public REST | HackerRank stats API Docs

No login. The site still serves /rest/hackers/... JSON to a logged-out Chrome UA. This API is a typed proxy, not an HTML scrape. Empty heatmaps are common. That is upstream, not Redis.

Playground: playground.

HackerRankAPI in services/client.py:

http

GET /rest/contests/master/hackers/{username}/profile
GET /rest/hackers/{username}/scores_elo
GET /rest/hackers/{username}/badges
GET /rest/hackers/{username}/contest_participation?offset=0&limit=50
GET /rest/hackers/{username}/rating_histories_elo
GET /rest/hackers/{username}/submission_histories
GET /rest/hackers/{username}/recent_challenges?limit=100&response_version=v2
GET /rest/contests/master/challenges/{slug}

recent_challenges is the full solved history despite the name. Pagination is cursor, max 25 pages. Timeout 20s.

Submission history keys are epoch seconds or ISO dates. Decoder accepts both. Heatmaps are often empty even when the UI shows activity. CodeTrace already treats an empty heatmap as “no calendar”, not an error.

Topics = challenge track.name, process _TRACK_CACHE. Active badge = max stars then level.

Mapper copies realName, userAvatar, countryName, school, company, aboutMe, websites, github/twitter/linkedin. Contests: badge.name → rank, plus topPercentage and globalRanking when present. Rating is derived from contest history. Heatmap levels are already 0 to 4 from the decoder.

End-to-end walk#

Timeout 20s. Follow redirects. Profile missing model → "user does not exist". Scores, badges, contests, ratings, submissions, recent challenges tolerate 404 (and recent challenges also 500) so a thin profile still builds a card.

sequenceDiagram
  participant B as Browser
  participant API as hackerrank-stats
  participant HR as hackerrank.com/rest

  B->>API: GET /alice/stats
  API->>HR: GET contests/master/hackers/alice/profile
  API->>HR: GET hackers/alice/badges
  API->>HR: GET hackers/alice/recent_challenges cursor pages
  API->>HR: GET contests/master/challenges/slug for tracks
  API-->>B: envelope platform hackerrank

fetch_all_recent_challenges loops up to 25 pages. Stops on last_page, missing cursor, or cursor equal to the previous one. Challenge detail fills _TRACK_CACHE for topic bars.

Submission history keys mix epoch seconds and ISO dates. parse_submission_history accepts both. Plenty of real accounts return {}. CodeTrace treats an empty heatmap as “no calendar”, not an error.