A worked example of [[Shared Second Brain|building a shared second brain]] at organisational scale, traced through pain → cluster → quality bar → method → tool. Both questions matter: the pain-to-method line resolves to a cross-project decision log; the people-to-ownership line resolves to a standing review group. ## In one line Teams repeating each other's mistakes across projects → cross-project decision rationale cluster, non-negotiables *discoverability* + *connectivity across projects* → [[Architecture Decision Record|shared technical decision log]] with a standing review group → [[Notion]]. ^one-line ## The acts in one line each Different teams kept making the same technical mistakes; per-project [[Architecture Decision Record|ADRs]] existed but were invisible across project boundaries. ^trail-line Cross-project decision rationale - rare, high-consequence, stable, highly connected, consumed by future tech leads and by [[AI agent|agents]]. Non-negotiables: *discoverability across projects* and *connectivity across projects*. ^profile-line Process-embedded capture as a shared [[Decision log|technical decision log]] common to the whole organisation, with a small standing review group as steward. ^method-line ## Full walkthrough ### Knowledge trail mapping Different teams in the same organisation kept making the same technical mistakes. A new project would evaluate, say, an event bus pattern and reject it - then six months later, a different team would evaluate the same pattern from scratch, reject it for the same reasons, and never know the first team had been there. [[Architecture Decision Record|ADRs]] existed inside each project's own repo - invisible to anyone outside it. The trail went cold at the project boundary. The people side: each project's tech lead held the rationale informally. Cross-project conversations happened in scattered Slack threads with no shared record. The informal brokers were a handful of senior engineers who happened to span multiple projects. ### Knowledge domain profiling The cluster: decision rationale, cross-project, technical. Created by tech leads and senior engineers, infrequently. Consumed by future tech leads on different projects, by new engineers onboarding, and by [[AI agent|agents]] doing code review or architectural assistance. Volatility low - architectural decisions are stable. Connectivity high - each decision relates to others. Cost of being missing: high - repeated effort, repeated mistakes, contradictory patterns across the organisation. Artifacts produced today: per-project ADRs (good). Cross-project index, shared search, shared linking: none (bad). The quality bar: - Discoverability - a tech lead on a new project must find a relevant prior decision in under five minutes, without knowing which project to look in - Connectivity - decisions across projects must link to each other - Maintainability - writing a new ADR must not slow the actual decision - Survivability - must outlast any one project's lifetime - Agent-readiness - structured and plain enough that an agent can pull context from it Non-negotiables: *discoverability across projects* and *connectivity across projects*. Without those, the per-project ADRs already in place are not the failure; the failure is the lack of an organisational layer above them. Steward candidates surfaced from the previous act: the senior engineers spanning multiple projects. ### Knowledge methodology matching Process-embedded capture, specifically a shared [[Decision log|technical decision log]] common to the whole organisation. The discipline: every cross-project-relevant decision goes in the shared log, tagged with its project of origin, the alternatives considered, and the constraints that ruled. A small standing review group (drawn from the spanning senior engineers) confirms each entry so it counts as an organisational decision, not just a project one. ### Tool (illustrative, after the workshop) Notion - linked databases for cross-project tagging and querying, comfortable for non-engineers to read, in the same workspace where the organisation's process documentation already lived. The tool followed the method (shared, queryable, cross-linkable), not the other way around.