The Best PKM Stack for Knowledge Workers in 2026

The personal knowledge management space has exploded. Notion, Obsidian, Roam, Logseq, Capacities, Tana, Mem, Reflect — dozens of tools promising to be your “second brain.”

Here’s the uncomfortable truth: no single tool does everything well.

The knowledge workers who actually build functional PKM systems don’t rely on one app. They build a stack — specialized tools connected by clear data flows.

This guide breaks down the optimal PKM stack for 2026, layer by layer. You’ll see how each piece fits together, which tools to choose for your workflow, and how to connect them into a system that compounds over time.

The Four Layers of a PKM Stack

Every knowledge management system needs four distinct capabilities:

Most PKM failures happen because people try to force one tool to handle all four layers. Notion becomes bloated. Obsidian fills with unprocessed bookmarks. The read-later queue becomes a guilt pile.

The solution: dedicated tools for each layer, connected by intentional workflows.

Layer 1: Capture — Arivu

The problem: You encounter valuable content constantly — articles, research, Twitter threads, YouTube videos, documentation. Traditional bookmarks become graveyards. Read-later apps become guilt queues.

The solution: An AI-powered capture layer that processes content immediately.

Why Arivu for Capture

Arivu handles web content capture differently than traditional bookmark managers:

Instant processing. When you save a link, AI reads it immediately and generates:

• One-sentence summary
• Key bullet points
• Important quotes
• Automatic topic tags

You capture the value at the moment you save, not weeks later when you finally read it.

Semantic search. Find content by meaning, not keywords. Search “that article about focus and deep work” and find relevant bookmarks even if those exact words don’t appear.

Intelligent resurfacing. Spaced repetition brings valuable content back at optimal intervals. Your captures don’t disappear — they return when relevant.

Knowledge graph. Visual connections between topics show how your saved content relates.

What Belongs in the Capture Layer

• Articles and blog posts
• Twitter/X threads worth saving
• YouTube videos (with transcript summaries)
• Documentation pages
• Research papers (abstracts and links)
• Product pages for reference
• Anything you might want to find again

What Doesn’t Belong

• Books (use Reading layer)
• Your own notes and ideas (use Notes layer)
• Action items (use Tasks layer)

Key insight: The capture layer is for external knowledge — content created by others. Your own thinking belongs in the notes layer.

Layer 2: Notes — Choose Your Style

The notes layer is where you do your own thinking. This is where you synthesize captured content into original ideas, create atomic notes, and build connections.

Three dominant approaches have emerged. Choose based on how your brain works.

Option A: Obsidian — For Linked Thinkers

Best for: People who think in connections, researchers, writers, developers.

Obsidian stores notes as local Markdown files. You own your data completely. The plugin ecosystem is massive.

Core workflow:

1. Create atomic notes (one idea per note)
2. Link aggressively with [[wikilinks]]
3. Let the graph view reveal unexpected connections
4. Use daily notes as an inbox

Standout features:

• Local-first, Markdown files you own forever
• 1000+ community plugins
• Canvas for visual thinking
• Publish for sharing publicly

Integration with Arivu: Export summaries and highlights from your capture layer → import as Markdown notes → link to your existing knowledge.

Option B: Notion — For Structured Thinkers

Best for: Teams, project managers, people who think in databases, structured thinkers.

Notion combines documents and databases. Everything is blocks that can be rearranged, linked, and templated.

Core workflow:

1. Create databases for different content types (notes, projects, resources)
2. Use linked databases to create views
3. Templates standardize your capture
4. Relational databases connect everything

Standout features:

• Databases with multiple views
• Team collaboration built-in
• API for custom integrations
• Templates for consistency

Integration with Arivu: Web clipper captures → process in Arivu → export to Notion database for long-term storage and connection to projects.

Option C: Roam/Logseq — For Outliner Thinkers

Best for: Researchers, academics, people who think hierarchically, daily journalers.

Roam and Logseq use an outliner structure where everything is a bullet point. Blocks can be referenced and embedded anywhere.

Core workflow:

1. Daily notes are the default entry point
2. Everything is a bullet that can be indented
3. Block references embed content across notes
4. Queries pull related content together

Standout features:

• Block-level linking and embedding
• Powerful queries
• Daily notes workflow
• Bidirectional links visible in context

Integration with Arivu: Capture summaries → paste into daily notes → link to relevant topics → block references surface connections.

