diff --git a/CHANGELOG.md b/CHANGELOG.md
index efb44b4..6a8ac73 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 
 * Hook useSaveWithGlobalRewrite() ([#161](https://github.com/i-VRESSE/workflow-builder/pull/161))
+* Support for if/then/else in JSON schema ([#160](https://github.com/i-VRESSE/workflow-builder/pull/160))
 
 ## @i-vresse/wb-core 3.0.1 - 2024-05-23
 
diff --git a/docs/schema.md b/docs/schema.md
index 4e96fc8..55d9adf 100644
--- a/docs/schema.md
+++ b/docs/schema.md
@@ -131,3 +131,27 @@ and `abcd.pdb` file has chain A and B with residues 1, 2, 3 and 4.
 
 Then the form will have restricted the `chain` prop to only allow `A` and `B`
 and will have restricted the sta and end prop to only allow 1, 2, 3 and 4.
+
+## If then else
+
+The `if`, `then` and `else` keywords can be used to [conditionally apply a schema](https://json-schema.org/understanding-json-schema/reference/conditionals#ifthenelse).
+
+For example to have the `foo` property only if the `bar` property is false use:
+
+```yaml
+    type: object
+    properties:
+      bar:
+        type: boolean
+    if:
+      properties:
+        bar:
+          const: true
+    then: {}
+    else:
+      properties:
+        foo:
+          type: string
+```
+
+Only supports simple const condition with one or more properties and not complex conditions like patterns. Also only a single if/tnen/else block per object is supported. It can be combined with [groups](uiSchema.md#uigroup).
diff --git a/packages/core/src/grouper.test.ts b/packages/core/src/grouper.test.ts
index 145e475..1d27e23 100644
--- a/packages/core/src/grouper.test.ts
+++ b/packages/core/src/grouper.test.ts
@@ -1,7 +1,13 @@
-import { expect, describe, it, beforeEach } from 'vitest'
+import { expect, describe, it, beforeEach, assert } from 'vitest'
 import { JSONSchema7 } from 'json-schema'
 import { UiSchema } from '@rjsf/core'
-import { groupCatalog, groupParameters, groupSchema, groupUiSchema, unGroupParameters } from './grouper'
+import {
+  groupCatalog,
+  groupParameters,
+  groupSchema,
+  groupUiSchema,
+  unGroupParameters
+} from './grouper'
 import { ICatalog, IParameters } from './types'
 
 function deepCopy<T> (value: T): T {
@@ -288,18 +294,22 @@ describe('given a schema with a 2 props with ui:group in uiSchema and 1 without'
           schema,
           uiSchema
         },
-        categories: [{
-          name: 'category1',
-          description: 'Category 1'
-        }],
-        nodes: [{
-          schema,
-          uiSchema,
-          id: 'node1',
-          label: 'Node 1',
-          description: 'Description 1',
-          category: 'category1'
-        }],
+        categories: [
+          {
+            name: 'category1',
+            description: 'Category 1'
+          }
+        ],
+        nodes: [
+          {
+            schema,
+            uiSchema,
+            id: 'node1',
+            label: 'Node 1',
+            description: 'Description 1',
+            category: 'category1'
+          }
+        ],
         examples: {}
       }
 
@@ -342,20 +352,24 @@ describe('given a schema with a 2 props with ui:group in uiSchema and 1 without'
           formSchema: expectedSchema,
           formUiSchema: expecteduiSchema
         },
-        categories: [{
-          name: 'category1',
-          description: 'Category 1'
-        }],
-        nodes: [{
-          schema,
-          uiSchema,
-          formSchema: expectedSchema,
-          formUiSchema: expecteduiSchema,
-          id: 'node1',
-          label: 'Node 1',
-          description: 'Description 1',
-          category: 'category1'
-        }],
+        categories: [
+          {
+            name: 'category1',
+            description: 'Category 1'
+          }
+        ],
+        nodes: [
+          {
+            schema,
+            uiSchema,
+            formSchema: expectedSchema,
+            formUiSchema: expecteduiSchema,
+            id: 'node1',
+            label: 'Node 1',
+            description: 'Description 1',
+            category: 'category1'
+          }
+        ],
         examples: {}
       }
       expect(actual).toEqual(expected)
@@ -499,7 +513,9 @@ describe('given a un-grouped prop with same name as group', () => {
         }
       }
 
-      expect(() => groupSchema(schema, uiSchema)).toThrow('Can not have group and un-grouped parameter with same name prop2')
