X Algorithm Changelog

Release timeline and parameter baseline for xai-org/x-algorithm — the code that ranks the X For You feed.

Tracking 183 parameters · baseline 2026-08-13 (a389166) · page built 2026-08-14

Observed changes & watcher status → · RSS

Why this exists

X publishes the algorithm as squashed snapshots. Every commit in the repository carries the same message — Open-source X Recommendation Algorithm — so the history tells you nothing about what changed. The only way to find out is to diff entire trees. The most recent release changed +19,375 / −234 lines across 300+ files.

This page keeps a readable record: what shipped in each release, and what every published parameter is currently set to. When the next release lands, the values below become the baseline it is diffed against.

Release timeline

2026-01-20 · aaa167b

First publication

The ranking pipeline only: home-mixer, the pipeline framework, Phoenix and Thunder. Structure was visible; none of the numbers were.

79 files 5 modules 0.4 MB
2026-05-15 · 0bfc279

Content classifiers added

grox arrives and home-mixer roughly triples in file count. Still no published parameter values.

216 files (+137) 6 modules 1.0 MB
New module What it does
grox Content classifiers for posts and media

New module	What it does
grox	Content classifiers for posts and media

2026-08-13 · a389166

Values and the safety stack

Twenty new modules — visibility filtering, the labelling rule engine, account scoring, enforcement — plus param.rs, which publishes the scoring weights for the first time. This release is 89% of the repository as it stands.

2,015 files (+1,799) 26 modules 13.4 MB

New module	What it does
abuse-enforcement-service	Acts on model scores: label, challenge, suspend
adult-content	Adult-media classifier training and calibration
agatha	Account labels from blocks/reports relative to favorites
bdsm	Behavioural bot detection over account action sequences
botmaker	Rule engine: language, compiler, runtime
botmaker-rules	The rules scarecrow loads
clip	Image/text embedding model training
docs	Worked example of a published parameter change
media-model-proxy	Serves image and video models
phoenix-rankall	Maintains the retrieval index
phoenix-rankall-strato	Event layer deciding which index a post belongs in
pnsfwmedia	Adult-media classifier combining CLIP + account scores
safety-label-user-agg	Labels an account for what its posts collected
scarecrow	Applies label rules to events as they happen
simclusters	Cluster-similarity candidate source
under-the-hood	Per-account label transparency report
user-cred-v2	PageRank over follow and engagement edges
visibility-filtering	Decides allow / interstitial / drop per post and viewer
visibility-filtering-client	Client and post safety-label types
vm-ranker	DPP reranking over post embeddings

expected ~Q4 2026

Next release

Releases have landed roughly quarterly. The parameter values below will be diffed against it.

No parameter history exists before 2026-08-13. The January and May releases published structure without values — param.rs, registry.rs and the enforcement rules all appear for the first time in August. That release is the origin point of any weight timeline, which is why the baseline below starts there rather than earlier.

Parameter baseline

Values as published on 2026-08-13. The file header states these are mirrored from production feature-switch defaults, so they reflect the primary production values at sync time — not necessarily what any given request sees, since parameters are overridable per experiment.