Which Should You Choose?

Don’t overthink it. The best tool is the one you’ll actually use. All three can build a functional second brain.

Layer 3: Reading — Readwise Reader

The problem: Long-form content — books, PDFs, newsletters — needs deeper engagement than articles. You need to highlight, annotate, and extract insights over days or weeks.

The solution: A dedicated reading layer with highlight export.

Why Readwise Reader for Reading

Readwise Reader consolidates all long-form reading in one place:

Everything in one queue. Books, PDFs, articles, newsletters, YouTube transcripts — all in the same interface.

Highlight and annotate. Mark important passages. Add your thoughts. Tag for retrieval.

Automatic export. Highlights sync to Obsidian, Notion, Roam automatically. Your reading becomes notes without manual copying.

Spaced repetition. Readwise’s original feature — highlights resurface via email and app for long-term retention.

What Belongs in the Reading Layer

• Books (ebooks and physical via OCR)
• PDFs and research papers (for deep reading)
• Long-form articles (1500+ words)
• Newsletters you want to engage with deeply
• YouTube videos you want to annotate

Reading Layer vs Capture Layer

Capture (Arivu): Quick saves, AI-processed, searchable reference. You might never read the full content.

Reading (Readwise Reader): Intentional reading queue, highlights and annotations, deep engagement expected.

The distinction matters. Not everything you save needs deep reading. Most captured content is reference material — the AI summary is enough. Reserve your reading layer for content worth your focused attention.

Layer 4: Tasks — Todoist or Things

The problem: Knowledge without action is trivia. You need to convert insights into tasks, projects, and deadlines.

The solution: A dedicated task manager that stays simple.

Why Separate Tasks from Notes?

It’s tempting to manage tasks in Notion or Obsidian. Don’t.

Notes apps are for thinking. Task apps are for doing. Mixing them creates friction in both directions:

• Tasks buried in notes get forgotten
• Notes cluttered with todos become hard to read
• You lose the focused “what do I need to do right now?” view

Todoist — Cross-Platform Power

Best for: People who need tasks everywhere, natural language input lovers, GTD practitioners.

Standout features:

• Natural language input (“Call client tomorrow at 2pm #work p1”)
• Powerful filters and labels
• Works everywhere (web, desktop, mobile, browser extension)
• Integrations with everything
• Team features available

Things 3 — Apple-Only Elegance

Best for: Apple users who value design, people who want simplicity, GTD practitioners.

Standout features:

• Best-in-class design and UX
• Headings within projects
• Areas for life categories
• Quick entry from anywhere on Mac
• One-time purchase (no subscription)

Tasks Workflow

1. Capture tasks when they arise — during reading, browsing, or meetings
2. Review weekly — what needs to happen next week?
3. Process daily — what are today’s 3-5 priorities?
4. Link to notes when needed — reference your PKM for context

Key insight: Tasks should be actionable. “Learn about machine learning” is not a task. “Read chapter 1 of [book]” and “Watch [specific video]” are tasks.

How Data Flows Through the Stack

Here’s how information moves through a well-designed PKM stack:

DISCOVER → CAPTURE → PROCESS → STORE → ACT
   ↓          ↓          ↓         ↓       ↓
Browser    Arivu    Read/Note    Notes   Tasks
content    saves    in depth     layer   layer
           + AI     if needed

Example: Research Article

1. Discover — Find an interesting research paper via Twitter
2. Capture — Save to Arivu → AI generates summary and key points
3. Decide — Is this worth deep reading?
   • No: The summary is enough. It’s searchable in Arivu forever.
   • Yes: Send to Readwise Reader queue.
4. Process — Read in Reader, highlight key passages, add annotations
5. Store — Highlights auto-export to Obsidian. Create atomic notes. Link to related ideas.
6. Act — Add task: “Write blog post about [topic]” in Todoist

Example: Quick Reference

1. Discover — Find documentation for an API you’ll need later
2. Capture — Save to Arivu → AI extracts key details
3. Done — No further processing needed. When you need it, semantic search will find it.

Most captured content stops at step 2. That’s the point. Your capture layer prevents content from getting lost while preserving your attention for content that deserves deeper engagement.

