psf-memo/specs/feature-backlog.md

psf-memo — Prioritized Feature Backlog

Status: DRAFT — saved for future development cycles. Owner: specifier Last updated: 2026-08-26

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Goal

Make psf-memo feature-equivalent to memo.cash, a Bitcoin Cash (BCH) social network built on OP_RETURN transactions. Every social action is a BCH transaction carrying a Memo protocol payload (0x6d + action byte) that is broadcast from the client to the chain and later indexed by psf-memo-indexer into psf-memo-db.

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Architecture constraints

• Identity/auth: the auto-generated HD wallet (12-word mnemonic) persisted in browser Local Storage by the existing React app is the Memo identity.
• Write path: broadcasting is done via minimal-slp-wallet.sendOpReturn().
  • Correct public API: await wallet.sendOpReturn(message, prefix).
  • prefix = '6d02' posts a memo; other action bytes replace 02.
  • Binary payloads (txid, address hash) must be encoded correctly.
• Read path: psf-memo-db REST API (/posts/*, /profile/*, /level/*). API changes are in scope for specs.
• Indexer path: psf-memo-indexer scans blocks and mempool for Memo OP_RETURN outputs and writes structured records to psf-memo-db.
• The write path (broadcast), indexer path, and read path (DB) are asynchronous: a broadcasted action becomes visible only after confirmation + indexing.

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Memo protocol action codes

Reference: https://memo.sv/protocol

Action byte	Meaning
0x6d01	Set name
0x6d02	Post memo
0x6d03	Reply to memo
0x6d04	Like / tip memo
0x6d05	Set profile text
0x6d06	Follow user
0x6d07	Unfollow user
0x6d0a	Set profile picture
0x6d0b	Repost memo (planned)
0x6d0c	Post topic message
0x6d0d	Topic follow
0x6d0e	Topic unfollow
0x6d10	Create poll
0x6d13	Add poll option
0x6d14	Poll vote
0x6d16	Mute user
0x6d17	Unmute user
0x6d24	Send money
0x6d30–0x6d35	MIP-0009 token sell / buy / attach signature / pin

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Component legend

Code	Component	Typical changes
C	psf-memo-client	React components, services, pages, unit/acceptance tests
I	psf-memo-indexer	Memo action handler, parser support, filter logic
D	psf-memo-db	LevelDB store, REST route, query adapter, tests

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Tier P1 — Core social verbs (write + read)

These are the foundational posting and identity actions. Each is a broadcast action plus its read/display surface and indexer support.

#	Feature	Memo action	Components	Write	Read surface	Status
1	Post a Memo	0x6d02	C	Compose + sendOpReturn	Appears in recent feed & own profile after indexing	✅ DONE
2	Set display name	0x6d01	C	Broadcast name	Name shown on posts, profiles, feed	✅ DONE
3	Reply to a Memo	0x6d03	C	Broadcast reply to parent txid	Nested thread view	✅ DONE
4	Like / tip a Memo	0x6d04	C, I, D	Broadcast like for a post txid; optional BCH tip	Like count + liked state on post	TODO
5	Set profile text (bio)	0x6d05	C, I, D	Broadcast bio	Shown on profile page	TODO
6	Set profile picture	0x6d0a	C, I, D	Broadcast avatar URL	Avatar on profile + posts	TODO
7	Follow a user	0x6d06	C, I, D	Broadcast follow of address	Follow button state; following list	TODO
8	Unfollow a user	0x6d07	C, I, D	Broadcast unfollow	Follow button state; following list	TODO

Priority order within P1

1. Post a Memo — the primary verb; unblocks all others. ✅ DONE
2. Set display name — makes the feed readable. ✅ DONE
3. Reply to a Memo — core conversation. ✅ DONE
   • Decisions (2026-08-26, from memo.cash UI review): reply max = 184 bytes (UTF-8 byte count); reply form inside the thread modal; keep existing comment-icon behavior; live [remaining] byte counter (red when over); update thread optimistically after broadcast; reply to a reply (nested).
4. Like / tip a Memo — social signal; needs like-count API + indexer handler.
5. Set profile text — bio for the profile page.
6. Set profile picture — avatar for posts/profiles.
7. Follow a user.
8. Unfollow a user.

Like / tip details

The like action (0x6d04) carries the liked post txid (32 bytes). A pure like has no BCH output to the author; a tip adds a P2PKH output paying the author. The indexer must:

• Store the like event in likes keyed by like txid.
• Update per-post like counts (likely a derived query or likes scan).
• Optionally store tip amount when the like tx pays the author.

The client must:

• Show a heart icon on each post.
• Open a like/tip modal with optional tip amount.
• Validate tip amount (dust limit, spendable balance).
• Broadcast OP_RETURN 6d04 <postTxid> plus any tip output.

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P2 — Topics

#	Feature	Memo action	Components
9	Post a topic message	0x6d0c	C, I, D
10	Follow a topic	0x6d0d	C, I, D
11	Unfollow a topic	0x6d0e	C, I, D
12	Topic feed page	read	C, D

Needs: topics index in psf-memo-db, topic feed endpoint, topic follow state.

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P3 — Polls (later)

#	Feature	Memo action	Components
13	Create a poll	0x6d10	C, I, D
14	Add a poll option	0x6d13	C, I, D
15	Vote in a poll	0x6d14	C, I, D

Needs: poll data model + rendering + vote aggregation in psf-memo-db.

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P4 — Moderation (later)

#	Feature	Memo action	Components
16	Mute a user	0x6d16	C, D
17	Unmute a user	0x6d17	C, D

Needs: per-wallet mute list applied to feed filtering.

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P5 — Money & tokens (later)

#	Feature	Memo action	Components
18	Send money	0x6d24	C
19	Token sell / buy / pin	0x6d30–0x6d35 (MIP-0009)	C, I, D

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P6 — Discovery & UX (later)

#	Feature	Components	Notes
20	Search	C, D	posts / profiles / topics / tags
21	Tags / hashtags	C, D	link + filter by tag
22	Notifications	C, D	replies / likes / follows to my posts
23	Ranked feed	C, D	memo.cash "ranked" post ordering
24	Repost	C, I, D	0x6d0b (planned in protocol)

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Read-only vs write capability by cycle

• Cycle 0 (current): read-only display of recent posts, profiles, post threads.
• Cycle 1 (P1): add write code paths (broadcast via sendOpReturn). UI is read-only until a broadcasted action is confirmed + indexed; then the feed/profile refresh.
• Later cycles: topics, polls, moderation, money/tokens, discovery.

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Notes for future cycles

• Broadcast result (txid) is returned immediately; the action appears in the feed only after block confirmation + indexing. Specs must reflect this async visibility.
• Mutations/specs are Gherkin feature files under per-component specs/ in the format defined by github.com/unclebob/Acceptance-Pipeline-Specification.
• Root specs/ contains this backlog and cross-component architecture notes.