Scoring weights

Parameter	Value	Notes
BidirectionalFollowDwellWeightBoostrust_home_mixer_bidirectional_follow_dwell_weight_boost	0.0	Tested alongside the reply boost in the same A/B test but never shipped broadly. Still 0.0.
BidirectionalFollowReplyWeightBoostrust_home_mixer_bidirectional_follow_reply_weight_boost	15.0	Added to ReplyWeight when the post is an original (not a reply, not a repost) from an author the viewer mutually follows, taking it from 5.0 to 20.0. Launched at 20.0 on 2026-07-13, lowered to 15.0 on 2026-07-24 — the one change X documented in docs/BIDIRECTIONAL_BOOST_CHANGE.md.
ClickWeightrust_home_mixer_click_weight	0.4	Weight on P(viewer opens the post). Below a like.
ContDwellTimeWeightrust_home_mixer_cont_dwell_time_weight	0.004	Weight on predicted dwell seconds (a continuous head, not a probability). Small per-unit at 0.004 because it multiplies a duration rather than a 0–1 value.
DwellWeightrust_home_mixer_dwell_weight	0.0	Set to 0.0. The binary dwell head is inactive; continuous dwell time is carried by ContDwellTimeWeight instead.
FavoriteWeightrust_home_mixer_favorite_weight	0.5	Weight on P(viewer likes this post). At 0.5 it is the lowest-valued positive engagement in the model — a predicted like is worth 1/40th of a predicted copy-link share.
FollowAuthorWeightrust_home_mixer_follow_author_weight	4.0	Weight on P(viewer follows the author from this post). Eight times a like.
OpenLinkWeightrust_home_mixer_open_link_weight	0.2	Weight on P(viewer opens an external link). At 0.2 it is among the weakest positive signals — sending people off-platform earns little.
ProfileClickWeightrust_home_mixer_profile_click_weight	0.0	Set to 0.0 — profile clicks currently contribute nothing to the score.
QuoteWeightrust_home_mixer_quote_weight	5.0	Weight on P(viewer quote-posts). Equal to reply at 5.0.
ReplyWeightrust_home_mixer_reply_weight	5.0	Weight on P(viewer replies to this post) — i.e. the post attracting a reply, not the post being a reply. Ten times the weight of a like.
RetweetWeightrust_home_mixer_retweet_weight	1.0	Weight on P(viewer reposts). Twice a like, but a twentieth of a copy-link share.
ShareViaCopyLinkWeightrust_home_mixer_share_via_copy_link_weight	20.0	The largest positive weight in the model at 20.0 — forty times a like. Copying a link is the strongest single signal the ranker recognises.
ShareViaDmWeightrust_home_mixer_share_via_dm_weight	5.0	Weight on P(viewer sends the post via DM). Ten times a like — private sharing is read as a much stronger signal than public approval.
ShareWeightrust_home_mixer_share_weight	2.0	Weight on P(viewer taps share). Four times a like.

Negative weights

Parameter	Value	Notes
BlockAuthorWeightrust_home_mixer_block_author_weight	-31.2	Weight on P(viewer blocks the author). 62x a like.
MuteAuthorWeightrust_home_mixer_mute_author_weight	-58.8	Weight on P(viewer mutes the author). 118x a like — muting is penalised harder than blocking.
NotDwelledWeightrust_home_mixer_not_dwelled_weight	-0.02	Small penalty for a post the viewer scrolls past without dwelling.
NotInterestedWeightrust_home_mixer_not_interested_weight	-43.2	Weight on P(viewer taps 'not interested'). Negative, and 86x the magnitude of a like.
ReportWeightrust_home_mixer_report_weight	-234.0	The largest weight in the model in either direction: 468x a like. The code comment notes weights blend how much an action is valued with how rare it is, and reports are very rare.

Post-scoring multipliers

Parameter	Value	Notes
AuthorDiversityDecayrust_home_mixer_author_diversity_decay	0.5	Base of the author-diversity decay. Multiplier = (1 - floor) * decay^k + floor, where k counts how many of that author's posts already rank above this one in the same candidate pool. At 0.5 the second post from an author keeps 62.5% of its score and the eighth is already at the floor.
AuthorDiversityFloorrust_home_mixer_author_diversity_floor	0.25	Lower bound of the diversity multiplier. No matter how many posts an author has in one slate, none falls below 25% of its pre-diversity score.
EnableOonRescoreForInNetworkRepliesRetweetsrust_home_mixer_enable_oon_rescore_for_in_network_replies_retweets	true	When true, replies and reposts are discounted by OonWeightFactor even for viewers who follow the author. This is why replies lose reach with your own followers.
OonWeightFactorrust_home_mixer_oon_weight_factor	0.75	Multiplier applied to posts from accounts the viewer does not follow. Also applied to replies and reposts from accounts the viewer DOES follow when EnableOonRescoreForInNetworkRepliesRetweets is on.
TopicOonWeightFactorrust_home_mixer_topic_oon_weight_factor	0.5	Replaces OonWeightFactor when the request carries topic IDs — a steeper discount for out-of-network posts in topic-scoped requests.

