan 2026 00:00:00 GMTCross-functional alignment is not a meeting problem. It is an incentive problem.https://anshulbisen.com/blog/cross-functional-alignment-is-an-incentive-problem/https://anshulbisen.com/blog/cross-functional-alignment-is-an-incentive-problem/Restructuring OKRs so engineering, product, and sales shared a single top-line metric per quarter fixed what years of alignment meetings could not.Mon, 19 Jan 2026 00:00:00 GMTThe homelab Loki stack that monitors my production alertshttps://anshulbisen.com/blog/homelab-loki-stack-monitors-production-alerts/https://anshulbisen.com/blog/homelab-loki-stack-monitors-production-alerts/A Grafana/Loki/Tempo stack on homelab k3s aggregates logs from personal projects and FinanceOps production alerting. A personal observability stack makes you a better leader.Mon, 12 Jan 2026 00:00:00 GMTThe hardest conversation I had in 2025 was firing a senior engineer I had hiredhttps://anshulbisen.com/blog/hardest-conversation-2025-firing-senior-engineer/https://anshulbisen.com/blog/hardest-conversation-2025-firing-senior-engineer/He interviewed brilliantly but could not operate in a startup. Performance management is the most important and least taught leadership skill.Mon, 05 Jan 2026 00:00:00 GMTBuilding a fintech reconciliation engine that handles ten million transactions a dayhttps://anshulbisen.com/blog/fintech-reconciliation-engine-ten-million-transactions/https://anshulbisen.com/blog/fintech-reconciliation-engine-ten-million-transactions/PostgreSQL partitioned tables, Node.js worker pools, idempotent batch processing, and a custom diffing algorithm. Sub-minute reconciliation at ten million daily transactions.Mon, 22 Dec 2025 00:00:00 GMTHow I budget engineering time and why I give 20 percent to platform work non-negotiablyhttps://anshulbisen.com/blog/budget-engineering-time-20-percent-platform/https://anshulbisen.com/blog/budget-engineering-time-20-percent-platform/Twenty percent of every sprint goes to platform work. The compounding cost of deferring platform investment is measurable in incident frequency and developer velocity.Mon, 15 Dec 2025 00:00:00 GMTS3 Vectors at re:Invent made me reconsider our entire RAG architecturehttps://anshulbisen.com/blog/s3-vectors-reinvent-reconsider-rag-architecture/https://anshulbisen.com/blog/s3-vectors-reinvent-reconsider-rag-architecture/2 billion vectors per index at 90% cost reduction. Our pgvector pipeline still makes sense, but the calculus for startups without millisecond latency needs is changing.Mon, 08 Dec 2025 00:00:00 GMTOpus 4.5 is the first AI model I trust to refactor production code unsupervisedhttps://anshulbisen.com/blog/opus-4-5-first-ai-model-trust-refactor-production/https://anshulbisen.com/blog/opus-4-5-first-ai-model-trust-refactor-production/Claude Opus 4.5 refactored a 500-line TypeScript module, maintained all tests, and passed review without modification. The bottleneck has shifted from writing to reviewing.Mon, 01 Dec 2025 00:00:00 GMTWhen your SLOs and your sales team disagree, the SLOs losehttps://anshulbisen.com/blog/when-slos-and-sales-team-disagree/https://anshulbisen.com/blog/when-slos-and-sales-team-disagree/An enterprise prospect required 99.99% uptime. Our SLOs were 99.9%. Engineering leaders who refuse to engage with commercial reality get bypassed.Mon, 24 Nov 2025 00:00:00 GMTFifteen years of writing code and I still mass-delete my first drafthttps://anshulbisen.com/blog/fifteen-years-still-mass-delete-first-draft/https://anshulbisen.com/blog/fifteen-years-still-mass-delete-first-draft/The first draft reveals the problem's shape. The second draft solves it. Engineers who try to write perfect code on the first pass are optimizing for the wrong thing.Mon, 17 Nov 2025 00:00:00 GMTThe Prisma-to-Drizzle migration we almost did and why we stayed on Prismahttps://anshulbisen.com/blog/prisma-to-drizzle-migration-we-almost-did/https://anshulbisen.com/blog/prisma-to-drizzle-migration-we-almost-did/We built a prototype, benchmarked it, and stayed on Prisma because the migration cost exceeded the performance gain for our actual query patterns.Mon, 10 Nov 2025 00:00:00 GMTWhy your engineering strategy document is probably a wish list, not a strategyhttps://anshulbisen.com/blog/engineering-strategy-document-is-probably-a-wish-list/https://anshulbisen.com/blog/engineering-strategy-document-is-probably-a-wish-list/A strategy is a diagnosis, a guiding policy, and coherent actions. Everything