AI Index / Open-source team communication tools / History

Open-source team communication tools — AI Recommendation History

What AI assistants recommended for open-source team communication tools, date by date. Every ranking we publish is frozen the day it publishes, so this is a record of what was said — not a re-computation of what today's data would say about the past.

Record: 26 dated snapshots · Aug 14, 2026 – Sep 8, 2026

Answer archive Methodology Data studies JSON

What changed

Computed by comparing each dated snapshot with the one before it. Share moves smaller than 1pp are treated as noise and left out — the same threshold that suppresses trend arrows on the ranking.

Sep 8, 2026vs Sep 7, 2026

No change above the noise floor.

Sep 7, 2026vs Sep 6, 2026

No change above the noise floor.

Sep 6, 2026vs Sep 5, 2026

Methodology change: extraction rules 5-7 → 7 between these dates. Differences below may reflect the rule change rather than a change in what AI recommends — see the methodology changelog.

▲ INPostgreSQL entered the top 10 (#11 → #10)
▼ OUTLDAP left the top 10 (#9 → #11)
▼LDAP moved #9 → #11
▲Nextcloud moved #10 → #9
▲PostgreSQL moved #11 → #10
▼LDAP -4.7pp (20.6% → 15.9%)
▼Slack -3.2pp (66.7% → 63.5%)
▼Conversations -3.2pp (34.9% → 31.7%)
▼Rocket.Chat -3.1pp (71.4% → 68.3%)
▼Matrix -1.6pp (65.1% → 63.5%)
▼Element -1.6pp (65.1% → 63.5%)

Sep 5, 2026vs Sep 4, 2026

Methodology change: extraction rules 4-7 → 5-7 between these dates. Differences below may reflect the rule change rather than a change in what AI recommends — see the methodology changelog.

▲ INLDAP entered the top 10 (#11 → #9)
▲ INNextcloud entered the top 10 (#12 → #10)
▼ OUTPostgreSQL left the top 10 (#9 → #11)
▼ OUTDiscord left the top 10 (#10 → #12)
▲LDAP moved #11 → #9
▲Nextcloud moved #12 → #10
▼PostgreSQL moved #9 → #11
▼Discord moved #10 → #12
▲Nextcloud +8.4pp (12.2% → 20.6%)
▲LDAP +6.3pp (14.3% → 20.6%)
▼Discord -4.5pp (20.4% → 15.9%)
▲Element +3.9pp (61.2% → 65.1%)
▲Slack +3.4pp (63.3% → 66.7%)
▲Zulip +3.2pp (57.1% → 60.3%)
▲Docker +2.1pp (26.5% → 28.6%)
▲Matrix +1.8pp (63.3% → 65.1%)
▲Mattermost +1.4pp (79.6% → 81%)
▼PostgreSQL -1.4pp (20.4% → 19%)

Sep 4, 2026vs Sep 3, 2026

▲ INDiscord entered the top 10 (#11 → #10)
▼ OUTNextcloud left the top 10 (#10 → #12)
▼Nextcloud moved #10 → #12
▲Discord moved #11 → #10
▼Nextcloud -6.8pp (19% → 12.2%)
▼Conversations -3.4pp (38.1% → 34.7%)
▼Rocket.Chat -3.2pp (74.6% → 71.4%)
▲Discord +2.9pp (17.5% → 20.4%)
▼Docker -2.1pp (28.6% → 26.5%)
▼Zulip -1.6pp (58.7% → 57.1%)
▼Mattermost -1.4pp (81% → 79.6%)

Sep 3, 2026vs Sep 2, 2026

No change above the noise floor.

Sep 2, 2026vs Sep 1, 2026

No change above the noise floor.

Sep 1, 2026vs Aug 31, 2026

No change above the noise floor.

Aug 31, 2026vs Aug 30, 2026

No change above the noise floor.

Aug 30, 2026vs Aug 29, 2026

No change above the noise floor.

Aug 29, 2026vs Aug 28, 2026

No change above the noise floor.

Aug 28, 2026vs Aug 27, 2026

No change above the noise floor.

Aug 27, 2026vs Aug 26, 2026

▲Slack moved #4 → #3
▼Matrix moved #3 → #4
▲PostgreSQL moved #10 → #9
▼Nextcloud moved #9 → #10
▼Nextcloud -3.1pp (22.1% → 19%)
▼Matrix -2.7pp (66.2% → 63.5%)
▼Zulip -2.3pp (61% → 58.7%)
▼Element -1.7pp (63.6% → 61.9%)
▼Docker -1.3pp (29.9% → 28.6%)
▲PostgreSQL +1.1pp (19.5% → 20.6%)

Aug 26, 2026vs Aug 25, 2026

No change above the noise floor.