New-author cold start

Parameter	Value	Notes
ColdStartFollowerCaprust_home_mixer_cold_start_follower_cap	1000	Upper bound on author follower count for cold-start eligibility. Above this the boost never applies — the mechanism is aimed at small accounts.
ColdStartImpressionThresholdrust_home_mixer_cold_start_impression_threshold	1000	A post qualifies only while its view count is below this number.
ColdStartMaxPostAgeSecsrust_home_mixer_cold_start_max_post_age_secs	86400	Freshness limit for cold-start eligibility in the treatment arm — 24 hours.
ColdStartSlotMaxrust_home_mixer_cold_start_slot_max	16	Upper bound (exclusive) of that slot range. With min 15 and max 16 the target is effectively the 16th-ranked score.
ColdStartSlotMinrust_home_mixer_cold_start_slot_min	15	Lower bound of the slot whose score the boosted post is lifted to. One eligible post per request is raised to a randomly chosen slot in [min, max).
LowImpressionsMaxPositionRatiorust_home_mixer_low_impressions_max_boost_position_ratio	0.85	A post must already rank within this fraction of the scored pool to be cold-start eligible. Posts in the bottom 15% are not rescued.

Diversity reranking

Parameter	Value	Notes
VMRankerDppMaxSelectedRankrust_home_mixer_vm_ranker_dpp_max_selected_rank	150	How many posts the greedy DPP selection returns before stopping.
VMRankerDppThetarust_home_mixer_vm_ranker_dpp_theta	0.65	Trade-off knob for the determinantal point process in vm-ranker. Enters the kernel as alpha = theta / (2 * (1 - theta)); higher theta weights score over dissimilarity.

Candidate sourcing

Parameter	Value	Notes
PhoenixMaxResultsrust_home_mixer_phoenix_max_results	1000	Maximum candidates returned by Phoenix retrieval (out-of-network).
PhoenixScoresResultSizerust_home_mixer_phoenix_scores_result_size	2800	Number of candidates carried into scoring.
ThunderMaxResultsrust_home_mixer_thunder_max_results	1200	Maximum candidates returned by Thunder (in-network, posts from accounts the viewer follows).

Model inputs

Parameter	Value	Notes
EnableInferredGenderHydrationrust_home_mixer_enable_inferred_gender_hydration	true	Hydrates an inferred gender attribute for the viewer into the model input.
EnableIpFeaturerust_home_mixer_enable_geo_features	true	Feature-switch key is rust_home_mixer_enable_geo_features. When on, IP-derived location is hydrated into the request. The Phoenix config carries a 10,000,000-entry IP embedding table.
EnableUserInstalledAppsHydrationrust_home_mixer_enable_user_installed_apps_hydration	true	Hydrates the viewer's installed-app list into the model input.
MaxSeqLengthRetrievalrust_home_mixer_max_seq_length_retrieval	1024	Same limit for the retrieval model.
MaxSeqLengthScoringrust_home_mixer_max_seq_length_scoring	1024	Maximum length of the viewer's action-history sequence fed to the ranking model.

Scoring mode

Parameter	Value	Notes
ValueModelModerust_home_mixer_value_model_mode	"weighted"	Selects the scoring formula. 'weighted' is the linear weighted sum described above; 'dwell_regret_sigmoid' and 'gated_dwell_regret' switch to an alternative objective with its own weight set (negatives from -8,000 to -60,000).

Holdouts

Parameter	Value	Notes
EnableInventoryHoldoutrust_home_mixer_enable_inventory_holdout	false	When on, a configured percentage of posts is withheld deterministically per post and viewer. Currently off with all percentages at 0.

All published parameters

All 183 parameters in param.rs. The 43 above are repeated here; the remaining 140 are mostly experiment routing, cluster IDs and infrastructure flags.