+      expect(() => groupSchema(schema, uiSchema)).toThrow(
+        'Can not have group and un-grouped parameter with same name prop2'
+      )
     })
   })
 })
@@ -633,3 +649,277 @@ describe('given a prop with same name as group and another prop in same group',
     })
   })
 })
+
+describe('given a schema with if/then/else', () => {
+  let schema: JSONSchema7
+  let uiSchema: UiSchema
+
+  describe('else in same group', () => {
+    beforeEach(() => {
+      schema = {
+        type: 'object',
+        properties: {
+          prop1: {
+            type: 'string',
+            enum: ['val1', 'val2']
+          }
+        },
+        additionalProperties: false,
+        if: {
+          properties: {
+            prop1: {
+              const: 'val1'
+            }
+          }
+        },
+        then: {},
+        else: {
+          properties: {
+            prop2: {
+              type: 'string'
+            }
+          }
+        }
+      }
+      uiSchema = {
+        prop1: {
+          'ui:group': 'group1'
+        },
+        prop2: {
+          'ui:group': 'group1'
+        }
+      }
+    })
+
+    describe('groupSchema()', () => {
+      it('should move properties inside an object with group name as key', () => {
+        const groupedSchema = groupSchema(schema, uiSchema)
+
+        const expectedSchema: JSONSchema7 = {
+          type: 'object',
+          properties: {
+            group1: {
+              type: 'object',
+              properties: {
+                prop1: {
+                  type: 'string',
+                  enum: ['val1', 'val2']
+                }
+              },
+              additionalProperties: false,
+              if: {
+                properties: {
+                  prop1: {
+                    const: 'val1'
+                  }
+                }
+              },
+              then: {},
+              else: {
+                properties: {
+                  prop2: {
+                    type: 'string'
+                  }
+                }
+              }
+            }
+          },
+          additionalProperties: false
+        }
+        expect(groupedSchema).toEqual(expectedSchema)
+      })
+    })
+  })
+
+  describe('then in same group', () => {
+    beforeEach(() => {
+      schema = {
+        type: 'object',
+        properties: {
+          prop1: {
+            type: 'string',
+            enum: ['val1', 'val2']
+          }
+        },
+        additionalProperties: false,
+        if: {
+          properties: {
+            prop1: {
+              const: 'val1'
+            }
+          }
+        },
+        then: {
+          properties: {
+            prop2: {
+              type: 'string'
+            }
+          }
+        },
+        else: {}
+      }
+      uiSchema = {
+        prop1: {
+          'ui:group': 'group1'
+        },
+        prop2: {
+          'ui:group': 'group1'
+        }
+      }
+    })
+
+    describe('groupSchema()', () => {
+      it('should move properties inside an object with group name as key', () => {
+        const groupedSchema = groupSchema(schema, uiSchema)
+
+        const expectedSchema: JSONSchema7 = {
+          type: 'object',
+          properties: {
+            group1: {
+              type: 'object',
+              properties: {
+                prop1: {
+                  type: 'string',
+                  enum: ['val1', 'val2']
+                }
+              },
+              additionalProperties: false,
+              if: {
+                properties: {
+                  prop1: {
+                    const: 'val1'
+                  }
+                }
+              },
+              then: {
+                properties: {
+                  prop2: {
+                    type: 'string'
+                  }
+                }
+              },
+              else: {}
+            }
+          },
+          additionalProperties: false
+        }
+        expect(groupedSchema).toEqual(expectedSchema)
+      })
+    })
+  })
+
+  describe.each<{ label: string, schema: JSONSchema7, uiSchema: UiSchema }>([
+    {
+      label: 'if and else in different group',
+      schema: {
+        type: 'object',
+        properties: {
+          prop1: {
+            type: 'string',
+            enum: ['val1', 'val2']
+          }