Aug 25, 2026vs Aug 24, 2026

No change above the noise floor.

Aug 24, 2026vs Aug 23, 2026

No change above the noise floor.

Aug 23, 2026vs Aug 22, 2026

▲Matrix moved #5 → #3
▼Slack moved #3 → #4
▼Element moved #4 → #5
▲Matrix +5pp (61.2% → 66.2%)
▲Zulip +2.8pp (58.2% → 61%)
▲Slack +2.4pp (61.2% → 63.6%)
▲Element +2.4pp (61.2% → 63.6%)
▲Docker +2.3pp (27.6% → 29.9%)
▲Nextcloud +1.7pp (20.4% → 22.1%)
▲Conversations +1.2pp (37.8% → 39%)
▲PostgreSQL +1.1pp (18.4% → 19.5%)

Aug 22, 2026vs Aug 21, 2026

No change above the noise floor.

Aug 21, 2026vs Aug 20, 2026

No change above the noise floor.

Aug 20, 2026vs Aug 19, 2026

No change above the noise floor.

Aug 19, 2026vs Aug 18, 2026

No change above the noise floor.

Aug 18, 2026vs Aug 17, 2026

▲ INPostgreSQL entered the top 10 (#11 → #10)
▼ OUTLDAP left the top 10 (#10 → #11)
▲Slack moved #5 → #3
▼Matrix moved #3 → #5
▲PostgreSQL moved #11 → #10
▼LDAP moved #10 → #11
▼Conversations -4.2pp (42% → 37.8%)
▼Rocket.Chat -3.1pp (78.6% → 75.5%)
▼Matrix -2.2pp (63.4% → 61.2%)
▼Element -1.3pp (62.5% → 61.2%)
▼Nextcloud -1pp (21.4% → 20.4%)

Aug 17, 2026vs Aug 16, 2026

No change above the noise floor.

Aug 16, 2026vs Aug 15, 2026

▼Slack moved #3 → #5
▲Matrix moved #4 → #3
▲Element moved #5 → #4
▼Mattermost -2.7pp (84.8% → 82.1%)
▼Rocket.Chat -2.4pp (81% → 78.6%)
▼Slack -2.2pp (63.8% → 61.6%)
▼Conversations -1.8pp (43.8% → 42%)
▼Docker -1.8pp (28.6% → 26.8%)
▼Nextcloud -1.5pp (22.9% → 21.4%)
▼Zulip -1.1pp (60% → 58.9%)
▼LDAP -1.1pp (19% → 17.9%)

Aug 15, 2026vs Aug 14, 2026

Methodology change: extraction rules 4-5 → 4-7 between these dates. Differences below may reflect the rule change rather than a change in what AI recommends — see the methodology changelog.

▲Slack moved #5 → #3
▼Matrix moved #3 → #4
▼Element moved #4 → #5
▼Nextcloud -3.1pp (26% → 22.9%)
▲Slack +2.8pp (61% → 63.8%)
▲Docker +2.6pp (26% → 28.6%)
▼LDAP -1.8pp (20.8% → 19%)
▲Mattermost +1.7pp (83.1% → 84.8%)
▼Conversations -1.7pp (45.5% → 43.8%)
▼Matrix -1.1pp (64.9% → 63.8%)
▼Zulip -1pp (61% → 60%)

The ranking, date by date

Top 10 on each archived date, exactly as published. Cite a date and it stays true: snapshots are append-only, and a correction appends a new revision rather than overwriting the original.

Sep 8, 202663 sampled answers · window 2026-08-11 – 2026-09-08 · rules v7

#1Mattermost81%
#2Rocket.Chat68.3%
#3Slack63.5%
#4Matrix63.5%
#5Element63.5%
#6Zulip60.3%
#7Conversations31.7%
#8Docker28.6%
#9Nextcloud20.6%
#10PostgreSQL19%

Sep 7, 202663 sampled answers · window 2026-08-10 – 2026-09-07 · rules v7

#1Mattermost81%
#2Rocket.Chat68.3%
#3Slack63.5%
#4Matrix63.5%
#5Element63.5%
#6Zulip60.3%
#7Conversations31.7%
#8Docker28.6%
#9Nextcloud20.6%
#10PostgreSQL19%

Sep 6, 202663 sampled answers · window 2026-08-09 – 2026-09-06 · rules v7

#1Mattermost81%
#2Rocket.Chat68.3%
#3Slack63.5%
#4Matrix63.5%
#5Element63.5%
#6Zulip60.3%
#7Conversations31.7%
#8Docker28.6%
#9Nextcloud20.6%
#10PostgreSQL19%