Parameter	Type	Value
AdsBlenderTyperust_home_mixer_ads_blender	String	"partition_organic_low_risk"
AdsTimeGapClampHirust_home_mixer_ads_time_gap_clamp_hi	f64	2.0
AdsTimeGapClampLorust_home_mixer_ads_time_gap_clamp_lo	f64	0.5
AdsTimeGapMinOrganicGaprust_home_mixer_ads_time_gap_min_organic_gap	u32	3
AdsTimeGapTSecrust_home_mixer_ads_time_gap_t_sec	f64	4.0
AuthorDiversityDecayrust_home_mixer_author_diversity_decay	f64	0.5
AuthorDiversityFloorrust_home_mixer_author_diversity_floor	f64	0.25
AuthorIsControlrust_home_mixer_author_is_control	bool	false
AuthorIsTreatmentrust_home_mixer_author_is_treatment	bool	false
AuthorPhoenixMoeEnabledrust_home_mixer_author_phoenix_moe_enabled	bool	false
AuthorServedMetricsAuthorIdsrust_home_mixer_author_served_metrics_author_ids	Vec<u64>	[]
BidirectionalFollowDwellWeightBoostrust_home_mixer_bidirectional_follow_dwell_weight_boost	f64	0.0
BidirectionalFollowReplyWeightBoostrust_home_mixer_bidirectional_follow_reply_weight_boost	f64	15.0
BlockAuthorWeightrust_home_mixer_block_author_weight	f64	-31.2
ClickDwellLowFavRatePenaltyAlpharust_home_mixer_click_dwell_low_fav_rate_penalty_alpha	f64	0.5
ClickDwellLowFavRatePenaltyBaselinerust_home_mixer_click_dwell_low_fav_rate_penalty_baseline	f64	0.01
ClickDwellLowFavRatePenaltyCaprust_home_mixer_click_dwell_low_fav_rate_penalty_cap	f64	1.0
ClickDwellLowFavRatePenaltyFloorrust_home_mixer_click_dwell_low_fav_rate_penalty_floor	f64	0.01
ClickWeightrust_home_mixer_click_weight	f64	0.4
ColdStartFollowerCaprust_home_mixer_cold_start_follower_cap	i64	1000
ColdStartImpressionThresholdrust_home_mixer_cold_start_impression_threshold	u32	1000
ColdStartMaxPostAgeSecsrust_home_mixer_cold_start_max_post_age_secs	u64	86400
ColdStartSlotMaxrust_home_mixer_cold_start_slot_max	u32	16
ColdStartSlotMinrust_home_mixer_cold_start_slot_min	u32	15
ContActiveSecs5mResidualNormWeightrust_home_mixer_cont_active_secs_5m_residual_norm_weight	f64	0.0
ContClickDwellTimeWeightrust_home_mixer_cont_click_dwell_time_weight	f64	0.0
ContDwellTimeWeightrust_home_mixer_cont_dwell_time_weight	f64	0.004
DwellRegretAlphaFavoriterust_home_mixer_dwell_regret_alpha_favorite	f64	1.0
DwellRegretAlphaQuoterust_home_mixer_dwell_regret_alpha_quote	f64	1.0
DwellRegretAlphaReplyrust_home_mixer_dwell_regret_alpha_reply	f64	1.0
DwellRegretAlphaRetweetrust_home_mixer_dwell_regret_alpha_retweet	f64	1.0
DwellRegretAlphaSharerust_home_mixer_dwell_regret_alpha_share	f64	1.0
DwellRegretAlphaShareViaCopyLinkrust_home_mixer_dwell_regret_alpha_share_via_copy_link	f64	1.0
DwellRegretAlphaShareViaDmrust_home_mixer_dwell_regret_alpha_share_via_dm	f64	1.0
DwellRegretDwellFloorrust_home_mixer_dwell_regret_dwell_floor	f64	1.0
DwellRegretGateBiasrust_home_mixer_dwell_regret_gate_bias	f64	1.033918
DwellRegretGateHysteresisBandrust_home_mixer_dwell_regret_gate_hysteresis_band	f64	0.0
DwellRegretGateThresholdrust_home_mixer_dwell_regret_gate_threshold	f64	-0.634264
DwellRegretGateWeightsrust_home_mixer_dwell_regret_gate_weights	String	"seq_len:0.530298,n_fav:-0.082139,n_reply:0.485541,n_rt_quote:0.056561,n_vqv:-0.072778,n_click:-0.176675,n_bm_share:-0.167574,n_profile_follow:-0.221285,n_photo:-0.106004,n_negfb:0.031839,n_7d:-0.075799,n_1d:-0.241730,active_days:0.047017,active_days_7d:-0.126896,days_since_last:-0.034238,span_days:-0.052186,followers:-0.066642,followings:0.064140,account_age_years:-0.045455"
