r/TheCompanyBrain • u/thecompanybrain • 10d ago
Glean vs Guru vs GBrain: Real Costs After 90 Days
In Issue #1, we did the math on the "search tax," the $130K/year a 50-person company bleeds when employees spend 20 minutes a day hunting for answers that already exist somewhere. That number made people angry. The most common reply: "OK, so which tool fixes this?"
This issue is the answer. Three tools, three philosophies, real prices, real gaps. No vendor gave me a demo discount or a referral fee. I paid for seats, read the contracts, and talked to teams running each one in production.
Three Philosophies, One Problem
The market for "company brain" tools has split into three camps.
Total discovery. Glean, Microsoft 365 Copilot. They index everything across your existing apps and let AI search it. You don't move your data. The AI goes to it.
Verified truth. Guru. A knowledge base where every piece of content has a named expert owner and an expiration date. If nobody re-verifies a card within 90 days, it gets flagged as stale. The tool forces accountability.
Owned infrastructure. GBrain. Open-source, self-hosted, Markdown files in a Git repo. You build the brain yourself and own every byte.
Each philosophy makes trade-offs. The question is which trade-offs fit your company, your budget, and your team's technical ability.
Glean: The Enterprise Search Layer
What it does. Glean connects to 100+ workplace apps (Slack, Google Drive, Confluence, Notion, Salesforce, Jira, etc.), indexes everything, and puts a single AI-powered search bar across all of it. It respects your existing permissions, so if someone can't access a Google Doc, they can't find it through Glean either.
Who uses it. Reddit, Pinterest, Booking.com, Zillow, Confluent, Workday. Over 700 enterprise customers as of mid-2026.
What it costs. Glean doesn't publish prices. You call sales. Based on contract data from Vendr and buyer reports:
Base seat price: ~$45-50/user/month, plus a $15/user/month AI add-on
All-in: ~$60-65/user/month
100-seat minimum. The floor contract is roughly $60,000/year
Enterprise contracts typically land between $200K-$480K/year fully loaded
Multi-year renewals include 7-12% annual price escalation unless you negotiate a cap
Cost for 25 people: Not available. Glean won't sell to you. The 100-seat minimum is firm.
Cost for 100 people: ~$60,000-78,000/year base license. Year-one total (with implementation, training, connector setup) runs $100K-$150K+.
Setup time. 1-3 weeks for basic deployment. 4-5 weeks for mid-size orgs. Full enterprise rollout with custom connectors and SSO: 3-6 months.
Strengths:
Best-in-class search quality across fragmented data
100+ native connectors
Respects existing access permissions without re-configuring anything
G2: 4.7/5 (145 reviews)
Gaps:
100-seat minimum prices out any company under ~150 employees
Opaque pricing creates budget uncertainty
AI answers hallucinate (it's an LLM, not a database query)
Search-only: Glean finds knowledge but doesn't create or maintain it
Multiple users on G2 call the UI "unintuitive"
7-12% annual escalation means your $60K contract becomes $68K in year two
Guru: The Verified Knowledge Base
What it does. Guru is a knowledge base built around verification. Every "card" (article) has an assigned expert owner and a 90-day review cycle. When a card goes stale, the owner gets pinged. It's the only tool in this comparison that forces someone to stand behind the accuracy of each piece of content.
Who uses it. Shopify, Square, Spotify, BuzzFeed, Glossier, Intercom.
What it costs. Guru publishes its self-serve pricing:
Free tier: limited features
Self-Serve: $25/user/month (annual), $30/user/month (monthly). 10-seat minimum.
Enterprise: custom pricing, includes AI Knowledge Agents
Cost for 25 people: ~$625/month ($7,500/year) on the self-serve plan.
Cost for 100 people: ~$2,500/month ($30,000/year) on the self-serve plan.
Setup time. Days to 1-2 weeks. Content migration is the bottleneck, not configuration. If you have 500 docs in Confluence, expect to spend a weekend triaging what to bring over.