+        },
+        additionalProperties: false,
+        if: {
+          properties: {
+            prop1: {
+              const: 'val1'
+            }
+          }
+        },
+        then: {
+        },
+        else: {
+          properties: {
+            prop2: {
+              type: 'string'
+            }
+          }
+        }
+      },
+      uiSchema: {
+        prop1: {
+          'ui:group': 'group1'
+        },
+        prop2: {
+          'ui:group': 'group2'
+        }
+      }
+    },
+    {
+      label: 'if and then in different group',
+      schema: {
+        type: 'object',
+        properties: {
+          prop1: {
+            type: 'string',
+            enum: ['val1', 'val2']
+          }
+        },
+        additionalProperties: false,
+        if: {
+          properties: {
+            prop1: {
+              const: 'val1'
+            }
+          }
+        },
+        then: {
+          properties: {
+            prop2: {
+              type: 'string'
+            }
+          }
+        },
+        else: {}
+      },
+      uiSchema: {
+        prop1: {
+          'ui:group': 'group1'
+        },
+        prop2: {
+          'ui:group': 'group2'
+        }
+      }
+    },
+    {
+      label: 'if not in group',
+      schema: {
+        type: 'object',
+        properties: {
+          prop1: {
+            type: 'string',
+            enum: ['val1', 'val2']
+          }
+        },
+        additionalProperties: false,
+        if: {
+          properties: {
+            prop1: {
+              const: 'val1'
+            }
+          }
+        },
+        then: {
+          properties: {
+            prop2: {
+              type: 'string'
+            }
+          }
+        },
+        else: {}
+      },
+      uiSchema: {
+        prop2: {
+          'ui:group': 'group2'
+        }
+      }
+    }
+  ])('$label', ({ schema, uiSchema }) => {
+    it('groupSchema() should throw error', () => {
+      assert.throws(() => {
+        groupSchema(schema, uiSchema)
+      }, 'Cannot have an if in one group and a then/else in another group')
+    })
+  })
+})
diff --git a/packages/core/src/grouper.ts b/packages/core/src/grouper.ts
index 7c1e2e5..3a54a2b 100644
--- a/packages/core/src/grouper.ts
+++ b/packages/core/src/grouper.ts
@@ -18,6 +18,67 @@ import { ICatalog, IParameters } from './types'
 import { JSONSchema7 } from 'json-schema'
 import { isObject } from './utils/isObject'
 
+function groupOfIfProp (schema: JSONSchema7, uiSchema: UiSchema): string | undefined {
+  if (!(schema.if !== undefined &&
+    typeof schema.if !== 'boolean' &&
+    (schema.if.properties != null))) {
+    return undefined
+  }
+  // TODO handle multiple props in schema.if
+  const ifPropName = Object.keys(schema.if.properties)[0]
+  if (ifPropName in uiSchema && 'ui:group' in uiSchema[ifPropName]) {
+    return uiSchema[ifPropName]['ui:group']
+  }
+  return undefined
+}
+
+function groupSchemaCondition ({
+  k,
+  v,
+  group,
+  newSchema,
+  uiSchema,
+  newGroup
+}: {
+  k: string
+  v: UiSchema
+  group: string
+  newSchema: JSONSchema7
+  uiSchema: UiSchema
+  newGroup: JSONSchema7
+}): boolean {
+  // TODO handle when if is in group but then/else is not
+  // now treated as normal prop instead of conditional
+  const elseInGroup =
+    newSchema.else !== undefined &&
+    typeof newSchema.else !== 'boolean' &&
+    (newSchema.else.properties != null) &&
+    k in newSchema.else.properties
+  const thenInGroup =
+    newSchema.then !== undefined &&
+    typeof newSchema.then !== 'boolean' &&
+    (newSchema.then.properties != null) &&
+    k in newSchema.then.properties
+  if (thenInGroup || elseInGroup) {
+    const ifGroup = groupOfIfProp(newSchema, uiSchema)
+    if (ifGroup !== group) {
+      throw new Error(
+        'Cannot have an if in one group and a then/else in another group'
+      )
+    }
+    newGroup.if = newSchema.if
+    newGroup.then = newSchema.then
+    newGroup.else = newSchema.else
+    /* eslint-disable @typescript-eslint/no-dynamic-delete */
+    delete newSchema.if
+    delete newSchema.then
+    delete newSchema.else
+    /* eslint-enable @typescript-eslint/no-dynamic-delete */
+    return true
+  }
+  return false
+}
+
 /**
  * Create new JSON schema where properties marked with same `ui:group` are grouped together into an object.