DwellRegretNegBlockAuthorrust_home_mixer_dwell_regret_neg_block_author	f64	-8000.0
DwellRegretNegMuteAuthorrust_home_mixer_dwell_regret_neg_mute_author	f64	-15000.0
DwellRegretNegNotInterestedrust_home_mixer_dwell_regret_neg_not_interested	f64	-10000.0
DwellRegretNegReportrust_home_mixer_dwell_regret_neg_report	f64	-60000.0
DwellRegretTemperaturerust_home_mixer_dwell_regret_temperature	f64	10.0
DwellWeightrust_home_mixer_dwell_weight	f64	0.0
EnableAdAdjacentServedFilterrust_home_mixer_enable_ad_adjacent_served_filter	bool	false
EnableAdsInjectionLoggingrust_home_mixer_enable_ads_injection_logging	bool	true
EnableAdsSourcerust_home_mixer_enable_ads_source	bool	true
EnableAllAuthorFollowHydrationrust_home_mixer_enable_all_author_follow_hydration	bool	true
EnableAuthorDiversityrust_home_mixer_enable_author_diversity	bool	true
EnableAuthorServedMetricsExperimentBucketrust_home_mixer_enable_author_served_metrics_experiment_bucket	bool	false
EnableBidirectionalFollowHydrationrust_home_mixer_enable_bidirectional_follow_hydration	bool	true
EnableCachedPostsrust_home_mixer_enable_cached_posts	bool	true
EnableClickDwellLowFavRatePenaltyrust_home_mixer_enable_click_dwell_low_fav_rate_penalty	bool	false
EnableContextFeaturesrust_home_mixer_enable_context_features	bool	true
EnableEngagementCountsHydrationrust_home_mixer_enable_engagement_counts_hydration	bool	true
EnableEntryIdRandomHashrust_home_mixer_enable_entry_id_random_hash	bool	false
EnableExplicitEngagementSignalsrust_home_mixer_enable_explicit_engagement_signals	bool	true
EnableFeedSurveyrust_home_mixer_enable_feed_survey	bool	false
EnableFollowingRepliedUsersFacepilerust_home_mixer_enable_following_replied_users_facepile	bool	false
EnableImplicitEngagementSignalsrust_home_mixer_enable_implicit_engagement_signals	bool	true
EnableInferredGenderHydrationrust_home_mixer_enable_inferred_gender_hydration	bool	true
EnableInventoryHoldoutrust_home_mixer_enable_inventory_holdout	bool	false
EnableIpFeaturerust_home_mixer_enable_geo_features	bool	true
EnableJetfuelFrameMlbCarouselrust_home_mixer_jetfuel_frame_mlb_carousel_enabled	bool	false
EnableJetfuelFrameNflrust_home_mixer_jetfuel_frame_nfl_enabled	bool	false
EnableJetfuelFrameNflTimelinePinnedrust_home_mixer_jetfuel_frame_nfl_timeline_pinned_enabled	bool	false
EnableJetfuelFrameNflTimelineRotationrust_home_mixer_jetfuel_frame_nfl_timeline_rotation_enabled	bool	false
EnableJetfuelFrameSoccerrust_home_mixer_jetfuel_frame_soccer_enabled	bool	false
EnableJetfuelFramesrust_home_mixer_enable_jetfuel_frames	bool	false
EnableMpnScoringrust_home_mixer_enable_mpn_scoring	bool	false
EnableMultiplicativePostUnexploredrust_home_mixer_enable_multiplicative_post_unexplored	bool	false
EnableMutualFollowJaccardHydrationrust_home_mixer_enable_mutual_follow_jaccard_hydration	bool	false
EnableNewUserMinEngagementFilterrust_home_mixer_enable_new_user_min_engagement_filter	bool	false
EnableOonRescoreForInNetworkRepliesRetweetsrust_home_mixer_enable_oon_rescore_for_in_network_replies_retweets	bool	true
