Software development course in Peru

Many self-taught programmers in Peru reach the middle column and stop. They can write code that works on their laptop, but have never had to keep a program running after other people started depending on it. Our projects run long enough for that to happen: learners return to their own code months later, fix issues raised by the mentor, and discover why the documentation they skipped would have helped.

Our Spanish page, curso de desarrollo de software en inglés, covers the industry figures, secure software and competitive programming, with a lesson on classes that protect their own rules. Here we follow the process itself.

Process names and grouping: NTP-ISO/IEC 12207:2004, sections 5 to 7, as annexed to RM 179-2004-PCM. The 2016 edition reorganises the processes; we teach from the 2004 text because its public copy is readable and its structure is simple.

The supporting processes are where beginners are weakest and employers care most. Configuration management in particular sounds bureaucratic until the first time a project breaks because two people changed the same file, or because a part was built before the part it depends on. The lesson below is about the second of those.

needs = {
    "login":     {"database", "passwords"},
    "passwords": {"database"},
    "reports":   {"database", "login"},
    "database":  set(),
    "emails":    {"login"},
}

built = set()
for part in sorted(needs):              # alphabetical order
    missing = needs[part] - built
    if missing:
        print("FAIL", part, "needs", sorted(missing))
    else:
        print("ok  ", part)
    built.add(part)

from graphlib import TopologicalSorter, CycleError

needs = {
    "login":     {"database", "passwords"},
    "passwords": {"database"},
    "reports":   {"database", "login"},
    "database":  set(),
    "emails":    {"login"},
}

print("Build order:", list(TopologicalSorter(needs).static_order()))

needs["database"] = {"reports"}         # a "small change" on Friday
try:
    list(TopologicalSorter(needs).static_order())
except CycleError as err:
    print("Cycle:", " -> ".join(err.args[1]))

An order in which every part comes after everything it needs is called a topological order, and graphlib.TopologicalSorter finds one. Read the cycle line as "is needed by": the login is needed by reports, reports are now needed by the database, and the database is needed by the login. Nothing in that loop can be built first.

That one line on Friday, "the database should produce a report when it starts", was reasonable as a feature and impossible as a structure. The lesson is not about Python. Maven, Gradle, npm and every serious build tool do the same calculation, and the developer who understands it can read their error messages instead of fearing them. In the NTP-ISO/IEC 12207 vocabulary above, this is configuration management doing its job.

1. Predict. Add a part called "search" that needs reports. Where does it appear in the order, and is that the only valid place?
2. Count. Without the Friday change, how many different valid build orders are there? Write a program that counts them.
3. Repair. Remove the cycle without losing the feature: what would you split into two parts?
4. Transfer. In the Java course, find the same idea in a Gradle error and explain it to a classmate.

The system, code and output are ours, written for this page and run with Python 3 on 9 November 2026. The graphlib module is part of the Python standard library.

Our plan, not a guarantee. Learners with a university programming course behind them often start at month 3; those who practise less move more slowly. We promise no job or salary.

If you are at university in Peru, our page on programación para universitarios explains how these courses sit beside a Peruvian degree, and the Java course page in Spanish compares Java versions and frameworks in more depth.

Peru: UTC minus 5 throughout the year, no daylight saving since 1994 (tz database zone America/Lima). India: UTC plus 5:30. Difference: 10 hours 30 minutes on every date.

Book in your own clock and the system converts it for the mentor. Many working adults in Peru change their slot when a project at work gets busy; with one to one classes that is a message, not a negotiation.