Rent-Free Solana Programs

The Light SDK pays rent-exemption for PDAs, token accounts, and mints. Program logic stays mostly untouched.

Rent cost (per account)	Solana / SPL	Light SDK
Token account	~2,000,000 lamports	~11,000 lamports
Avg. DeFi pool	~$2	~$0.02

Workflow

1. Clarify intent
   • Recommend plan mode, if it's not activated
   • Use AskUserQuestion to resolve blind spots
   • All questions must be resolved before execution
2. Identify references and skills
   • Match task to domain references below
   • Locate relevant documentation and examples
3. Write plan file (YAML task format)
   • Use AskUserQuestion for anything unclear — never guess or assume
   • Identify blockers: permissions, dependencies, unknowns
   • Plan must be complete before execution begins
4. Execute
   • Use Task tool with subagents for parallel research
   • Subagents load skills via Skill tool
   • Track progress with TodoWrite
5. When stuck: spawn subagent with Read, Glob, Grep, DeepWiki MCP access and load skills/ask-mcp

Domain References

Audience	Reference
Anchor pattern	references/anchor.md
Pinocchio pattern	references/pinocchio.md
Client SDK (LightProgramInterface)	references/client-sdk.md
Testing	references/testing.md
CPI instructions	references/instructions.md
SPL to Light comparison	references/spl-to-light.md
FAQ	references/faq.md
Router integration	references/router.md

When to use which

Criteria	Anchor	Pinocchio
Framework	anchor-lang 0.31, #[light_program] macro	pinocchio 0.9, LightProgramPinocchio derive
State struct	Option<CompressionInfo> + LightAccount derive	CompressionInfo (non-optional) + bytemuck::Pod + Zeroable + #[repr(C)]
Account creation	#[light_account(init, ...)] attribute or CreateTokenAccountCpi	CreateTokenAccountCpi, CreateMints batch pattern
Compress/decompress handlers	Auto-generated by #[light_program] macro	Route ProgramAccounts::COMPRESS_ACCOUNTS_IDEMPOTENT etc. in entrypoint
Program ID constant	Not needed (macro derives it)	pub const ID: Pubkey = pubkey_array!(...) + LIGHT_CPI_SIGNER required
Dependencies	light-sdk, light-sdk-macros, light-token, light-anchor-spl	light-account-pinocchio, light-token-pinocchio, bytemuck

DeFi integration

For DeFi programs (AMMs, lending, vaults): the Anchor and Pinocchio patterns above apply directly. DeFi-specific references:

Task	Reference
Router/aggregator integration (cold account loading)	references/router.md
LightProgramInterface trait (client SDK for routers)	references/client-sdk.md

Hot vs Cold Model

After extended inactivity (multiple epochs without writes), accounts auto-compress to cold state. Programs only interact with hot accounts. Clients load cold accounts back on-chain via create_load_instructions.

	Hot (active)	Cold (inactive)
Storage	On-chain	Compressed
Latency	Normal	+0-200ms
Tx size	Normal	+100-2400 bytes
CU	Normal	+15k-400k CU
Program code	No change	No change

The hot path has zero overhead.

External References

Resource	Link
Anchor AMM reference	cp-swap-reference
Pinocchio swap reference	pinocchio-swap
Anchor counter (rent-free PDA)	basic-macros/counter
Pinocchio counter (zero-copy PDA)	pinocchio/counter

SDK references

Package	Link
light-sdk	docs.rs
light-sdk-macros	docs.rs
light-sdk-pinocchio	docs.rs
light-token	docs.rs
light-token-pinocchio	docs.rs
light-account-pinocchio	docs.rs
light-token-client	docs.rs
light-client	docs.rs
light-program-test	docs.rs

Security

This skill does not pull, store, or transmit external secrets. It provides code patterns, documentation references, and development guidance only.

• No credentials consumed. The skill requires no API keys, private keys, or signing secrets. env: [] is declared explicitly.
• User-provided configuration. RPC endpoints, wallet keypairs, and authentication tokens (Privy, wallet adapters) are configured in the user's own application code — the skill only demonstrates how to use them.
• Install source. npx skills add Lightprotocol/skills installs from the public GitHub repository (Lightprotocol/skills). Verify the source before running.
• Subagent scope. This skill may spawn read-only subagents that use Read, Glob, and Grep to search the local repository. Restrict the working directory to your project.
• Audited protocol. Light Protocol smart contracts are independently audited. Reports are published at github.com/Lightprotocol/light-protocol/tree/main/audits.