else is a roadmap pretending to be a strategy.Mon, 03 Nov 2025 00:00:00 GMTArgoCD taught me that GitOps is about audit trails, not about githttps://anshulbisen.com/blog/argocd-gitops-is-about-audit-trails/https://anshulbisen.com/blog/argocd-gitops-is-about-audit-trails/After running ArgoCD in homelab and production for over a year, the real value is not deployment automation. It is the complete, immutable audit trail.Mon, 27 Oct 2025 00:00:00 GMTI mass-deleted our internal wiki and started over. Twice.https://anshulbisen.com/blog/mass-deleted-internal-wiki-started-over-twice/https://anshulbisen.com/blog/mass-deleted-internal-wiki-started-over-twice/The wiki grew to 400 pages that nobody read. The fix was not better organization. It was aggressive pruning and a decay policy.Mon, 20 Oct 2025 00:00:00 GMTManaging up to a non-technical founder without losing your integrityhttps://anshulbisen.com/blog/managing-up-to-non-technical-founder/https://anshulbisen.com/blog/managing-up-to-non-technical-founder/Business-outcome framing for every technical decision. Risk quantified in dollars, not story points. Never say "technical debt" without a customer impact number.Mon, 13 Oct 2025 00:00:00 GMTUpgrading to Next.js 16 inside a Payload CMS monorepo was harder than expectedhttps://anshulbisen.com/blog/nextjs-16-payload-cms-monorepo-upgrade/https://anshulbisen.com/blog/nextjs-16-payload-cms-monorepo-upgrade/Cache Components and React Compiler 1.0 are compelling, but upgrading inside a CMS-coupled codebase surfaced dependency conflicts that deserved their own sprint.Mon, 06 Oct 2025 00:00:00 GMTWhat payment reconciliation systems teach you about distributed consistencyhttps://anshulbisen.com/blog/payment-reconciliation-teaches-distributed-consistency/https://anshulbisen.com/blog/payment-reconciliation-teaches-distributed-consistency/Eventual consistency in payment reconciliation is a business requirement, not a technical compromise. Idempotency keys and reconciliation windows replaced two-phase commits.Wed, 24 Sep 2025 00:00:00 GMTThe one-on-one framework I use after fifteen years of getting one-on-ones wronghttps://anshulbisen.com/blog/one-on-one-framework-after-fifteen-years/https://anshulbisen.com/blog/one-on-one-framework-after-fifteen-years/Three fixed sections: blockers with deadlines, career trajectory, and one question the report chooses. Structure creates safety without drift.Wed, 17 Sep 2025 00:00:00 GMTSonnet 4.5 replaced our first-pass code review and nobody complainedhttps://anshulbisen.com/blog/sonnet-4-5-replaced-first-pass-code-review/https://anshulbisen.com/blog/sonnet-4-5-replaced-first-pass-code-review/AI handles style violations and missing error handling. Human reviewers focus on architecture and business logic. Review turnaround dropped from 24 hours to 4.Wed, 10 Sep 2025 00:00:00 GMTRunning Kafka at startup scale is a decision you will regret exactly oncehttps://anshulbisen.com/blog/running-kafka-at-startup-scale-regret-exactly-once/https://anshulbisen.com/blog/running-kafka-at-startup-scale-regret-exactly-once/Kafka was justified for our payment event streaming. The operational burden in year two consumed a disproportionate share of platform bandwidth.Wed, 03 Sep 2025 00:00:00 GMTHow I use Grafana dashboards to run engineering meetings instead of slide deckshttps://anshulbisen.com/blog/grafana-dashboards-instead-of-slide-decks/https://anshulbisen.com/blog/grafana-dashboards-instead-of-slide-decks/Replacing weekly status slides with live Grafana dashboards eliminated performative reporting and forced teams to instrument what matters.Mon, 25 Aug 2025 00:00:00 GMTThe founder said ship in two weeks. I said no. Here is what happened.https://anshulbisen.com/blog/founder-said-ship-in-two-weeks-i-said-no/https://anshulbisen.com/blog/founder-said-ship-in-two-weeks-i-said-no/A major customer deal hinged on a feature in two weeks. I pushed for three. The extra week saved us on day four.Mon, 18 Aug 2025 00:00:00 GMTGPT-5 shipped and my team asked if we still need junior engineershttps://anshulbisen.com/blog/gpt-5-shipped-do-we-still-need-junior-engineers/https://anshulbisen.com/blog/gpt-5-shipped-do-we-still-need-junior-engineers/The answer is yes, but for reasons that forced us to articulate what junior engineers actually contribute beyond lines of code.Mon, 11 Aug 2025 00:00:00 GMTWhy I stopped asking candidates to whiteboard and started asking them to review pull