In software, there’s one ironclad law: it always takes longer than you think. That quick fix? Turns into a week-long detour. That “straightforward” feature? Suddenly, you’re neck-deep in undocumented edge cases. We joke about it – Hofstadter’s Law, the 90/90 rule – but it’s a reality teams live with daily.

So why does estimation fail so reliably? And more importantly, what can we do about it?

Let’s talk unknown unknowns, and how Cosine, our autonomous AI engineer, helps you conquer them.

The Real Bottleneck: Unknown Unknowns

Every engineering team has war stories: a two-line change that derailed a sprint, or a “trivial” task that revealed a whole architectural mess. The culprit? Unknown unknowns: the things you don’t even know you don’t know.

When building something new, almost every problem falls into this category. That’s why timelines slip. Complexity hides in integration details, implicit requirements, and legacy quirks. Even the best plans can’t predict what they don’t see coming.

The experienced approach? Spend time up front converting unknowns into knowns. That’s what exploration, research, and prototyping are for. But it’s slow, and there are always surprises left over.

Ask a junior dev how long something will take, and you’ll get “two hours.” A senior might say “two days.” Same task. Different mental map.

Why? Experience. The senior engineer doesn’t just see the happy path – they see the risks. They’ve been burned before, and they’ve learned where dragons lurk: outdated dependencies, tangled APIs, performance traps.

The more experience you gain, the more you realise what you don’t know. That’s not pessimism. It’s realism. Estimation isn’t about confidence, it’s about calibrated uncertainty.

How Cosine Tackles Unknowns at Scale

Cosine, our AI software engineer, is built to act like a real teammate, not just autocomplete your code. It works across the full dev lifecycle: planning, coding, testing, fixing, and iterating. And it’s agentic: it takes a goal and runs with it.

This changes the game for estimation. Why? Because Genie helps convert “I’m not sure how long this will take” into “Let’s find out.”

Autonomous Execution

Assign a task like “add dark mode,” and Cosine creates a branch, writes the code, runs the tests, and opens a PR. All autonomously. No babysitting. Just results.

Multi-agents for Research and Planning

AutoPM, Cosine’s built-in product manager, handles the upfront thinking. It reads the codebase, finds relevant patterns, picks tools, and outlines a plan. That research phase,the one you usually skip or rush, is now automatic.

Task Decomposition

When the goal is complex (“Implement SSO”), AutoPM splits it into actionable subtasks. Cosine works through each one, methodically. No more “where do I even start?”

Feedback Loops

Cosine writes code, runs tests, and then responds to review comments – all in the same thread. It’s like pairing with a dev who never forgets feedback and never gets tired.

Slack-Native Workflow

Got a bug report in Slack? Mention @Cosine, and the agent handles it, right there in the thread. No context switching and no delay.

Scale Beyond Human Limits

The real magic? Parallelism. With Cosine, one engineer can kick off 10+ tasks at once. Each runs asynchronously in the cloud. You don’t need to wait for one to finish before starting another. You’re not blocked. You’re scaling.

This breaks the traditional estimation model. Instead of “how many engineers do we need?” it becomes “how many Cosine agents can we deploy?” Backlogs shrink. Projects accelerate.

In this new model, your role evolves. You don’t write every line of code. Instead, you guide, review, and adjust. You become the architect, not the bricklayer.

PMs, too, shift from negotiators to strategists. Instead of slicing scope to fit timelines, you assign it to multiple Cosine agents and monitor progress. Cosine doesn’t get bogged down. It doesn’t burn out. And it makes your roadmap feel achievable again.

Delivering Tomorrow’s Work, Today

Estimates used to be hand-wavy guesses. Now, they can be empirical. Want to know if something’s hard? Let Cosine try it. The result is a reality check within hours, not after burning a sprint.

Of course, software will always have surprises. But with Cosine’s AI engineers, we have leverage. We can uncover unknowns faster, resolve them sooner, and shift from reactive to proactive.

The saying used to be: “Tomorrow is a month away.” With Cosine, tomorrow might just arrive on time.

Ready to try it? Start a task with Cosine and see what’s possible.