talks/2026-nih-bids2.0.html at master · con/talks · GitHub

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<!doctype html>

<html>
	<head>
		<meta charset="utf-8">
		<meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no">

		<!-- Edit me start! -->
		<title>BIDS 2.0</title>
		<meta name="description" content="NIMH Data Science & Sharing Team Lunch & Learn. BIDS 2.0: the past, present, and (realistic) future of the Brain Imaging Data Structure. What 1.x delivered, what 2.0 will and won't change, and how to weigh in.">
		<meta name="author" content=" Yaroslav O. Halchenko ">
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			<div class="slides">


<!-- Start of slides -->
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  Skeleton for the NIMH L&L "BIDS 2.0" talk.
  Slides numbered to match the table in 2026-nih-bids2.0/talk-plan.md.
  Fill in each section's body once content is settled.
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<!-- ============================================================ -->
<!-- Slide 1: Title                                                -->
<!-- ============================================================ -->
<section>
  <section>
    <a href="http://centerforopenneuroscience.org/"><img data-src="pics/con-ccn-dartmouth-letterhead.svg" style="height:150px;"></a>
    <h1 style="margin-top:0;margin-bottom:0.1em;">BIDS 2.0</h1>
    <p style="margin-top:0.3em;margin-bottom:0.3em;font-size:0.75em;font-style:italic;">
      <strong>The past, present, and (realistic) future of the Brain Imaging Data Structure</strong>
    </p>

    <div style="margin-top:0.3em;text-align:center">
      <table style="border:none;">
        <tr>
          <td>
            Yaroslav O. Halchenko<br/>
            <small><a href="https://twitter.com/yarikoptic" target="_blank"><img data-src="pics/twitter.png" style="height:30px;margin:0px"/>@yarikoptic</a></small>
            <small><a href="https://fosstodon.org/@yarikoptic" target="_blank"><img data-src="pics/mastodon-icon.svg" style="height:30px;margin:0px;margin-right:0.1em"/>@yarikoptic@fosstodon.org</a></small>
          </td>
          <td></td>
        </tr>
        <tr>
          <td>
            <small><br/>
              <a href="http://centerforopenneuroscience.org/" target="_blank">Center for Open Neuroscience</a><br/>
              <a href="https://pbs.dartmouth.edu/" target="_blank">Department of Psychological and Brain Sciences</a><br/>
              <a href="http://www.dartmouth.edu" target="_blank">Dartmouth College, NH, USA</a>
            </small>
            <img style="width:160px; margin: 0px" data-src="pics/2026-nih-bids2.0-qrcode.png"/>
          </td>
          <td></td>
        </tr>
      </table>
    </div>

    <small>
      <strong>NIMH Data Science &amp; Sharing Team &mdash; Lunch &amp; Learn &mdash; June 2nd 2026</strong><br/>
      <!-- TODO: insert exact date, room/Zoom link, pre-talk blurb from organisers -->
      Live slides/<a href="https://datasets.datalad.org/centerforopenneuroscience/talks/.git">Sources</a>:
      <a href="https://datasets.datalad.org/centerforopenneuroscience/talks/2026-nih-bids2.0.html">https://datasets.datalad.org/centerforopenneuroscience/talks/2026-nih-bids2.0.html</a>
    </small>
    <br/>
    <small>
      <a href="http://datalad.org" target="_blank"><img style="height:100px;margin:15px" data-src="pics/datalad_D.svg"/></a>
      <a href="http://neuro.debian.net" target="_blank"><img style="height:100px;margin:15px" data-src="pics/neurodebian.png"/></a>
      <a href="http://repronim.org" target="_blank"><img style="height:100px;margin:15px" data-src="pics/repronim-logo-vertical.svg"/></a>
      <a href="https://open-brain-consent.readthedocs.io" target="_blank"><img style="height:100px;margin:15px" data-src="pics/OBC_LogoCheck.svg"/></a>
  	  <a href="https://github.com/myyoda/myyoda" target="_blank"> <img  style="height:100px;margin:15px" data-src="pics/yoda.svg"/></a>
      <a href="https://dandiarchive.org" target="_blank"><img style="height:100px;margin:15px" data-src="pics/dandi-logo-square.svg"/></a>
      <a href="https://bids.neuroimaging.io/" target="_blank"><img style="height:100px;margin:15px" data-src="pics/BIDS_Logo.png"/></a>
      <a href="https://standforukraine.com/" target="_blank"><img style="height:100px;margin:15px" data-src="pics/Ukrainian_Blue-Yellow_ribbon.svg"/></a>
    </small>