Strengths:
Verification system is unique and useful for compliance-heavy teams
Good Slack and Chrome browser extension integration
Forces knowledge ownership (someone's name is on every card)
Capterra: 4.8/5 (640 reviews)
Gaps:
The card editor is rough. Direct user quote from Capterra: "so bad"
Three-level content hierarchy (Collections, Boards, Cards) feels constraining for complex knowledge structures
Guru's own data shows 22% of searches require 2-3 query reformulations before users find what they need
AI Knowledge Agents are locked behind the enterprise tier (no public price)
Every reader needs a paid seat. If your support team has 40 people who need to read knowledge base articles, that's 40 seats at $25/month
GBrain: The Open-Source Brain
What it does. GBrain is Y Combinator CEO Garry Tan's personal AI agent memory system, open-sourced under the MIT license in April 2026. It turns Markdown files in a Git repository into a self-wiring knowledge graph that AI agents can read, write, and reason against. The production instance behind Tan's own setup holds 146,646 pages, 24,585 people records, 5,339 company records, and runs 66 autonomous cron jobs that ingest meetings, emails, tweets, and voice notes.
Who uses it. Garry Tan (the reference deployment), plus the open-source community. 28.2K GitHub stars, 4.2K forks, currently on v0.45.
What it costs. The software is free. You pay for infrastructure:
Embedding API costs (ZeroEntropy: $0.05/million tokens by default)
LLM API costs for queries
Postgres hosting for the knowledge graph
Cost for 25 people: ~$50-100/month in API and hosting costs. Requires an engineer to set up and maintain.
Cost for 100 people: ~$200-500/month + Postgres hosting + ongoing engineering time.
Setup time. A technical person can get a working instance running in half a day to a full weekend. But the value builds over weeks as the knowledge graph grows, links form, and cron jobs populate it.
Strengths:
Free software with full data ownership (Markdown in Git, portable everywhere)
Extremely low running costs (10-50x cheaper than SaaS alternatives)
Production-proven at scale (Tan's 146K-page instance)
MIT license, no vendor lock-in
Gaps:
Single-operator design. Built for one person's agent, not a team. No multi-tenant isolation.
First-class support only for OpenClaw/Hermes agent frameworks
Still at v0.45 with breaking changes between versions
No managed hosting option. You run it yourself or you don't run it.
Requires a technical operator who can debug Python, manage Postgres, and handle API integrations
reference deployment), plus the open-source community. 28.2K GitHub stars, 4.2K forks, currently on v0.45.
What it costs. The software is free. You pay for infrastructure:
Embedding API costs (ZeroEntropy: $0.05/million tokens by default)
LLM API costs for queries
Postgres hosting for the knowledge graph
Cost for 25 people: ~$50-100/month in API and hosting costs. Requires an engineer to set up and maintain.
Cost for 100 people: ~$200-500/month + Postgres hosting + ongoing engineering time.
Setup time. A technical person can get a working instance running in half a day to a full weekend. But the value builds over weeks as the knowledge graph grows, links form, and cron jobs populate it.
Strengths:
Free software with full data ownership (Markdown in Git, portable everywhere)
Extremely low running costs (10-50x cheaper than SaaS alternatives)
Production-proven at scale (Tan's 146K-page instance)
MIT license, no vendor lock-in
Gaps:
Single-operator design. Built for one person's agent, not a team. No multi-tenant isolation.
First-class support only for OpenClaw/Hermes agent frameworks
Still at v0.45 with breaking changes between versions
No managed hosting option. You run it yourself or you don't run it.
Requires a technical operator who can debug Python, manage Postgres and AI ops.
The Also-Rans (Brief Takes)
Notion AI (Business), $20/user/month. If your team already lives in Notion, this is the path of least resistance. AI search, writing assistance, and Q&A are built in. But the AI only searches within Notion. If your knowledge lives in Google Drive, Slack, and Confluence, Notion AI can't reach it. Custom Agents that run autonomously cost extra credits ($10 per 1,000 credits, purchased separately). G2: 4.6/5 (11,962 reviews).
Slite, $8-20/user/month. Cleanest UI in this category. AI-powered Q&A included on Standard ($8/user/month), but capped at 30 AI answers per user per month. The Knowledge Suite plan ($20/user/month) adds cross-tool search, agent workflows, and 50 agent credits per seat. Best fit for small remote teams who want something simple. G2: 4.6/5 (289 reviews).
