Stellar Smart Contract Developer - DeFi Execution Layer - Freelance

Location: Remote (with occasional meetings in Paris)
Start: August 2025
Duration: 3-4 months project-based contract

Introduction to the Ecosystem

Are you ready to build critical infrastructure for the next generation of DeFi on Stellar? As liquidity management becomes increasingly complex across decentralized exchanges, we need sophisticated execution layers that can bridge advanced algorithms with on-chain operations.

At Lobster Protocol, we're developing a comprehensive liquidity optimization solution funded by the Stellar Community Fund. Our data-driven approach analyzes DEX pools in real-time, identifying optimal strategies for liquidity providers. We've already built successful solutions across Arbitrum and BNB Chain, and now we're bringing our expertise to Stellar's growing ecosystem.

This is your opportunity to build the smart contract infrastructure that will transform how liquidity flows through Stellar DEXs. You'll create the critical execution layer that connects our proven optimization algorithms with on-chain operations, directly impacting capital efficiency across the ecosystem.

Why Lobster?

The Stellar ecosystem presents a unique opportunity with its built-in DEX, native multi-asset support, and efficient consensus mechanism. Unlike EVM chains, Stellar offers native order books and path payments, enabling sophisticated liquidity strategies without the overhead of complex smart contracts.

Our solution leverages these Stellar-specific advantages while adding an intelligent optimization layer through Soroban smart contracts. By combining Stellar's native efficiency with advanced algorithms, we're creating infrastructure that couldn't exist on other chains.

Build Soroban Smart Contracts:
Develop WASM-compiled smart contracts using Rust and the Soroban SDK. Implement secure validation for liquidity operations including XLM and token deposits/withdrawals. Create contracts that interface with Stellar's native DEX and handle path payments efficiently. Ensure proper integration with Stellar's account and trustline system.

Develop Stellar Integration Layer:
Build the infrastructure to connect our off-chain algorithms with Soroban contracts via Horizon API and Soroban RPC. Implement transaction building and signing mechanisms that respect Stellar's sequence number requirements. Handle Stellar-specific operations like trustline management and path payment optimization.

Optimize for Stellar's Architecture:
Design contracts that minimize storage costs on Stellar's ledger. Implement efficient data structures considering Stellar's fee model. Ensure contracts work seamlessly with Stellar's native multi-asset support and built-in DEX functionality. Optimize for Stellar's 5-second block time.

Deploy to Stellar Network:
Handle deployment through Stellar's testnet (Futurenet for Soroban) with comprehensive testing. Execute mainnet deployment following Stellar Foundation recommendations. Configure proper network settings and monitor contract performance using Stellar-specific tools.

Programming Skills:

• Rust (mandatory): Expert-level proficiency with Soroban SDK for smart contract development
• Experience with WASM compilation and optimization
• Familiarity with Stellar SDKs (JavaScript, Python, or Go) for off-chain integration
• Understanding of asynchronous programming patterns

Stellar Ecosystem Knowledge:

• Proven experience deploying Soroban smart contracts on Stellar testnet/mainnet
• Deep understanding of Stellar's account model and native asset system
• Experience with Horizon API and Soroban RPC endpoints
• Knowledge of Stellar's fee structure and transaction optimization
• Understanding of Stellar DEX architecture (order books, liquidity pools)
• Familiarity with Stellar-specific tools (Stellar Laboratory, Freighter wallet)

Soroban Development:

• RESTful API design for Horizon and Soroban RPC integration
• Transaction builder patterns for Stellar operations
• Experience with Stellar's XDR (External Data Representation) format
• Stellar-specific error handling and retry mechanisms

Security & Best Practices:

• Soroban contract security patterns and anti-patterns
• Understanding of WASM security considerations
• Experience with Stellar's authorization model
• Knowledge of storage optimization on Stellar's ledger

Nice to Have:

• Experience with Stellar anchors and issued assets
• Contributions to Stellar ecosystem projects
• Familiarity with Phoenix, Soroswap, or other Stellar DEXs
• Experience with Stellar's SDEX (native decentralized exchange)
• Knowledge of other WASM-based smart contract platforms

Personal Requirements:

• At least one production Stellar/Soroban project deployed
• Strong autonomy with ability to work from specifications
• Excellent problem-solving and debugging skills
• Clear communication for technical discussions
• Fluent in English (written and spoken)
• Available for initial onboarding call and regular progress updates

• Work on a project leveraging Stellar's unique features (native DEX, multi-asset support)
• Build infrastructure specifically designed for Stellar's efficient architecture
• Collaborate with a team bringing cross-chain expertise to Stellar
• Contribute to Stellar's growing DeFi ecosystem with SCF backing
• Create solutions that utilize Stellar's low fees and fast finality
• Potential to shape liquidity management standards on Stellar
• Direct impact on Stellar DEX efficiency and adoption