Weights & Biases Migration

The wandb compatibility shim is in public preview. Its interface and behavior may change as we iterate. Expect sharp edges.

We’ve created a Weights & Biases compatibility layer that enables dual-logging to both wandb and Pluto simultaneously. This allows you to gradually migrate your experiment tracking without touching existing training scripts.

Quick Start

Install Pluto and authenticate. Use either pluto login (stores a token in your system keyring — recommended for interactive workstations) or export PLUTO_API_KEY (recommended for CI / containers / non-interactive jobs):

pip install pluto-ml

# Pick ONE of the two lines below:
pluto login                          # interactive — stores token in keyring
export PLUTO_API_KEY=mlps_xxx        # or set the env var

Then run any existing wandb script — dual-logging activates automatically:

import wandb

# Project that the run is recorded to
project = "my-awesome-project"

# Dictionary with hyperparameters
config = {
    'epochs': 10,
    'lr': 0.01,
}

with wandb.init(project=project, config=config) as run:
    # Training code here
    # Log values to W&B with run.log()
    run.log({"accuracy": 0.9, "loss": 0.1})

That’s it. Every wandb.log() call now also logs to Pluto. No PLUTO_PROJECT env var needed — the shim picks up the project= kwarg from wandb.init().

Configuration

Authentication

Either of the following is sufficient — the hook checks both:

Source	When to use
`pluto login`	Interactive workstations. Stores a token in your system keyring; persists across shells.
`PLUTO_API_KEY` env var	CI, containers, or any non-interactive context. In `DISABLE_WANDB_LOGGING=true` mode, `WANDB_API_KEY` may be reused as a Pluto token.

If neither is present, the shim logs a one-time warning pointing at pluto login / PLUTO_API_KEY and wandb runs unmodified.

Project Name

Resolved in this order (first match wins):

Source	Notes
`PLUTO_PROJECT` env var	Highest precedence.
`project=` kwarg to `wandb.init(...)`	Picked up automatically — no extra config needed.
`WANDB_PROJECT` env var	Falls back to wandb’s own project env so you don’t need to duplicate config.
`run.project` attribute on the wandb run	Last-resort fallback.

Optional Environment Variables

Variable	Description
`PLUTO_URL_APP`	App endpoint for self-hosted instances
`PLUTO_URL_API`	API endpoint for self-hosted instances
`PLUTO_URL_INGEST`	Ingest endpoint for self-hosted instances
`DISABLE_WANDB_LOGGING`	Set to `true` to skip wandb entirely and only log to Pluto (post-sunset mode, see below).

Supported Operations

The compatibility layer monkey-patches wandb.init() so the returned Run object dual-logs every supported call. Unsupported methods still work normally on wandb via attribute fallthrough — they just don’t dual-log to Pluto.

Initialization

wandb	pluto
`wandb.init(project="my-project", config=cfg)`	`pluto.init(project="my-project", config=cfg)`
`wandb.init(group="my-sweep")` / `WANDB_RUN_GROUP`	Surfaced as a `group:my-sweep` tag
`wandb.init(job_type="train")` / `WANDB_JOB_TYPE`	Surfaced as a `job_type:train` tag
`wandb.init(fork_from=...)`	`pluto.init(fork_run_id=..., fork_step=...)`
`run.tags = ["experiment-v1"]`	`run.add_tags(["experiment-v1"])`

wandb.init() completes fully before any Pluto code runs. pluto.init() runs in a thread with a 10s timeout — if the Pluto server is unreachable, the run silently falls back to wandb-only. Tag assignments on the wandb run sync to Pluto on every assignment.

Metric Logging

wandb	pluto
`wandb.log({"train/loss": 0.5})`	`run.log({"train/loss": 0.5})`
`wandb.log({"train/loss": 0.5}, step=100)`	`run.log({"train/loss": 0.5}, step=100)`

Numeric values, lists of numbers, and the wandb media types below are forwarded to Pluto. The data dict you pass into wandb.log() is never mutated.

Media Logging

wandb	pluto equivalent
`wandb.Image(...)`	`pluto.Image(...)`
`wandb.Histogram(...)`	`pluto.Histogram(...)`
`wandb.Audio(...)`	`pluto.Audio(...)`
`wandb.Video(...)`	`pluto.Video(...)`
`wandb.Table(...)`	Pluto table file

Lists of media at the same step (wandb.log({"gens": [wandb.Image(a), wandb.Image(b)]})) are forwarded as a multi-sample group. The Pluto UI renders these with a per-card ◀ i / N ▶ nav — see Images: Multi-Sample Logging.

Artifacts and Saved Files

wandb	pluto equivalent
`wandb.log_artifact(art)`	Each local file in the artifact → `pluto.Artifact` under `artifacts/{art_name}/{entry_path}`
`wandb.save(path_or_glob)`	Each matched file → `pluto.Artifact` under `save/{basename}`

Reference entries (S3 URLs, etc.) inside wandb.Artifact are skipped — Pluto stores files directly. Artifact versions and aliases are not translated; Pluto has no equivalent.

Finish

wandb.finish() triggers pluto.finish() as well. Pluto’s teardown has a 5s timeout so it never blocks wandb’s cleanup. If pluto.init() failed earlier, the run stays wandb-only and finish() is a no-op on the Pluto side.

Not Supported

These wandb features run normally on wandb but do not dual-log to Pluto:

wandb feature	Reason
`run.config.update()` post-init	Compat layer captures config only at `wandb.init()`. Call `run.update_config()` directly on the Pluto run for in-run updates.
`run.watch()` (gradient tracking)	No Pluto equivalent.
`wandb.log_model()` / model registry	No Pluto equivalent.
`wandb.log_code()`	No Pluto equivalent.
`define_metric()`, `mark_preempting()`, sweeps	No Pluto equivalent.

Post-Sunset Mode

When you’re ready to stop sending data to wandb, set the kill switch:

export DISABLE_WANDB_LOGGING=true

In disabled mode, WANDB_API_KEY can also hold a Pluto API token, so a user fully migrating from wandb can swap a single env var value:

export WANDB_API_KEY=mlps_xxx       # Pluto token in the existing var
export WANDB_PROJECT=my-project
export DISABLE_WANDB_LOGGING=true
python train.py

All wandb.* calls are intercepted and redirected to Pluto without any code changes.

Get Started

Core

API Reference

Integrations

Migrate

Changelog

Quick Start

Configuration

Authentication

Project Name

Optional Environment Variables

Supported Operations

Initialization

Metric Logging

Media Logging

Artifacts and Saved Files

Finish

Not Supported

Post-Sunset Mode

​Quick Start

​Configuration

​Authentication

​Project Name

​Optional Environment Variables

​Supported Operations

​Initialization

​Metric Logging

​Media Logging

​Artifacts and Saved Files

​Finish

​Not Supported

​Post-Sunset Mode

Quick Start

Configuration

Authentication

Project Name

Optional Environment Variables

Supported Operations

Initialization

Metric Logging

Media Logging

Artifacts and Saved Files

Finish

Not Supported

Post-Sunset Mode