  *
@@ -41,7 +102,9 @@ export function groupSchema (
     Object.keys(uiSchema).filter((k) => 'ui:group' in uiSchema[k])
   )
   const allProps = new Set(Object.keys(schema.properties ?? {}))
-  const grouplessProps = new Set([...allProps].filter((x) => !propsWithGroup.has(x)))
+  const grouplessProps = new Set(
+    [...allProps].filter((x) => !propsWithGroup.has(x))
+  )
   const grouplessPropsWithSameNameAsGroup = new Set(
     [...grouplessProps].filter((x) => definedGroups.has(x))
   )
@@ -53,12 +116,18 @@ export function groupSchema (
     )
   }
 
-  if (!('properties' in newSchema && typeof newSchema.properties === 'object')) {
+  if (
+    !('properties' in newSchema && typeof newSchema.properties === 'object')
+  ) {
     return newSchema
   }
 
   // prop with group and same name as any group should be nested first
-  const propsWithSameNameAsAnyGroup = new Set(Object.entries(uiSchema).filter(([k, v]) => 'ui:group' in v && definedGroups.has(k)).map((d) => d[0]))
+  const propsWithSameNameAsAnyGroup = new Set(
+    Object.entries(uiSchema)
+      .filter(([k, v]) => 'ui:group' in v && definedGroups.has(k))
+      .map((d) => d[0])
+  )
   for (const k of propsWithSameNameAsAnyGroup) {
     const prop = newSchema.properties[k]
     /* eslint-disable @typescript-eslint/no-dynamic-delete */
@@ -78,7 +147,9 @@ export function groupSchema (
     // TODO recursivly, now only loops over first direct props
     if ('ui:group' in v && !propsWithSameNameAsAnyGroup.has(k)) {
       const group = v['ui:group']
-      if (!('properties' in newSchema && typeof newSchema.properties === 'object')) {
+      if (
+        !('properties' in newSchema && typeof newSchema.properties === 'object')
+      ) {
         throw new Error('Schema must have properties')
       }
       if (!(group in newSchema.properties)) {
@@ -92,6 +163,21 @@ export function groupSchema (
       if (typeof newGroup === 'boolean' || newGroup.properties === undefined) {
         return
       }
+      if (
+        groupSchemaCondition({
+          k,
+          v,
+          group,
+          newSchema,
+          uiSchema,
+          newGroup
+        })
+      ) {
+        // If k was a then or else prop then it is has been moved to the newGroup as if/then/else
+        // no need to move it as property
+        return
+      }
+
       newGroup.properties[k] = newSchema.properties[k]
       // Remove k as it now is in the group
       /* eslint-disable @typescript-eslint/no-dynamic-delete */
diff --git a/packages/core/src/pruner.test.ts b/packages/core/src/pruner.test.ts
index 1e346aa..eaf7e3d 100644
--- a/packages/core/src/pruner.test.ts
+++ b/packages/core/src/pruner.test.ts
@@ -640,4 +640,219 @@ describe('pruneDefaults()', () => {
       expect(result).toStrictEqual(expected)
     })
   })
+
+  describe('if/then/else', () => {
+    describe('given if is true and has else parameter', () => {
+      it('should remove else parameter', () => {
+        const parameters = {
+          prop1: 'val1',
+          prop2: 'someval'
+        }
+        const schema: JSONSchema7 = {
+          type: 'object',
+          properties: {
+            prop1: {
+              type: 'string',
+              enum: ['val1', 'val2']
+            }
+          },
+          if: {
+            properties: {
+              prop1: {
+                const: 'val1'
+              }
+            }
+          },
+          then: {
+          },
+          else: {
+            properties: {
+              prop2: {
+                type: 'string'
+              }
+            }
+          },
+          additionalProperties: false
+        }
+
+        const result = pruneDefaults(parameters, schema, true)
+        const expected = {
+          prop1: 'val1'
+        }
+        expect(result).toStrictEqual(expected)
+      })
+    })
+
+    describe('given if is false and has then parameter', () => {
+      it('should remove then parameter', () => {
+        const parameters = {
+          prop1: 'val2',
+          prop2: 'someval'
+        }
+        const schema: JSONSchema7 = {
+          type: 'object',
+          properties: {
+            prop1: {
+              type: 'string',
+              enum: ['val1', 'val2']
+            }
+          },
+          if: {
+            properties: {
+              prop1: {
+                const: 'val1'
+              }
+            }
+          },
+          then: {
+            properties: {
+              prop2: {
+                type: 'string'
+              }
+            }
+          },
+          else: {
+          },
+          additionalProperties: false
+        }
+
+        const result = pruneDefaults(parameters, schema, true)
+        const expected = {
+          prop1: 'val2'
+        }
+        expect(result).toStrictEqual(expected)
+      })
+    })
+
+    describe('given if is true and has then and else parameter', () => {