requestshttps://anshulbisen.com/blog/stopped-whiteboard-interviews-started-pr-reviews/https://anshulbisen.com/blog/stopped-whiteboard-interviews-started-pr-reviews/Whiteboard coding measures performance under artificial stress. PR reviews measure what the job actually requires.Mon, 04 Aug 2025 00:00:00 GMTMy homelab staging cluster caught a production bug before CI didhttps://anshulbisen.com/blog/homelab-staging-caught-production-bug-before-ci/https://anshulbisen.com/blog/homelab-staging-caught-production-bug-before-ci/A memory leak only manifested under sustained 48-hour load. CI tests pass in seconds. The homelab k3s cluster caught what automated tests could not.Mon, 28 Jul 2025 00:00:00 GMTFintech compliance is not a checkbox. It is an architecture constraint.https://anshulbisen.com/blog/fintech-compliance-is-an-architecture-constraint/https://anshulbisen.com/blog/fintech-compliance-is-an-architecture-constraint/Compliance that lives in code survives team turnover. Compliance that lives in spreadsheets does not.Mon, 21 Jul 2025 00:00:00 GMTThe Kubernetes upgrade that taught me release engineering is a leadership problemhttps://anshulbisen.com/blog/kubernetes-upgrade-taught-me-release-engineering-is-leadership/https://anshulbisen.com/blog/kubernetes-upgrade-taught-me-release-engineering-is-leadership/A Kubernetes 1.34 upgrade stalled for six weeks not because of technical complexity, but because nobody owned the migration sequence.Mon, 14 Jul 2025 00:00:00 GMTTwo years in and I finally stopped rewriting the org chart every quarterhttps://anshulbisen.com/blog/stopped-rewriting-the-org-chart-every-quarter/https://anshulbisen.com/blog/stopped-rewriting-the-org-chart-every-quarter/Constant restructuring is a symptom of unclear ownership, not wrong structure. Org charts stabilize when decision rights are explicit.Mon, 07 Jul 2025 00:00:00 GMTEighteen months in: the five things I would tell myself on day one as Head of Engineering at a startuphttps://anshulbisen.com/blog/eighteen-months-five-things-day-one-head-of-engineering/https://anshulbisen.com/blog/eighteen-months-five-things-day-one-head-of-engineering/Delegate before you are ready. Learn compliance before it learns you. Your cofounder's priorities are not wrong, just different. Tech debt compounds faster than you think. And the hardest one: your job is not to write the best code.Mon, 30 Jun 2025 00:00:00 GMTKubernetes 1.33 and the features that finally made me stop questioning container orchestration for small teamshttps://anshulbisen.com/blog/kubernetes-1-33-stop-questioning-containers-small-teams/https://anshulbisen.com/blog/kubernetes-1-33-stop-questioning-containers-small-teams/Every six months someone says Kubernetes is overkill for a small team. Kubernetes 1.33 continued a trend of sane defaults and reduced overhead that invalidates that argument for teams deploying more than two services.Mon, 23 Jun 2025 00:00:00 GMTThe on-call rotation that was just me, and why I finally admitted that was not sustainablehttps://anshulbisen.com/blog/on-call-rotation-just-me-not-sustainable/https://anshulbisen.com/blog/on-call-rotation-just-me-not-sustainable/For 14 months I was the only person who got paged at 3 AM. The real reason was not team size. It was that I did not trust anyone else to handle production incidents.Thu, 19 Jun 2025 00:00:00 GMTBuilding Cloudflare Tunnel access to our homelab staging so the team stops saying "works on my machine"https://anshulbisen.com/blog/cloudflare-tunnel-homelab-staging-team-access/https://anshulbisen.com/blog/cloudflare-tunnel-homelab-staging-team-access/Our k3s staging cluster sat behind my home network. Cloudflare Tunnels gave the whole team stable HTTPS access without exposing my home IP or managing VPN credentials.Mon, 16 Jun 2025 00:00:00 GMTCross-functional friction is a feature, not a bug, if you build the right feedback loopshttps://anshulbisen.com/blog/cross-functional-friction-feature-not-bug/https://anshulbisen.com/blog/cross-functional-friction-feature-not-bug/For months I treated pushback from product, sales, and compliance as obstacles to velocity. The reframe: friction between teams is signal about misaligned priorities, and the right response is better feedback loops.Mon, 09 Jun 2025 00:00:00 GMTTypeScript strict mode migration: the six-month project I wish I had done in month onehttps://anshulbisen.com/blog/typescript-strict-mode-migration-wish-month-one/https://anshulbisen.com/blog/typescript-strict-mode-migration-wish-month-one/We