py-stellar-base

The Python Stellar SDK provides APIs to build transactions, query Horizon, and interact with Soroban RPC, with implementations of several Stellar Ecosystem Proposals.


Category	SDKs
Website	https://stellar-sdk.readthedocs.io
Repository	https://github.com/StellarCN/py-stellar-base
First Released	October 2016
Intake	soft-launch
Budget Requested	15000

Project Description

py-stellar-base is a Python library for building Stellar applications. It provides transaction building, Horizon API access, Soroban RPC support, high-level Soroban smart contract support, and implements several Stellar Ecosystem Proposals. The SDK is distributed via PyPI (stellar-sdk) and listed on the official Stellar developer documentation.

py-stellar-base is one of the most popular SDKs in the Stellar ecosystem, used by organizations including SDF, Lobstr, and Trezor. Its accessibility makes it a common first choice for developers new to Stellar, lowering the barrier to entry for the broader ecosystem.

Team & Experience

overcat (GitHub: overcat, Discord: @overcat.me) has been active in the Stellar community since 2018 and has rich experience in Stellar-related development, maintaining a series of Stellar infrastructure software. Currently maintained Stellar-related projects are listed at https://lightsail.network.

Retroactive Impact

In Q2 2026, all three planned deliverables were completed, and protocol work went beyond the plan. The SDK shipped three stable releases (14.0.0 through 14.1.1). Support for the smart-contract self-description SEPs (SEP-46, SEP-47, SEP-48) and an AI coding agent skill both landed in 14.1.0. stellar_sdk.auth was redesigned so any account contract can authorize Soroban entries, and the generated XDR was advanced from the planned Protocol 26 to Protocol 27, with CAP-71 Soroban authorization support implemented in the 15.0.0-beta0 pre-release. Alongside features, the toolchain was modernized, migration to ruff, parallelized CI, and network-free test mocks, and dependencies kept current.

Past Deliverables

2026 Q2

1. Continuous Maintenance and Improvement

Description from last quarter:

Regular SDK updates addressing Horizon, Soroban RPC, and protocol changes (including Protocol 26), bug fixes, feature requests, and documentation updates. Keep CI/CD pipelines, SBOM workflow, and dependency updates current.

Proof of completion:

Release 14.0.0: https://github.com/StellarCN/py-stellar-base/releases/tag/14.0.0
Release 14.1.0: https://github.com/StellarCN/py-stellar-base/releases/tag/14.1.0
Release 14.1.1: https://github.com/StellarCN/py-stellar-base/releases/tag/14.1.1
Pre-release 15.0.0-beta0: https://github.com/StellarCN/py-stellar-base/releases/tag/15.0.0-beta0

Some notable PR, not exhaustive:

PR #1189: https://github.com/StellarCN/py-stellar-base/pull/1189 — feat: add CAP-71 (Protocol 27) Soroban authorization support
PR #1199: https://github.com/StellarCN/py-stellar-base/pull/1199 — test: migrate from aioresponses to aiointercept for aiohttp 3.14 support
PR #1188: https://github.com/StellarCN/py-stellar-base/pull/1188 — feat: add simulateTransaction authV2 flag
PR #1177: https://github.com/StellarCN/py-stellar-base/pull/1177 — Migrate to ruff, PR 2
PR #1176: https://github.com/StellarCN/py-stellar-base/pull/1176 — Migrate to ruff, PR 1
PR #1172: https://github.com/StellarCN/py-stellar-base/pull/1172 — test: replace real network requests with local httpserver mocks
PR #1167: https://github.com/StellarCN/py-stellar-base/pull/1167 — test: use local httpbin fixture in tests
PR #1162: https://github.com/StellarCN/py-stellar-base/pull/1162 — feat: improve stellar_sdk.contract.AssembledTransaction authorization lifecycle for contract account authorization
PR #1160: https://github.com/StellarCN/py-stellar-base/pull/1160 — feat!: redesign stellar_sdk.auth so any account contract can authorize Soroban entries
View all 37 merged PRs (Q2 2026): https://github.com/StellarCN/py-stellar-base/pulls?q=is%3Apr+is%3Amerged+merged%3A2026-04-01..2026-06-30

Three stable releases shipped. The generated XDR was upgraded to Protocol 26 and then to Protocol 27, exceeding the planned Protocol 26 target. stellar_sdk.auth was redesigned so any account contract (default Stellar account, BLS, WebAuthn, threshold, etc.) can authorize Soroban entries, and CAP-71 Protocol 27 Soroban authorization — including the new address-bound and delegated credential types — was implemented across the high-level API. This work currently ships in the 15.0.0-beta0 pre-release rather than a stable release: Protocol 27 is not yet broadly available in real-world test environments, so the stable 15.0.0 is intentionally held until the implementation can be validated against a live Protocol 27 network. The toolchain was also modernized with a migration to ruff, parallelized CI, and network-free test mocks, alongside numerous bug fixes and dependency updates.