Stack Recommendations by User Type

Different workflows need different stacks. Here are optimized recommendations:

The Researcher

Profile: Academic, journalist, analyst. Deep research projects spanning months.

Key workflow: Heavy use of knowledge graph to find connections. Atomic notes for each source. Zettlekasten-style linking.

The Creator

Profile: Writer, YouTuber, podcaster. Constant content production.

Key workflow: Ideas captured → processed into content briefs → scheduled in content calendar → produced on deadline.

The Generalist

Profile: Curious knowledge worker. Reads widely, applies broadly.

Key workflow: Liberal capture, periodic review, notes only for significant insights. Resurfacing keeps valuable content visible.

The Minimalist

Profile: Wants function without fuss. Least number of tools possible.

Key workflow: Arivu handles most capture and retrieval. Notes only for original thinking. Keep the stack as simple as possible.

Common PKM Stack Mistakes

1. Tool Churn

Switching tools every few months destroys compound value. Your second brain needs time to grow.

Fix: Commit to a stack for at least 6 months. Evaluate at a scheduled review, not when a shiny new tool appears.

2. Over-Processing

Not every saved link needs a Zettlekasten note. Most captured content should stay in your capture layer.

Fix: Only process to notes when you’re doing original thinking. AI summaries are enough for reference material.

3. No Action Layer

A knowledge system without task management is just sophisticated procrastination.

Fix: Every research session should produce at least one actionable task.

4. Ignoring the Capture Layer

Going straight from browser to Notion or Obsidian creates noise in your notes system.

Fix: Arivu filters and processes before content reaches your notes. Most things you save don’t need permanent notes.

5. Complexity Theater

Building elaborate systems that look impressive but don’t serve your actual work.

Fix: Ask: “Does this system help me produce better output?” If not, simplify.

Setting Up Your Stack: Quick Start

Week 1: Capture Layer

1. Join the Arivu waitlist
2. Install browser extension
3. Save 20+ things — don’t organize, just capture
4. Explore AI summaries and semantic search

Week 2: Notes Layer

1. Choose: Obsidian, Notion, or Roam
2. Create a simple structure (don’t over-engineer)
3. Process 3-5 items from your capture layer into notes
4. Start linking ideas

Week 3: Reading Layer

1. Set up Readwise Reader
2. Move 5 items from capture to reading queue
3. Read and highlight
4. Configure export to your notes app

Week 4: Tasks Layer

1. Choose: Todoist or Things
2. Set up areas/projects for your main life categories
3. Capture tasks that emerge from your knowledge work
4. Establish daily and weekly review habit

FAQ

Do I really need four separate tools?

You need four capabilities. Some tools can handle multiple layers. But specialized tools do each job better. Start with capture + notes. Add reading and tasks as your system matures.

What about Mem, Reflect, or other AI-native notes apps?

They’re promising but blur the line between capture and notes. If you want all-in-one, try them. If you want specialized excellence, use a layered stack.

How do I avoid information overload?

The capture layer is your filter. Most saved content stays there — AI summaries are enough. Only promote to notes what deserves original thinking. The stack reduces overload by creating clear tiers.

What’s the learning curve?

Each tool: 1-2 hours to set up basics. Full proficiency: 2-3 months. The stack as a system: 6+ months to develop mature workflows.

Can I use this stack for a team?

Individual knowledge management is personal. For teams, add a shared layer — typically Notion for collaborative knowledge bases. Individual stacks feed into shared resources.

How much does this stack cost?

• Arivu: Free tier available, premium TBD
• Obsidian: Free (Sync $8/month optional)
• Notion: Free for personal use
• Readwise Reader: $9.99/month
• Todoist: Free tier available, Pro $4/month
• Things: $50 one-time (Mac) + $10 (iOS)

Minimal stack: ~$10/month Full stack: ~$15-20/month

Build Your Capture Layer First

The capture layer is the foundation of any PKM stack. Without reliable capture, the rest of the system starves.

Arivu is purpose-built for this layer. AI summaries process content immediately. Semantic search finds anything you’ve saved. Intelligent resurfacing brings valuable content back before you forget it.

Start here. Build up.

Join the Arivu waitlist →

For a deep dive on building your second brain, read: How to Build a Second Brain with AI Bookmarking