cloud-sync-module

A TypeScript module that keeps one kind of user data consistent between the app and its encrypted cloud copy.

In plain words
What is it for?
Use it when creating, reviewing, or debugging a cloud data manager, its aggregation setup, or its required contract tests.
Why use it?
It provides rules for comparing, merging, and applying data updates without accidentally losing changes.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/ledgerhq/ledger-live/cloud-sync-module
Any agent
npx skills add LedgerHQ/ledger-live --skill cloud-sync-module
Clone the repo
git clone --depth 1 https://github.com/LedgerHQ/ledger-live

Made for: Claude Code, Codex.

Per session 88 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,332 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00088 $0.02332
Opus 5 $0.00044 $0.01166
Sonnet 5 $0.00018 $0.00466
Haiku 4.5 $0.00009 $0.00233

Measured 3d ago against content hash 06e836d66de2, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

cloud-sync-module scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.agents/skills/cloud-sync-module/SKILL.md · 141 lines

How it starts

The opening of the file, as written. The whole thing — 141 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Authoring a cloudSyncModule.ts

A module reconciles LocalState (what the app holds, from Redux) with DistantState (what is stored encrypted in Cloud Sync). createAggregator composes every module into one blob shared by all of the user's instances (LWD, LWM, web-tools).

Concepts: 05-wallet-sync-data-manager, then 06-watch-loop for when each hook fires. Steps and a video: cookbook. Testing layers: test-strategy. Contract: @shared/cloud-sync-module. Copy account-name (simplest); accounts for async + injected ctx; recent-addresses for the tolerant-list schema only — its .transform() use is a known bug (see below).

The three hooks

Hook Sync? Runs Must return
diffLocalToDistant(local, latest) sync every loop tick (~10s) before push { hasChanges, nextState } — what to push
resolveIncrementalUpdate(local, latest, incoming) async on pull and every tick with incoming === latest { hasChanges: false } or { hasChanges: true, update }
applyUpdate(local, update) sync only when the above reported changes the new LocalState (pure, no mutation)

Live under domain/entity/<name>/src/cloudSyncModule.ts beside schema.ts + slice.ts (see domain/entity/README.md). Type it CloudSyncDataManager<LocalState, Update, typeof schema>, with hasChanges: false as const so the union narrows. A 4th generic DistantState defaults to z.infer<Schema> — pass the raw wire type explicitly if your schema transforms, since that is what the hooks actually receive.

Read the full file on GitHub · 141 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 3d ago First seen · 141 lines · 88 tokens per session scan A 06e836d66de2

Subscribe to this mod's changes

cloud-sync-module is a skill published in the GitHub repository LedgerHQ/ledger-live (614 stars, last pushed 3d ago), licensed MIT. It adds 88 tokens to every session and 2,332 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Related

Other skills, from other repositories

client-setup

Create a vanilla tRPC client with createTRPCClient (), configure link chain with httpBatchLink/httpLink, dynamic headers for auth, transformer on links (not client constructor). Infer types with inferRouterInputs and inferRouterOutputs. AbortController signal support. TRPCClientError typing.

trpc/trpc · 63 tokens

custom-features

Author a TanStack Table v9 feature plugin across every FeatureMap and API installation surface: state, options, column definitions, table, column, row, cell, header, row-model functions/caches, defaults, prototypes, and table/row/column instance data lifecycles. Load for initTableInstanceData, resetTableInstanceData…

TanStack/table · 93 tokens

effect-and-errors

Composing Effect programs, domain errors, HttpError, repository error types, or error propagation at HTTP boundaries.

latitude-dev/latitude-llm · 26 tokens

migrate-better-result-3

Migrate a TypeScript codebase from better-result 2.x to 3.0. Use when upgrading better-result across the TaggedError syntax, removed Result serialization helpers, recovery inference, matching, or retry APIs.

dmmulroy/better-result · 52 tokens

fast-typescript-check

Keep www-sacred's TypeScript fast to type-check and fast to run. Use when touching the ASCII/canvas animation components (the only real per-frame code here), tightening type-check wall-clock, or auditing a change for runtime or compiler regressions. Scoped to this repo — a React 19 / Next.js 16 component library plus…

internet-development/www-sacred · 84 tokens

typescript-magician

Designs complex generic types, refactors any types to strict alternatives, creates type guards and utility types, and resolves TypeScript compiler errors. Use when the user asks about TypeScript (TS) types, generics, type inference, type guards, removing any types, strict typing, type errors, infer, extends…

mcollina/skills · 108 tokens