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Architecture/system_prompt

Architecture — system_prompt

Behavior rules for this folder, layered on top of README.md's global rules per its "System Prompts Per Project/Feature" table. Read this immediately after the README whenever working inside Architecture/.

Purpose

A knowledge base for professional Solutions/Software Architect understanding — not a certification tracker, not a news digest. Goal is retained, applicable architecture judgment, targeted broadly at Principal Engineer growth (system design maturity, tradeoff articulation, architecture-review communication), not locked to any one domain. Mihir is not domain-locked to Network (his current job) — he thinks contractor-style, targeting Fintech, Capital Markets, and BigTech broadly. See [[user-professional-profile]] memory for the full framing.

CertPath/ was deliberately dropped from this folder's scope — a cert ladder is a study checklist, not knowledge growth.

Pillar taxonomy

Not a certification checklist — an organizing scheme. AWS's SAA-C03 (Associate) and SAP-C02 (Professional) exam domains are vendor packaging of universal architecture concerns, and they map almost 1:1 onto the AWS Well-Architected Framework's pillars. Deduping the Associate's 4 domains and the Professional's 5 domains (both include Cost, for instance) gives six pillars used across this whole folder:

Pillar tag Covers
pillar-security Least privilege, defense in depth, threat modeling
pillar-resilience Failover, multi-AZ/region, disaster recovery, blast-radius containment
pillar-performance Caching, latency budgets, scaling patterns
pillar-cost Tradeoffs between the above pillars and spend
pillar-operational-excellence Observability, automation, incident response
pillar-org-complexity Multi-account/multi-team design, legacy migration & modernization (Professional-level territory, genuinely relevant at Principal scope)

Fundamentals/ notes are bucketed by pillar in _index.md — each note's primary pillar tag decides which bucket it lists under (a note can carry more than one pillar tag if it genuinely spans two, but should list under its primary one to avoid duplication).

CaseStudies/ and Challenges/ notes stay flavor-first (not reorganized into pillar buckets), but every note gets at least one pillar-* tag in frontmatter so cross-cutting patterns become visible over time — e.g. a payments idempotency case study is tagged pillar-resilience, not filed under a "Resilience" folder.

The three flavors

Flavor What it is Who writes it
Fundamentals/ Timeless concept notes (VPC design, caching layers, storage tradeoffs, etc.) Hand-curated by Mihir + Claude interactively, or the daily routine once scheduled
CaseStudies/ Real-world architecture breakdowns, ByteByteGo-style (how company X solved scaling/reliability problem Y) Sourced from writelist.md; best fit for autonomous daily discovery since new write-ups appear regularly
Challenges/ Design-scenario practice — a prompt, Mihir's own attempt, then a model solution Scenario + model solution can be routine-generated, but Mihir's attempt is written by him, not the routine

Filenames: kebab-case, no spaces

Every note file in Fundamentals/, CaseStudies/, and Challenges/ uses a kebab-case filename (lowercase, hyphen-separated — e.g. circuit-breaker-pattern.md), matching AIDigest/'s own slug convention. The human-readable title still lives in frontmatter (title: "Circuit Breaker Pattern") and the # H1 — only the filename itself is kebab-case.

Why: the first batch of notes used spaced Title-Case filenames (Circuit Breaker Pattern.md), which triggered a real bug in the hosted viewer — Next.js's catch-all route wasn't decoding %20 in URL segments, so clicking through the sidebar 404'd on every spaced filename (fixed in viewer/app/(app)/[[...slug]]/page.tsx by explicitly decodeURIComponent-ing each segment). That underlying bug is fixed and spaced filenames would work now too, but kebab-case stays the convention here as defense-in-depth and for consistency with AIDigest.

Wikilinks to these notes should use the piped form to keep a readable display name: [[circuit-breaker-pattern\|Circuit Breaker Pattern]], not a bare [[Circuit Breaker Pattern]] (which would try to resolve a note literally named that).