started with TypeScript loose mode because "we will tighten it later." Eighteen months and 40,000 lines later, migrating to strict surfaced 847 errors, including three that affected financial calculations.Mon, 02 Jun 2025 00:00:00 GMTClaude Opus 4 and Sonnet 4: the week AI coding tools stopped being novelties and became infrastructurehttps://anshulbisen.com/blog/claude-opus-4-sonnet-4-ai-coding-infrastructure/https://anshulbisen.com/blog/claude-opus-4-sonnet-4-ai-coding-infrastructure/When Claude Opus 4 hit 72.5% on SWE-bench and solved a TypeScript generics issue that had stumped our team, the conversation shifted from "should we use AI" to "how do we integrate it."Mon, 26 May 2025 00:00:00 GMTFounder dynamics: when your technical opinion conflicts with the CEO's investor promisehttps://anshulbisen.com/blog/founder-dynamics-technical-opinion-vs-investor-promise/https://anshulbisen.com/blog/founder-dynamics-technical-opinion-vs-investor-promise/The CEO told investors we would launch a new vertical by Q3. I told the CEO we needed Q3 for infrastructure debt. We were both right, which made it worse.Mon, 12 May 2025 00:00:00 GMTGrafana, Loki, and Tempo: building an observability stack that a four-person team actually useshttps://anshulbisen.com/blog/grafana-loki-tempo-observability-four-person-team/https://anshulbisen.com/blog/grafana-loki-tempo-observability-four-person-team/Most observability guides assume a platform team. We do not have one. The hard part was not installation but building dashboards engineers actually check daily.Mon, 05 May 2025 00:00:00 GMTThe compliance audit that exposed every shortcut we took in our first yearhttps://anshulbisen.com/blog/compliance-audit-exposed-every-shortcut-first-year/https://anshulbisen.com/blog/compliance-audit-exposed-every-shortcut-first-year/Our first formal compliance audit surfaced 23 findings. Hardcoded keys, PII in logs, missing audit trails. None malicious, all "we will fix that later." The remediation sprint that followed.Mon, 28 Apr 2025 00:00:00 GMTOpenAI o3 and o4-mini: reasoning models are getting good enough to replace junior code reviewhttps://anshulbisen.com/blog/o3-o4-mini-reasoning-models-replace-junior-code-review/https://anshulbisen.com/blog/o3-o4-mini-reasoning-models-replace-junior-code-review/o3 drops 20% fewer major errors than o1, and o4-mini makes reasoning affordable for CI pipelines. A financial calculation rounding error caught by AI review that three humans missed.Mon, 21 Apr 2025 00:00:00 GMTWhy I stopped mass-applying "best practices" and started asking "best for what"https://anshulbisen.com/blog/stopped-best-practices-started-best-for-what/https://anshulbisen.com/blog/stopped-best-practices-started-best-for-what/Microservices, event sourcing, CQRS, DDD. I had been cargo-culting patterns from companies 100x our size. The question "who benefits from this complexity" changed my architectural decisions.Mon, 14 Apr 2025 00:00:00 GMTArgoCD and GitOps for a team of four: overkill or exactly righthttps://anshulbisen.com/blog/argocd-gitops-team-of-four-overkill-or-right/https://anshulbisen.com/blog/argocd-gitops-team-of-four-overkill-or-right/After three months of ArgoCD managing our k3s and production clusters, the deployment confidence, audit trail, and rollback speed paid for the setup cost within the first incident.Mon, 07 Apr 2025 00:00:00 GMTThe quarterly planning meeting that taught me product managers and engineers solve different problemshttps://anshulbisen.com/blog/quarterly-planning-product-engineers-different-problems/https://anshulbisen.com/blog/quarterly-planning-product-engineers-different-problems/I walked into Q2 planning with technical improvements. Product walked in with customer churn data. We talked past each other for two hours before building a framework to bridge both worldviews.Mon, 31 Mar 2025 00:00:00 GMTOur Kafka consumer lag crisis and why I stopped trusting "it works on my machine" for event-driven systemshttps://anshulbisen.com/blog/kafka-consumer-lag-crisis-event-driven-trust/https://anshulbisen.com/blog/kafka-consumer-lag-crisis-event-driven-trust/Consumer lag grew silently for two weeks because local dev processed events instantly while production dealt with partition rebalancing and back-pressure from a slow downstream service.Mon, 24 Mar 2025 00:00:00 GMTGoogle's $32B Wiz acquisition and what it signals about security as a first-class infrastructure