+      it('should remove else parameter, but keep then', () => {
+        const parameters = {
+          prop1: 'val1',
+          prop2: 'someval',
+          prop3: 'someval3'
+        }
+        const schema: JSONSchema7 = {
+          type: 'object',
+          properties: {
+            prop1: {
+              type: 'string',
+              enum: ['val1', 'val2']
+            }
+          },
+          if: {
+            properties: {
+              prop1: {
+                const: 'val1'
+              }
+            }
+          },
+          then: {
+            properties: {
+              prop3: {
+                type: 'string'
+              }
+            }
+          },
+          else: {
+            properties: {
+              prop2: {
+                type: 'string'
+              }
+            }
+          },
+          additionalProperties: false
+        }
+
+        const result = pruneDefaults(parameters, schema, true)
+        const expected = {
+          prop1: 'val1',
+          prop3: 'someval3'
+        }
+        expect(result).toStrictEqual(expected)
+      })
+    })
+
+    describe('given if is false and has else parameter which is same as default', () => {
+      it('should remove else parameter', () => {
+        const parameters = {
+          prop1: 'val2',
+          prop2: 'someval'
+        }
+        const schema: JSONSchema7 = {
+          type: 'object',
+          properties: {
+            prop1: {
+              type: 'string',
+              enum: ['val1', 'val2']
+            }
+          },
+          if: {
+            properties: {
+              prop1: {
+                const: 'val1'
+              }
+            }
+          },
+          then: {
+          },
+          else: {
+            properties: {
+              prop2: {
+                type: 'string',
+                default: 'someval'
+              }
+            }
+          },
+          additionalProperties: false
+        }
+
+        const result = pruneDefaults(parameters, schema, true)
+        const expected = {
+          prop1: 'val2'
+        }
+        expect(result).toStrictEqual(expected)
+      })
+    })
+
+    describe('given if is true and has then parameter which is same as default', () => {
+      it('should remove then parameter', () => {
+        const parameters = {
+          prop1: 'val1',
+          prop2: 'someval'
+        }
+        const schema: JSONSchema7 = {
+          type: 'object',
+          properties: {
+            prop1: {
+              type: 'string',
+              enum: ['val1', 'val2']
+            }
+          },
+          if: {
+            properties: {
+              prop1: {
+                const: 'val1'
+              }
+            }
+          },
+          then: {
+            properties: {
+              prop2: {
+                type: 'string',
+                default: 'someval'
+              }
+            }
+          },
+          else: {},
+          additionalProperties: false
+        }
+
+        const result = pruneDefaults(parameters, schema, true)
+        const expected = {
+          prop1: 'val1'
+        }
+        expect(result).toStrictEqual(expected)
+      })
+    })
+  })
 })
diff --git a/packages/core/src/pruner.ts b/packages/core/src/pruner.ts
index 77c408c..1d62bc2 100644
--- a/packages/core/src/pruner.ts
+++ b/packages/core/src/pruner.ts
@@ -72,5 +72,63 @@ export function pruneDefaults (parameters: IParameters, schema: JSONSchema7, res
       newParameters[k] = v
     }
   })
-  return newParameters
+  return pruneThenElses(newParameters, schema)
+}
+
+function pruneThenElses (parameters: IParameters, schema: JSONSchema7): IParameters {
+  if (!(schema.if !== undefined && typeof schema.if !== 'boolean' && schema.if !== undefined && schema.if.properties !== undefined)) {
+    // no if then bail out
+    return parameters
+  }
+
+  const condition = Object.entries(schema.if.properties).every(
+    ([k, sv]) => typeof sv === 'object' && sv.const !== undefined && sv.const === parameters[k]
+  )
+  if (condition) {
+    // Remove else parameters
+    if (schema.else !== undefined && typeof schema.else !== 'boolean' && schema.else !== undefined && schema.else.properties !== undefined) {
+      const elsePropnames = Object.keys(schema.else.properties)
+      for (const k of elsePropnames) {
+        /* eslint-disable @typescript-eslint/no-dynamic-delete */
+        delete parameters[k]
+        /* eslint-enable @typescript-eslint/no-dynamic-delete */
+      }
+    }
+    // Remove then parameters that are same as default
+    if (schema.then !== undefined && typeof schema.then !== 'boolean' && schema.then !== undefined && schema.then.properties !== undefined) {
+      const thenPropnames = Object.keys(schema.then.properties)
+      for (const k of thenPropnames) {