EnablePhoenixMOESourcerust_home_mixer_enable_phoenix_moe_source	bool	false
EnablePhoenixRequestCacheSideEffectrust_home_mixer_enable_phoenix_request_cache_side_effect	bool	true
EnablePhoenixRetrievalFallbackrust_home_mixer_phoenix_retrieval_enable_fallback	bool	false
EnablePhoenixRetrievalStatsExperimentBucketrust_home_mixer_enable_phoenix_retrieval_stats_experiment_bucket	bool	false
EnablePhoenixSourcerust_home_mixer_enable_phoenix_source	bool	true
EnablePromptsrust_home_mixer_enable_prompts	bool	true
EnablePublishSeenIdsToKafkarust_home_mixer_enable_publish_seen_ids_kafka	bool	true
EnableQuotedVqvDurationCheckrust_home_mixer_enable_quoted_vqv_duration_check	bool	false
EnableRankingrust_home_mixer_enable_ranking	bool	true
EnableRetrievalSequenceHydrationrust_home_mixer_enable_retrieval_sequence_hydration	bool	true
EnableScoringSequenceHydrationrust_home_mixer_enable_scoring_sequence_hydration	bool	true
EnableSemanticIdHydrationrust_home_mixer_enable_semantic_id_hydration	bool	true
EnableServedFilterAllRequestsrust_home_mixer_enable_served_filter_all_requests	bool	true
EnableSimclustersSourcerust_home_mixer_enable_simclusters_source	bool	true
EnableTopicFeedbackContextrust_home_mixer_enable_topic_feedback_context	bool	false
EnableTweetMixerSourcerust_home_mixer_enable_tweet_mixer_source	bool	false
EnableUrtMigrationComponentsrust_home_mixer_enable_urt_migration_components	bool	true
EnableUserInstalledAppsHydrationrust_home_mixer_enable_user_installed_apps_hydration	bool	true
EnableUserInstalledAppsV2rust_home_mixer_enable_user_installed_apps_v2	bool	false
EnableVMRankerrust_home_mixer_enable_vm_ranker	bool	true
EnableViewerColdStartrust_home_mixer_enable_viewer_cold_start_boost	bool	true
EnableWhoToFollowModulerust_home_mixer_enable_who_to_follow_module	bool	true
EnableXaiVfClientrust_home_mixer_enable_xai_vf_client	bool	true
EngagementSignalsMaxPerTyperust_home_mixer_engagement_signals_max_per_type	usize	15
ExcludeServedTweetIdsDurationrust_home_mixer_exclude_served_tweet_ids_duration_minutes	u32	10
ExcludeServedTweetIdsNumberrust_home_mixer_exclude_served_tweet_ids_number	usize	100
FavoriteWeightrust_home_mixer_favorite_weight	f64	0.5
FeedSurveyFatigueHoursrust_home_mixer_feed_survey_fatigue_hours	u32	24
FollowAuthorWeightrust_home_mixer_follow_author_weight	f64	4.0
FollowingRepliedUsersFacepileMaxPostsrust_home_mixer_following_replied_users_facepile_max_posts	i64	0
FollowingRepliedUsersFacepileMinUsersrust_home_mixer_following_replied_users_facepile_min_users	i64	0
InventoryHoldoutOriginalsPercentrust_home_mixer_inventory_holdout_originals_percent	u32	0
InventoryHoldoutRepliesPercentrust_home_mixer_inventory_holdout_replies_percent	u32	0
InventoryHoldoutRetweetsPercentrust_home_mixer_inventory_holdout_retweets_percent	u32	0
LogSlateContextrust_home_mixer_log_slate_context	bool	false
LowImpressionsMaxPositionRatiorust_home_mixer_low_impressions_max_boost_position_ratio	f64	0.85
MaxPostsToCacherust_home_mixer_max_posts_to_cache	usize	750
MaxSeqLengthRetrievalrust_home_mixer_max_seq_length_retrieval	u32	1024
MaxSeqLengthScoringrust_home_mixer_max_seq_length_scoring	u32	1024
MinVideoDurationMsrust_home_mixer_min_video_duration_ms	i32	10_000