concernhttps://anshulbisen.com/blog/google-wiz-acquisition-security-first-class-infra/https://anshulbisen.com/blog/google-wiz-acquisition-security-first-class-infra/Google paying $32B for a cloud security startup signals that security is no longer a checkbox but a competitive differentiator, especially in fintech where trust is the product.Mon, 17 Mar 2025 00:00:00 GMTLearning to delegate when every task feels faster to do yourselfhttps://anshulbisen.com/blog/learning-to-delegate-faster-to-do-yourself/https://anshulbisen.com/blog/learning-to-delegate-faster-to-do-yourself/For six months I was the bottleneck on every code review, architecture decision, and production deploy. Delegation felt slower because it was. The turning point was redefining my job.Mon, 10 Mar 2025 00:00:00 GMTPostgres connection pooling: the problem you do not know you have until you have 50 concurrent usershttps://anshulbisen.com/blog/postgres-connection-pooling-50-concurrent-users/https://anshulbisen.com/blog/postgres-connection-pooling-50-concurrent-users/Our Node.js API opened a new PostgreSQL connection per request. At 50 concurrent users we exhausted the connection limit and the whole system halted. PgBouncer fixed it.Mon, 03 Mar 2025 00:00:00 GMTWhen the sales team demos a feature that does not exist yet and engineering finds out from a prospecthttps://anshulbisen.com/blog/sales-demos-feature-that-does-not-exist/https://anshulbisen.com/blog/sales-demos-feature-that-does-not-exist/A prospect called asking for help configuring a feature our sales deck showed but engineering had never built. The fallout was not the scramble but the trust erosion between teams.Mon, 24 Feb 2025 00:00:00 GMTClaude 3.7 Sonnet's extended thinking and what it means for code review at a small teamhttps://anshulbisen.com/blog/claude-3-7-sonnet-extended-thinking-code-review/https://anshulbisen.com/blog/claude-3-7-sonnet-extended-thinking-code-review/Extended thinking mode changed how I approach code review on a team too small for dedicated reviewers. Step-by-step deliberation catches subtle type issues that fast-pass models miss.Mon, 17 Feb 2025 00:00:00 GMTThe tech debt spreadsheet that made my cofounder finally understand why we need a refactoring sprinthttps://anshulbisen.com/blog/tech-debt-spreadsheet-cofounder-refactoring-sprint/https://anshulbisen.com/blog/tech-debt-spreadsheet-cofounder-refactoring-sprint/Saying "we have tech debt" to a non-technical cofounder is meaningless. A spreadsheet mapping each debt item to customer-facing risk and remediation cost finally moved the conversation.Mon, 03 Feb 2025 00:00:00 GMTDeepSeek R1 and the moment I realized open-source AI would change how we build internal toolshttps://anshulbisen.com/blog/deepseek-r1-open-source-ai-internal-tools/https://anshulbisen.com/blog/deepseek-r1-open-source-ai-internal-tools/DeepSeek R1 shipped as a 671B open-source model matching GPT-4o benchmarks for under $6M training cost. Self-hostable reasoning models change the calculus for regulated fintech.Mon, 27 Jan 2025 00:00:00 GMTMigrating from REST to a hybrid REST/event architecture without stopping the trainhttps://anshulbisen.com/blog/rest-to-hybrid-event-architecture-without-stopping/https://anshulbisen.com/blog/rest-to-hybrid-event-architecture-without-stopping/Our reconciliation engine needed async event processing but API consumers expected synchronous responses. The strangler fig pattern applied to a fintech data pipeline.Mon, 20 Jan 2025 00:00:00 GMTI mass-rejected 200 resumes and hired the person who asked the best questions in the interviewhttps://anshulbisen.com/blog/mass-rejected-200-resumes-hired-best-questions/https://anshulbisen.com/blog/mass-rejected-200-resumes-hired-best-questions/Our first structured hiring round attracted 200+ applications. The person we hired had a weaker resume than a dozen others but asked questions that revealed deep systems thinking.Mon, 13 Jan 2025 00:00:00 GMTAWS re:Invent announcements that actually matter for a three-person fintech teamhttps://anshulbisen.com/blog/reinvent-2024-what-matters-three-person-fintech/https://anshulbisen.com/blog/reinvent-2024-what-matters-three-person-fintech/Aurora DSQL, S3 Tables, Amazon Nova. re:Invent 2024 dropped a firehose of announcements, but most solve problems we will not have for years. Three that actually changed our roadmap.Mon, 06 Jan 2025 00:00:00 GMTSetting up k3s on a mini PC for staging and why every startup needs a junk