gatsbyjs/gatsby · error · Error

A plugin tried to update a node field that it doesn't own:

Error message

A plugin tried to update a node field that it doesn't own:

Node id: ${node.id}
Plugin: ${plugin.name}
name: ${name}
value: ${value}

What it means

createNodeField enforces single-owner semantics per field: the first plugin to set a given field name on a node is recorded in node.internal.fieldOwners[schemaFieldName], and any later createNodeField call for that same schema field from a different plugin throws. This prevents two plugins from silently clobbering each other's extension data on the same node. The schemaFieldName strips any ___NODE suffix so foreign-key fields share ownership with their scalar counterpart.

Source

Thrown at packages/gatsby/src/redux/actions/public.js:936

  actionOptions?: ActionOptions
) => {
  // Ensure required fields are set.
  if (!node.internal.fieldOwners) {
    node.internal.fieldOwners = {}
  }
  if (!node.fields) {
    node.fields = {}
  }

  // Normalized name of the field that will be used in schema
  const schemaFieldName = _.includes(name, `___NODE`)
    ? name.split(`___`)[0]
    : name

  // Check that this field isn't owned by another plugin.
  const fieldOwner = node.internal.fieldOwners[schemaFieldName]
  if (fieldOwner && fieldOwner !== plugin.name) {
    throw new Error(
      stripIndent`
      A plugin tried to update a node field that it doesn't own:

      Node id: ${node.id}
      Plugin: ${plugin.name}
      name: ${name}
      value: ${value}
      `
    )
  }

  // Update node
  node.fields[name] = value
  node.internal.fieldOwners[schemaFieldName] = plugin.name
  node = sanitizeNode(node)

  return {
    ...actionOptions,

View on GitHub (pinned to 8b06340921)

Solutions

Rename the field your plugin writes so it does not collide (e.g. `myPluginSlug` instead of `slug`).
If you legitimately own the field, ensure only one plugin calls createNodeField for that name; consolidate the logic.
If you are replacing another plugin's behavior, disable/remove that plugin or use a different node type.
Check the error's Plugin + name to see which two plugins conflict, then adjust ownership in config.

Example fix

// before - plugin 'gatsby-source-x' and 'gatsby-source-y' both do:
createNodeField({ node, name: `slug`, value: raw.slug })
// after - namespace per plugin
createNodeField({ node, name: `xSlug`, value: raw.slug })

Defensive patterns

Strategy: validation

Validate before calling

// Check ownership before calling createNodeField.
function safeCreateNodeField(actions, { node, name, value, pluginName }) {
  const schemaName = name.includes('___NODE') ? name.split('___')[0] : name
  const owner = node.internal.fieldOwners?.[schemaName]
  if (owner && owner !== pluginName) {
    // skip or rename instead of throwing
    actions.createNodeField({ node, name: `${pluginName}_${name}`, value })
    return
  }
  actions.createNodeField({ node, name, value })
}

Type guard

function canOwnField(node, name, pluginName) {
  const schemaName = name.includes('___NODE') ? name.split('___')[0] : name
  const owner = node?.internal?.fieldOwners?.[schemaName]
  return !owner || owner === pluginName
}

Prevention

Namespace field names with your plugin name to avoid collisions.
Coordinate field ownership across plugins in your project config.
Avoid generic field names like 'slug', 'title', 'excerpt' in shared transformers.

When it happens

Trigger: Calling actions.createNodeField({ node, name, value }) from plugin B when node.internal.fieldOwners[name] (or [name.split('___')[0]]) was already set to plugin A.name, with A.name !== B.name. Fires inside the createNodeField action creator before the ADD_FIELD_TO_NODE action is dispatched.

Common situations: Two transformer/source plugins both writing the same field name (e.g. both set `slug` or `excerpt`) on shared node types; a custom plugin reusing a field name that gatsby-transformer-remark or another transformer already owns; copy-pasting field-extension code across plugins.

Related errors

AI-assisted analysis of gatsbyjs/gatsby@8b06340921 (2026-08-13). Data as JSON: /api/errors/a6cd677c956df062. Report an issue: GitHub.