Python SDK changelog

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Latest

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1.3.4 (2026-02-23)

sb = modal.Sandbox.create(app=app)
snapshot = sb.snapshot_directory("/project")

sb2 = modal.Sandbox.create(app=app)
sb2.mount_image("/project", snapshot)

• Added modal.Sandbox.detach() method to disconnect your local client from the Sandbox and clean up resources
• modal.Sandbox.terminate() now accepts a wait parameter (default False)
• Throughput for writing to the stdin of a modal.Sandbox.exec process has been increased by 8x
• Added modal.Volume.from_id() method for referencing a Volume by its object id

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1.3.3 (2026-02-12)

• Added modal billing report CLI and promoted modal.billing.workspace_billing_report API to General Availability for Team and Enterprise plan workspaces
• Added modal.Queue.from_id() and modal.Dict.from_id() methods
• Modal’s async usage warnings are now enabled by default when using blocking interfaces in async contexts
  • Can be disabled with MODAL_ASYNC_WARNINGS=0 or async_warnings = false in .modal.toml
• Fixed bug where ASGI scope’s state contents could leak between requests when using @modal.asgi_app

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1.3.2 (2026-01-30)

• Modal objects now have a .get_dashboard_url() method
• New modal dashboard CLI and modal app dashboard / modal volume dashboard subcommands
• Example:
  fc = f.spawn()
  print(fc.get_dashboard_url())  # Easy access to logs, etc.
  

• Can now pass a Sandbox ID (sb-xxxxx) directly to modal container logs CLI
• modal token info CLI now includes the token name
• Fixed issue where modal.Cls.with_options() could sometimes use stale argument values when called repeatedly

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1.3.1 (2026-01-22)

• Improved experimental support for Python 3.14t (free-threaded Python) inside Modal containers
• Container environment now uses the Python implementation of the Protobuf runtime
• Use modal.Image.from_registry("debian:bookworm-slim", add_python="3.14t") for 3.14t images
• Only available on 2025.06 Image Builder Version

• Can now provide a custom_domain for a modal.Sandbox
• Added modal token info CLI command
• Added --timestamps flag to modal run, modal serve, modal deploy, and modal container logs
• Automatic CLI creation for modal run now supports Literal type annotations
• Fixed bug that could cause App builds to fail with uninformative CancelledError
• Improved client resource management when running modal.Sandbox.exec

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1.3.0 (2025-12-19)

• Modal SDK will no longer propagate grpclib.GRPCError types; use modal.Error subtypes instead
• max_inputs parameter renamed to single_use_containers (now takes boolean instead of integer)
• Async (.aio) interface deprecated from modal.FunctionCall.from_id, modal.Image.from_id, and modal.SandboxSnapshot.from_id
• replace_bytes and delete_bytes methods removed from modal.file_io filesystem interface
• Images built with modal.Image.micromamba() using 2023.12 Image Builder Version now match local Python version by default

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1.2

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1.2.6 (2025-12-16)

• Fixed bug where iterating on a modal.Sandbox.exec output stream could raise unauthenticated errors

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1.2.5 (2025-12-12)

• Can now set a custom name= for a Function without using serialized=True
• Can now start modal shell with a Modal Image ID (modal shell im-abc123)
• modal shell now warns if you pass invalid combinations of arguments
• Fixed bug in modal shell that caused vi to fail with unicode decode errors
• Fixed thread-safety issue in modal.Sandbox resource cleanup
• Improved performance when adding large local directories to an Image
• Improved async Sandbox performance by not blocking the event loop while reading from stdout or stderr

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1.2.4 (2025-11-21)

• Fixed bug in modal.Sandbox.exec when using stderr=StreamType.STDOUT (introduced in v1.2.3)
• Added h2_enabled option in modal.forward, which enables HTTP/2 advertisement in TLS establishment

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1.2.3 (2025-11-20)

