api.md

Public API

Bob provides read-only JSON endpoints for searching build artifacts and Docker tags. The API is available at https://bob.hex.pm and doesn't require authentication.

Both endpoints return at most 100 results at a time. Pass a positive integer as the offset query parameter to fetch the next page. Missing, zero, negative, and invalid offsets are treated as 0.

Every response includes:

Field	Description
total	Number of records matching the filters.
offset	Offset used for the current page.
page_size	Maximum number of records returned per page. This is always 100.

Results are ordered by build time, newest first, unless an endpoint documents another sort option.

Build artifacts

GET /api/artifacts searches OTP build artifacts.

Query parameters

Parameter	Matching behavior
query	Case-insensitive substring match against name and ref.
kind	Exact match against the artifact kind.
arch	Exact match against the CPU architecture.
os	Exact match against the operating system name and version.
offset	Number of matching records to skip. Defaults to 0.

When multiple filters are present, a result must match all of them.

curl --get \
  --header 'accept: application/json' \
  --data-urlencode 'kind=otp' \
  --data-urlencode 'arch=amd64' \
  --data-urlencode 'os=ubuntu-24.04' \
  https://bob.hex.pm/api/artifacts

The artifacts array contains objects with these fields:

Field	Description
kind	Artifact kind.
arch	CPU architecture.
os	Operating system name and version.
name	Build name, such as an OTP tag or branch.
ref	Git revision used for the build.
sha256	SHA-256 checksum, or null for artifacts that predate checksum storage.
built_at	Build time as an ISO 8601 UTC timestamp.

Example response, with all but the first matching artifact omitted:

{
  "artifacts": [
    {
      "arch": "amd64",
      "built_at": "2026-08-04T11:10:04.000000Z",
      "kind": "otp",
      "name": "OTP-29.0.5",
      "os": "ubuntu-24.04",
      "ref": "5cf5f9725452f4e1b6a4890e8ff0305d76924b98",
      "sha256": "1ecf8a20104afa053e6701e36ec1485cbce1a2fa4aef962d5e73f9eb5c6e9fc0"
    }
  ],
  "offset": 0,
  "page_size": 100,
  "total": 168
}

Docker tags

GET /api/docker searches tags in the Hex Docker repositories. Each filter uses a case-sensitive prefix match.

Query parameters

Parameter	Matching behavior
repo	Prefix match against the repository name. For example, hexpm/elixir also matches hexpm/elixir-amd64 and hexpm/elixir-arm64.
tag	Prefix match against the full Docker tag.
arch	Prefix match against any architecture provided by the tag.
elixir_version	Prefix match against the Elixir version parsed from the tag.
erlang_version	Prefix match against the Erlang version parsed from the tag.
os	Prefix match against the operating system parsed from the tag.
os_version	Prefix match against the operating system version parsed from the tag.
sort	Comma-separated descending sort keys in precedence order: elixir_version, erlang_version, os, os_version, or built_at. Defaults to built_at. Version keys use numeric-aware ordering. Elixir and Erlang put a stable release before prereleases of the same release. built_at is exclusive; including it ignores every other sort key. Build time and ID break remaining ties.
offset	Number of matching records to skip. Defaults to 0.

When multiple filters are present, a result must match all of them. If tag is present, the API ignores elixir_version, erlang_version, os, and os_version. The repo and arch filters still apply.

curl --get \
  --header 'accept: application/json' \
  --data-urlencode 'repo=hexpm/elixir' \
  --data-urlencode 'elixir_version=1.18' \
  --data-urlencode 'erlang_version=27' \
  --data-urlencode 'os=ubuntu' \
  https://bob.hex.pm/api/docker

The tags array contains objects with these fields:

Field	Description
repo	Docker repository name.
tag	Docker tag.
archs	Architectures provided by the tag.
built_at	Build time as an ISO 8601 UTC timestamp.

Example response, with all but the first matching tag omitted:

{
  "offset": 0,
  "page_size": 100,
  "tags": [
    {
      "archs": [
        "amd64",
        "arm64"
      ],
      "built_at": "2026-08-04T13:00:30.476813Z",
      "repo": "hexpm/elixir",
      "tag": "1.18.4-erlang-27.3.4.16-ubuntu-jammy-20260627"
    }
  ],
  "total": 3707
}