drawer environmenthttps://anshulbisen.com/blog/k3s-mini-pc-staging-junk-drawer-environment/https://anshulbisen.com/blog/k3s-mini-pc-staging-junk-drawer-environment/A $300 mini PC running k3s gave our team a staging environment that mirrors production topology without the cloud bill. The real value was deployment confidence.Mon, 23 Dec 2024 00:00:00 GMTThe meeting where product, sales, and engineering all had different definitions of "real-time"https://anshulbisen.com/blog/three-definitions-of-real-time/https://anshulbisen.com/blog/three-definitions-of-real-time/Product wanted sub-second dashboard updates. Sales had promised "real-time" reconciliation. Engineering was thinking about eventual consistency with 30-second polling. One word nearly derailed a quarter of work.Mon, 16 Dec 2024 00:00:00 GMTReact 19 Server Components in production: the migration nobody warns you abouthttps://anshulbisen.com/blog/react-19-server-components-migration-nobody-warns-you/https://anshulbisen.com/blog/react-19-server-components-migration-nobody-warns-you/React 19 shipped with Server Components stable and the React Compiler, but migrating a real fintech dashboard was nothing like the blog posts suggested.Mon, 09 Dec 2024 00:00:00 GMTWhy our compliance team rewrites my API specs and I have learned to be gratefulhttps://anshulbisen.com/blog/compliance-rewrites-api-specs-grateful/https://anshulbisen.com/blog/compliance-rewrites-api-specs-grateful/In fintech, your API surface is a regulatory document. Our compliance officer started redlining my OpenAPI specs and improved our API design more than any tech review.Mon, 25 Nov 2024 00:00:00 GMTHiring engineer number three when you can barely keep engineer number one from burning outhttps://anshulbisen.com/blog/hiring-engineer-three-while-one-burns-out/https://anshulbisen.com/blog/hiring-engineer-three-while-one-burns-out/I posted a job listing for our third engineer while privately wondering if our first hire was about to quit. What I got wrong about workload distribution.Mon, 18 Nov 2024 00:00:00 GMTWhat Payload CMS 3.0 taught me about choosing frameworks that grow with youhttps://anshulbisen.com/blog/payload-cms-3-choosing-frameworks-that-grow/https://anshulbisen.com/blog/payload-cms-3-choosing-frameworks-that-grow/Payload CMS 3.0 shipped with native Next.js App Router integration, validating a framework evaluation approach that prioritizes embeddability over feature count.Mon, 11 Nov 2024 00:00:00 GMTThe day our monolith's database hit 80% CPU and nobody noticed until sales calledhttps://anshulbisen.com/blog/database-80-percent-cpu-sales-called/https://anshulbisen.com/blog/database-80-percent-cpu-sales-called/A slow query compounded by a missing index took our PostgreSQL instance to the brink. Sales noticed before engineering did because client reports were timing out.Mon, 04 Nov 2024 00:00:00 GMTClaude 3.5 Sonnet v2 and the week I mass-refactored our codebase with an AI pair programmerhttps://anshulbisen.com/blog/claude-35-sonnet-v2-ai-pair-programmer-refactor/https://anshulbisen.com/blog/claude-35-sonnet-v2-ai-pair-programmer-refactor/I used Claude 3.5 Sonnet v2 to refactor our error handling layer, migrate 80 test files, and generate TypeScript types from our OpenAPI spec. This is a workflow journal.Wed, 23 Oct 2024 00:00:00 GMTNext.js 15, Turbopack stable, and the mass codebase migration nobody is talking abouthttps://anshulbisen.com/blog/nextjs-15-turbopack-stable-mass-migration/https://anshulbisen.com/blog/nextjs-15-turbopack-stable-mass-migration/Next.js 15 shipped with Turbopack stable and async request APIs that break every existing middleware and dynamic page in your application.Wed, 09 Oct 2024 00:00:00 GMTThe night our database ran out of connections and what I learned about poolinghttps://anshulbisen.com/blog/database-connection-pool-exhaustion-lessons/https://anshulbisen.com/blog/database-connection-pool-exhaustion-lessons/At 2am our payment processing froze. Every database connection was consumed by long-running report queries sharing a pool with transactions.Wed, 25 Sep 2024 00:00:00 GMTMaking technology bets: how I evaluate frameworks when the wrong choice costs a yearhttps://anshulbisen.com/blog/making-technology-bets-framework-evaluation/https://anshulbisen.com/blog/making-technology-bets-framework-evaluation/At a startup, picking the wrong framework is a survival threat. Here is the five-criteria scoring model I use for every significant