Compatibility

This page documents what bunpy supports as of v0.10.29 and what it does not. Coverage numbers are updated each release; check the changelog for what changed.

Python version compatibility

bunpy embeds goipy, a Go-native CPython 3.14 interpreter. There is no system Python involved.

Property	Status
Syntax	Python 3.12+ required. f-strings with nested expressions (PEP 701), `match`/`case` (PEP 634), exception groups (PEP 654), `type` aliases (PEP 695) all work.
Semantics	CPython 3.14 target. goipy tracks the 3.14 reference implementation for semantics and standard library behaviour.
Python 2	Not supported and never will be.
Python 3.11 and below	Syntax that was removed or changed in 3.12+ will error.
Type annotations	Supported. PEP 563 (`from __future__ import annotations`) and PEP 649 (lazy annotations, 3.14 default) both work.
C extension modules	Not supported. Packages that require compiled `.so` or `.pyd` extension wheels cannot be imported. Pure-Python wheels work.

If your code runs on CPython 3.12 or 3.13 without C extensions, it will almost certainly run on bunpy with no changes.

Python stdlib coverage

214 of 263 CPython 3.14 stdlib modules are supported as of v0.10.29. The tables below show coverage by category. Modules with partial support have the most commonly-used parts working; the gaps are documented in each module’s page.

Built-in types and core language

Module	Status	Notes
`builtins`	Supported	All built-in functions and types.
`abc`	Supported
`collections`	Supported	All: `deque`, `Counter`, `OrderedDict`, `defaultdict`, `namedtuple`, `ChainMap`.
`collections.abc`	Supported
`dataclasses`	Supported
`enum`	Supported
`functools`	Supported
`itertools`	Supported
`operator`	Supported
`types`	Supported
`typing`	Supported
`typing_extensions`	Partial	Not stdlib; available as a PyPI package.
`weakref`	Supported

Text and string processing

Module	Status	Notes
`re`	Supported
`string`	Supported
`textwrap`	Supported
`unicodedata`	Supported
`difflib`	Supported
`fnmatch`	Supported
`glob`	Supported

File and I/O

Module	Status	Notes
`io`	Supported
`os`	Supported	`os.fork` not available (goroutine model).
`os.path`	Supported
`pathlib`	Supported
`shutil`	Supported
`tempfile`	Supported
`stat`	Supported
`fileinput`	Supported
`csv`	Partial	Reading works; writer missing quoting edge cases. Full support in v0.12.
`configparser`	Partial	Core read/write works; interpolation incomplete. Full support in v0.12.
`zipfile`	Supported
`tarfile`	Supported
`gzip`	Supported
`bz2`	Supported
`lzma`	Supported
`pickle`	Supported
`shelve`	Partial	Full support targeted for v0.12.
`struct`	Supported
`mmap`	Not supported	Requires OS memory-mapping primitives not yet wired in goipy.

Networking

Module	Status	Notes
`socket`	Partial	TCP and UDP sockets work. Unix domain sockets work on macOS and Linux. Raw sockets not supported.
`ssl`	Partial	TLS client connections work. Server-side TLS and client certificate authentication incomplete. Full support in v0.12.
`http.client`	Supported
`http.server`	Supported	Use `bunpy.serve` for production; `http.server` is available for compatibility.
`urllib.request`	Supported
`urllib.parse`	Supported
`email`	Supported
`smtplib`	Supported
`ftplib`	Supported
`imaplib`	Not supported	Low demand; file an issue if you need it.
`poplib`	Not supported	Low demand.
`nntplib`	Not supported	Deprecated in CPython 3.13; will not be added.
`xmlrpc.client`	Supported
`xmlrpc.server`	Supported
`websockets`	Not built-in	Use the `websockets` PyPI package (pure Python). `bunpy.websocket` built-in planned for v0.12.

Data formats and serialization

Module	Status	Notes
`json`	Supported
`xml.etree.ElementTree`	Partial	Basic parsing and serialization work; XPath subset incomplete. Full support in v0.12.
`xml.dom`	Partial
`xml.sax`	Partial
`html`	Supported
`html.parser`	Supported
`base64`	Supported
`hashlib`	Partial	MD5, SHA-1, SHA-256, SHA-512 work. SHA-3 and BLAKE2 variants missing. Full suite in v0.12.
`hmac`	Supported
`binascii`	Supported

Date, time, and math

Module	Status	Notes
`datetime`	Supported
`time`	Supported
`calendar`	Supported
`math`	Supported
`cmath`	Supported
`decimal`	Supported
`fractions`	Supported
`random`	Supported
`statistics`	Supported

Concurrency

Module	Status	Notes
`threading`	Supported	Threads map to goroutines. The GIL does not exist in goipy; actual parallelism is available.
`asyncio`	Supported	Event loop, coroutines, tasks, `asyncio.gather`, `asyncio.sleep`, streams.
`concurrent.futures`	Supported	`ThreadPoolExecutor` and `ProcessPoolExecutor` both work.
`multiprocessing`	Partial	`Process`, `Queue`, `Pipe` work. Shared memory (`multiprocessing.shared_memory`) not yet supported.
`queue`	Supported
`subprocess`	Supported