    <!-- TODO: STAMPED banner in footer once asset wiring is decided.
         Asset path candidate: assets/stamped/ver-3/name-banner_ver-3.svg -->
  </section>
</section>


<!-- ============================================================ -->
<!-- Slide 2: Who I am / what CON does                             -->
<!-- ============================================================ -->
<section data-transition-speed="zoom">

  <section>
  <img style="height:800px" data-src="pics/yarik-goal.svg"/>
  </section>

<!--  <section>
	<h1>Who am I?</h1>
	<img style="height:400px" data-src="pics/borrowed/twitter-unsolicited-advice.png"/>
  </section> -->

  <section>
	<h3>Brief Bio</h3>
	<p>Born in Siberia (RSFSR, USSR), Grew up in Ukraine, Matured in U.S.A.</p>
	<ul style="font-size:120%">
	  <li class="fragment"><b>-1994 Physics Mathematics Gymnasium #17 (Ukraine):</b><br>
		<small> Regional&State Physics and Programming
		  competitions. MS-DOS. Borland Pascal</small></li>

	  <li class="fragment"><b>-1999 VSTU (Ukraine):
		  <span style="float:right;">Masters in Opto-Electronic Engineering</span></b><br>
		<small> (@yarikoptic). State Physics and International ACM Programming
		  competitions. Spine diagnostic apparatus. Member of "Small Academy of Science of
		  Ukraine". SPIE. Soros Fellowship (twice). MS-DOS/Windows.
		  Borland Pascal, Delphi, VBA
	  </small></li>

	  <li class="fragment"><b>-2003 University of New Mexico:
		  <span style="float:right;">Masters in Computer Science</span></b><br>
		<small><a href="http://www.bcl.hamilton.ie/~barak/">B.Pearlmutter</a>.
		  SOBI/JADE ICA for single trial MEG. Favorite course: Data structures
		  and algorithms.
		  <a href="https://debian.org">Debian GNU/Linux</a>.
		  C, Matlab, shell. CVS
	  </small></li>

	  <li class="fragment"><b>-2009 Rutgers-Newark/NJIT:
		  <span style="float:right;">Ph.D. in Computer Science</span></b><br>
		<small><a href="http://rubic-web.rutgers.edu/people.html">S.Hanson</a>.
		  <a href="http://dx.doi.org/10.1162/neco.2007.09-06-340">fMRI decoding (RFE SVM)</a>.
		  <a href="https://link.springer.com/article/10.1385/NI:2:1:071?noAccess=true">RUMBA</a>.
		  HPC sysadmin (cfengine, PBS).
		  <a href="https://www.fz-juelich.de/SharedDocs/Personen/INM/INM-7/EN/Hanke_m.html">M.Hanke</a>.
		  Debian pkg-exppsy (for FSL and PyEPL).
		  <a href="https://nm.debian.org/person/yoh/">Official Debian developer</a>.
		  <a href="https://arxiv.org/abs/1307.2150">fMRI/EEG (TRANS)fusion</a>.
		  <a href="http://pymvpa.org">PyMVPA</a>.
		  C++, Python. SVN, GIT. 1 wife, 3 kids
	  </small></li>
	  <li class="fragment"><b>- NOW Dartmouth College, PBS Department: <br>
		  <span style="float:right;">Postdoc, Scientist, Research Assistant/Associate/<emph>null</emph> Professor</span></b><br>
		<small><a href="https://haxbylab.dartmouth.edu/">J.Haxby</a>.
		  <a href="http://pymvpa.org">PyMVPA</a>
		  (<a href="http://dx.doi.org/10.1016/j.neuron.2011.08.026">Hyperalignment</a>,
		  ...),
		  <a href="https://neuro.debian.net">NeuroDebian</a>,
		  <a href="https://datalad.org">DataLad</a>,
		  <a href="https://repronim.org">ReproNim</a>,
		  <a href="https://dandiarchive.org">DANDI</a>,
		  <a href="https://stamped-principles.org">STAMPED</a>,
		  ...
		  1 dog, 2 cats, <a href="https://github.com/yarikoptic/coop">Chicken Coop (12 chickens, 1 rooster)</a>,
		  ...
		  <a href="https://www.distribits.live/">distribits</a>,
		  <a href="https://centerforopenneuroscience.org/">CON</a>:
		</small>
	  </li>
	</ul>