Sep 5, 202663 sampled answers · window 2026-08-08 – 2026-09-05 · rules v5-7

#1Mattermost81%
#2Rocket.Chat71.4%
#3Slack66.7%
#4Matrix65.1%
#5Element65.1%
#6Zulip60.3%
#7Conversations34.9%
#8Docker28.6%
#9LDAP20.6%
#10Nextcloud20.6%

Sep 4, 202649 sampled answers · window 2026-08-07 – 2026-09-04 · rules v4-7

#1Mattermost79.6%
#2Rocket.Chat71.4%
#3Slack63.3%
#4Matrix63.3%
#5Element61.2%
#6Zulip57.1%
#7Conversations34.7%
#8Docker26.5%
#9PostgreSQL20.4%
#10Discord20.4%

Sep 3, 202663 sampled answers · window 2026-08-06 – 2026-09-03 · rules v4-7

#1Mattermost81%
#2Rocket.Chat74.6%
#3Slack63.5%
#4Matrix63.5%
#5Element61.9%
#6Zulip58.7%
#7Conversations38.1%
#8Docker28.6%
#9PostgreSQL20.6%
#10Nextcloud19%

Sep 2, 202663 sampled answers · window 2026-08-05 – 2026-09-02 · rules v4-7

#1Mattermost81%
#2Rocket.Chat74.6%
#3Slack63.5%
#4Matrix63.5%
#5Element61.9%
#6Zulip58.7%
#7Conversations38.1%
#8Docker28.6%
#9PostgreSQL20.6%
#10Nextcloud19%

Sep 1, 202663 sampled answers · window 2026-08-04 – 2026-09-01 · rules v4-7

#1Mattermost81%
#2Rocket.Chat74.6%
#3Slack63.5%
#4Matrix63.5%
#5Element61.9%
#6Zulip58.7%
#7Conversations38.1%
#8Docker28.6%
#9PostgreSQL20.6%
#10Nextcloud19%

Aug 31, 202663 sampled answers · window 2026-08-03 – 2026-08-31 · rules v4-7

#1Mattermost81%
#2Rocket.Chat74.6%
#3Slack63.5%
#4Matrix63.5%
#5Element61.9%
#6Zulip58.7%
#7Conversations38.1%
#8Docker28.6%
#9PostgreSQL20.6%
#10Nextcloud19%

Aug 30, 202663 sampled answers · window 2026-08-02 – 2026-08-30 · rules v4-7

#1Mattermost81%
#2Rocket.Chat74.6%
#3Slack63.5%
#4Matrix63.5%
#5Element61.9%
#6Zulip58.7%
#7Conversations38.1%
#8Docker28.6%
#9PostgreSQL20.6%
#10Nextcloud19%

Aug 29, 202663 sampled answers · window 2026-08-01 – 2026-08-29 · rules v4-7

#1Mattermost81%
#2Rocket.Chat74.6%
#3Slack63.5%
#4Matrix63.5%
#5Element61.9%
#6Zulip58.7%
#7Conversations38.1%
#8Docker28.6%
#9PostgreSQL20.6%
#10Nextcloud19%

Aug 28, 202663 sampled answers · window 2026-07-31 – 2026-08-28 · rules v4-7

#1Mattermost81%
#2Rocket.Chat74.6%
#3Slack63.5%
#4Matrix63.5%
#5Element61.9%
#6Zulip58.7%
#7Conversations38.1%
#8Docker28.6%
#9PostgreSQL20.6%
#10Nextcloud19%

Aug 27, 202663 sampled answers · window 2026-07-30 – 2026-08-27 · rules v4-7

#1Mattermost81%
#2Rocket.Chat74.6%
#3Slack63.5%
#4Matrix63.5%
#5Element61.9%
#6Zulip58.7%
#7Conversations38.1%
#8Docker28.6%
#9PostgreSQL20.6%
#10Nextcloud19%

Aug 26, 202677 sampled answers · window 2026-07-29 – 2026-08-26 · rules v4-7

#1Mattermost81.8%
#2Rocket.Chat75.3%
#3Matrix66.2%
#4Slack63.6%
#5Element63.6%
#6Zulip61%
#7Conversations39%
#8Docker29.9%
#9Nextcloud22.1%
#10PostgreSQL19.5%

Aug 25, 202677 sampled answers · window 2026-07-28 – 2026-08-25 · rules v4-7

#1Mattermost81.8%
#2Rocket.Chat75.3%
#3Matrix66.2%
#4Slack63.6%
#5Element63.6%
#6Zulip61%
#7Conversations39%
#8Docker29.9%
#9Nextcloud22.1%
#10PostgreSQL19.5%