MultiplicativePostUnexploredAlpharust_home_mixer_multiplicative_post_unexplored_alpha	f64	0.0
MuteAuthorWeightrust_home_mixer_mute_author_weight	f64	-58.8
NewUserAgeThresholdSecsrust_home_mixer_new_user_age_threshold_secs	u64	0
NewUserMinEngagementFilterMaxAccountAgeSecsrust_home_mixer_new_user_min_engagement_filter_max_account_age_secs	u64	1800
NewUserMinEngagementFilterMaxResurrectionAgeSecsrust_home_mixer_new_user_min_engagement_filter_max_resurrection_age_secs	u64	1800
NewUserMinEngagementFilterMetricrust_home_mixer_new_user_min_engagement_filter_metric	String	"fav"
NewUserMinEngagementFilterUseRatiorust_home_mixer_new_user_min_engagement_filter_use_ratio	bool	false
NewUserMinEngagementThresholdrust_home_mixer_new_user_min_engagement_threshold	f64	0.0
NotDwelledWeightrust_home_mixer_not_dwelled_weight	f64	-0.02
NotInterestedWeightrust_home_mixer_not_interested_weight	f64	-43.2
OonWeightFactorrust_home_mixer_oon_weight_factor	f64	0.75
OpenLinkWeightrust_home_mixer_open_link_weight	f64	0.2
PhoenixAggregationTyperust_home_mixer_phoenix_aggregation_type	String	"DENSE_WITH_SHORT_DWELL"
PhoenixInferenceClusterIdrust_home_mixer_phoenix_inference_cluster_id	String	"Experiment1Fou"
PhoenixMOEMaxResultsrust_home_mixer_phoenix_moe_max_results	u32	200
PhoenixMaxResultsrust_home_mixer_phoenix_max_results	u32	1000
PhoenixMoeCodivertViewerIsControlrust_home_mixer_phoenix_moe_codivert_viewer_is_control	bool	false
PhoenixMoeCodivertViewerIsTreatmentrust_home_mixer_phoenix_moe_codivert_viewer_is_treatment	bool	false
PhoenixRankerNewUserHistoryThresholdrust_home_mixer_phoenix_ranker_new_user_history_threshold	u64	0
PhoenixRankerNewUserInferenceClusterIdrust_home_mixer_phoenix_ranker_new_user_inference_cluster_id	String	"Experiment1Fou"
PhoenixRequestCacheSideEffectTtlSecondsrust_home_mixer_phoenix_request_cache_side_effect_ttl_seconds	u64	10800
PhoenixRetrievalAggregationTyperust_home_mixer_phoenix_retrieval_aggregation_type	String	"DENSE_WITH_SHORT_DWELL"
PhoenixRetrievalInferenceClusterIdrust_home_mixer_phoenix_retrieval_inference_cluster_id	String	"Experiment1Fou"
PhoenixRetrievalMOEInferenceClusterIdrust_home_mixer_phoenix_retrieval_moe_inference_cluster_id	String	"Experiment1Fou"
PhoenixRetrievalNewUserHistoryThresholdrust_home_mixer_phoenix_retrieval_new_user_history_threshold	u64	0
PhoenixRetrievalNewUserInferenceClusterIdrust_home_mixer_phoenix_retrieval_new_user_inference_cluster_id	String	"Experiment1Lap7"
PhoenixRetrievalTopicInferenceClusterIdrust_home_mixer_phoenix_retrieval_topic_inference_cluster_id	String	"Experiment2Fou"
PhoenixScoresResultSizerust_home_mixer_phoenix_scores_result_size	u32	2800
PhoenixXdsRetrievalMaxRetriesrust_home_mixer_phoenix_xds_retrieval_max_retries	u32	0
PhotoExpandWeightrust_home_mixer_photo_expand_weight	f64	0.05
PostUnexploredWeightrust_home_mixer_post_unexplored_weight	f64	0.02
PostUnexploredWeightInNetworkOnlyrust_home_mixer_post_unexplored_weight_in_network_only	bool	true
ProfileClickWeightrust_home_mixer_profile_click_weight	f64	0.0
QuoteWeightrust_home_mixer_quote_weight	f64	5.0
QuotedClickWeightrust_home_mixer_quoted_click_weight	f64	0.05
QuotedVqvWeightrust_home_mixer_quoted_vqv_weight	f64	0.0
ReplyWeightrust_home_mixer_reply_weight	f64	5.0