	<aside class="notes"><ul>
		<li>Russian Soviet Federative Socialist Republic</li>
	</ul></aside>

  </section>

  <section>
	<div class="r-stack">
	  <img style="width:2000px" data-src="pics/con-webshot-20150812-front-up.png"/>
	  <!-- TODO update this compilation! prepend with proper Ack-->
	  <!-- <img class="fragment" style="width:1000px" data-src="pics/con-ack-bmbf.png"/> -->
	  <img class="fragment" data-src="pics/borrowed/con-webshot-20150812-front-down.png"/>
	  <img class="fragment" style="width:2000px" data-src="pics/con-principles.png"/>
	  <img class="fragment" style="width:2400px" data-src="pics/con-projects-standards-20260601.png"/>
	  <!-- <img class="fragment" style="width:500px"
				data-src="pics/con-ack-joeybenetc-extended.svg"/> -->
	</div>
  </section>

</section>


<!-- ============================================================ -->
<!-- Slide 3: Very brief overview of BIDS and its history         -->
<!-- ============================================================ -->
<section>

  <section  data-transition="slide">
	<img style="width:2000px" data-src="pics/bids-logo-wide.png"/>
	<br>
	<small>
	  <a href="https://www.nature.com/articles/sdata201644">
		Gorgolewski, K. J., Auer, T., Calhoun, V. D., Craddock, R. C., Das, S., Duff,
		E. P., Flandin, G., Ghosh, S. S., Glatard, T., <b>Halchenko, Y. O.</b>, Handwerker,
		D. A., Hanke, M., Keator, D., Li, X., Michael, Z., Maumet, C., Nichols, B. N.,
		Nichols, T. E., Pellman, J., Poline, J.-B., Rokem, A., Schaefer, G., Sochat, V.,
		Triplett, W., Turner, J. A., Varoquaux, G., and Poldrack, R. A. (<b>2016</b>). The
		brain imaging data structure, a format for organizing and describing outputs
		of neuroimaging experiments. Scientific Data, 3:160044</a>
	</small>
  </section>

  <section
	data-background-iframe="pics/bids-10th-birthday-card.html"
	data-background-interactive>
  </section>

  <section  data-transition="slide">
	<h3>BIDS Features</h3>

	<table style="border:none; width:120%;">
	  <tr style="vertical-align:middle;">
		<td style="width:30%; text-align:center;vertical-align:middle">
		  <img style="max-width:100%;" data-src="pics/borrowed/dicom2bids-justbids.png" alt="DICOMs reorganized into a BIDS dataset"/>
		</td>
		<td style="width:70%; text-align:left;">
		  <ul style="font-size:0.7em;">
			<li><strong>Modular composition</strong>
			  <ul><li>related: YODA &rarr;
			  now <a href="https://stamped-principles.org/">STAMPED</a>
			  principles (more later)</li></ul>
			</li>
			<li><strong><a href="https://bids-specification.readthedocs.io/en/stable/common-principles.html#filesystem-structure">Consistent folder composition</a></strong>
			  <ul><li><code><a href="https://bids-specification.readthedocs.io/en/stable/common-principles.html#study-dataset">[study/]</a>&lt;dataset&gt;/sub-&lt;label&gt;/[ses-&lt;label&gt;/]&lt;datatype&gt;/</code></li>
				<li><b>You have seen one BIDS dataset -- you have seen them all!</b></li>

