Implementations

LIVR is a specification, so you need an implementation for your language. All of them use the same rules format and return the same error codes. The latest version of the specification is 2.0; the previous one was 0.4.

JavaScript

LIVR 2.0Test suite: 70/70

npm: livrv2.12.1
Docs: js.livr-spec.org
Maintainer: @koorchik
Last activity: Oct 2026 ★ 185

Reference implementation. Sync and async validators, TypeScript type inference.

Perl

LIVR 2.0Test suite: 70/70

CPAN: Validator::LIVRv2.1
Maintainer: @koorchik
Last activity: Oct 2026 ★ 12

PHP

LIVR 2.0Test suite: 68/68

Packagist: validator/livr
Maintainer: @WebbyLab
Last activity: Oct 2026 ★ 47

Java

LIVR 2.0Test suite: 70/70

Maven Central: io.github.vlbaluk:validator-livrv2.0.2
Maintainer: @vlbaluk
Last activity: Oct 2026 ★ 14

Returns the standard error codes, but wraps each one together with the invalid value: {"code": "REQUIRED", "fieldValue": …}.

Ruby

LIVR 2.0Test suite: 70/70

RubyGems: ruby-livrv2.1.0
Maintainer: @fuksito
Last activity: Oct 2026 ★ 4

Erlang · Olifer

LIVR 2.0Test suite: 70/70

Maintainer: @Prots
Last activity: Oct 2026 ★ 13

Raku

LIVR 2.0Test suite: 70/70

raku.land: LIVR
Maintainer: @koorchik
Last activity: Oct 2026 ★ 6

Formerly Perl 6.

Dart

LIVR 2.0Test suite: 70/70

pub.dev: livrv0.1.0
Maintainer: @koorchik
Last activity: Oct 2026

Rust

LIVR 2.0Test suite: 70/70

crates.io: livrv0.1.0
Maintainer: @koorchik
Last activity: Oct 2026

Go

LIVR 2.0Test suite: 66/70

Go: github.com/k33nice/go-livrv2.0.0
Maintainer: @k33nice
Last activity: Mar 2020 ★ 25

Lua

LIVR 2.0Test suite: 64/68

LuaRocks: lua-livr
Maintainer: @fperrad
Last activity: Jan 2026

Swift

LIVR 2.0Test suite: 63/70 (v1.0.5)

CocoaPods: Livrv1.0.4
Maintainer: @olxbr
Last activity: Jul 2026 ★ 8

Python

LIVR 2.0Test suite: 56/70

PyPI: LIVRv2.0.1
Maintainer: @asholok
Last activity: Dec 2017 ★ 26

Erlang · Liver

LIVR 2.0Test suite: 61/70

Hex: liverv1.1.0
Maintainer: @erlangbureau
Last activity: Oct 2026 ★ 38

Package versions and repository activity are refreshed every time the site is built.

Test suite results

Every implementation is checked against the shared test suite. Every week, and whenever the specification changes, CI installs each implementation the way a user would and runs all test cases against it.

Implementation	Tested version	Passed	Details
JavaScript	`2.12.1`	70 / 70	All cases pass
Perl	`2.1`	70 / 70	All cases pass
PHP	`dev-master@93e31c9`	68 / 68	All cases pass 2 cases not counted `negative/22-not_empty_list` PHP decodes {} and [] to the same array, so an empty object can't be told apart from an empty list. php-validator-livr's own copy of the test suite adjusts this case. `negative/27-any_object` PHP decodes {} and [] to the same array, so an empty object can't be told apart from an empty list. php-validator-livr's own copy of the test suite adjusts this case.
Java	`2.0.2`	70 / 70	Errors are returned as {"code": …, "fieldValue": …} objects instead of plain error codes (the library adds the invalid value to every error), so only the codes are compared. All cases pass
Ruby	`2.1.0`	70 / 70	All cases pass
Erlang · Olifer	`2.0.2@aef75c5`	70 / 70	Not published on hex; built from the repository. All cases pass
Raku	`2.2.1`	70 / 70	Run on Rakudo Star 2024.02: LIVR 2.1.0 no longer compiles on current Rakudo (a rx:P5 regex in LIVR::Rules::Special). All cases pass
Dart	`0.1.0`	70 / 70	All cases pass
Rust	`0.1.0`	70 / 70	All cases pass
Go	`v2.0.0+incompatible`	66 / 70	4 failing cases `positive/16-email` expected no errors, got {"email10":"WRONG_EMAIL","email11":"WRONG_EMAIL","email12":"WRONG_EMAIL","email13":"WRONG_EMAIL","email20":"WRONG_EMAIL","email21":"WRONG_EMAIL","email22":"WRONG_EMAIL","email23":"WRONG_EMAIL","email25":"WRONG_EMAIL","email26":"WRONG_EMAIL","email4":"WRONG… `negative/21-list_of_different_objects` exception: interface conversion: interface {} is []interface {}, not string `negative/28-variable_object` exception: interface conversion: interface {} is map[string]interface {}, not string `negative/29-or` expected errors {"id1-1":"NOT_POSITIVE_INTEGER","id2-1":"NOT_POSITIVE_INTEGER","id3-1":"WRONG_EMAIL","id4-1":"CANNOT_BE_EMPTY","id4-2":"REQUIRED","products":[{"name":"REQUIRED","product_type":"NOT_ALLOWED_VALUE"},{"name":"REQUIRED"}]}, got {"id1-1":"NOT_POSITIVE_INTEGER","id2-1":…
Lua	`0.5.1`	64 / 68	Installed with the optional lrexlib-pcre2 and luautf8 rocks, which the `like` rule and Unicode-aware to_lc/to_uc need. 4 failing cases `positive/16-email` expected no errors, got {"email10":"WRONG_EMAIL","email25":"WRONG_EMAIL","email22":"WRONG_EMAIL","email23":"WRONG_EMAIL","email26":"WRONG_EMAIL","email7":"WRONG_EMAIL","email20":"WRONG_EMAIL","email8":"WRONG_EMAIL","email21":"WRONG_EMAIL","email12":"WRONG_EMAIL","email13":"WRONG_… `negative/16-email` expected errors {"email5":"WRONG_EMAIL","email18":"WRONG_EMAIL","value_is_empty_array":"FORMAT_ERROR","value_is_empty_hash":"FORMAT_ERROR","email23":"WRONG_EMAIL","email3":"WRONG_EMAIL","email26":"WRONG_EMAIL","value_is_array":"FORMAT_ERROR","email15":"WRONG_EMAIL","email9":"WRON… `negative/21-list_of_different_objects` expected errors {"order_id":"NOT_POSITIVE_INTEGER","only_wrong_items":["FORMAT_ERROR","FORMAT_ERROR","FORMAT_ERROR","FORMAT_ERROR","FORMAT_ERROR"],"null_item":["FORMAT_ERROR"],"selector_is_builtin_property":["FORMAT_ERROR","FORMAT_ERROR","FORMAT_ERROR","FORMAT_ERROR"],"selector_i… `negative/29-or` expected errors {"id2-1":"NOT_POSITIVE_INTEGER","id1-1":"NOT_POSITIVE_INTEGER","products":[{"product_type":"NOT_ALLOWED_VALUE","name":"REQUIRED"},{"name":"REQUIRED"}],"id4-1":"CANNOT_BE_EMPTY","id3-1":"WRONG_EMAIL","id4-2":"REQUIRED"}, got {"id2-1":"NOT_POSITIVE_INTEGER","id1-1":… 2 cases not counted `negative/22-not_empty_list` Lua decodes {} and [] to the same empty table, so an empty object can't be told apart from an empty list. lua-LIVR's own copy of the test suite adjusts this case. `negative/27-any_object` Lua decodes {} and [] to the same empty table, so an empty object can't be told apart from an empty list. lua-LIVR's own copy of the test suite adjusts this case.
Swift	`1.0.5@a362353`	63 / 70	Apple platforms only: it relies on NSPredicate format strings, which Foundation on Linux doesn't provide. Built from source in Swift 4.2 language mode on macOS. 7 failing cases `positive/16-email` expected no errors, got {"email7":"WRONG_EMAIL","email8":"WRONG_EMAIL","email10":"WRONG_EMAIL","email12":"WRONG_EMAIL","email13":"WRONG_EMAIL","email20":"WRONG_EMAIL","email21":"WRONG_EMAIL","email22":"WRONG_EMAIL","email23":"WRONG_EMAIL","email25":"WRONG_EMAIL","email26":"WRONG_… `positive/18-nested_object` expected output {"address":{"building":10,"country":"Ukraine","street":"10","zip":12345},"builtin_names":{"constructor":"Constructor value","toString":"ToString value"},"should_be_empty":{},"should_not_be_errored":""}, got {"address":{"building":10,"country":"Ukraine","street":"1… `positive/30-trim` expected output {"decimal_value":"1.2","list_of_string_values":["value1",{"key":"123"},"value2"],"object":{"string_value":"some value"},"string_value":"value","unicode_string":"Привет"}, got {"decimal_value":1.2,"list_of_string_values":["value1",{"key":"123"},"value2"],"object":{… `negative/16-email` expected errors {"email1":"WRONG_EMAIL","email2":"WRONG_EMAIL","email3":"WRONG_EMAIL","email4":"WRONG_EMAIL","email5":"WRONG_EMAIL","email6":"WRONG_EMAIL","email7":"WRONG_EMAIL","email8":"WRONG_EMAIL","email9":"WRONG_EMAIL","email10":"WRONG_EMAIL","email11":"WRONG_EMAIL","email12… `negative/21-list_of_different_objects` expected errors {"null_item":["FORMAT_ERROR"],"only_wrong_items":["FORMAT_ERROR","FORMAT_ERROR","FORMAT_ERROR","FORMAT_ERROR","FORMAT_ERROR"],"order_id":"NOT_POSITIVE_INTEGER","products":[{"material_id":"NOT_POSITIVE_INTEGER","quantity":"REQUIRED"},{"warehouse_id":"NOT_POSITIVE_I… `negative/24-iso_date` expected errors {"iso_date1":"WRONG_DATE","iso_date2":"WRONG_DATE","iso_date3":"WRONG_DATE","iso_date4":"WRONG_DATE","iso_date5":"WRONG_DATE","iso_date6":"WRONG_DATE","iso_date7":"WRONG_DATE","iso_date8":"WRONG_DATE","iso_date9":"WRONG_DATE","like_iso_date":"WRONG_DATE","value_is… `negative/29-or` expected errors {"id1-1":"NOT_POSITIVE_INTEGER","id2-1":"NOT_POSITIVE_INTEGER","id3-1":"WRONG_EMAIL","id4-1":"CANNOT_BE_EMPTY","id4-2":"REQUIRED","products":[{"name":"REQUIRED","product_type":"NOT_ALLOWED_VALUE"},{"name":"REQUIRED"}]}, got {"id1-1":"NOT_POSITIVE_INTEGER","id2-1":…
Erlang · Liver	`1.1.0`	61 / 70	Validated with liver's `rule_set => livr_spec` mode. liver has no API for registering data-defined rule aliases, so the alias cases fail. 9 failing cases `positive/17-equal_to_field` expected no errors, got {"number_as_string":"FIELDS_NOT_EQUAL"} `negative/16-email` expected errors {"email1":"WRONG_EMAIL","email10":"WRONG_EMAIL","email11":"WRONG_EMAIL","email12":"WRONG_EMAIL","email13":"WRONG_EMAIL","email14":"WRONG_EMAIL","email15":"WRONG_EMAIL","email16":"WRONG_EMAIL","email17":"WRONG_EMAIL","email18":"WRONG_EMAIL","email19":"WRONG_EMAIL",… `negative/29-or` expected errors {"id1-1":"NOT_POSITIVE_INTEGER","id2-1":"NOT_POSITIVE_INTEGER","id3-1":"WRONG_EMAIL","id4-1":"CANNOT_BE_EMPTY","id4-2":"REQUIRED","products":[{"name":"REQUIRED","product_type":"NOT_ALLOWED_VALUE"},{"name":"REQUIRED"}]}, got {"id1-1":"NOT_POSITIVE_INTEGER","id2-1":… `aliases_positive/01-adult_age` liver has no API for registering aliased rules `aliases_positive/02-address` liver has no API for registering aliased rules `aliases_positive/03-adult_age_in_user` liver has no API for registering aliased rules `aliases_negative/01-adult_age` liver has no API for registering aliased rules `aliases_negative/02-address` liver has no API for registering aliased rules `aliases_negative/03-adult_age_in_user` liver has no API for registering aliased rules
Python	`2.0.1`	56 / 70	14 failing cases `positive/17-equal_to_field` expected no errors, got {"number_as_string": "FIELDS_NOT_EQUAL"} `positive/18-nested_object` expected output {"address": {"building": 10, "country": "Ukraine", "street": "10", "zip": 12345}, "builtin_names": {"constructor": "Constructor value", "toString": "ToString value"}, "should_be_empty": {}, "should_not_be_errored": ""}, got {"address": {"building": 10, "country": … `positive/33-remove` expected output {"list_of_string_values": ["value1", {"key": "123"}, "value"], "object": {"string_value": "Vluelue Vlue"}, "string_value": "aluevaluealue"}, got {"list_of_string_values": ["value1", {"key": "123"}, "value"], "object": {"string_value": "V- V"}, "string_value": "alu… `positive/34-leave_only` expected output {"list_of_string_values": ["", {"key": "123"}, "23"], "object": {"string_value": "a-vaa"}, "string_value": "Vl l Vl"}, got {"list_of_string_values": ["", {"key": "123"}, "23"], "object": {"string_value": "aluevaluealue"}, "string_value": "Vl l Vl"} `negative/12-positive_decimal` expected errors {"number1": "NOT_POSITIVE_DECIMAL", "number2": "NOT_POSITIVE_DECIMAL", "number3": "NOT_POSITIVE_DECIMAL", "number4": "NOT_POSITIVE_DECIMAL", "value_is_array": "FORMAT_ERROR", "value_is_empty_array": "FORMAT_ERROR", "value_is_empty_hash": "FORMAT_ERROR", "value_is_… `negative/16-email` expected errors {"email1": "WRONG_EMAIL", "email10": "WRONG_EMAIL", "email11": "WRONG_EMAIL", "email12": "WRONG_EMAIL", "email13": "WRONG_EMAIL", "email14": "WRONG_EMAIL", "email15": "WRONG_EMAIL", "email16": "WRONG_EMAIL", "email17": "WRONG_EMAIL", "email18": "WRONG_EMAIL", "ema… `negative/17-equal_to_field` exception: KeyError: 'missing_field' `negative/19-list_of` expected errors {"product_ids1": ["NOT_POSITIVE_INTEGER", "REQUIRED", null, "TOO_HIGH"], "product_ids2": ["NOT_POSITIVE_INTEGER", "REQUIRED", null, "TOO_HIGH"], "product_ids3": ["NOT_POSITIVE_INTEGER", null, null, null], "user_ids": "FORMAT_ERROR"}, got {"product_ids1": ["NOT_POS… `negative/21-list_of_different_objects` exception: TypeError: argument of type 'int' is not iterable `negative/23-url` expected errors {"url1": "WRONG_URL", "url2": "WRONG_URL", "url3": "WRONG_URL", "url4": "WRONG_URL", "url5": "WRONG_URL", "value_is_array": "FORMAT_ERROR", "value_is_empty_array": "FORMAT_ERROR", "value_is_empty_hash": "FORMAT_ERROR", "value_is_hash": "FORMAT_ERROR"}, got {"url1"… `negative/24-iso_date` expected errors {"iso_date1": "WRONG_DATE", "iso_date2": "WRONG_DATE", "iso_date3": "WRONG_DATE", "iso_date4": "WRONG_DATE", "iso_date5": "WRONG_DATE", "iso_date6": "WRONG_DATE", "iso_date7": "WRONG_DATE", "iso_date8": "WRONG_DATE", "iso_date9": "WRONG_DATE", "like_iso_date": "WR… `negative/28-variable_object` exception: KeyError: 'product_type' `negative/29-or` expected errors {"id1-1": "NOT_POSITIVE_INTEGER", "id2-1": "NOT_POSITIVE_INTEGER", "id3-1": "WRONG_EMAIL", "id4-1": "CANNOT_BE_EMPTY", "id4-2": "REQUIRED", "products": [{"name": "REQUIRED", "product_type": "NOT_ALLOWED_VALUE"}, {"name": "REQUIRED"}]}, got {"id1-1": "NOT_POSITIVE_… `aliases_positive/01-adult_age` expected output {"age1": 32, "age1_custom_error": 37, "age2": 33, "age2_custom_error": 38, "age3": 35, "age3_custom_error": 100, "age4": 36, "age4_custom_error": 110, "empty_age": ""}, got {"age1": 32, "age1_custom_error": 37, "age2": 33, "age2_custom_error": 38, "age3": 35, "age…

Results of running the LIVR test suite (70 cases) against the latest version of each implementation: the published package, or the default branch when it is not published. Checked on October 29, 2026. The runners live in the conformance/ directory. Some failures come from newer test cases that were added after an implementation's last release. Cases that an implementation can't pass because of its language (for example, PHP and Lua decode {} and [] to the same value) are not counted, so its score is out of the remaining cases.

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Add it to docs/data/implementations.json and, if you can, add a test suite runner to conformance/.
Run npm run readme to update the list in the repository README and open a pull request.

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