ReportWeightrust_home_mixer_report_weight	f64	-234.0
RetweetWeightrust_home_mixer_retweet_weight	f64	1.0
ShadowTrafficDefaultPercentrust_home_mixer_shadow_traffic_default_percent	f64	0.3
ShadowTrafficPhoenixClusterRatesrust_home_mixer_shadow_traffic_phoenix_cluster_rates	Vec<String>	["Experiment6Fou:1.5"]
ShadowTrafficPhoenixClustersListrust_home_mixer_shadow_traffic_phoenix_clusters_list	Vec<String>	[]
ShadowTrafficPhoenixRetrievalClustersListrust_home_mixer_shadow_traffic_phoenix_retrieval_clusters_list	Vec<String>	[]
ShareViaCopyLinkWeightrust_home_mixer_share_via_copy_link_weight	f64	20.0
ShareViaDmWeightrust_home_mixer_share_via_dm_weight	f64	5.0
ShareWeightrust_home_mixer_share_weight	f64	2.0
SidServerEndpointrust_home_mixer_sid_server_endpoint	String	"xds://xai-recsys-sid-v8-root.prod.recsys-infra:grpc"
ThunderAlgorithmrust_home_mixer_thunder_algorithm	String	"default"
ThunderClusterIdrust_home_mixer_thunder_cluster_id	String	"amp"
ThunderMaxResultsrust_home_mixer_thunder_max_results	u32	1200
TopicFilteringIdrust_home_mixer_topic_filtering_experiment_id	String	"PostBased50Pct"
TopicFilteringOverridesrust_home_mixer_topic_filtering_overrides	String	""
TopicOonWeightFactorrust_home_mixer_topic_oon_weight_factor	f64	0.5
TweetMixerMaxResultsrust_home_mixer_tweet_mixer_max_results	u32	800
UasSourceDataTyperust_home_mixer_uas_source_data_type	String	"NEW_UUA_ARROW"
UseEngagementCounterViewCountForImpressionBoostrust_home_mixer_use_engagement_counter_view_count_for_impression_boost	bool	true
UseXdsForUasrust_home_mixer_use_xds_for_uas	bool	true
UserActionsClusterIdrust_home_mixer_user_actions_cluster_id	String	"Fou"
VMRankerClusterIdrust_home_mixer_vm_ranker_cluster_id	String	"Experiment3"
VMRankerDppMaxSelectedRankrust_home_mixer_vm_ranker_dpp_max_selected_rank	u32	150
VMRankerDppThetarust_home_mixer_vm_ranker_dpp_theta	f64	0.65
VMRankerEnableFallbackrust_home_mixer_vm_ranker_enable_fallback	bool	false
VMRankerSendHeadWeightsrust_home_mixer_vm_ranker_send_head_weights	bool	false
VMRankerValueModelIdrust_home_mixer_vm_ranker_value_model_id	String	"dpp"
ValueModelModerust_home_mixer_value_model_mode	String	"weighted"
VideoOpenWeightrust_home_mixer_video_open_weight	f64	0.05
VqvWeightrust_home_mixer_vqv_weight	f64	0.05
WhoToFollowFatigueHoursrust_home_mixer_who_to_follow_fatigue_hours	u32	30

Caveats

These are defaults, not guarantees. Parameters are read from a configuration system so they can be varied per experiment. A value here is the production default at sync time, not what every request uses.

Some values are deliberately withheld. The bot-detection operating points in bdsm/runtime/sink_policy.yaml are replaced with a 9.99 sentinel, the follower floor in the enforcement rules is annotated as a mock value, and the Grok classifier prompts are absent entirely. The repository says this is to reduce gaming.

Weights are not the whole score. Each weight multiplies a probability produced by a trained model. The model weights are not published, so the published numbers describe how predictions are combined — not what the predictions are.

Monetization is not in this repository. It covers ranking and visibility only. Nothing here counts qualified impressions or computes payouts.