			  </ul>
			</li>
			<li><strong>Expressive file naming schema</strong>
			  <ul>
				<li>related:
				  <a href="http://www2.stat.duke.edu/~rcs46/lectures_2015/01-markdown-git/slides/naming-slides/naming-slides.pdf"><em>Naming Things</em></a> by Jenny Bryan;
				  <a href="https://djnavarro.net/slides-project-structure/#1"><em>Project structure</em></a> by Danielle Navarro;
				  DataLad RDM Course &mdash;
				  <a href="https://psychoinformatics-de.github.io/rdm-course/02-structuring-data/index.html#how-to-name-a-file">How to name a file</a></li>
			  </ul>
			</li>
			<li><strong>Standard file formats</strong>
			  <ul><li>NIfTI / TSV / JSON / EDF / BrainVision / &hellip; per modality (see <a href="https://bids-specification.readthedocs.io/en/stable/">spec</a>)</li></ul>
			</li>
			<li><strong>Documented metadata</strong>
			  <ul><li><a href="https://bids-specification.readthedocs.io/en/stable/common-principles.html#key-value-files-dictionaries">JSON sidecars</a> + <a href="https://bids-specification.readthedocs.io/en/stable/common-principles.html#tabular-files">TSV "summaries"</a> + <a href="https://bids-specification.readthedocs.io/en/stable/common-principles.html#the-inheritance-principle">inheritance principle</a></li></ul>
			</li>
			<li><strong>Human- and machine-readable data</strong>
			  <ul>
				<li>Human-readable <a href="https://bids-specification.readthedocs.io/">specification</a> (Markdown &rarr; HTML / PDF)</li>
				<li>Machine-readable <a href="https://github.com/bids-standard/bids-specification/tree/master/src/schema">schema</a> (YAML) &mdash; validator, docs, and tooling generated from it</li>
				<li><a href="https://bids-apps.neuroimaging.io/apps/">BIDS-apps</a> (such as mriqc, fmriprep, etc) for turnkey pipelines</li>
				<li><a href="https://github.com/bids-standard/pybids">PyBIDS</a>, <a href="https://github.com/childmindresearch/bids2table/">bids2table</a>, <a href="https://github.com/khanlab/snakebids">snakebids</a> etc. for scripting</li>

			  </ul>
			</li>
			<li><strong>Constant evolution</strong>
			  <ul><li>via <a href="https://bids.neuroimaging.io/extensions/">BIDS Extension Proposals (BEPs)</a> and open
				<a href="https://github.com/bids-standard/bids-specification/pulls">PR review</a></li></ul>
			</li>
		  </ul>
		</td>
	  </tr>
	</table>

	<p style="text-align:right;margin-top:0.3em;"><small>
	  See deeper overview at <a href="https://docs.google.com/presentation/d/1x-LdlVGItyX6oINm8URIP5cZWBvQG6bM/edit?usp=sharing&ouid=106463979469591360865&rtpof=true&sd=true">"The Brain Imaging Data Structure (BIDS): an open community standard for neuroscience"</a>,<br/> NSF POSE Workshop 2024
	</small></p>
  </section>

  <section  data-transition="slide">
	<img style="width:2000px" data-src="pics/borrowed/bids-timeline-2024.svg"/>
	<br>
	<p style="text-align:right;margin-top:0.3em;">
	<small>
	  From: <b>The past, present, and future of the brain imaging data structure (BIDS)</b><br/>
	  By Poldrack et al. Imaging Neuroscience (2024) 2: 1–19.
	  <a href="https://doi.org/10.1162/imag_a_00103">DOI: 10.1162/imag_a_00103</a><br/>
	  More of historical intro: <a href="https://docs.google.com/presentation/d/1doDm2wo8JyZrzuG8a2Xk-5OlBlzwq9I3/edit?usp=sharing&ouid=106463979469591360865&rtpof=true&sd=true"><b>MRITogether: Roads to BIDS</b></a> talk slides.
	</small>
	</p>
  </section>

</section>

<!-- ============================================================ -->
<!-- Slide 4: Intro BIDS 2.0         -->
<!-- ============================================================ -->

<section>
  <section data-markdown  data-separator="^\n----\n" data-vertical="^\n---\n">
	<textarea data-template>

## The Future of BIDS

<small>

> As BIDS nears its tenth anniversary, its success has also led to increasing recognition of the limitations of the existing framework. This has, in turn, driven a growing discussion regarding the need for a new major version of BIDS (“BIDS 2.0”) that would introduce changes that are incompatible with the existing BIDS framework. A dedicated repository (https://github.com/bids-standard/bids-2-devel/issues) is collecting issues, a subset of which will be chosen for BIDS 2.0. It is likely that the discussion of a new version will continue over the next few years, given the significant difficulty that breaking changes would impose on tool developers.