technology decision.Wed, 18 Sep 2024 00:00:00 GMTPostgreSQL 17 just dropped and COPY performance alone makes the upgrade worth ithttps://anshulbisen.com/blog/postgres-17-copy-performance-upgrade-worth-it/https://anshulbisen.com/blog/postgres-17-copy-performance-upgrade-worth-it/PostgreSQL 17 shipped with 2x COPY performance, JSON_TABLE, and MERGE with RETURNING. The COPY improvement cut our nightly import from 12 minutes to under 6.Wed, 11 Sep 2024 00:00:00 GMTObservability on a shoestring: Grafana, Loki, and Tempo for freehttps://anshulbisen.com/blog/observability-grafana-loki-tempo-free/https://anshulbisen.com/blog/observability-grafana-loki-tempo-free/We could not afford Datadog. I self-hosted the Grafana stack on our k3s homelab cluster and pointed production at it.Wed, 04 Sep 2024 00:00:00 GMTWhy every API endpoint at FinanceOps returns the same error shapehttps://anshulbisen.com/blog/consistent-api-error-shape-everywhere/https://anshulbisen.com/blog/consistent-api-error-shape-everywhere/Our frontend had seven different error format handlers. I standardized every endpoint to return the same discriminated union error shape.Wed, 28 Aug 2024 00:00:00 GMTFull-stack chaos: when the founder, PM, and head of engineering are all youhttps://anshulbisen.com/blog/full-stack-chaos-founder-pm-engineer-all-you/https://anshulbisen.com/blog/full-stack-chaos-founder-pm-engineer-all-you/In a single Tuesday I triaged a database lock, wrote a product spec, pitched an investor, and reviewed a PR. Wearing every hat is a failure mode.Wed, 21 Aug 2024 00:00:00 GMTThe PostgreSQL query that took 47 seconds and how I got it to 3 millisecondshttps://anshulbisen.com/blog/postgres-query-47-seconds-to-3ms/https://anshulbisen.com/blog/postgres-query-47-seconds-to-3ms/A financial report query joined five tables across 2 million rows and took 47 seconds. The fix was not adding an index.Wed, 14 Aug 2024 00:00:00 GMTArgoCD on a single-node k3s cluster: overkill or exactly righthttps://anshulbisen.com/blog/argocd-single-node-k3s-overkill-or-right/https://anshulbisen.com/blog/argocd-single-node-k3s-overkill-or-right/Everyone told me ArgoCD on a single-node homelab was absurd. GitOps on a single node means I can rebuild from a Git repo in under 10 minutes.Wed, 07 Aug 2024 00:00:00 GMTDocker multi-stage builds that actually make your images smallhttps://anshulbisen.com/blog/docker-multi-stage-builds-small-images/https://anshulbisen.com/blog/docker-multi-stage-builds-small-images/Our production Docker image was 1.2 GB. After an afternoon of optimization it was 89 MB. Here is the exact Dockerfile evolution.Wed, 31 Jul 2024 00:00:00 GMTHiring our first engineer: the mass-interview process I built as a non-recruiterhttps://anshulbisen.com/blog/hiring-first-engineer-non-recruiter/https://anshulbisen.com/blog/hiring-first-engineer-non-recruiter/No ATS, no recruiter, no playbook. I built the entire hiring pipeline from scratch and we interviewed 30 candidates to make one perfect hire.Wed, 24 Jul 2024 00:00:00 GMTWhy we picked React Server Components over a separate API layerhttps://anshulbisen.com/blog/react-server-components-over-separate-api/https://anshulbisen.com/blog/react-server-components-over-separate-api/I tried React Server Components for our internal dashboard and realized I could eliminate the entire API serialization layer for read-heavy pages.Wed, 17 Jul 2024 00:00:00 GMTBuilding a payment reconciliation engine that catches every pennyhttps://anshulbisen.com/blog/payment-reconciliation-engine-every-penny/https://anshulbisen.com/blog/payment-reconciliation-engine-every-penny/When your product handles financial transactions, close enough is not a rounding strategy. Here is the three-way reconciliation engine I built.Wed, 10 Jul 2024 00:00:00 GMTSetting up Cloudflare Tunnels so I never open a port on my homelab againhttps://anshulbisen.com/blog/cloudflare-tunnels-homelab-zero-ports/https://anshulbisen.com/blog/cloudflare-tunnels-homelab-zero-ports/I replaced every port forward with a zero-trust Cloudflare Tunnel in a single evening. Here is the exact setup.Wed, 03 Jul 2024 00:00:00 GMTTypeScript 5.5 inferred type predicates changed how I write validation codehttps://anshulbisen.com/blog/typescript-55-inferred-type-predicates/https://anshulbisen.com/blog/typescript-55-inferred-type-predicates/TypeScript 5.5 shipped inferred type predicates and it quietly eliminated an entire category of boilerplate in our codebase.Wed, 