Here are people who have contributed to development of JSON Schema generator
module of Jackson JSON processor 
(version numbers in brackets indicate release in which the problem was fixed)

Ignacio del Valle Alles (idelvall@github):

#24: Improved Schema generation for Maps
 (2.3.0)

Anton O (mavarazy@github)

#35: Add annotation based support for HyperSchema to JsonSchema
 (2.4.1)

Greg Adams (gadams00@github)

#47: VisitorContext results in incomplete json schema output
 (2.4.4)

Izek Greenfield (igreenfield@github)

#53: Add support to oneOf
 (2.6.0)

StormeHawke@github:

#57: Enum types should generate a schema that includes the possible enum values
 (2.6.0)

Sebastien Briquet (sebfz1@github)

#67: Unable to deserialize (extended/custom) Schema
 (2.6.0)

David Semke (dsemke@github)

#69: Add support for @Pattern annotations in String schemas
 (2.6.0)

Ignacio del Valle Alles (idelvall@github)

#27: Object schema properties should adhere to `@JsonPropertyOrder` and
  `@XmlType(propOrder)`
 (2.6.2)

George W Fraser (georgewfraser@github)

#80: Support NumberFormat#multipleOf
 (2.7.0)

Jakub Neubauer (jakubneubauer@github)

#77: Schema with enum array - when deserialized, the enum values are lost
 (2.7.0)

alexpeelman@github

#104: HyperSchema does not generate links for nested objects
 (2.7.5)

Sean Staley (seanstaley@github)

#119: `dependencies` property should not be an Array but Object
 (2.9.0)