</small>

<p style="text-align:right;margin-top:0.3em;">
	<small>
	  From: <b>The past, present, and future of the brain imaging data structure (BIDS)</b><br/>
	  By Poldrack et al. Imaging Neuroscience (2024) 2: 1–19.
	  <a href="https://doi.org/10.1162/imag_a_00103">DOI: 10.1162/imag_a_00103</a><br/>
	</small>
</p>

----

### Standards vs software - the wrinkle

- In software, adding a feature is a *minor* semver bump. Users opt in or ignore
- In a standard, even an *optional* addition pulls on **every tool**:
  - similar to DICOM - takes long for manufacturers to adopt
  - validators, parsers, and pipelines diverge silently
  - **example**: refining inheritance for TSVs:
    - spec moves, tools don't
    - datasets become "valid by spec, invalid by behavior"
- Implication for BIDS 2.0:
  - **bundle breaking changes into one release with migration support**

----

## Originally: more ambitious BIDS 2.0 (INCF 2024 poster)

[![IMG](pics/bids-2.0-incf2024-webshottop.png)](https://docs.google.com/presentation/d/189tCRORhhn1ZzN6DmtK_Wqneui-kaoGiPXh7nzI0WGU/edit?usp=sharing)

----

## Current reduced agenda

[![IMG](pics/borrowed/bids-2-devel_issue57-agenda_20260602.png)](https://github.com/bids-standard/bids-2-devel/issues/57)

----

# BIDS 2.0 Goals

## Deprecate the Deprecated
## Improve Consistency
## Facilitate Modularity

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# Deprecations

----

### BIDS 1.x has already broken things many times

Across `1.0 → 1.11` the spec already accumulated:

- **~9 metadata fields** still marked `level: deprecated` in the schema
- **3 suffix / enum values** carried forward as back-compat shims
- **1 column value** (`"89+"` in `participants.tsv` now just `89`)

The mechanism: [`bids-specification#634`](https://github.com/bids-standard/bids-specification/pull/634) ([1.4.1](https://github.com/bids-standard/bids-specification/releases/tag/v1.4.1), 2020-10) formalized `DEPRECATED` as a *permanent* schema category — validators SHOULD warn; fields stay in the spec.

(claude'd summary [`2026-nih-bids2.0/notes-1x-deprecations.md`](https://github.com/con/talks/blob/master/2026-nih-bids2.0/notes-1x-deprecations.md))

----

### Field renames — same value, different key

- `Unit` → `Units` ([`#773`](https://github.com/bids-standard/bids-specification/pull/773), [1.6.0](https://github.com/bids-standard/bids-specification/releases/tag/v1.6.0))
- `ElektaNeuromag` → `NeuromagElektaMEGIN` ([1.8.0](https://github.com/bids-standard/bids-specification/releases/tag/v1.8.0))
- `MISCChannelCount` → `MiscChannelCount` (camelCase fix, [1.8.0](https://github.com/bids-standard/bids-specification/releases/tag/v1.8.0))
- `orientation_component` → `component` in `channels.tsv` ([`#1417`](https://github.com/bids-standard/bids-specification/pull/1417), [1.9.0](https://github.com/bids-standard/bids-specification/releases/tag/v1.9.0))
- `atlas` entity → `seg` ([`#1579`](https://github.com/bids-standard/bids-specification/pull/1579), [1.9.0](https://github.com/bids-standard/bids-specification/releases/tag/v1.9.0))
- `ManufacturersCapModelName` → `CapManufacturer` + `CapManufacturersModelName` (1.1.1)
- Anatomical suffixes `T2star` / `FLASH` / `PD` → `T2starw` + parametric variants ([`#725`](https://github.com/bids-standard/bids-specification/pull/725), [1.5.0](https://github.com/bids-standard/bids-specification/releases/tag/v1.5.0))

→ every consumer keying off the old name silently fails.