Aug 24, 202677 sampled answers · window 2026-07-27 – 2026-08-24 · rules v4-7

#1Mattermost81.8%
#2Rocket.Chat75.3%
#3Matrix66.2%
#4Slack63.6%
#5Element63.6%
#6Zulip61%
#7Conversations39%
#8Docker29.9%
#9Nextcloud22.1%
#10PostgreSQL19.5%

Aug 23, 202677 sampled answers · window 2026-07-26 – 2026-08-23 · rules v4-7

#1Mattermost81.8%
#2Rocket.Chat75.3%
#3Matrix66.2%
#4Slack63.6%
#5Element63.6%
#6Zulip61%
#7Conversations39%
#8Docker29.9%
#9Nextcloud22.1%
#10PostgreSQL19.5%

Aug 22, 202698 sampled answers · window 2026-07-25 – 2026-08-22 · rules v4-7

#1Mattermost81.6%
#2Rocket.Chat75.5%
#3Slack61.2%
#4Element61.2%
#5Matrix61.2%
#6Zulip58.2%
#7Conversations37.8%
#8Docker27.6%
#9Nextcloud20.4%
#10PostgreSQL18.4%

Aug 21, 202698 sampled answers · window 2026-07-24 – 2026-08-21 · rules v4-7

#1Mattermost81.6%
#2Rocket.Chat75.5%
#3Slack61.2%
#4Element61.2%
#5Matrix61.2%
#6Zulip58.2%
#7Conversations37.8%
#8Docker27.6%
#9Nextcloud20.4%
#10PostgreSQL18.4%

Aug 20, 202698 sampled answers · window 2026-07-23 – 2026-08-20 · rules v4-7

#1Mattermost81.6%
#2Rocket.Chat75.5%
#3Slack61.2%
#4Element61.2%
#5Matrix61.2%
#6Zulip58.2%
#7Conversations37.8%
#8Docker27.6%
#9Nextcloud20.4%
#10PostgreSQL18.4%

Aug 19, 202698 sampled answers · window 2026-07-22 – 2026-08-19 · rules v4-7

#1Mattermost81.6%
#2Rocket.Chat75.5%
#3Slack61.2%
#4Element61.2%
#5Matrix61.2%
#6Zulip58.2%
#7Conversations37.8%
#8Docker27.6%
#9Nextcloud20.4%
#10PostgreSQL18.4%

Aug 18, 202698 sampled answers · window 2026-07-21 – 2026-08-18 · rules v4-7

#1Mattermost81.6%
#2Rocket.Chat75.5%
#3Slack61.2%
#4Element61.2%
#5Matrix61.2%
#6Zulip58.2%
#7Conversations37.8%
#8Docker27.6%
#9Nextcloud20.4%
#10PostgreSQL18.4%

Aug 17, 2026112 sampled answers · window 2026-07-20 – 2026-08-17 · rules v4-7

#1Mattermost82.1%
#2Rocket.Chat78.6%
#3Matrix63.4%
#4Element62.5%
#5Slack61.6%
#6Zulip58.9%
#7Conversations42%
#8Docker26.8%
#9Nextcloud21.4%
#10LDAP17.9%

Aug 16, 2026112 sampled answers · window 2026-07-19 – 2026-08-16 · rules v4-7

#1Mattermost82.1%
#2Rocket.Chat78.6%
#3Matrix63.4%
#4Element62.5%
#5Slack61.6%
#6Zulip58.9%
#7Conversations42%
#8Docker26.8%
#9Nextcloud21.4%
#10LDAP17.9%

Aug 15, 2026105 sampled answers · window 2026-07-18 – 2026-08-15 · rules v4-7

#1Mattermost84.8%
#2Rocket.Chat81%
#3Slack63.8%
#4Matrix63.8%
#5Element62.9%
#6Zulip60%
#7Conversations43.8%
#8Docker28.6%
#9Nextcloud22.9%
#10LDAP19%

Aug 14, 202677 sampled answers · window 2026-07-17 – 2026-08-14 · rules v4-5

#1Mattermost83.1%
#2Rocket.Chat81.8%
#3Matrix64.9%
#4Element63.6%
#5Slack61%
#6Zulip61%
#7Conversations45.5%
#8Docker26%
#9Nextcloud26%
#10LDAP20.8%

Read any date directly

Every archived date is machine-readable at /api/index/open-source-team-communication/as-of/<YYYY-MM-DD>, which returns the ranking as it stood, with the extraction version and revision it was published under. Dates before the record begins return no_record rather than a recomputation — we do not reconstruct history on demand and present it as what we said. See what the engines actually said.

[ORBATOR]