A lockup period is the 90 to 180 day window after an IPO during which insiders are contractually barred from selling or transferring their shares. Also called an IPO lockup, the restriction binds founders, employees, pre-IPO investors, and certain other affiliated parties, including from hedging their shares. It is designed to prevent a post-IPO supply shock that would tank the newly-public stock and to give the market time to absorb the float available from the offering itself. It is one of the most important structural features of a traditional IPO and one of the things direct listings deliberately abandon.
The standard structure: the underwriters require all insiders to sign lockup agreements as a condition of the IPO, with...
A seed round is a startup's first substantial round of outside investment. It is raised to turn a working product into early traction and to reach signs of product-market fit, typically following pre-seed capital and preceding a Series A. It's the round where the company transitions from "we're building something" to "we're building something people want," and where the bar for the next round (Series A) gets established.
The 2025 benchmarks (Carta and PitchBook):
| Metric | 2025 typical range | Notes |
|---|---|---|
| Round size | $2.5M-$5M | Hot AI/deep-tech can be $6M-$10M |
| Post-money valuation | $20M-$30M (median ~$24M) | All-time high in 2025; up from ~$18M in 2024 |
| Pre-money valuation | $18M-$25M | Subject to pool refresh placement |
| Founder dilution | ...
Prompt engineering is the practice of crafting effective input prompts to large language models to elicit desired outputs. It encompasses techniques like clear instructions, few-shot examples, structured output specifications, chain-of-thought reasoning, role assignments, context provision, and iterative refinement. The discipline is part craft (intuition for what works) and part science (testable techniques), and is the dominant way to control LLM behavior without fine-tuning. It's the AI-era equivalent of writing good SQL queries: a transferable skill that materially impacts the quality of what you can build.
The core techniques that work:
Clear, specific instructions: vague prompts produce vague outputs.
Bad: "Summariz...
A Large Language Model (LLM) is an AI system trained on massive amounts of text to predict the next token in a sequence. The prediction capability scales into broader abilities (reasoning, code generation, analysis, conversation, translation, summarization) as models grow in size and training data. Modern frontier LLMs range from 70 billion to 1+ trillion parameters and are the technology underlying ChatGPT, Claude, Gemini, Llama, and other generative AI products that have transformed software since 2022. It's the specific type of foundation model that handles text.
What LLMs actually do (the mechanics):
Tokens, not words: LLMs break text into tokens (sub-word units). "Tokenization" of a sentence might produce 10-...
A quarterly business review (QBR) is the recurring strategic review at quarter-end covering OKR achievement, strategic initiative progress, trends, lessons learned, and next-quarter planning. Typically a full-day or multi-day session, it's the strategic equivalent of monthly business reviews (tactical financial) and weekly business reviews (tactical execution), and is distinct from "customer QBRs" (customer success meetings with key accounts) despite the shared acronym. It is the leadership rhythm that closes each quarter and opens the next.
The standard internal QBR structure (1-2 days):
Quarter review (half-day):
Sales-Led Growth (SLG) is the go-to-market motion in which a dedicated sales team drives customer acquisition through outbound prospecting, demos, consultative selling, and contract negotiation. Marketing supports the motion by generating awareness and pipeline rather than directly converting leads. It's the traditional B2B SaaS motion, dominant for higher-ACV products and complex sales cycles, and the counterpart to [Product-Led Growth] (where the product drives acquisition without sales intervention).
When SLG is the right motion:
Higher ACV ($30K+): the deal size justifies the cost of sales reps.
Complex products: requiring consultative selling, demos, technical evaluation, and customization.
Multi-stakeholder buyi...
Customer interviews are structured one-on-one conversations with current or prospective customers, designed to understand needs, behaviors, pain points, decision processes, and value drivers. They're used at every stage of company building, from problem validation pre-product, to product validation during MVP, pricing research, account expansion, and customer health monitoring, conducted via video, phone, or in-person. Customer interviews are one of the most-leveraged sources of insight and the technique that separates founders building from evidence from founders building from assumption. It is the foundational customer-learning method.
The interview structure:
Preparation (often more important than the interview itself...
Addressable market is the portion of a total market a company can realistically serve given product capabilities, geographic reach, target segments, channels, and regulatory constraints. Often synonymous with SAM (Serviceable Addressable Market) in the TAM/SAM/SOM framework, it's typically much smaller than total market (TAM) but more strategically meaningful because it represents customers the company can actually pursue today. It is the market-sizing concept that most directly informs go-to-market strategy and resource allocation, more useful than total TAM for actual operating decisions.
What constraints define addressable market:
Product constraints:
User experience (UX) is the total quality of a user's interaction with a product across usability, accessibility, performance, content, design, and emotional response. It treats the product as the experience the user actually has rather than just the interface they see, covering information architecture, visual design, and microinteractions. The term was coined by Don Norman at Apple in 1993 to capture everything that shapes how a person perceives and interacts with a system, beyond just visual design.
The components of modern UX work cluster into roughly six areas: usability (can the user accomplish what they're trying to do, with what speed and what error rate), information architecture (how content and functionality are o...
Usability testing is the practice of observing real users complete tasks in a product or prototype to identify friction and failures before shipping at scale. It can be run moderated (a researcher guides the session live) or unmoderated (the user records themselves through a remote-testing platform), in person or remote, on the live product, a prototype, or a competitor's product. It is the highest-signal-per-dollar method in the user-research toolkit and the one most consistently skipped by founders who assume their product is obvious.
The canonical reference, from Jakob Nielsen's research at the Nielsen Norman Group (1990s onward): 5 users surface roughly 85 percent of usability issues on a given interface, after which r...