+        const p = schema.then.properties[k]
+        if (typeof p === 'object' && p.default === parameters[k]) {
+          /* eslint-disable @typescript-eslint/no-dynamic-delete */
+          delete parameters[k]
+          /* eslint-enable @typescript-eslint/no-dynamic-delete */
+        }
+      }
+    }
+  } else {
+    // Remove then parameters
+    if (schema.then !== undefined && typeof schema.then !== 'boolean' && schema.then !== undefined && schema.then.properties !== undefined) {
+      const thenPropnames = Object.keys(schema.then.properties)
+      for (const k of thenPropnames) {
+        /* eslint-disable @typescript-eslint/no-dynamic-delete */
+        delete parameters[k]
+        /* eslint-enable @typescript-eslint/no-dynamic-delete */
+      }
+    }
+    // Remove else parameters that are same as default
+    if (schema.else !== undefined && typeof schema.else !== 'boolean' && schema.else !== undefined && schema.else.properties !== undefined) {
+      const elsePropnames = Object.keys(schema.else.properties)
+      for (const k of elsePropnames) {
+        const p = schema.else.properties[k]
+        if (typeof p === 'object' && p.default === parameters[k]) {
+          /* eslint-disable @typescript-eslint/no-dynamic-delete */
+          delete parameters[k]
+          /* eslint-enable @typescript-eslint/no-dynamic-delete */
+        }
+      }
+    }
+  }
+
+  return parameters
 }
diff --git a/packages/form/src/CollapsibleField.tsx b/packages/form/src/CollapsibleField.tsx
index c8fdf45..f4cf7b9 100644
--- a/packages/form/src/CollapsibleField.tsx
+++ b/packages/form/src/CollapsibleField.tsx
@@ -97,7 +97,7 @@ export const CollapsibleField = (props: FieldProps): JSX.Element => {
           {title}
         </h5>
         {/* error icon */}
-        {hasError ? <ErrorIcon /> : null}
+        {hasError ? <div title={JSON.stringify(props.errorSchema)}><ErrorIcon /></div> : null}
       </div>
       {/* show content when not collapsed */}
       {/* TitleField inside the ObjectField is not rendered when there is no title or name */}
diff --git a/packages/haddock3_catalog/generate_haddock3_catalog.py b/packages/haddock3_catalog/generate_haddock3_catalog.py
index 02cedcf..a4991b9 100755
--- a/packages/haddock3_catalog/generate_haddock3_catalog.py
+++ b/packages/haddock3_catalog/generate_haddock3_catalog.py
@@ -109,6 +109,7 @@ def config2schema(config):
 
     required = []
     collapsed_config = collapse_expandable(config)
+    ifthenelses = {}
     for k, v in collapsed_config.items():
         prop = {}
         prop_ui = {}
@@ -124,6 +125,23 @@ def config2schema(config):
             prop['description'] = v['short']
         if 'long' in v and v['long'] != 'No long description yet':
             prop['$comment'] = v['long']
+        if 'incompatible' in v:
+            ifthenelse = {
+                "if": {
+                    "properties": {}
+                },
+                "then": {},
+                "else": {
+                    "properties": {
+                        k: prop
+                    }
+                }
+            }
+            for ik, iv in v['incompatible'].items():
+                ifthenelse['if']['properties'][ik] = {
+                    "const": iv
+                }
+            ifthenelses[k] = ifthenelse
         if 'type' not in v:
             # if not type field treat value as dict of dicts
             # TODO instead of removing group and explevel from mol1.prot_segid dict do proper filtering and support group recursivly
@@ -336,7 +354,8 @@ def config2schema(config):
                 raise ValueError(f"Don't know how to determine type of items of {v}")
         else:
             raise ValueError(f"Don't know what to do with {k}:{v}")
-        properties[k] = prop
+        if k not in ifthenelses:
+            properties[k] = prop
         if 'group' in v and v['group'] != '' and v['group'] is not None:
             prop_ui['ui:group'] = v['group']
         if prop_ui:
@@ -349,6 +368,10 @@ def config2schema(config):
         "required": required,
         "additionalProperties": False
     }
+    if ifthenelses:
+        if len(ifthenelses) > 1:
+            raise ValueError(f"Only one ifthenelse is supported, but got {len(ifthenelses)}")
+        schema.update(list(ifthenelses.values())[0])
     return {
         "schema": schema,
         "uiSchema": uiSchema,
diff --git a/packages/haddock3_catalog/public/catalog/haddock3.easy.yaml b/packages/haddock3_catalog/public/catalog/haddock3.easy.yaml
index 92f0e37..fd9c5e5 100644
--- a/packages/haddock3_catalog/public/catalog/haddock3.easy.yaml
+++ b/packages/haddock3_catalog/public/catalog/haddock3.easy.yaml
@@ -163,17 +163,24 @@ global:
           this parameter to `true` will add the javascript library in generated files,
           therefore completely isolating haddock3 from any web call.