26 Jun 2024 00:00:00 GMTThe AWS bill that made me rethink everything about infrastructurehttps://anshulbisen.com/blog/aws-bill-rethink-infrastructure/https://anshulbisen.com/blog/aws-bill-rethink-infrastructure/Our third month AWS bill was 4x what I projected. The culprit was not compute. It was data transfer, NAT gateway charges, and CloudWatch log ingestion.Wed, 19 Jun 2024 00:00:00 GMTHow I use PostgreSQL as a job queue and why you probably should toohttps://anshulbisen.com/blog/postgres-as-job-queue/https://anshulbisen.com/blog/postgres-as-job-queue/Every guide says use Redis or BullMQ for background jobs. I used PostgreSQL SKIP LOCKED and it handled thousands of jobs per day with zero additional infrastructure.Wed, 12 Jun 2024 00:00:00 GMTStartup engineering culture when you are the only engineerhttps://anshulbisen.com/blog/startup-engineering-culture-only-engineer/https://anshulbisen.com/blog/startup-engineering-culture-only-engineer/For the first four months I was the entire engineering department. No code reviews, no architecture discussions. Here are the practices I invented to stay honest.Wed, 05 Jun 2024 00:00:00 GMTBuilding a real-time notification system with zero external dependencieshttps://anshulbisen.com/blog/real-time-notifications-zero-dependencies/https://anshulbisen.com/blog/real-time-notifications-zero-dependencies/We needed real-time payment notifications but could not justify Redis or a managed WebSocket service. SSE and PostgreSQL LISTEN/NOTIFY did the job.Wed, 29 May 2024 00:00:00 GMTNode.js 22 dropped and here is what actually matters for production backendshttps://anshulbisen.com/blog/node-22-what-matters-production-backends/https://anshulbisen.com/blog/node-22-what-matters-production-backends/Node.js 22 shipped with require(esm) and a built-in WebSocket client. Here is what I benchmarked and what I adopted immediately.Wed, 22 May 2024 00:00:00 GMTMy first homelab rack: a mini PC, k3s, and the itch to self-host everythinghttps://anshulbisen.com/blog/first-homelab-rack-mini-pc-k3s/https://anshulbisen.com/blog/first-homelab-rack-mini-pc-k3s/I bought a used mini PC for $180, installed k3s, and spent a weekend migrating my side projects off Vercel free tier.Wed, 15 May 2024 00:00:00 GMTDesigning a multi-tenant PostgreSQL schema that does not make you cry at 3amhttps://anshulbisen.com/blog/multi-tenant-postgres-schema-design/https://anshulbisen.com/blog/multi-tenant-postgres-schema-design/Shared database, shared schema, row-level security. That was the bet. Here is how it played out.Wed, 08 May 2024 00:00:00 GMTWhat nobody tells you about building fintech: compliance is a product featurehttps://anshulbisen.com/blog/fintech-compliance-is-product-feature/https://anshulbisen.com/blog/fintech-compliance-is-product-feature/I walked into FinanceOps thinking I was building software. Six months later I realized I was building a compliance platform that happens to have software around it.Wed, 01 May 2024 00:00:00 GMTThe mass migration: moving 200 API endpoints to TypeScript strict mode in one sprinthttps://anshulbisen.com/blog/mass-migration-200-endpoints-typescript-strict/https://anshulbisen.com/blog/mass-migration-200-endpoints-typescript-strict/A production bug from an unchecked null cost us a weekend. I spent the next sprint converting 200 API endpoints to strict mode.Wed, 24 Apr 2024 00:00:00 GMTStanding up CI/CD from scratch with GitHub Actions and zero budgethttps://anshulbisen.com/blog/ci-cd-from-scratch-github-actions-zero-budget/https://anshulbisen.com/blog/ci-cd-from-scratch-github-actions-zero-budget/No DevOps person. No budget. I built our entire CI/CD pipeline in a single weekend using GitHub Actions free tier.Wed, 17 Apr 2024 00:00:00 GMTBootstrapping a Next.js monolith when everyone says microserviceshttps://anshulbisen.com/blog/nextjs-monolith-over-microservices/https://anshulbisen.com/blog/nextjs-monolith-over-microservices/I shipped our entire fintech platform as a single Next.js application. Here is why a monolith was the right call for a team of three.Wed, 10 Apr 2024 00:00:00 GMTWhy I chose PostgreSQL over MongoDB and how it shaped our entire fintech stackhttps://anshulbisen.com/blog/why-postgres-over-mongo-fintech-stack/https://anshulbisen.com/blog/why-postgres-over-mongo-fintech-stack/Every fintech startup I talked to was defaulting to MongoDB. I went the other way and bet on PostgreSQL with strict schemas from day one.Wed, 03 Apr 2024 00:00:00 GMT