@app.function(nonpreemptible=True)
def f():
    pass

• Modal client can now respond gracefully to server throttling with automatic retries (controlled by MODAL_MAX_THROTTLE_WAIT config)
• modal.Sandbox.exec implementation rewritten for improved reliability and efficiency
• Added --add-local flag to modal shell
• Fixed bug where some Modal objects weren’t usable after being captured in a Memory Snapshot

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1.2.2 (2025-11-10)

cache_vol = modal.Volume.from_name("cache-mount")
cmd_using_cache = "..."
image = modal.Image.debian_slim().run_commands(cmd_using_cache, volumes={"/cache": cache_vol})

• All Modal objects now accept an optional modal.Client object in their constructor methods
• Sandbox name= parameter now required to follow Modal object naming rules
• modal.CloudBucketMount now supports force_path_style=True
• Output from modal config show is now valid JSON
• Fixed bug where App tags were not attached to Image builds

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1.2.1 (2025-10-22)

• Can override the default -dev suffix for ephemeral Apps via dev_suffix field in .modal.toml or MODAL_DEV_SUFFIX environment variable
• Fixed bug where reading long stdout/stderr from modal.Sandbox.exec() could break in text=True mode
• Fixed bug where status code was not checked when downloading a file from a Volume
• modal run --detach ... now exits more gracefully if you lose internet connection

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1.2.0 (2025-10-09)

app = modal.App("llm-inference-server", tags={"team": "genai-platform"})

• Added modal.Sandbox.create_connect_token() for HTTP/Websocket authentication
• Added modal.Image.build() method to eagerly trigger Image builds
• Added env parameter to multiple methods for configuring environment variables
• Can now pass modal.CloudBucketMount to modal.Cls.with_options
• Added modal.Sandbox.get_tags() method
• modal.Dict.pop() now accepts optional default parameter
• Can now modal shell into a running Sandbox by passing its Sandbox ID
• Sandboxes can be configured to expose a PTY device via pty=True
• Added modal.experimental.image_delete() function
• Using modal run --interactive now suppresses Modal’s status spinner
• Improved support for Protobuf 5+

• Deprecated client parameter from Sandbox.set_tags()
• Deprecated pty_info parameter from Sandbox.create() and Sandbox.exec()
• Replaced --no-confirm with --yes in modal environment delete CLI

• Required to instantiate a modal.Cls before invoking methods
• Removed eager .lookup() method from most Modal object classes
• Removed public constructors on modal.mount.Mount object
• Removed context_mount= parameter from Docker-oriented modal.Image methods
• Removed allow_cross_region_volumes parameter from function decorators
• Removed modal.experimental.update_autoscaler() function

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1.1

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1.1.4 (2025-09-03)

• Added startup_timeout parameter to @app.function() and @app.cls() decorators
• Added optional idle_timeout parameter to modal.Sandbox.create()
• Added cluster_id field to modal.experimental.get_cluster_info() dataclass
• When block_network=True in modal.Sandbox.create(), now raises error if port parameters are also set
• Functions decorated with @modal.asgi_app() now return HTTP 408 instead of 502 for input timeout

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1.1.3 (2025-08-19)

• Fixed bug from v1.1.2 affecting modal.FunctionCall methods when object is retrieved via modal.FunctionCall.from_id
• Added retries to improve robustness of modal volume get

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1.1.2 (2025-08-14)

modal.Volume.objects.create("huggingface-cache", environment_name="dev")

modal.Secret.objects.delete("aws-token")

for queue in modal.Queue.objects.list():
    queue_info = queue.info()
    print(queue_info.name, queue_info.created_at, queue.len())

• modal.Cls.with_options now supports region and cloud keyword arguments
• Fixed bug that could cause Image builds to fail with 'FilePatternMatcher' object has no attribute 'patterns'
• Fixed bug where rdma=True was ignored when using @modal.experimental.clustered() with a modal.Cls

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1.1.1 (2025-08-01)

sb = modal.Sandbox.create(name="my-sandbox")
sb2 = modal.Sandbox.from_name(app, "my-sandbox")  # Must be unique within app