----

### Semantic swap under a stable name — the worst kind

- `IntendedFor`, `Sources`, `AssociatedEmptyRoom` paths → **BIDS URIs** ([`#918`](https://github.com/bids-standard/bids-specification/pull/918), [1.8.0](https://github.com/bids-standard/bids-specification/releases/tag/v1.8.0)): consumers expecting POSIX paths now also see `bids::sub-…`.
- `index` numeric semantics churned **twice** on whether `0` is a valid run ([`#535`](https://github.com/bids-standard/bids-specification/pull/535) → [`#590`](https://github.com/bids-standard/bids-specification/pull/590) → [`#1482`](https://github.com/bids-standard/bids-specification/pull/1482)).
- Inheritance principle — **value overloading** flagged as discouraged in [1.10.1](https://github.com/bids-standard/bids-specification/releases/tag/v1.10.1), explicit plan to deprecate in 2.0 ([`#1834`](https://github.com/bids-standard/bids-specification/pull/1834)).

----

### MAY → MUST tightenings (previously-valid datasets can fail)

- `events.tsv` MUST be sorted by `onset` ([`#1732`](https://github.com/bids-standard/bids-specification/pull/1732), [1.10.0](https://github.com/bids-standard/bids-specification/releases/tag/v1.10.0))
- `electrodes.tsv` clarified REQUIRED for iEEG ([`#1896`](https://github.com/bids-standard/bids-specification/pull/1896), [1.10.1](https://github.com/bids-standard/bids-specification/releases/tag/v1.10.1))
- `recording` entity REQUIRED for PET / blood ([`#1005`](https://github.com/bids-standard/bids-specification/pull/1005), [1.7.0](https://github.com/bids-standard/bids-specification/releases/tag/v1.7.0))
- `dataset_description.Authors` RECOMMENDED ([`#1092`](https://github.com/bids-standard/bids-specification/pull/1092), [1.7.0](https://github.com/bids-standard/bids-specification/releases/tag/v1.7.0))
- Bare DOIs deprecated → fully-specified URIs (`common-principles.md`)
- "No blank/duplicate TSV headers" clarification ([`#1116`](https://github.com/bids-standard/bids-specification/pull/1116)) — a *de facto* validator tightening, not flagged as breaking.

----

### Carried forward as `deprecated` in the schema

[![IMG](pics/borrowed/bids-deprecated-suffixes_20260602.png)](https://bids-specification.readthedocs.io/en/stable/modality-specific-files/magnetic-resonance-imaging-data.html#deprecated-suffixes)

----

## Takeaway

### BIDS 2.0 is the chance to **drop the shims**

- BIDS has effectively been making breaking changes for years

- BIDS 2.0 isn't the first break -- it's the first one we get to
  get rid of "garbage DNA"

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# Inconsistencies

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### Inconsistencies to tidy in 2.0

- `participants.tsv` → `subjects.tsv` — match the `sub-` entity name
- Singular TSV column names ([`bids-specification#1821`](https://github.com/bids-standard/bids-specification/issues/1821)) — `Units` (singular), etc.
- Inheritance Principle "Summarization": RECOMMENDED → **MUST**
- Formalize principle(s) reflecting overall consistency:
  - singular index column (e.g. `session_id`) in `.tsv` files ([`bids-specification#2283`](https://github.com/bids-standard/bids-specification/issues/2283))
  - outlier: composite index in `samples.tsv` ([`bids-specification#2273`](https://github.com/bids-standard/bids-specification/issues/2273))
- **Time units across modalities** — fMRI uses seconds, three ASL fields use milliseconds ([`bids-2-devel#96`](https://github.com/bids-standard/bids-2-devel/issues/96))
- **`.json` sidecars mix two purposes** - file-level metadata *and* TSV column-definition dictionaries — different consumers, same schema namespace
  - inconsistency between `.tsv` and `.tsv.gz` ([`bids-2-devel#71`](https://github.com/bids-standard/bids-2-devel/issues/71))
- **Path-vs-URI** for cross-file references — BIDS URIs ([1.8.0](https://github.com/bids-standard/bids-specification/releases/tag/v1.8.0)) coexist with legacy raw-relative paths in the wild

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### Composite-index outlier &mdash; `samples.tsv`

[![IMG](pics/borrowed/bids-issues-2273-composite-index_20260602.png)](https://github.com/bids-standard/bids-specification/issues/2273)
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# Modularity