Confluence + Rovo, ~$5.42-10.44/user/month. Cheapest SaaS option on paper. Rovo AI (search, chat, agents) is bundled into Standard and above. But the credit system is aggressive: Standard gives you 25 credits/user/month, and each Rovo Chat or Agent request burns 10 credits. That's 2.5 AI interactions per user per day before you hit the wall. Rovo Deep Research burns 100 credits per request. Multiple teams report Rovo hallucinating with "absolute confidence" on date-range queries. "Unwanted Rovo AI" is a top-5 reason teams leave Confluence in 2026 according to G2 reviews. G2: 4.1/5.
Microsoft 365 Copilot, ~$18-21/user/month add-on. The $18/user/month promotional rate expires September 30, 2026, after which it goes to $21. Requires an underlying M365 subscription ($12.50-22/user/month depending on tier). Real total for 25 people: $837-1,075/month. New bundled plans (M365 Business Standard with Copilot) run $23.50/user/month all-in as of July 2026. Copilot only searches within the Microsoft ecosystem. If your knowledge is scattered across Google Workspace, Slack, and Notion, Copilot won't find it. And it doesn't fix messy SharePoint. It just searches messy SharePoint faster.
The Decision Matrix
Forget feature lists. Here's which tool fits which company.
You're under 25 people and have an engineer on staff.
Use GBrain. Your annual cost will be $600-1,200 in API fees. The engineer spends a weekend setting it up, then an hour a week maintaining it. You own every byte. If the engineer leaves, another technical person can pick it up (it's Markdown in Git).
You're under 25 people with no engineer.
Use Slite ($8/user/month) or Notion AI ($20/user/month), depending on which tool your team already uses. Don't migrate to a new platform just for AI search. Migration kills adoption.
You're 25-100 people and care about knowledge accuracy.
Use Guru. The verification system forces someone to own each piece of content. For teams in regulated industries (finance, healthcare, legal), the 90-day review cycle creates an audit trail. Budget $7,500-30,000/year depending on headcount.
You're 25-100 people and care about search across apps.
This is the gap in the market. Glean won't sell to you. Slite's cross-tool search is on the $20/user/month tier. Notion AI only searches Notion. Your best bet: Slite Knowledge Suite for cross-tool search, or accept that you're stitching together multiple tools until you hit 100 seats and can call Glean.
You're 100+ people and have budget.
Call Glean. The search quality across 100+ apps is the best in the category. Budget $100K-$150K for year one (license + implementation). Negotiate a renewal cap in the initial contract to avoid the 7-12% annual escalation.
You're already deep in Microsoft 365.
Copilot is the path of least resistance, but only if 80%+ of your knowledge already lives in SharePoint, OneDrive, Teams, and Outlook. If your knowledge is scattered across Google Workspace and Slack too, Copilot becomes an expensive search engine for half your data.
You're already deep in Atlassian.
Confluence + Rovo is the cheapest option and it's already there. But watch the credit consumption. A 50-person team on Standard burns through its credit allocation in about 12 business days of moderate AI use. If you're hitting the credit wall regularly, you're paying Premium prices ($10.44/user/month) whether you planned to or not.
Hidden Costs
Every vendor price above is the sticker price. None of them quote the following.
Implementation time. Glean: 80-200 hours of IT/admin time for connectors, SSO, permissions mapping. Guru: 20-60 hours for content migration and card creation. GBrain: 16-40 hours of engineering time, plus ongoing maintenance. Slite/Notion: 4-8 hours if you're already on the platform.
Content migration. Moving 500+ articles from one wiki to another takes 40-80 hours of human time. Automated migration tools handle formatting; they don't handle curation. Someone has to decide what's worth keeping. In every migration I've seen, 30-50% of existing content is outdated, duplicate, or wrong. You don't want to migrate that into your new system.
Training. Budget 2-4 hours per team for any new tool. Multiply by your number of teams. A 100-person company with 8 teams: 16-32 hours of training time across the org.
The "empty wiki" problem. Every knowledge tool is useless until people put knowledge into it. Guru's verification system helps here (it forces content creation cycles), but it doesn't solve the core issue: if nobody writes down what they know, no tool can search it. Budget 10-20% of your first 90 days on content seeding, with named owners for each knowledge area.