• Internal change to modal.Image.uv_pip_install for better portability (requires rebuild)
• Added .name property and .info() method to modal.Dict, modal.Queue, modal.Volume, and modal.Secret
• Sandboxes now support experimental_options configuration
• Improved Modal’s rich output in Jupyter notebooks

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1.1.0 (2025-07-17)

import modal

# uv_pip_install: up to 50% faster than pip_install
image = modal.Image.debian_slim().uv_pip_install("torch==2.7.1", "numpy==2.3.1")

# uv_sync: uses pyproject.toml and uv.lock files
image = modal.Image.debian_slim().uv_sync()

• Optimized handling of ignore parameter in Image.add_local_dir
• Added poetry_version parameter to modal.Image.poetry_install_from_file
• Added modal.Sandbox.reload_volumes method
• Added build_args parameter to modal.Image.from_dockerfile
• Can now use @modal.experimental.clustered and i6pn networking with modal.Cls
• Fixed bug where Cls.with_options would fail with already-hydrated modal.Secret
• Fixed bug where Sandbox exec timeout was not respected by ContainerProcess.wait() or poll()
• Fixed retry handling when using modal run --detach

• Now raise modal.exception.NotFoundError in all cases where Modal object lookups fail
• Enforcing pre-1.0 deprecations on modal.build, modal.Image.copy_local_file, and modal.Image.copy_local_dir
• Deprecating environment_name parameter in modal.Sandbox.create()
• Deprecated namespace parameter in .from_name methods

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1.0

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1.0.5 (2025-06-27)

vol = modal.Volume.from_name("models")
read_only_vol = vol.read_only()

@app.function(volumes={"/models": read_only_vol})
def f():
    with open("/models/weights.pt", "w") as fid:  # Raises an OSError
        ...

• Introduced gradual fix for bug where Function.map and Function.starmap leak modal.exceptions.UserCodeException when return_exceptions=True
  • Set wrap_returned_exceptions=False to opt into future behavior
• Parameterized class inheritance now properly handles modal.parameter() annotations from parent classes
• Modal client now retries initial connection to Modal server

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1.0.4 (2025-06-13)

• Multiple calls to modal.Cls.with_options now merge overrides
• Added --secret option to modal shell
• Added verbose: bool option to modal.Sandbox.create()
• Updated modal.Sandbox.watch() so exceptions are raised in calling task

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1.0.3 (2025-06-05)

@app.function(schedule=modal.Cron("* 6 * * *"), timezone="America/New_York")
def f():
    print("This function will run every day at 6am New York time.")

• Added h2_ports parameter to Sandbox.create for HTTP/2 encrypted ports
• Added --from-dotenv and --from-json options to modal secret create
• Sandbox.terminate no longer waits for container shutdown by default
• Improved performance and stability for modal volume get
• Fixed rare race condition in Function.map
• Fixed issue where Function.map would stall for 55 seconds with empty iterator

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1.0.2 (2025-05-26)

• Fixed incompatibility with breaking changes in aiohttp v3.12.0

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1.0.1 (2025-05-19)

• Added --timestamps flag to modal app logs
• Fixed bug where objects from Sandbox.list had returncode == 0 for running Sandboxes
• Fixed bug affecting systems where sys.platform.node includes unicode characters

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1.0.0 (2025-05-16)

• Removed modal.Mount as a public object and various mount= parameters
• Removed show_progress parameter from modal.App.run (use modal.enable_output context manager)
• Passing flagged options to Image.pip_install package list now raises error (use extra_options)
• Removed backwards compatibility for label= or tag= keywords in object lookup methods
• Generator Functions can no longer be invoked with Function.spawn
• Removed .resolve() method on Modal objects (use .hydrate())
• Functions decorated with @modal.asgi_app or @modal.wsgi_app now required to be nullary
• Referencing modal.Stub now raises AttributeError (renamed to modal.App)