Here are people who have contributed to the development of Jackson JSON processor
databind core component, version 2.x
(version numbers in brackets indicate release in which the problem was fixed)

(note: for older credits, check out release notes for 1.x versions)

Tatu Saloranta, tatu.saloranta@iki.fi: author

Pascal Glinas:
  * Contributed fixes to 'MappingIterator' handling (Pull#58 and Pull#59)
   (2.1.0)
  * Reported #220: ContainerNode missing 'createNumber(BigInteger)'
   (2.2.2)

Joern Huxhorn: (huxi@github)
  * Suggested [JACKSON-636]: Add 'SerializationFeature.ORDER_MAP_ENTRIES_BY_KEYS' to allow
    forced sorting of Maps during serialization
   (2.0.0)
  * Reported #479: NPE on trying to deserialize a `String[]` that contains null
   (2.4.1)

James Roper:
 * Requested [JACKSON-732]: Allow 'AnnotationIntrospector.findContentDeserializer()'
    (and similar) to return instance, not just Class<?> for instance
  (2.0.0)
 * Suggested [JACKSON-800]: Adding a method for letting modules register
    DeserializationProblemHandlers
  (2.0.0)

Casey Lucas:
 * Reported [JACKSON-798]: Problem with external type id, creators
  (2.0.0)

Tammo van Lessen:
 * Reported [JACKSON-811]: Problems with @JsonIdentityInfo, abstract types
  (2.0.0)
 * Reported [JACKSON-814]: Parsing RFC822/RFC1123 dates failes on non-US locales
  (2.0.0)

Raymond Myers:
 * Suggested [JACKSON-810]: Deserialization Feature: Allow unknown Enum values via
    'DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_AS_NULL'
  (2.0.0)

Ryan Gardner:
 * Contributed #5 -- Add support for maps with java.util.Locale keys
    to the set of StdKeyDeserializers
  (2.0.1)

Razvan Dragut:
 * Suggested [JACKSON-850]: Allow use of zero-arg factory methods as "default creator"
  (2.1.0)

Duncan Atkinson:
 * Reported [JACKSON-851]: State corruption with ObjectWriter, DefaultPrettyPrinter
  (2.1.0)

Mark Wolfe:
 * Suggested #45: Add `@JsonNaming()` for per-class naming strategy overrides
  (2.1.0)

Dmitry Katsubo:
 * Contributed patch for #65: Add getters to `ObjectMapper`, DeserializationContext,
   DeserializationFactory.
  (2.1.0)

Francis Galiegue:
 * Reported #93 (and suggested fix): bug in `ObjectMapper.setAll(...)'
  implementation
  (2.1.1)
 * Reported #433: `ObjectMapper`'s `.valueToTree()` wraps `JsonSerializable` objects
  into a POJONode
  (2.3.3)
 * Contributed #434: Ensure that DecimalNodes with mathematically equal values are equal
  (2.4.0)

kelaneren@github:
 * Reported #157, contributed unit test: NPE when registering same module twice.
  (2.1.4)

Eric Tschetter (cheddar@github):
  * Reported issues #166, #167, #170 (regressions from 1.9.x to 2.x)
   (2.1.4)

Thierry D (thierryd@github)
  * Reported #214: Problem with LICENSE, NOTICE, Android packaging
   (2.2.2)

Luke G-H (lukegh@github)
  * Reported #223: Duplicated nulls with @JsonFormat(shape=Shape.ARRAY)
   (2.2.2)

Karl Moore (karldmoore@github)
  * Reported #217: JsonProcessingExceptions not all wrapped as expected
   (2.2.2)

David Phillips:
  * Requested #308: Improve serialization and deserialization speed of `java.util.UUID`
   (2.3.0)

Seth Pellegrino (jivesoft):
  * Contributed #317: Fix `JsonNode` support for nulls bound to	`ObjectNode`, `ArrayNode`
   (2.3.0)

Florian Schoppmann (fschopp@github)
  * Reported #358: `IterableSerializer` ignoring	annotated content serializer
   (2.3.1)
  * Reported #359: Converted object not using explicitly annotated serializer
   (2.4.0)

Martin Traverso:
  * Reported #406: Cannot use external type id + @JsonTypeIdResolver
   (2.3.2)

Matthew Morrissette:
  * Contributed #381: Allow inlining/unwrapping of value from single-component JSON array
   (2.4.0)

Will Palmeri: (wpalmeri@github)
  * Contributed #407: Make array and Collection serializers use configured value null handler
   (2.4.0)

Cemalettin Koc: (cemo@github)
  * Reported #353: Problems with polymorphic types, `JsonNode` (related to #88)
   (2.4.0)

Ben Fagin: (UnquietCode@github)
  * Suggested #442: Make `@JsonUnwrapped` indicate property inclusion
   (2.4.0)
  * Contributed #81/#455: Allow use of @JsonUnwrapped with typed (@JsonTypeInfo) classes,
    provided that (new) feature `SerializationFeature.FAIL_ON_UNWRAPPED_TYPE_IDENTIFIERS`
    is disabled
   (2.4.0)

Chris Cleveland:
  * Suggested #463: Add 'JsonNode.asText(String defaultValue)`
   (2.4.0)

Benson Margulies:
  * Reported #467: Unwanted POJO's embedded in tree via serialization to tree
   (2.4.0)

Steve Sanbeg: (sanbeg@github)
  * Contributed #482: Make date parsing error behavior consistent with JDK
   (2.4.1)