Note template (every note, all three flavors)

Frontmatter is mandatory per README rules (title, tags, source, created). Body structure differs slightly per flavor:

Fundamentals:

  1. Concept
  2. Tradeoffs
  3. When to use / when not to
  4. Common pitfall
  5. ## Principal Engineer Lens (see below)
  6. ## Reel Script (optional — only if there's 5-10 min of real teaching material; no padding)
  7. ## Related

CaseStudies:

  1. Problem + constraints
  2. Solution
  3. What to steal (patterns worth reusing elsewhere)
  4. ## Principal Engineer Lens
  5. ## Reel Script (compulsory — case studies always have something concrete to teach)
  6. ## Related

Challenges:

  1. Scenario prompt
  2. Mihir's attempt (left as a > [!todo] placeholder if not yet written — never fabricated by the routine)
  3. Model solution
  4. Gaps to revisit
  5. ## Principal Engineer Lens
  6. ## Reel Script (compulsory)
  7. ## Related

## Principal Engineer Lens section

Replaces a domain-locked "so what" callout. Default framing is broad: how this pattern sharpens system-design judgment, tradeoff reasoning, or how you'd defend/communicate this decision in an architecture review — the kind of thing that reads as Principal-level thinking regardless of employer. Only tie back to Mihir's current Network tooling (NetBox, Aegis, PIV, Cisco APIC, etc.) when the mapping is genuine and specific — never forced, never as a rote closing line. When a case study naturally leans toward Fintech/Capital Markets/BigTech-style problems (payments, trading systems, large-scale consumer platforms), bias the framing that direction over Network, since that's where Mihir is actually aiming his career.

## Reel Script section — "Learn and Educate"

Distinct from AIDigest's reel section (2-5 min, hook-driven, "cut through AI marketing fluff" angle for social content). This one exists purely as a learning-by-teaching mechanism — Mihir records himself explaining the note out loud, 5-10 minutes, as a second retention pass after reading. Longer and deeper than AIDigest's reel, no hook-bait framing needed.

Beats:

  1. Setup — state the problem/scenario plainly, no hook-bait
  2. Concept walkthrough — explain the mechanism as if teaching a peer
  3. Real example / case study tie-in — walk the concrete case or challenge step by step
  4. Tradeoffs & alternatives — what else could've been used, why this won, when you'd choose differently
  5. Principal Engineer takeaway — same broad framing as the Lens section above, not a repeat of it verbatim

Compulsory on CaseStudies and Challenges. Optional on Fundamentals — only include when the concept has enough real depth for 5-10 min; thin concepts stay short rather than padded, same philosophy as AIDigest's eligibility gate.

Flavor rotation (live daily routine)

Scheduled 2026-07-19 as Architecture Scheduler (trig_01CDFuy8NfboDcW1JpsCW87X, cron 0 17 2-31 * * UTC = 12pm EST, skips the 1st of the month) — see architecture-scheduler for full configuration and why this slot. It round-robins through Fundamentals → CaseStudies → Challenges → repeat, tracked via a current_flavor: pointer in writelist.md. No hard cap on notes per run — same "quality over fixed quota" philosophy as AIDigest, writes as many as there's genuine material for, not exactly one.

Cadence history: started daily — deliberately aggressive at first since the folder had zero content and needed a "crash course" pace, proven out first with 3 hand-written test notes (one per flavor) before scheduling. The Weekend Tech Vocab Scraper was disabled the same day to make room in the daily Claude-usage budget. Revisit checkpoint: ~2026-10-19 (3 months out) — drop to weekly once Fundamentals/Challenges notes start feeling repetitive. CaseStudies alone can likely sustain daily longer since real-world write-ups keep appearing.

Weekly rollup note

Separate from the per-flavor notes: once a week, a rollup note (location/format TBD — likely Architecture/Rollups/YYYY-MM-DD.md) summarizes that week's new notes across all three flavors into one skimmable page, so learning gets a spaced-repetition-style second touch without extra research cost — it's just synthesizing what's already written that week.

Dedup

Same pattern as AIDigest: a _sources.md log (create when the scheduler goes live) tracks every source URL already covered, checked before spending research effort on a candidate.

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