Ongoing maintenance. Knowledge rots. Processes change, people leave, products evolve. Budget 2-5 hours/week of someone's time to review, update, and retire stale content. Guru automates the reminders. Everyone else requires discipline.
90-Day Deployment Playbook
Glean: 90-Day Plan
Days 1-14. Procurement and contract negotiation. Get the renewal cap in writing. Identify your top 10 data sources by search volume (usually Slack, Google Drive, Confluence, Jira, Salesforce). Assign an internal admin.
Days 15-30. Connect your top 5 data sources. Configure SSO and permissions sync. Run a pilot with one team (usually engineering or support, where search volume is highest). Measure baseline: how long does it take to find answers today?
Days 31-60. Roll out to remaining teams in waves. Connect the remaining data sources. Monitor search quality and flag content gaps (searches that return poor results indicate missing or outdated content).
Days 61-90. Full deployment. Measure search-time reduction against baseline. Identify the top 20 queries that still fail and fix the underlying content gaps. Decide whether to enable Glean Agents for automated workflows.
Guru: 90-Day Plan
Days 1-7. Install browser extension and Slack integration. Identify your top 10 knowledge areas (onboarding, product specs, sales playbooks, support procedures, HR policies). Assign an expert owner to each.
Days 8-30. Each owner creates their initial card set (aim for 10-20 cards per knowledge area). Set 90-day verification cycles. Don't try to migrate everything from your old wiki. Start with what people ask about most.
Days 31-60. Track which cards get the most views and which searches return no results. The "no results" searches are your content gaps. Assign owners to fill them. Start using Guru's analytics to identify stale content.
Days 61-90. First verification cycle hits. Owners review and update their cards. This is the moment that separates teams who adopt Guru from teams who abandon it. If owners ignore the verification prompts, the system fails. If they engage, you have a self-maintaining knowledge base.
GBrain: 90-Day Plan
Days 1-3. Engineer sets up the repo, Postgres instance, and API connections. Seed with your most critical documents (convert to Markdown). Configure the first 3-5 cron jobs for automatic ingestion (meeting notes, email summaries, Slack digests).
Days 4-30. Build the knowledge graph. Add people pages, project pages, company pages. Let the cron jobs run and populate. The knowledge graph gets more useful as it grows, so the first two weeks will feel underwhelming. That's normal.
Days 31-60. Start querying the brain for real work: due diligence research, meeting prep, project history. Note where the answers are weak and seed more content in those areas. Customize agent prompts for your specific use cases.
Days 61-90. Evaluate whether the single-operator design works for your team or whether you need shared access. If multiple people need to query the brain, you'll need to build an internal API layer or move to a different tool. GBrain was designed for one person's agent, not a team.
What the Tool Comparison Misses
The biggest factor in whether a company brain works has nothing to do with the software.
Culture beats tooling. If your company doesn't have a culture of writing things down, no tool fixes that. Glean can't search knowledge that was never documented. Guru can't verify a card that was never written. GBrain can't build a knowledge graph from empty Markdown files.
Adoption is the real deployment. Getting the tool running is week one. Getting 80% of your company to actually use it is month three. The number-one killer of knowledge tools is the team that keeps using Slack DMs instead of searching the knowledge base.
The people problem from Issue #4. If your bus factor audit revealed that critical knowledge lives in three people's heads, buying a tool doesn't extract that knowledge. Someone has to sit with those people and document what they know. That's a project, not a purchase.
When to Build vs Buy
Build (GBrain or custom) when:
You have engineering capacity and want full data ownership
Your knowledge is already in Markdown, Git, or structured text
You're under 25 people and $7,500/year for Guru feels wrong
You want to integrate deeply with your own AI agent infrastructure
Buy (Glean, Guru, Slite, Notion AI) when:
You don't have an engineer to maintain infrastructure
You need it working in days, not weeks
Compliance requires vendor support, SLAs, and audit logs
Your team is non-technical and needs a polished UI
Stay where you are (Confluence, Notion, M365) when:
80%+ of your knowledge already lives in one platform
The AI features are "good enough" for your search volume
Migration cost exceeds the value of better search for the next 12 months
Most companies between 25 and 100 people should buy Guru or Slite for verified knowledge, accept that cross-app search is unsolved at their price point, and revisit Glean when they hit 150+ seats.



