CLN Wiki · Organizational Knowledge
Knowledge Rot
When your best engineer quits, what leaves with them?
01
/
Definition
Analysis
=
Knowledge Rot — institutional knowledge decays when carriers leave
Fortune 500 companies lose billions annually to knowledge loss from turnover. When a senior engineer leaves, they take the context: why the system was built that way, which approaches were tried and failed, where the hidden risks are. That context lives in their head and Slack. Both disappear.
02
/
What's Lost
Three Orders
Explicit
How the system works
Partially captured in docs — often outdated
Tacit
WHY the system works this way
Almost never captured — lives in memory and Slack
Negative
What was tried and FAILED
Never captured — new team repeats old mistakes
03
/
Why Prose Fails
Problem
-
prose explains WHAT, not WHY
-
decision rationale buried in paragraphs
-
failed approaches never documented
04
/
The CLN Preservation Pattern
Solution
.
DECISION RECORDS in CLN capture:
=
the decision and its context
+
why this option was chosen (with data)
-
why alternatives were rejected (negative knowledge!)
!
known risks accepted at the time
?
unknowns that were deferred
+
a new engineer reads this in 2 minutes
+
they don't repeat approaches marked with
-
Example — Decision Record in CLN
=
Decision: use PostgreSQL for session storage
+
chosen: transactional guarantees needed for billing
-
tried Redis; failed under concurrent writes >5K/sec
!
risk accepted: read latency ~12ms vs 1ms with Redis
?
deferred: evaluate Redis Cluster if writes exceed 50K/sec
@
owner: A. Petrov · 2025-11-14
05
/
The Negative Knowledge Gap
Key Insight
*
the most valuable knowledge is negative knowledge — what doesn't work and why
*
a single
- line saves the next team weeks
*
10 seconds to write, decades of value
The cost of lost knowledge is invisible until someone rediscovers a problem you already solved.