2. SEP-46, SEP-47, and SEP-48 Support

Description from last quarter:

Add support for SEP-46 (Contract Meta), SEP-47 (Contract Interface Discovery), and SEP-48 (Contract Interface Specification). These three SEPs form the foundation for smart contract self-description: SEP-46 defines how contracts embed metadata in Wasm custom sections, SEP-47 lets contracts declare which SEPs they implement, and SEP-48 provides a rich interface specification including Soroban host types, user-defined types, and event schemas. Together they enable the SDK to parse and expose contract metadata, which is essential for tooling, auto-generated contract clients, and off-chain systems that need to understand contract interfaces.

Proof of completion:

Release 14.1.0: https://github.com/StellarCN/py-stellar-base/releases/tag/14.1.0

Introspection APIs for SEP-46 (contract metadata), SEP-47 (contract interface discovery), and SEP-48 (contract interface specification) were added and shipped in 14.1.0, including ContractMeta, ContractSpec, ContractInfo, and SorobanServer[Async].get_contract_* helpers that parse a Soroban contract’s Wasm and expose its self-described metadata. This gives tooling and off-chain systems a standard way to understand contract interfaces.

3. AI Coding Agent Skill

Description from last quarter:

Publish an AI coding agent skill for py-stellar-base following the agentskills.io open standard, compatible with Claude Code, Codex CLI, Cursor, Gemini CLI, and others. The skill provides token-efficient documentation and best practices for AI-assisted development with the SDK, lowering the barrier for developers using AI tools to build on Stellar.

Proof of completion:

Skill marketplace listing: https://skillsmp.com/creators/stellarcn/py-stellar-base/skills-py-stellar-base — published py-stellar-base agent skill

An Agent Skills-compatible stellar-sdk skill was published — both in the SDK repository and to the skill marketplace — with Claude Code plugin marketplace metadata and topic references covering transactions, Horizon, Soroban, XDR/SCVal, async workflows, SEP integrations, security, and troubleshooting. It gives AI coding assistants token-efficient, accurate guidance for building on Stellar with the SDK, lowering the barrier for developers using AI tools.

Proposed Impact

The primary goal for Q3 2026 is to ship py-stellar-base 15.0.0 as a stable release with full Protocol 27 support, giving the ecosystem’s large Python user base a supported path to the new protocol. CAP-71 Soroban authorization is already implemented in the 15.0.0 beta; the stable release is held until Protocol 27 is available on live test networks for end-to-end validation (issue #1187). Ongoing maintenance continues in parallel.

Proposed Deliverables

1. Release py-stellar-base 15.0.0 with Full Protocol 27 Support

Finalize the 15.0.0 beta into a stable release with complete Protocol 27 support, including CAP-71 Soroban authorization (ADDRESS_V2 and delegated ADDRESS_WITH_DELEGATES credentials). The implementation is already done in beta; the remaining work, validating against a live Protocol 27 network, auth examples and a migration guide for the breaking auth changes, and the stable release to PyPI.

Proof: Stable 15.0.0 release on GitHub and PyPI, auth examples and migration notes, passing CI on main.

2. Continuous Maintenance and Improvement

Beyond routine upkeep, responding to community issues and pull requests, tracking Horizon and Soroban RPC changes, and keeping CI/CD, the SBOM workflow, and dependencies current, we want to be candid about our intent for Q3: rather than adding new features, we plan to slow down and look inward. We will audit the codebase for accumulated technical debt, refactor rough edges, and optimize code that has grown organically across many releases, so the SDK stays maintainable and dependable for the long term.

This is a deliberate decision to consolidate, not to coast. For this SDK, “maintenance” has consistently produced meaningful improvements well beyond what we formally plan, Q2 is the clearest example, where full Protocol 27 support, the stellar_sdk.auth redesign, and a toolchain modernization all shipped under this same deliverable. We expect Q3 to be no different: as we dig into the code, concrete fixes and refinements will follow.

Proof: Release notes on GitHub, updated CHANGELOG, refactoring and optimization PRs, passing CI on main.

Metrics loaded from PG Atlas

Legal Acknowledgements

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