----

### Modularity

BIDS [v1.10.1](https://github.com/bids-standard/bids-specification/releases/tag/v1.10.1) (2025-09-03) **already** introduced "study" `DatasetType`:

[![IMG](pics/borrowed/bids-studydataset-1.11.1.png)](https://bids-specification.readthedocs.io/en/v1.11.1/common-principles.html#study-dataset)

Originally ([`bids-2-devel#59`](https://github.com/bids-standard/bids-2-devel/issues/59))

----

#### many existing layouts generalize well into BIDS "study"

<div style="position: relative; width: 100%; height: 90vh;">

<img src="pics/bids-nipoppy.png" class="" width="80%" style="position: absolute; top: 3%; left: 0%" />
<img src="pics/bids-princeton.png" class="fragment fade-in" width="80%" style="position: absolute; top: 8%; left: 5%" />
<img src="pics/bids-yoda.png" class="fragment fade-in" width="80%" style="position: absolute; top: 13%; left: 10%" />

</div>

----
### OpenNeuroStudies: even higher modularization (in BIDS 3.0)

[![IMG](pics/openneuro-studies-webshot_20260602.png)](https://github.com/OpenNeuroStudies/OpenNeuroStudies)

----

### Higher Modularity postponed (until BIDS 3.0)

[![IMG](pics/borrowed/bids-2-devel_issue54-flex_20260602.png)](https://github.com/bids-standard/bids-2-devel/issues/54)

----

### YODA: from raw data to paper

<!-- .slide: data-transition="fade" -->

![ReproNim/containers workflow](pics/yoda-hierarchy-with-containers.png)

Watch **YODA: Structure your studies, observable and reproducible they become** ReproNim Webinar:
[slides](https://datasets.datalad.org/centerforopenneuroscience/talks/2026-repronim-YODA-BIDS-webinar.html#/) and [Video on ReproTube](https://datasets.datalad.org/repronim/ReproTube/web/#/channel/ReproNim/video/1XbTbJ_P2x0?tab=local&wide=1&t=5&q=BIDS&filter=1)

----

## YODA →

[![IMG](pics/stamped-principles-webshot_20260602.png)](https://stamped-principles.org/)

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## Now: BIDS 2.0 HOW/WHERE (weigh in!)

- Overall "BIDS-2.0" PR — [`bids-specification#1775`](https://github.com/bids-standard/bids-specification/issues/1775)
- Inheritance principle deep-dive — [`bids-specification#2155`](https://github.com/bids-standard/bids-specification/issues/2155) (Lestropie)

- **Tooling:**
  - Users: [`bids-utils migrate`](https://github.com/bids-standard/bids-utils/)
  - BIDS developers:
    - functional patches in [`bids-specification#1775`](https://github.com/bids-standard/bids-specification/pull/1775)
    - extensive testing against [bids-examples](https://github.com/bids-standard/bids-examples)
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<!-- Slide 14: How to get involved                                 -->
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## How to get involved

- BIDS 2.0 Project board: [github.com/orgs/bids-standard/projects/10](https://github.com/orgs/bids-standard/projects/10)
- Repos:
  - [`bids-standard/bids-2-devel`](https://github.com/bids-standard/bids-2-devel)
  - [`bids-specification`](https://github.com/bids-standard/bids-specification)
  - [`bids-utils`](https://github.com/bids-standard/bids-utils)
  - [`bids-examples`](https://github.com/bids-standard/bids-examples):
    - contribute more valid examples/use-cases to secure **your** future!
- PRs - no change is "too small"
- BEP process - new modalities & large additions are moving forward: review!
- Use/contribute to Zotero group bibliography: [zotero.org/groups/5111637/bids](https://www.zotero.org/groups/5111637/bids/library)

<!-- TODO: add QR codes for project board, bids-2-devel, BIDS.bib Zotero, monthly call -->

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<!-- Slide 15: Acknowledgments + Q&A                               -->
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## Acknowledgments & Q&A

- [BIDS maintainers and contributors](https://bids.neuroimaging.io/collaboration/contributors.html)
- [Funders](https://bids.neuroimaging.io/collaboration/acknowledgments.html)

- Questions?

<!-- TODO: optional discussion-prompt slide before Q&A -->

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