Blog
Mert Özen's blog posts on software development, backend, frontend, and DevOps.
From Discovery to Delivery: One-Pagers, PRDs and Turning Decisions into Backlog Items
A good one-pager or PRD answers two questions: why are we doing this, and how will we know we succeeded? We write the one-page document for Bookstore's cart abandonment work with problem, target outcome, success metric, non-goal, risk and open question sections, turn the decision into backlog items split into end-to-end slices, and cover the questions a developer should ask in a PRD review.
Deciding with Experiments: A/B Tests, Feature Flags and Statistical Pitfalls
An A/B test is trustworthy when its sample is computed before the experiment and you wait for it. We test Bookstore's shipping cost hypothesis with a Microsoft.FeatureManagement variant flag and see in C# output that it needs 3,954 carts per arm, how the SRM check works, the confidence interval of a 2.24-point lift, and how peeking daily raises false positives in no-effect A/A tests from 5% to 32%.
Measuring Product Metrics in Code: Event Tracking and Cohort Analysis with Angular and ASP.NET Core
Product metrics start with an event taxonomy that lives in code: object_action names, an allowed property list and a schema version. We write a consent-aware AnalyticsService in Angular and an event table with an ASP.NET Core Minimal API and EF Core, compute a weekly retention cohort and an ordered activation funnel in SQL Server with real query output, and cover KVKK/GDPR concerns and a ready-made tool versus your own table.
Product Metrics: North Star, HEART and AARRR
A good product metric drives decisions: the North Star summarizes delivered value in one number, input metrics are levers teams can move weekly, guardrails catch the side effects of optimization. We build a metric tree for Bookstore, measure guest checkout with HEART and Goals-Signals-Metrics and the customer lifecycle with AARRR, and discuss leading versus lagging and vanity metrics.
Building a Roadmap: Now-Next-Later and Outcome Roadmaps Instead of Feature Timelines
A roadmap that lists features month by month is made of promises given at the moment of least information, and it slips every year. Through Bookstore's roadmap for the first half of 2027 we cover the vision, strategy, roadmap and backlog hierarchy, Now-Next-Later's columns of uncertainty, outcome roadmaps whose rows are problems and measures, communicating with confidence ranges, and Shape Up's appetite and betting table.
Prioritization Frameworks: RICE, MoSCoW, Kano and Cost of Delay
No single prioritization framework ranks all work correctly: RICE sees impact per effort but not time, CD3 sees urgency but rests on a CoD estimate. We rank Bookstore's six items both ways in TypeScript, see the payment SDK upgrade come last in RICE and first in CD3 and one confidence value reshuffle the order, and cover MoSCoW, Kano, WSJF and scoring technical debt.
Product Discovery: Continuous Discovery, User Interviews and the Opportunity Solution Tree
Product discovery is not a phase but a continuous practice with customer touchpoints at least weekly. Through Bookstore's cart abandonment tree we show why good interviews ask about past behavior and walk through the Opportunity Solution Tree's outcome, opportunity, solution and assumption test levels; then fake door, concierge and prototype tests, and the developer's role in dual-track.
Outcomes over Output: Problem Statements, Hypotheses and Jobs to Be Done
Give a team an outcome goal (a change in behavior), not an output (a feature): output is controllable but guarantees nothing, and impact is too far from the team. We frame Bookstore's 66.7% cart abandonment problem without jumping to a solution, covering a four-part problem statement, a falsifiable hypothesis format, guardrails, Jobs to Be Done and how job stories differ from user stories.
What Is Product Management? Product Manager vs Product Owner vs Project Manager
Product management is about building the right thing: a project delivers scope by a date, a product keeps producing value. Through Bookstore's campaign request we cover why the Product Manager is a job role, the Product Owner a Scrum accountability and the Project Manager a time-scope-budget role; Cagan's four risks, the feature factory versus the empowered team, and the developer's place in feasibility.
Scrumban and the Kanban Guide for Scrum Teams: Adding Flow to Scrum
Adding flow to Scrum doesn't require dropping the Sprint: the Kanban Guide for Scrum Teams adds a DoW, WIP limits and the four flow metrics to Sprint Planning, the Daily Scrum, Review and Retrospective without changing any part of the Scrum Guide. We cover Scrumban as Ladas described it, as a transition path, its loose use today, and choosing Scrum, Kanban or both for support, platform and product teams.
Actively Managing Flow in Kanban: Blockers, Aging and Flow Reviews
Actively managing flow means reading the board right to left from the oldest item every day, escalating blocked work, limiting expedite and finding the bottleneck with data. We compute CFD band widths from Bookstore data in C#, see how Code Review became the bottleneck in July, how the Theory of Constraints steps solved it (p85 from 16 to 11 days), and why the next constraint is the deploy rhythm.
Service Level Expectation and Monte Carlo: Answering "When Will It Be Done?" with Probability
For a single item the answer is the SLE ("85% within 14 days"); for many items it is a Monte Carlo simulation that samples historical daily throughput. Running 10,000 times on Bookstore data, our C# code says 30 items finish by 25 November with 50% probability and by 6 December with 85%. We cover reading percentiles from the right end, explaining forecasts to stakeholders and when the forecast goes wrong.