B2D vs B2B: The physics of developer adoption

If you attempt to sell a developer tool using the same playbook as a traditional B2B SaaS platform (say, HR software or a CRM) you will fail. You will burn through your Series A with a customer acquisition cost that makes your unit economics untenable.

The mistake most founders make is assuming "B2B" covers all business software. It does not. Selling soft-skills software to a VP of Sales is a sociological challenge. Selling infrastructure to a Staff Engineer is a physics challenge.

The traditional B2B funnel relies on compliance and promise. You sell a vision to an executive, they sign a contract, and they mandate usage. The users have no choice.

In contrast, the Developer (B2D) funnel relies on utility and verification. The user adopts the tool in spite of their company’s procurement process, proves it works, and then forces the company to buy it.

This essay explores the mechanics of this "Bottom-Up Loop," why standard marketing metrics lie to you, and how to build a distribution engine that respects the psychology of the engineering buyer.

The taxonomy of the buyer

In traditional sales, "Decision Maker" is the target. In 2026, for technical products, the Decision Maker is almost never the Budget Holder.

We must separate the roles into three distinct species with incompatible incentives.

1. The practitioner (user)

• Incentive: Laziness and fear. They want to go home at 5 PM. They are terrified of being paged at 3 AM.
• Buying Criteria: "Does this solve the specific error message I am staring at right now?"
• Power: They cannot sign a check, but they have "Veto Power." If they say a tool sucks, the deal is dead.
• Discovery: Google, Stack Overflow, GitHub, Hacker News. They never talk to analysts.

2. The manager (team lead/EM)

• Incentive: Velocity and stability. They want their team to stop complaining about broken builds. They want to ship features faster.
• Buying Criteria: "Will this integrate with our existing mess (Jira/CI/Legacy Code)?"
• Power: They can approve small budgets (the corporate credit card, ~$500/mo).
• Discovery: Peer recommendations, newsletters, "Best Practice" guides.

3. The executive (CTO/VP)

• Incentive: Risk mitigation and compliance. They don't care about your cool CLI. They care about SOC2, SSO, and not getting sued.
• Buying Criteria: "Is this vendor solvent? Will they exist in 3 years? Do they have Enterprise Support?"
• Power: They sign the $100k contract.
• Discovery: Deeply lagging indicators. They often only hear about a tool after 20 of their engineers are already using it.

The core flaw: Most B2B marketing targets the Executive with "ROI" messaging, yet the Executive doesn't buy until the Practitioner has already installed the software. You are selling to the destination, not the driver.

The adoption loop: A physics model

The B2D funnel is not a funnel. It is a viral loop of verification. It resembles the spread of a virus more than a sales pipeline.

Phase 1: The infection (shadow IT)

A single developer encounters a problem. "My Postgres queries are slow." They search for a solution. They find your tool.

They do not ask for permission.

Recent data from 2024 shows that 30% to 50% of IT spending now happens outside official IT budgets. This is Shadow IT.

If your tool requires a "Contact Sales" form, the infection stops. If your tool allows npm install or a docker pull, the infection takes hold. They run it on localhost. It works. They get a dopamine hit.

This is the "Time to Hello World" metric. It must be as close to zero as possible.

Phase 2: The incubation (local verify)

The developer commits your config file to a feature branch. "Hey, I added this library to fix the N+1 query problem." They push to PR. Now, 3 other engineers review the code. * "What is this dependency?" * "Is it maintained?" * "Did it break the build?"

This is your first major hurdle. Your documentation, your GitHub stars, and your "Last Commit Date" are the marketing assets that help the Practitioner defend your tool to their peers.

Phase 3: The outbreak (team standardization)

The PR merges. The tool is now in the main branch. It goes to production. Three weeks later, another team asks, "How did you fix that query slowness?" The first team shares their implementation. Now 10 developers are using it. You still haven't made a dollar. You might not even know they exist. This is the "Dark Funnel."

Phase 4: The ransom (enterprise conversion)

Eventually, the usage hits a ceiling. They need SSO features. They need Audit Logs. They hit a usage limit. The Manager walks to the VP and says: "Half the team depends on this tool. We need to upgrade to the Enterprise Plan."

The VP has no choice. The software is already entrenched in the infrastructure. Ripping it out would cost more than paying you. The sales cycle was effectively zero days. The "Evaluation" happened during the Shadow IT phase.

Why marketing breaks this loop

If you understand the physics of this loop, you will see why most "Best Practice" marketing tactics act as friction brakes.

1. The gate

Tactic: "Download our Whitepaper on Database Performance." Reality: The Practitioner is not browsing for literature. They are debugging. They want the solution, not a PDF. If you gate the solution, they hit "Back" and go to the open-source alternative. Fix: Give the solution away. Gate the convenience (hosting, UI, collaboration).

2. The "book a demo"

Tactic: "See how we can help your team." Reality: Developers occupy the "Maker Schedule." A 30-minute Zoom call breaks their flow state. It is a high-cost interaction. They perceive a demo as a hostile negotiation where they will be pressured. Fix: The "Self-Serve Demo." A video walkthrough of the interface, not a slide deck.

3. The feature benefit matrix

Tactic: "Increase developer productivity by 30%." Reality: Developers have "Marketing Blindness." They ignore adjectives. "Fast," "Robust," "Scalable" are null values to them. Fix: Technical Specificity. "Written in Rust, compiles to WASM, starts in 50ms." "P99 latency < 10ms." Specific claims are verifiable. Verifiable claims build trust.

Adoption as a function of trust

In B2D, trust is the currency.

A developer is betting their reputation on your tool. If your library causes a memory leak and crashes production, they get blamed, not you. They are risking social capital.

Therefore, your marketing must be an exercise in risk reduction.

• Social Proof: Not "Logos of Fortune 500s" (which could be legacy contracts), but "Who else uses this?" Show GitHub stars, NPM download stats, and testimonials from specific named engineers at respected technical companies.
• Transparency: Discuss your trade-offs. "We optimized for read-heavy workloads, so if you are write-heavy, use something else." Honesty signals competence. A tool that claims to be perfect for everyone is suspicious.
• Community Health: A dead Discord server is a red flag. A GitHub repo with 500 open issues and no responses is a red flag. Your marketing budget should be spent on DevRel engineers who answer issues, not ads.

The metric trap: MQLs vs PQLs

If you hire a standard VP of Marketing, they will optimize for MQLs (Marketing Qualified Leads). * "We got 5,000 emails from the webinar!" * (All 5,000 are @gmail.com addresses of students who wanted the free t-shirt).

The only metric that matters in B2D is the PQL (Product Qualified Lead). * "This account has spun up 5 instances." * "This user invited 3 other users with the same @company.com domain." * "They hit 80% of their free tier limit."

These are signals of the Infection Phase taking hold. This is when your sales team should reach out, not to "sell," but to "assist." "I see you're hitting the limit on API calls. I can bump that up for you while you test, or we can look at a team plan." It’s customer support disguised as sales.

Conclusion: The era of the "silent funnel"

The future of B2B software is B2D. As every company becomes a software company, the buying power shifts from the suit-wearing executive to the hoodie-wearing maintainer.

The companies that win (Stripe, Vercel, Supabase, Datadog) understand that you do not "market" to developers. You equip them. You give them the superpowers they need to solve their problems, and you stay out of their way until they are ready to pay you.

Stop building a funnel. Start building a gravity well.