# Lean Canvas — Brainshelf Resurface

Created: 2026-04-15
Purpose: New feature thesis, pre-scope sanity check and board-update anchor
Overall confidence: Low to Medium
1Problem
M

- Saves never revisited: roughly 1:0.3 save-to-read ratio [fictional]; most saved content is functionally lost
- Forgotten saves erode perceived value, driving disengagement and churn
- Competitors (Readwise, Raindrop) have resurfacing features; the gap is visible to cross-shopping users

Existing alternatives

- Readwise Reader daily review emails (most direct competitor)
- Raindrop.io read-later section (passive, no reminders)
- Email-to-self with manual inbox review
- Non-consumption: accepting forgotten saves as a cost of doing business

4Solution
L

- Daily AM email digest with 3 curated items selected for contextual relevance
- One-click revisit or archive from the email, with streak tracking
- Relevance scoring that differentiates from Readwise's chronological rotation

3Unique Value Proposition
L
The article you saved last week, delivered Monday morning before your first meeting.
High-level concept
Day-one reminder for your second brain.
9Unfair Advantage
L
Open question. Candidate: our existing save-behavior data (what users save, read, and abandon) could power better contextual relevance scoring than new entrants. But only if we ship the scoring model. If we ship naive chronological first, we forfeit the advantage and compete on email frequency, which is not defensible.
2Customer Segments
M
Active Brainshelf users (3+ saves per week) across consumer PKM use cases.
Early adopters
Knowledge-worker users with 50+ saved items AND desktop notifications enabled. Approximately 12% of active base (~2,300 users) [fictional]; have signaled openness to proactive nudges.
8Key Metrics
L

- Day-1 and day-7 retention of Resurface users (target 40% / 20%) [fictional]
- Save-to-revisit ratio lift: 1:0.3 to 1:0.6 within 6 months [fictional]
- Email open 35%, click-through 12%
- Curator free-to-paid conversion: 4% month 1, 8% month 12
- Referral rate: from 2.1 to 3.2 invites per active user per quarter [fictional]

5Channels
L
Compounding (free, long-horizon)

- Product-led growth: users share digests with teammates, CTA embedded
- Content on "the tool you save to vs come back to" (Twitter, LinkedIn)
- Integration with Notion, Obsidian as import-export bridges

Traction-demonstrating (paid, near-term)

- Referral program: 3 invites = 30 days Curator free for both sides
- App Store and Play Store feature partnerships timed with v1 launch

7Cost Structure
M

- CAC ~$4 blended (heavy reliance on organic + referral) [fictional]
- Fixed: ~$450k annual burn (small team) [fictional]; Resurface adds minimal headcount pressure
- Variable: SES email ($0.0001/send), relevance-scoring inference ($0.002/digest)
- Cost driver: relevance-scoring inference. Larger model triples per-user COGS; lean scoring is a design constraint

6Revenue Streams
L

- Model: freemium with "Curator" paid tier unlocking unlimited saves and advanced relevance
- Price: $5/mo or $50/yr; Curator tier adds priority sync
- Volume (Y1): 8% free-to-paid x active base = ~1,600 paid users [fictional]
- LTV: ~$70 per user (14-month avg lifetime)
- Math: 1,600 x $60 avg annual = ~$96k Y1 ARR; real bet is compounding engagement lift