Databases

Module	Status	Notes
`sqlite3`	Partial	Wired to `bunpy.sqlite` internally. Full parity with CPython’s `sqlite3` targeted for v0.12.
`dbm`	Not supported

Development and introspection

Module	Status	Notes
`sys`	Supported	`sys.platform`, `sys.argv`, `sys.path`, `sys.version`, `sys.exit`, and most others. `sys.settrace` and `sys.setprofile` work (used by the coverage tool).
`inspect`	Supported
`traceback`	Supported
`warnings`	Supported
`logging`	Supported
`unittest`	Supported	All of `unittest` works. `bunpy test` is preferred but not required.
`pdb`	Partial	Basic breakpoint and stepping. TUI line-editor not available in all terminals.
`profile` / `cProfile`	Supported
`dis`	Supported	Disassembles to goipy’s internal bytecode format, not CPython bytecode.
`ast`	Supported
`tokenize`	Supported
`importlib`	Supported	`importlib.import_module`, `importlib.util`, `importlib.resources` all work.

GUI and multimedia (not supported)

tkinter, turtle, idlelib, curses, readline, ossaudiodev, winsound – these modules are permanently out of scope. bunpy is a server-side runtime. If you need a GUI, use a separate Python install.

Platform support

Platform	Architecture	Status	Notes
macOS	arm64 (Apple Silicon)	Supported	Primary development platform.
macOS	x86_64	Supported	Tested on every release.
Linux	x86_64	Supported	Tested in CI.
Linux	arm64	Supported	Tested in CI; used for AWS Graviton and Raspberry Pi deployments.
Windows	x86_64	Supported	PowerShell install, GitHub Actions tested.
Windows	arm64	Not supported	No demand signal yet. File an issue if you need it.
FreeBSD	any	Not supported

All platforms receive binary releases on every tagged commit starting from v0.10.29.

Bun API coverage

bunpy exposes a subset of the Bun global APIs. The goal is not full compatibility with Bun’s JavaScript API surface – it is to give Python code the same ergonomic primitives that make Bun pleasant to use.

Globals

Global	Status	Notes
`fetch`	Supported	Full WHATWG Fetch API. Returns a `Response` with `.text()`, `.json()`, `.bytes()`, `.status`, `.headers`, `.ok`.
`AbortController`	Supported
`AbortSignal`	Supported	`AbortSignal.timeout(ms)` supported.
`URL`	Supported	WHATWG URL standard.
`URLSearchParams`	Supported
`TextEncoder` / `TextDecoder`	Supported
`setTimeout` / `setInterval`	Supported	Available in async contexts and in `bunpy.serve` handlers.
`clearTimeout` / `clearInterval`	Supported
`console`	Supported	`console.log`, `console.error`, `console.warn`, `console.time`, `console.timeEnd`.
`crypto`	Partial	`crypto.randomUUID()` and `crypto.getRandomValues()` work. SubtleCrypto not yet available.
`performance`	Partial	`performance.now()` works. `performance.mark` and `performance.measure` not yet available.

Bun namespace

API	Status	Notes
`Bun.serve(options)`	Supported	Available via `from bunpy.serve import serve`. The `Bun.serve` spelling is also accepted.
`Bun.file(path)`	Supported	Returns a lazy file handle. `.text()`, `.json()`, `.bytes()`, `.stream()`, `.size`, `.type`.
`Bun.write(path, data)`	Supported	Writes a string, bytes, or `Bun.file` to disk.
`Bun.spawn(cmd)`	Supported	Spawns a subprocess. `.stdout`, `.stderr`, `.stdin` are streams. `.exited` is an awaitable.
`Bun.which(name)`	Supported	Resolves an executable name to its full path.
`Bun.env`	Supported	Dict-like access to environment variables.
`Bun.version`	Supported	Returns the bunpy version string.
`Bun.hash(data)`	Supported	Wyhash of a string or bytes.
`Bun.sleep(ms)`	Supported	Awaitable sleep. `await Bun.sleep(100)`.
`Bun.gc()`	Supported	Triggers a GC cycle on the goipy heap.
`Bun.inspect(value)`	Supported	Pretty-prints any value to a string, similar to `repr` but richer.
`Bun.build(options)`	Not supported	JavaScript bundler API; not applicable to Python.
`Bun.plugin(plugin)`	Not supported	JavaScript plugin system; not applicable.
`Bun.websocket`	Not supported	Planned for v0.12 via `bunpy.websocket`.
`Bun.sql`	Not supported	Planned for v0.12 via `bunpy.sqlite`.

What is intentionally absent

Some Bun APIs exist specifically because JavaScript/TypeScript has module systems and compilation models that do not apply to Python. Bun.Transpiler, Bun.resolveSync, import.meta, and the --preload mechanism have no Python equivalent. They are absent by design, not by oversight.

Roadmap Performance