         type: boolean
-      less_io:
-        default: false
-        title: Reduce the amount of I/O operations.
-        description: Reduce the amount of I/O operations.
-        $comment: This option will reduce the amount of I/O operations by writing
-          less files to disk. This can be useful for example when running on a network
-          file system where I/O operations are slow.
-        type: boolean
     required:
     - run_dir
     additionalProperties: false
+    if:
+      properties:
+        mode:
+          const: batch
+    then: {}
+    else:
+      properties:
+        less_io:
+          default: false
+          title: Reduce the amount of I/O operations.
+          description: Reduce the amount of I/O operations.
+          $comment: This option will reduce the amount of I/O operations by writing
+            less files to disk. This can be useful for example when running on a network
+            file system where I/O operations are slow.
+          type: boolean
   uiSchema:
     molecules:
       items:
diff --git a/packages/haddock3_catalog/public/catalog/haddock3.expert.yaml b/packages/haddock3_catalog/public/catalog/haddock3.expert.yaml
index 3d4af04..dc28ad7 100644
--- a/packages/haddock3_catalog/public/catalog/haddock3.expert.yaml
+++ b/packages/haddock3_catalog/public/catalog/haddock3.expert.yaml
@@ -173,17 +173,24 @@ global:
           this parameter to `true` will add the javascript library in generated files,
           therefore completely isolating haddock3 from any web call.
         type: boolean
-      less_io:
-        default: false
-        title: Reduce the amount of I/O operations.
-        description: Reduce the amount of I/O operations.
-        $comment: This option will reduce the amount of I/O operations by writing
-          less files to disk. This can be useful for example when running on a network
-          file system where I/O operations are slow.
-        type: boolean
     required:
     - run_dir
     additionalProperties: false
+    if:
+      properties:
+        mode:
+          const: batch
+    then: {}
+    else:
+      properties:
+        less_io:
+          default: false
+          title: Reduce the amount of I/O operations.
+          description: Reduce the amount of I/O operations.
+          $comment: This option will reduce the amount of I/O operations by writing
+            less files to disk. This can be useful for example when running on a network
+            file system where I/O operations are slow.
+          type: boolean
   uiSchema:
     molecules:
       items:
diff --git a/packages/haddock3_catalog/public/catalog/haddock3.guru.yaml b/packages/haddock3_catalog/public/catalog/haddock3.guru.yaml
index 7676cf1..8d94561 100644
--- a/packages/haddock3_catalog/public/catalog/haddock3.guru.yaml
+++ b/packages/haddock3_catalog/public/catalog/haddock3.guru.yaml
@@ -183,17 +183,24 @@ global:
           this parameter to `true` will add the javascript library in generated files,
           therefore completely isolating haddock3 from any web call.
         type: boolean
-      less_io:
-        default: false
-        title: Reduce the amount of I/O operations.
-        description: Reduce the amount of I/O operations.
-        $comment: This option will reduce the amount of I/O operations by writing
-          less files to disk. This can be useful for example when running on a network
-          file system where I/O operations are slow.
-        type: boolean
     required:
     - run_dir
     additionalProperties: false
+    if:
+      properties:
+        mode:
+          const: batch
+    then: {}
+    else:
+      properties:
+        less_io:
+          default: false
+          title: Reduce the amount of I/O operations.
+          description: Reduce the amount of I/O operations.
+          $comment: This option will reduce the amount of I/O operations by writing
+            less files to disk. This can be useful for example when running on a network
+            file system where I/O operations are slow.
+          type: boolean
   uiSchema:
     molecules:
       items: