# \#json **URL:** https://erlangforums.com/tag/json/317.md [Latest](https://erlangforums.com/latest.md) · [Categories](https://erlangforums.com/categories.md) · [Tags](https://erlangforums.com/tags.md) --- ## [Glazer - the Swiss Army knife of parsing JSON/YAML/CSV](https://erlangforums.com/t/glazer-the-swiss-army-knife-of-parsing-json-yaml-csv/5714)
**Author:** [@saleyn](https://erlangforums.com/u/saleyn)\ **Replies:** 13\ **Last updated:** [September 25, 2026, 10:18am UTC](https://erlangforums.com/t/glazer-the-swiss-army-knife-of-parsing-json-yaml-csv/5714 "2026-09-25T10:18:39Z")
glazer started as a blazing-fast NIF JSON codec (single-pass, straight to/from native terms - no AST). In 0.3.0, the same engine now parses and encodes YAML and CSV too. The numbers: JSON: faster encoding than everyt… --- ## [Jiffy 2.0.2](https://erlangforums.com/t/jiffy-2-0-2/5779)
**Author:** [@nickva](https://erlangforums.com/u/nickva)\ **Replies:** 4\ **Last updated:** [July 14, 2026, 6:03pm UTC](https://erlangforums.com/t/jiffy-2-0-2/5779 "2026-07-14T18:03:07Z")
Changes Reduce encoder memory allocations #301 Flush the buffer into iolist segments with a chunk size that doubles (up to 64KB). Large documents should now have O(log n) allocations. Encode maps directly without … --- ## [Glazejson - fast JSON encoder/decoder for Erlang or Elixir](https://erlangforums.com/t/glazejson-fast-json-encoder-decoder-for-erlang-or-elixir/5701)
**Author:** [@saleyn](https://erlangforums.com/u/saleyn)\ **Replies:** 8\ **Last updated:** [June 9, 2026, 3:15pm UTC](https://erlangforums.com/t/glazejson-fast-json-encoder-decoder-for-erlang-or-elixir/5701 "2026-06-09T15:15:54Z")
I released a new JSON encoding/decoding library that uses NIF C++ backend and consistently outperforms most of other implementations. Fast Erlang NIF JSON encoder/decoder with a hand-rolled recursive-descent decoder an… --- ## [Jiffy - 2.0 release](https://erlangforums.com/t/jiffy-2-0-release/5699)
**Author:** [@nickva](https://erlangforums.com/u/nickva)\ **Replies:** 0\ **Last updated:** [June 7, 2026, 5:41am UTC](https://erlangforums.com/t/jiffy-2-0-release/5699 "2026-06-07T05:41:47Z")
A new release if Jiffy is out. There are quite a few performance improvements, some new features, bug fixes, and increased test coverage. Performance I used nickva/bench Benchee-based json benchmark to test performanc… --- ## [gmconfig - JSON-Schema validator and config lookup API](https://erlangforums.com/t/gmconfig-json-schema-validator-and-config-lookup-api/5631)
**Author:** [@uwiger](https://erlangforums.com/u/uwiger)\ **Replies:** 2\ **Last updated:** [May 16, 2026, 1:25pm UTC](https://erlangforums.com/t/gmconfig-json-schema-validator-and-config-lookup-api/5631 "2026-05-16T13:25:45Z")
gmconfig is a configuration management application derived from the configuration subsystem of Aeternity and Gajumaru. It sports a pretty complete JSON-Schema validator and an efficient configuration lookup API. In this… --- ## [Spectra - Type-driven JSON encoding/decoding, validation, and OpenAPI generation](https://erlangforums.com/t/spectra-type-driven-json-encoding-decoding-validation-and-openapi-generation/5530)
**Author:** [@andreashasse](https://erlangforums.com/u/andreashasse)\ **Replies:** 0\ **Last updated:** [April 6, 2026, 2:38pm UTC](https://erlangforums.com/t/spectra-type-driven-json-encoding-decoding-validation-and-openapi-generation/5530 "2026-04-06T14:38:02Z")
I’d like to announce Spectra, a data validation and serialization library for Erlang inspired by Pydantic. The core idea: your Erlang type definitions become the single source of truth for JSON encoding, decoding, valid… --- ## [Has the STDLIB \`json\` module been backported to older Erlang versions?](https://erlangforums.com/t/has-the-stdlib-json-module-been-backported-to-older-erlang-versions/4630)
**Author:** [@weaver](https://erlangforums.com/u/weaver)\ **Replies:** 2\ **Last updated:** [April 1, 2025, 3:23pm UTC](https://erlangforums.com/t/has-the-stdlib-json-module-been-backported-to-older-erlang-versions/4630 "2025-04-01T15:23:25Z")
Hi folks! I’m trying to use ELP with OTP 25. ELP relies on rebar3’s experimental manifest command, which seems to rely on the json module added in OTP 27. Since json is written in pure Erlang, I’m curious if anyone has… --- ## [Json\_polyfill - A polyfill for the OTP json module (EEP68)](https://erlangforums.com/t/json-polyfill-a-polyfill-for-the-otp-json-module-eep68/4472)
**Author:** [@williamthome](https://erlangforums.com/u/williamthome)\ **Replies:** 0\ **Last updated:** [February 9, 2025, 5:23pm UTC](https://erlangforums.com/t/json-polyfill-a-polyfill-for-the-otp-json-module-eep68/4472 "2025-02-09T17:23:38Z")
json\_polyfill This lib is just a copy of the json module proposed in EEP 68 and introduced in OTP 27 by Michał Muskała. Its intent is to act as a polyfill for apps that cannot currently be updated to OTP 27 or higher. T… --- ## [Attempt to use jiffy results in \_nif\_init not found in jiffy.so](https://erlangforums.com/t/attempt-to-use-jiffy-results-in-nif-init-not-found-in-jiffy-so/4185)
**Author:** [@olegzil](https://erlangforums.com/u/olegzil)\ **Replies:** 2\ **Last updated:** [November 15, 2024, 6:25pm UTC](https://erlangforums.com/t/attempt-to-use-jiffy-results-in-nif-init-not-found-in-jiffy-so/4185 "2024-11-15T18:25:36Z")
I’ve been using jiffy without problems, but recently, after building my server I get: exception exit: {on\_load\_function\_failed,jiffy, {error, {bad\_lib, … --- ## [Json module: error when encoding text with accents](https://erlangforums.com/t/json-module-error-when-encoding-text-with-accents/4065)
**Author:** [@zabrane](https://erlangforums.com/u/zabrane)\ **Replies:** 5\ **Last updated:** [October 8, 2024, 7:38pm UTC](https://erlangforums.com/t/json-module-error-when-encoding-text-with-accents/4065 "2024-10-08T19:38:55Z")
Hi guys I’ve got a list of binaries to encode in JSON. As you can see, the second binary in the list is in french: Erlang/OTP 27 \[erts-15.1\] \[source\] \[64-bit\] \[smp:8:8\] \[ds:8:8:8\] \[async-threads:1\] 1\> L = \[ \<\<"100872… --- ## [Best library for JSON file parsing. Which one?](https://erlangforums.com/t/best-library-for-json-file-parsing-which-one/4026)
**Author:** [@alexandr](https://erlangforums.com/u/alexandr)\ **Replies:** 4\ **Last updated:** [September 26, 2024, 6:01am UTC](https://erlangforums.com/t/best-library-for-json-file-parsing-which-one/4026 "2024-09-26T06:01:56Z")
Hello all! What is the best library for JSON files parsing? Found few of them: GitHub - talentdeficit/jsx: an erlang application for consuming, producing and manipulating json. inspired by yajl GitHub - gearnode/erl-… --- ## [Buult-in JSON decoding keys as existing atoms](https://erlangforums.com/t/buult-in-json-decoding-keys-as-existing-atoms/3863)
**Author:** [@eproxus](https://erlangforums.com/u/eproxus)\ **Replies:** 7\ **Last updated:** [August 28, 2024, 10:17am UTC](https://erlangforums.com/t/buult-in-json-decoding-keys-as-existing-atoms/3863 "2024-08-28T10:17:15Z")
A common feature that almost all existing JSON libraries support is converting the resulting keys to atoms. While the new json module technically supports this, the interface is quite cumbersome: Push = fun(Key, Value, … --- ## [Euneus - A JSON parser and generator in pure Erlang](https://erlangforums.com/t/euneus-a-json-parser-and-generator-in-pure-erlang/3031)
**Author:** [@williamthome](https://erlangforums.com/u/williamthome)\ **Replies:** 18\ **Last updated:** [August 6, 2024, 9:47pm UTC](https://erlangforums.com/t/euneus-a-json-parser-and-generator-in-pure-erlang/3031 "2024-08-06T21:47:41Z")
Euneus What is Euneus? A JSON parser and generator in pure Erlang. Euneus is a rewrite of Thoas. Like Thoas, both the parser and generator fully conform to RFC 8259 and ECMA 404. Why Euneus over Thoas? Thoas is incred… --- ## [ASN.1 to JSON Schema](https://erlangforums.com/t/asn-1-to-json-schema/3525)
**Author:** [@vances](https://erlangforums.com/u/vances)\ **Replies:** 1\ **Last updated:** [August 2, 2024, 8:47am UTC](https://erlangforums.com/t/asn-1-to-json-schema/3525 "2024-08-02T08:47:19Z")
Are there any tools hidden in the asn1 application which would help me generate JSON Schema to describe the JER encoded output of a asn1ct generated encoder? The problem may not be Erlang specific however I cannot find … --- ## [JSONPull - A JSON pull parser for Erlang](https://erlangforums.com/t/jsonpull-a-json-pull-parser-for-erlang/3306)
**Author:** [@nixx](https://erlangforums.com/u/nixx)\ **Replies:** 0\ **Last updated:** [February 16, 2024, 2:58pm UTC](https://erlangforums.com/t/jsonpull-a-json-pull-parser-for-erlang/3306 "2024-02-16T14:58:16Z")
Hex.pm package - Source code I would like to start this post by referring you to the talk A Fast, Compliant JSON Pull Parser for Writing Robust Applications by Jonathan Müller at CppCon 2023. Watching that talk is what… --- ## [The need for "protocols" in Erlang](https://erlangforums.com/t/the-need-for-protocols-in-erlang/2973)
**Author:** [@josevalim](https://erlangforums.com/u/josevalim)\ **Replies:** 54\ **Last updated:** [November 5, 2023, 5:16pm UTC](https://erlangforums.com/t/the-need-for-protocols-in-erlang/2973 "2023-11-05T17:16:38Z")
At Code BEAM Europe, I had several discussions which all pointed out towards a need for protocols, or a similar solution, in Erlang. This post is an attempt to summarize them and start a discussion on the topic. What ar… --- ## [Ensuring jsone encodes/decodes to correct representations](https://erlangforums.com/t/ensuring-jsone-encodes-decodes-to-correct-representations/2696)
**Author:** [@scherrey](https://erlangforums.com/u/scherrey)\ **Replies:** 6\ **Last updated:** [June 18, 2023, 2:41pm UTC](https://erlangforums.com/t/ensuring-jsone-encodes-decodes-to-correct-representations/2696 "2023-06-18T14:41:04Z")
We’re dealing with a lot of ingress/egress of data encoded as JSON. While JSON is normally quite lovely, it’s insistence that all numbers are floats is absolutely inane especially when we deal with numeric values that ar… --- ## [Thoas - Elixir's Jason JSON library converted to Erlang](https://erlangforums.com/t/thoas-elixirs-jason-json-library-converted-to-erlang/879)
**Author:** [@lpil](https://erlangforums.com/u/lpil)\ **Replies:** 41\ **Last updated:** [March 24, 2023, 6:40pm UTC](https://erlangforums.com/t/thoas-elixirs-jason-json-library-converted-to-erlang/879 "2023-03-24T18:40:41Z")
Hello everyone! I’ve converted @michalmuskala’s wonderful Elixir Jason library to Erlang. It has a smaller feature-set compared to Jason, see the README for details there. Why convert Jason to Erlang? I wanted to us… --- ## [Using records for json objects](https://erlangforums.com/t/using-records-for-json-objects/1053)
**Author:** [@mdbergmann](https://erlangforums.com/u/mdbergmann)\ **Replies:** 5\ **Last updated:** [February 9, 2022, 7:27am UTC](https://erlangforums.com/t/using-records-for-json-objects/1053 "2022-02-09T07:27:32Z")
Hi. I’d like to use records as json object, because the handling of records is quite nice with the available macros for records. For json I use the library ljson (GitHub - lfex/ljson: An LFE library which provides a un…